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2660 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Martin KaFai Lau
|
c9f1155645 |
libbpf: Ensure undefined bpf_attr field stays 0
The commit |
||
Dima Tisnek
|
d47b9f68d2 |
libbpf: Correct bpf_core_read.h comment wrt bpf_core_relo struct
Past commit ([0]) removed the last vestiges of struct bpf_field_reloc,
it's called struct bpf_core_relo now.
[0]
|
||
Kui-Feng Lee
|
9e926acda0 |
libbpf: Find correct module BTFs for struct_ops maps and progs.
Locate the module BTFs for struct_ops maps and progs and pass them to the kernel. This ensures that the kernel correctly resolves type IDs from the appropriate module BTFs. For the map of a struct_ops object, the FD of the module BTF is set to bpf_map to keep a reference to the module BTF. The FD is passed to the kernel as value_type_btf_obj_fd when the struct_ops object is loaded. For a bpf_struct_ops prog, attach_btf_obj_fd of bpf_prog is the FD of a module BTF in the kernel. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240119225005.668602-13-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
||
Andrii Nakryiko
|
bc308d011a |
libbpf: call dup2() syscall directly
We've ran into issues with using dup2() API in production setting, where libbpf is linked into large production environment and ends up calling unintended custom implementations of dup2(). These custom implementations don't provide atomic FD replacement guarantees of dup2() syscall, leading to subtle and hard to debug issues. To prevent this in the future and guarantee that no libc implementation will do their own custom non-atomic dup2() implementation, call dup2() syscall directly with syscall(SYS_dup2). Note that some architectures don't seem to provide dup2 and have dup3 instead. Try to detect and pick best syscall. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Song Liu <song@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20240119210201.1295511-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
Andrey Grafin
|
f04deb90e5 |
libbpf: Apply map_set_def_max_entries() for inner_maps on creation
This patch allows to auto create BPF_MAP_TYPE_ARRAY_OF_MAPS and
BPF_MAP_TYPE_HASH_OF_MAPS with values of BPF_MAP_TYPE_PERF_EVENT_ARRAY
by bpf_object__load().
Previous behaviour created a zero filled btf_map_def for inner maps and
tried to use it for a map creation but the linux kernel forbids to create
a BPF_MAP_TYPE_PERF_EVENT_ARRAY map with max_entries=0.
Fixes:
|
||
Linus Torvalds
|
9d64bf433c |
perf tools improvements and fixes for v6.8:
- Add Namhyung Kim as tools/perf/ co-maintainer, we're taking turns processing
patches, switching roles from perf-tools to perf-tools-next at each Linux
release.
Data profiling:
- Associate samples that identify loads and stores with data structures. This
uses events available on Intel, AMD and others and DWARF info:
# To get memory access samples in kernel for 1 second (on Intel)
$ perf mem record -a -K --ldlat=4 -- sleep 1
# Similar for the AMD (but it requires 6.3+ kernel for BPF filters)
$ perf mem record -a --filter 'mem_op == load || mem_op == store, ip > 0x8000000000000000' -- sleep 1
Then, amongst several modes of post processing, one can do things like:
$ perf report -s type,typeoff --hierarchy --group --stdio
...
#
# Samples: 10K of events 'cpu/mem-loads,ldlat=4/P, cpu/mem-stores/P, dummy:u'
# Event count (approx.): 602758064
#
# Overhead Data Type / Data Type Offset
# ........................... ............................
#
26.09% 3.28% 0.00% long unsigned int
26.09% 3.28% 0.00% long unsigned int +0 (no field)
18.48% 0.73% 0.00% struct page
10.83% 0.02% 0.00% struct page +8 (lru.next)
3.90% 0.28% 0.00% struct page +0 (flags)
3.45% 0.06% 0.00% struct page +24 (mapping)
0.25% 0.28% 0.00% struct page +48 (_mapcount.counter)
0.02% 0.06% 0.00% struct page +32 (index)
0.02% 0.00% 0.00% struct page +52 (_refcount.counter)
0.02% 0.01% 0.00% struct page +56 (memcg_data)
0.00% 0.01% 0.00% struct page +16 (lru.prev)
15.37% 17.54% 0.00% (stack operation)
15.37% 17.54% 0.00% (stack operation) +0 (no field)
11.71% 50.27% 0.00% (unknown)
11.71% 50.27% 0.00% (unknown) +0 (no field)
$ perf annotate --data-type
...
Annotate type: 'struct cfs_rq' in [kernel.kallsyms] (13 samples):
============================================================================
samples offset size field
13 0 640 struct cfs_rq {
2 0 16 struct load_weight load {
2 0 8 unsigned long weight;
0 8 4 u32 inv_weight;
};
0 16 8 unsigned long runnable_weight;
0 24 4 unsigned int nr_running;
1 28 4 unsigned int h_nr_running;
...
$ perf annotate --data-type=page --group
Annotate type: 'struct page' in [kernel.kallsyms] (480 samples):
event[0] = cpu/mem-loads,ldlat=4/P
event[1] = cpu/mem-stores/P
event[2] = dummy:u
===================================================================================
samples offset size field
447 33 0 0 64 struct page {
108 8 0 0 8 long unsigned int flags;
319 13 0 8 40 union {
319 13 0 8 40 struct {
236 2 0 8 16 union {
236 2 0 8 16 struct list_head lru {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
236 2 0 8 16 struct {
236 1 0 8 8 void* __filler;
0 1 0 16 4 unsigned int mlock_count;
};
236 2 0 8 16 struct list_head buddy_list {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
236 2 0 8 16 struct list_head pcp_list {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
};
82 4 0 24 8 struct address_space* mapping;
1 7 0 32 8 union {
1 7 0 32 8 long unsigned int index;
1 7 0 32 8 long unsigned int share;
};
0 0 0 40 8 long unsigned int private;
};
This uses the existing annotate code, calling objdump to do the disassembly,
with improvements to avoid having this take too long, but longer term a
switch to a disassembler library, possibly reusing code in the kernel will
be pursued.
This is the initial implementation, please use it and report impressions and
bugs. Make sure the kernel-debuginfo packages match the running kernel. The
'perf report' phase for non short perf.data files may take a while.
There is a great article about it on LWN:
https://lwn.net/Articles/955709/ - "Data-type profiling for perf"
One last test I did while writing this text, on a AMD Ryzen 5950X, using a distro
kernel, while doing a simple 'find /' on an otherwise idle system resulted in:
# uname -r
6.6.9-100.fc38.x86_64
# perf -vv | grep BPF_
bpf: [ on ] # HAVE_LIBBPF_SUPPORT
bpf_skeletons: [ on ] # HAVE_BPF_SKEL
# rpm -qa | grep kernel-debuginfo
kernel-debuginfo-common-x86_64-6.6.9-100.fc38.x86_64
kernel-debuginfo-6.6.9-100.fc38.x86_64
#
# perf mem record -a --filter 'mem_op == load || mem_op == store, ip > 0x8000000000000000'
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 2.199 MB perf.data (2913 samples) ]
#
# ls -la perf.data
-rw-------. 1 root root 2346486 Jan 9 18:36 perf.data
# perf evlist
ibs_op//
dummy:u
# perf evlist -v
ibs_op//: type: 11, size: 136, config: 0, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|ADDR|CPU|PERIOD|IDENTIFIER|DATA_SRC|WEIGHT, read_format: ID, disabled: 1, inherit: 1, freq: 1, sample_id_all: 1
dummy:u: type: 1 (PERF_TYPE_SOFTWARE), size: 136, config: 0x9 (PERF_COUNT_SW_DUMMY), { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|ADDR|CPU|IDENTIFIER|DATA_SRC|WEIGHT, read_format: ID, inherit: 1, exclude_kernel: 1, exclude_hv: 1, mmap: 1, comm: 1, task: 1, mmap_data: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1
#
# perf report -s type,typeoff --hierarchy --group --stdio
# Total Lost Samples: 0
#
# Samples: 2K of events 'ibs_op//, dummy:u'
# Event count (approx.): 1904553038
#
# Overhead Data Type / Data Type Offset
# ................... ............................
#
73.70% 0.00% (unknown)
73.70% 0.00% (unknown) +0 (no field)
3.01% 0.00% long unsigned int
3.00% 0.00% long unsigned int +0 (no field)
0.01% 0.00% long unsigned int +2 (no field)
2.73% 0.00% struct task_struct
1.71% 0.00% struct task_struct +52 (on_cpu)
0.38% 0.00% struct task_struct +2104 (rcu_read_unlock_special.b.blocked)
0.23% 0.00% struct task_struct +2100 (rcu_read_lock_nesting)
0.14% 0.00% struct task_struct +2384 ()
0.06% 0.00% struct task_struct +3096 (signal)
0.05% 0.00% struct task_struct +3616 (cgroups)
0.05% 0.00% struct task_struct +2344 (active_mm)
0.02% 0.00% struct task_struct +46 (flags)
0.02% 0.00% struct task_struct +2096 (migration_disabled)
0.01% 0.00% struct task_struct +24 (__state)
0.01% 0.00% struct task_struct +3956 (mm_cid_active)
0.01% 0.00% struct task_struct +1048 (cpus_ptr)
0.01% 0.00% struct task_struct +184 (se.group_node.next)
0.01% 0.00% struct task_struct +20 (thread_info.cpu)
0.00% 0.00% struct task_struct +104 (on_rq)
0.00% 0.00% struct task_struct +2456 (pid)
1.36% 0.00% struct module
0.59% 0.00% struct module +952 (kallsyms)
0.42% 0.00% struct module +0 (state)
0.23% 0.00% struct module +8 (list.next)
0.12% 0.00% struct module +216 (syms)
0.95% 0.00% struct inode
0.41% 0.00% struct inode +40 (i_sb)
0.22% 0.00% struct inode +0 (i_mode)
0.06% 0.00% struct inode +76 (i_rdev)
0.06% 0.00% struct inode +56 (i_security)
<SNIP>
perf top/report:
- Don't ignore job control, allowing control+Z + bg to work.
- Add s390 raw data interpretation for PAI (Processor Activity Instrumentation)
counters.
perf archive:
- Add new option '--all' to pack perf.data with DSOs.
- Add new option '--unpack' to expand tarballs.
Initialization speedups:
- Lazily initialize zstd streams to save memory when not using it.
- Lazily allocate/size mmap event copy.
- Lazy load kernel symbols in 'perf record'.
- Be lazier in allocating lost samples buffer in 'perf record'.
- Don't synthesize BPF events when disabled via the command line (perf record --no-bpf-event).
Assorted improvements:
- Show note on AMD systems that the :p, :pp, :ppp and :P are all the same, as
IBS (Instruction Based Sampling) is used and it is inherentely precise, not
having levels of precision like in Intel systems.
- When 'cycles' isn't available, fall back to the "task-clock" event when not
system wide, not to 'cpu-clock'.
- Add --debug-file option to redirect debug output, e.g.:
$ perf --debug-file /tmp/perf.log record -v true
- Shrink 'struct map' to under one cacheline by avoiding function pointers for
selecting if addresses are identity or DSO relative, and using just a byte for
some boolean struct members.
- Resolve the arch specific strerrno just once to use in perf_env__arch_strerrno().
- Reduce memory for recording PERF_RECORD_LOST_SAMPLES event.
Assorted fixes:
- Fix the default 'perf top' usage on Intel hybrid systems, now it starts with
a browser showing the number of samples for Efficiency (cpu_atom/cycles/P) and
Performance (cpu_core/cycles/P). This behaviour is similar on ARM64, with its
respective set of big.LITTLE processors.
- Fix segfault on build_mem_topology() error path.
- Fix 'perf mem' error on hybrid related to availability of mem event in a PMU.
- Fix missing reference count gets (map, maps) in the db-export code.
- Avoid recursively taking env->bpf_progs.lock in the 'perf_env' code.
- Use the newly introduced maps__for_each_map() to add missing locking around
iteration of 'struct map' entries.
- Parse NOTE segments until the build id is found, don't stop on the first one,
ELF files may have several such NOTE segments.
- Remove 'egrep' usage, its deprecated, use 'grep -E' instead.
- Warn first about missing libelf, not libbpf, that depends on libelf.
- Use alternative to 'find ... -printf' as this isn't supported in busybox.
- Address python 3.6 DeprecationWarning for string scapes.
- Fix memory leak in uniq() in libsubcmd.
- Fix man page formatting for 'perf lock'
- Fix some spelling mistakes.
perf tests:
- Fail shell tests that needs some symbol in perf itself if it is stripped.
These tests check if a symbol is resolved, if some hot function is indeed
detected by profiling, etc.
- The 'perf test sigtrap' test is currently failing on PREEMPT_RT, skip it if
sleeping spinlocks are detected (using BTF) and point to the mailing list
discussion about it. This test is also being skipped on several architectures
(powerpc, s390x, arm and aarch64) due to other pending issues with intruction
breakpoints.
- Adjust test case perf record offcpu profiling tests for s390.
- Fix 'Setup struct perf_event_attr' fails on s390 on z/VM guest, addressing
issues caused by the fallback from cycles to task-clock done in this release.
- Fix mask for VG register in the user-regs test.
- Use shellcheck on 'perf test' shell scripts automatically to make sure changes
don't introduce things it flags as problematic.
- Add option to change objdump binary and allow it to be set via 'perf config'.
- Add basic 'perf script', 'perf list --json" and 'perf diff' tests.
- Basic branch counter support.
- Make DSO tests a suite rather than individual.
- Remove atomics from test_loop to avoid test failures.
- Fix call chain match on powerpc for the record+probe_libc_inet_pton test.
- Improve Intel hybrid tests.
Vendor event files (JSON):
powerpc:
- Update datasource event name to fix duplicate events on IBM's Power10.
- Add PVN for HX-C2000 CPU with Power8 Architecture.
Intel:
- Alderlake/rocketlake metric fixes.
- Update emeraldrapids events to v1.02.
- Update icelakex events to v1.23.
- Update sapphirerapids events to v1.17.
- Add skx, clx, icx and spr upi bandwidth metric.
AMD:
- Add Zen 4 memory controller events.
RISC-V:
- Add StarFive Dubhe-80 and Dubhe-90 JSON files.
https://www.starfivetech.com/en/site/cpu-u
- Add T-HEAD C9xx JSON file.
https://github.com/riscv-software-src/opensbi/blob/master/docs/platform/thead-c9xx.md
ARM64:
- Remove UTF-8 characters from cmn.json, that were causing build failure in some
distros.
- Add core PMU events and metrics for Ampere One X.
- Rename Ampere One's BPU_FLUSH_MEM_FAULT to GPC_FLUSH_MEM_FAULT
libperf:
- Rename several perf_cpu_map constructor names to clarify what they really do.
- Ditto for some other methods, coping with some issues in their semantics,
like perf_cpu_map__empty() -> perf_cpu_map__has_any_cpu_or_is_empty().
- Document perf_cpu_map__nr()'s behavior
perf stat:
- Exit if parse groups fails.
- Combine the -A/--no-aggr and --no-merge options.
- Fix help message for --metric-no-threshold option.
Hardware tracing:
ARM64 CoreSight:
- Bump minimum OpenCSD version to ensure a bugfix is present.
- Add 'T' itrace option for timestamp trace
- Set start vm addr of exectable file to 0 and don't ignore first sample on the
arm-cs-trace-disasm.py 'perf script'.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-tools-for-v6.8-1-2024-01-09' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools
Pull perf tools updates from Arnaldo Carvalho de Melo:
"Add Namhyung Kim as tools/perf/ co-maintainer, we're taking turns
processing patches, switching roles from perf-tools to perf-tools-next
at each Linux release.
Data profiling:
- Associate samples that identify loads and stores with data
structures. This uses events available on Intel, AMD and others and
DWARF info:
# To get memory access samples in kernel for 1 second (on Intel)
$ perf mem record -a -K --ldlat=4 -- sleep 1
# Similar for the AMD (but it requires 6.3+ kernel for BPF filters)
$ perf mem record -a --filter 'mem_op == load || mem_op == store, ip > 0x8000000000000000' -- sleep 1
Then, amongst several modes of post processing, one can do things like:
$ perf report -s type,typeoff --hierarchy --group --stdio
...
#
# Samples: 10K of events 'cpu/mem-loads,ldlat=4/P, cpu/mem-stores/P, dummy:u'
# Event count (approx.): 602758064
#
# Overhead Data Type / Data Type Offset
# ........................... ............................
#
26.09% 3.28% 0.00% long unsigned int
26.09% 3.28% 0.00% long unsigned int +0 (no field)
18.48% 0.73% 0.00% struct page
10.83% 0.02% 0.00% struct page +8 (lru.next)
3.90% 0.28% 0.00% struct page +0 (flags)
3.45% 0.06% 0.00% struct page +24 (mapping)
0.25% 0.28% 0.00% struct page +48 (_mapcount.counter)
0.02% 0.06% 0.00% struct page +32 (index)
0.02% 0.00% 0.00% struct page +52 (_refcount.counter)
0.02% 0.01% 0.00% struct page +56 (memcg_data)
0.00% 0.01% 0.00% struct page +16 (lru.prev)
15.37% 17.54% 0.00% (stack operation)
15.37% 17.54% 0.00% (stack operation) +0 (no field)
11.71% 50.27% 0.00% (unknown)
11.71% 50.27% 0.00% (unknown) +0 (no field)
$ perf annotate --data-type
...
Annotate type: 'struct cfs_rq' in [kernel.kallsyms] (13 samples):
============================================================================
samples offset size field
13 0 640 struct cfs_rq {
2 0 16 struct load_weight load {
2 0 8 unsigned long weight;
0 8 4 u32 inv_weight;
};
0 16 8 unsigned long runnable_weight;
0 24 4 unsigned int nr_running;
1 28 4 unsigned int h_nr_running;
...
$ perf annotate --data-type=page --group
Annotate type: 'struct page' in [kernel.kallsyms] (480 samples):
event[0] = cpu/mem-loads,ldlat=4/P
event[1] = cpu/mem-stores/P
event[2] = dummy:u
===================================================================================
samples offset size field
447 33 0 0 64 struct page {
108 8 0 0 8 long unsigned int flags;
319 13 0 8 40 union {
319 13 0 8 40 struct {
236 2 0 8 16 union {
236 2 0 8 16 struct list_head lru {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
236 2 0 8 16 struct {
236 1 0 8 8 void* __filler;
0 1 0 16 4 unsigned int mlock_count;
};
236 2 0 8 16 struct list_head buddy_list {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
236 2 0 8 16 struct list_head pcp_list {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
};
82 4 0 24 8 struct address_space* mapping;
1 7 0 32 8 union {
1 7 0 32 8 long unsigned int index;
1 7 0 32 8 long unsigned int share;
};
0 0 0 40 8 long unsigned int private;
};
This uses the existing annotate code, calling objdump to do the
disassembly, with improvements to avoid having this take too long,
but longer term a switch to a disassembler library, possibly
reusing code in the kernel will be pursued.
This is the initial implementation, please use it and report
impressions and bugs. Make sure the kernel-debuginfo packages match
the running kernel. The 'perf report' phase for non short perf.data
files may take a while.
There is a great article about it on LWN:
https://lwn.net/Articles/955709/ - "Data-type profiling for perf"
One last test I did while writing this text, on a AMD Ryzen 5950X,
using a distro kernel, while doing a simple 'find /' on an
otherwise idle system resulted in:
# uname -r
6.6.9-100.fc38.x86_64
# perf -vv | grep BPF_
bpf: [ on ] # HAVE_LIBBPF_SUPPORT
bpf_skeletons: [ on ] # HAVE_BPF_SKEL
# rpm -qa | grep kernel-debuginfo
kernel-debuginfo-common-x86_64-6.6.9-100.fc38.x86_64
kernel-debuginfo-6.6.9-100.fc38.x86_64
#
# perf mem record -a --filter 'mem_op == load || mem_op == store, ip > 0x8000000000000000'
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 2.199 MB perf.data (2913 samples) ]
#
# ls -la perf.data
-rw-------. 1 root root 2346486 Jan 9 18:36 perf.data
# perf evlist
ibs_op//
dummy:u
# perf evlist -v
ibs_op//: type: 11, size: 136, config: 0, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|ADDR|CPU|PERIOD|IDENTIFIER|DATA_SRC|WEIGHT, read_format: ID, disabled: 1, inherit: 1, freq: 1, sample_id_all: 1
dummy:u: type: 1 (PERF_TYPE_SOFTWARE), size: 136, config: 0x9 (PERF_COUNT_SW_DUMMY), { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|ADDR|CPU|IDENTIFIER|DATA_SRC|WEIGHT, read_format: ID, inherit: 1, exclude_kernel: 1, exclude_hv: 1, mmap: 1, comm: 1, task: 1, mmap_data: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1
#
# perf report -s type,typeoff --hierarchy --group --stdio
# Total Lost Samples: 0
#
# Samples: 2K of events 'ibs_op//, dummy:u'
# Event count (approx.): 1904553038
#
# Overhead Data Type / Data Type Offset
# ................... ............................
#
73.70% 0.00% (unknown)
73.70% 0.00% (unknown) +0 (no field)
3.01% 0.00% long unsigned int
3.00% 0.00% long unsigned int +0 (no field)
0.01% 0.00% long unsigned int +2 (no field)
2.73% 0.00% struct task_struct
1.71% 0.00% struct task_struct +52 (on_cpu)
0.38% 0.00% struct task_struct +2104 (rcu_read_unlock_special.b.blocked)
0.23% 0.00% struct task_struct +2100 (rcu_read_lock_nesting)
0.14% 0.00% struct task_struct +2384 ()
0.06% 0.00% struct task_struct +3096 (signal)
0.05% 0.00% struct task_struct +3616 (cgroups)
0.05% 0.00% struct task_struct +2344 (active_mm)
0.02% 0.00% struct task_struct +46 (flags)
0.02% 0.00% struct task_struct +2096 (migration_disabled)
0.01% 0.00% struct task_struct +24 (__state)
0.01% 0.00% struct task_struct +3956 (mm_cid_active)
0.01% 0.00% struct task_struct +1048 (cpus_ptr)
0.01% 0.00% struct task_struct +184 (se.group_node.next)
0.01% 0.00% struct task_struct +20 (thread_info.cpu)
0.00% 0.00% struct task_struct +104 (on_rq)
0.00% 0.00% struct task_struct +2456 (pid)
1.36% 0.00% struct module
0.59% 0.00% struct module +952 (kallsyms)
0.42% 0.00% struct module +0 (state)
0.23% 0.00% struct module +8 (list.next)
0.12% 0.00% struct module +216 (syms)
0.95% 0.00% struct inode
0.41% 0.00% struct inode +40 (i_sb)
0.22% 0.00% struct inode +0 (i_mode)
0.06% 0.00% struct inode +76 (i_rdev)
0.06% 0.00% struct inode +56 (i_security)
<SNIP>
perf top/report:
- Don't ignore job control, allowing control+Z + bg to work.
- Add s390 raw data interpretation for PAI (Processor Activity
Instrumentation) counters.
perf archive:
- Add new option '--all' to pack perf.data with DSOs.
- Add new option '--unpack' to expand tarballs.
Initialization speedups:
- Lazily initialize zstd streams to save memory when not using it.
- Lazily allocate/size mmap event copy.
- Lazy load kernel symbols in 'perf record'.
- Be lazier in allocating lost samples buffer in 'perf record'.
- Don't synthesize BPF events when disabled via the command line
(perf record --no-bpf-event).
Assorted improvements:
- Show note on AMD systems that the :p, :pp, :ppp and :P are all the
same, as IBS (Instruction Based Sampling) is used and it is
inherentely precise, not having levels of precision like in Intel
systems.
- When 'cycles' isn't available, fall back to the "task-clock" event
when not system wide, not to 'cpu-clock'.
- Add --debug-file option to redirect debug output, e.g.:
$ perf --debug-file /tmp/perf.log record -v true
- Shrink 'struct map' to under one cacheline by avoiding function
pointers for selecting if addresses are identity or DSO relative,
and using just a byte for some boolean struct members.
- Resolve the arch specific strerrno just once to use in
perf_env__arch_strerrno().
- Reduce memory for recording PERF_RECORD_LOST_SAMPLES event.
Assorted fixes:
- Fix the default 'perf top' usage on Intel hybrid systems, now it
starts with a browser showing the number of samples for Efficiency
(cpu_atom/cycles/P) and Performance (cpu_core/cycles/P). This
behaviour is similar on ARM64, with its respective set of
big.LITTLE processors.
- Fix segfault on build_mem_topology() error path.
- Fix 'perf mem' error on hybrid related to availability of mem event
in a PMU.
- Fix missing reference count gets (map, maps) in the db-export code.
- Avoid recursively taking env->bpf_progs.lock in the 'perf_env'
code.
- Use the newly introduced maps__for_each_map() to add missing
locking around iteration of 'struct map' entries.
- Parse NOTE segments until the build id is found, don't stop on the
first one, ELF files may have several such NOTE segments.
- Remove 'egrep' usage, its deprecated, use 'grep -E' instead.
- Warn first about missing libelf, not libbpf, that depends on
libelf.
- Use alternative to 'find ... -printf' as this isn't supported in
busybox.
- Address python 3.6 DeprecationWarning for string scapes.
- Fix memory leak in uniq() in libsubcmd.
- Fix man page formatting for 'perf lock'
- Fix some spelling mistakes.
perf tests:
- Fail shell tests that needs some symbol in perf itself if it is
stripped. These tests check if a symbol is resolved, if some hot
function is indeed detected by profiling, etc.
- The 'perf test sigtrap' test is currently failing on PREEMPT_RT,
skip it if sleeping spinlocks are detected (using BTF) and point to
the mailing list discussion about it. This test is also being
skipped on several architectures (powerpc, s390x, arm and aarch64)
due to other pending issues with intruction breakpoints.
- Adjust test case perf record offcpu profiling tests for s390.
- Fix 'Setup struct perf_event_attr' fails on s390 on z/VM guest,
addressing issues caused by the fallback from cycles to task-clock
done in this release.
- Fix mask for VG register in the user-regs test.
- Use shellcheck on 'perf test' shell scripts automatically to make
sure changes don't introduce things it flags as problematic.
- Add option to change objdump binary and allow it to be set via
'perf config'.
- Add basic 'perf script', 'perf list --json" and 'perf diff' tests.
- Basic branch counter support.
- Make DSO tests a suite rather than individual.
- Remove atomics from test_loop to avoid test failures.
- Fix call chain match on powerpc for the record+probe_libc_inet_pton
test.
- Improve Intel hybrid tests.
Vendor event files (JSON):
powerpc:
- Update datasource event name to fix duplicate events on IBM's
Power10.
- Add PVN for HX-C2000 CPU with Power8 Architecture.
Intel:
- Alderlake/rocketlake metric fixes.
- Update emeraldrapids events to v1.02.
- Update icelakex events to v1.23.
- Update sapphirerapids events to v1.17.
- Add skx, clx, icx and spr upi bandwidth metric.
AMD:
- Add Zen 4 memory controller events.
RISC-V:
- Add StarFive Dubhe-80 and Dubhe-90 JSON files.
https://www.starfivetech.com/en/site/cpu-u
- Add T-HEAD C9xx JSON file.
https://github.com/riscv-software-src/opensbi/blob/master/docs/platform/thead-c9xx.md
ARM64:
- Remove UTF-8 characters from cmn.json, that were causing build
failure in some distros.
- Add core PMU events and metrics for Ampere One X.
- Rename Ampere One's BPU_FLUSH_MEM_FAULT to GPC_FLUSH_MEM_FAULT
libperf:
- Rename several perf_cpu_map constructor names to clarify what they
really do.
- Ditto for some other methods, coping with some issues in their
semantics, like perf_cpu_map__empty() ->
perf_cpu_map__has_any_cpu_or_is_empty().
- Document perf_cpu_map__nr()'s behavior
perf stat:
- Exit if parse groups fails.
- Combine the -A/--no-aggr and --no-merge options.
- Fix help message for --metric-no-threshold option.
Hardware tracing:
ARM64 CoreSight:
- Bump minimum OpenCSD version to ensure a bugfix is present.
- Add 'T' itrace option for timestamp trace
- Set start vm addr of exectable file to 0 and don't ignore first
sample on the arm-cs-trace-disasm.py 'perf script'"
* tag 'perf-tools-for-v6.8-1-2024-01-09' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (179 commits)
MAINTAINERS: Add Namhyung as tools/perf/ co-maintainer
perf test: test case 'Setup struct perf_event_attr' fails on s390 on z/vm
perf db-export: Fix missing reference count get in call_path_from_sample()
perf tests: Add perf script test
libsubcmd: Fix memory leak in uniq()
perf TUI: Don't ignore job control
perf vendor events intel: Update sapphirerapids events to v1.17
perf vendor events intel: Update icelakex events to v1.23
perf vendor events intel: Update emeraldrapids events to v1.02
perf vendor events intel: Alderlake/rocketlake metric fixes
perf x86 test: Add hybrid test for conflicting legacy/sysfs event
perf x86 test: Update hybrid expectations
perf vendor events amd: Add Zen 4 memory controller events
perf stat: Fix hard coded LL miss units
perf record: Reduce memory for recording PERF_RECORD_LOST_SAMPLES event
perf env: Avoid recursively taking env->bpf_progs.lock
perf annotate: Add --insn-stat option for debugging
perf annotate: Add --type-stat option for debugging
perf annotate: Support event group display
perf annotate: Add --data-type option
...
|
||
|
Andrii Nakryiko
|
76ec90a996 |
libbpf: warn on unexpected __arg_ctx type when rewriting BTF
On kernel that don't support arg:ctx tag, before adjusting global subprog BTF information to match kernel's expected canonical type names, make sure that types used by user are meaningful, and if not, warn and don't do BTF adjustments. This is similar to checks that kernel performs, but narrower in scope, as only a small subset of BPF program types can be accommodated by libbpf using canonical type names. Libbpf unconditionally allows `struct pt_regs *` for perf_event program types, unlike kernel, which supports that conditionally on architecture. This is done to keep things simple and not cause unnecessary false positives. This seems like a minor and harmless deviation, which in real-world programs will be caught by kernels with arg:ctx tag support anyways. So KISS principle. This logic is hard to test (especially on latest kernels), so manual testing was performed instead. Libbpf emitted the following warning for perf_event program with wrong context argument type: libbpf: prog 'arg_tag_ctx_perf': subprog 'subprog_ctx_tag' arg#0 is expected to be of `struct bpf_perf_event_data *` type Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240118033143.3384355-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
01b55f4f0c |
libbpf: feature-detect arg:ctx tag support in kernel
Add feature detector of kernel-side arg:ctx (__arg_ctx) tag support. If this is detected, libbpf will avoid doing any __arg_ctx-related BTF rewriting and checks in favor of letting kernel handle this completely. test_global_funcs/ctx_arg_rewrite subtest is adjusted to do the same feature detection (albeit in much simpler, though round-about and inefficient, way), and skip the tests. This is done to still be able to execute this test on older kernels (like in libbpf CI). Note, BPF token series ([0]) does a major refactor and code moving of libbpf-internal feature detection "framework", so to avoid unnecessary conflicts we keep newly added feature detection stand-alone with ad-hoc result caching. Once things settle, there will be a small follow up to re-integrate everything back and move code into its final place in newly-added (by BPF token series) features.c file. [0] https://patchwork.kernel.org/project/netdevbpf/list/?series=814209&state=* Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240118033143.3384355-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
Ian Rogers
|
ad30469a84 |
libsubcmd: Fix memory leak in uniq()
uniq() will write one command name over another causing the overwritten string to be leaked. Fix by doing a pass that removes duplicates and a second that removes the holes. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Chenyuan Mi <cymi20@fudan.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20231208000515.1693746-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Andrii Nakryiko
|
2f38fe6894 |
libbpf: implement __arg_ctx fallback logic
Out of all special global func arg tag annotations, __arg_ctx is
practically is the most immediately useful and most critical to have
working across multitude kernel version, if possible. This would allow
end users to write much simpler code if __arg_ctx semantics worked for
older kernels that don't natively understand btf_decl_tag("arg:ctx") in
verifier logic.
Luckily, it is possible to ensure __arg_ctx works on old kernels through
a bit of extra work done by libbpf, at least in a lot of common cases.
To explain the overall idea, we need to go back at how context argument
was supported in global funcs before __arg_ctx support was added. This
was done based on special struct name checks in kernel. E.g., for
BPF_PROG_TYPE_PERF_EVENT the expectation is that argument type `struct
bpf_perf_event_data *` mark that argument as PTR_TO_CTX. This is all
good as long as global function is used from the same BPF program types
only, which is often not the case. If the same subprog has to be called
from, say, kprobe and perf_event program types, there is no single
definition that would satisfy BPF verifier. Subprog will have context
argument either for kprobe (if using bpf_user_pt_regs_t struct name) or
perf_event (with bpf_perf_event_data struct name), but not both.
This limitation was the reason to add btf_decl_tag("arg:ctx"), making
the actual argument type not important, so that user can just define
"generic" signature:
__noinline int global_subprog(void *ctx __arg_ctx) { ... }
I won't belabor how libbpf is implementing subprograms, see a huge
comment next to bpf_object_relocate_calls() function. The idea is that
each main/entry BPF program gets its own copy of global_subprog's code
appended.
This per-program copy of global subprog code *and* associated func_info
.BTF.ext information, pointing to FUNC -> FUNC_PROTO BTF type chain
allows libbpf to simulate __arg_ctx behavior transparently, even if the
kernel doesn't yet support __arg_ctx annotation natively.
The idea is straightforward: each time we append global subprog's code
and func_info information, we adjust its FUNC -> FUNC_PROTO type
information, if necessary (that is, libbpf can detect the presence of
btf_decl_tag("arg:ctx") just like BPF verifier would do it).
The rest is just mechanical and somewhat painful BTF manipulation code.
It's painful because we need to clone FUNC -> FUNC_PROTO, instead of
reusing it, as same FUNC -> FUNC_PROTO chain might be used by another
main BPF program within the same BPF object, so we can't just modify it
in-place (and cloning BTF types within the same struct btf object is
painful due to constant memory invalidation, see comments in code).
Uploaded BPF object's BTF information has to work for all BPF
programs at the same time.
Once we have FUNC -> FUNC_PROTO clones, we make sure that instead of
using some `void *ctx` parameter definition, we have an expected `struct
bpf_perf_event_data *ctx` definition (as far as BPF verifier and kernel
is concerned), which will mark it as context for BPF verifier. Same
global subprog relocated and copied into another main BPF program will
get different type information according to main program's type. It all
works out in the end in a completely transparent way for end user.
Libbpf maintains internal program type -> expected context struct name
mapping internally. Note, not all BPF program types have named context
struct, so this approach won't work for such programs (just like it
didn't before __arg_ctx). So native __arg_ctx is still important to have
in kernel to have generic context support across all BPF program types.
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240104013847.3875810-8-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
||
|
Andrii Nakryiko
|
1004742d7f |
libbpf: move BTF loading step after relocation step
With all the preparations in previous patches done we are ready to postpone BTF loading and sanitization step until after all the relocations are performed. Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-7-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
fb03be7c4a |
libbpf: move exception callbacks assignment logic into relocation step
Move the logic of finding and assigning exception callback indices from BTF sanitization step to program relocations step, which seems more logical and will unblock moving BTF loading to after relocation step. Exception callbacks discovery and assignment has no dependency on BTF being loaded into the kernel, it only uses BTF information. It does need to happen before subprogram relocations happen, though. Which is why the split. No functional changes. Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
dac645b950 |
libbpf: use stable map placeholder FDs
Move map creation to later during BPF object loading by pre-creating stable placeholder FDs (utilizing memfd_create()). Use dup2() syscall to then atomically make those placeholder FDs point to real kernel BPF map objects. This change allows to delay BPF map creation to after all the BPF program relocations. That, in turn, allows to delay BTF finalization and loading into kernel to after all the relocations as well. We'll take advantage of the latter in subsequent patches to allow libbpf to adjust BTF in a way that helps with BPF global function usage. Clean up a few places where we close map->fd, which now shouldn't happen, because map->fd should be a valid FD regardless of whether map was created or not. Surprisingly and nicely it simplifies a bunch of error handling code. If this change doesn't backfire, I'm tempted to pre-create such stable FDs for other entities (progs, maybe even BTF). We previously did some manipulations to make gen_loader work with fake map FDs, with stable map FDs this hack is not necessary for maps (we still have it for BTF, but I left it as is for now). Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
f08c18e083 |
libbpf: don't rely on map->fd as an indicator of map being created
With the upcoming switch to preallocated placeholder FDs for maps, switch various getters/setter away from checking map->fd. Use map_is_created() helper that detect whether BPF map can be modified based on map->obj->loaded state, with special provision for maps set up with bpf_map__reuse_fd(). For backwards compatibility, we take map_is_created() into account in bpf_map__fd() getter as well. This way before bpf_object__load() phase bpf_map__fd() will always return -1, just as before the changes in subsequent patches adding stable map->fd placeholders. We also get rid of all internal uses of bpf_map__fd() getter, as it's more oriented for uses external to libbpf. The above map_is_created() check actually interferes with some of the internal uses, if map FD is fetched through bpf_map__fd(). Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
fa98b54bff |
libbpf: use explicit map reuse flag to skip map creation steps
Instead of inferring whether map already point to previously created/pinned BPF map (which user can specify with bpf_map__reuse_fd()) API), use explicit map->reused flag that is set in such case. Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
df7c3f7d3a |
libbpf: make uniform use of btf__fd() accessor inside libbpf
It makes future grepping and code analysis a bit easier. Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
Mingyi Zhang
|
fc3a5534e2 |
libbpf: Fix NULL pointer dereference in bpf_object__collect_prog_relos
An issue occurred while reading an ELF file in libbpf.c during fuzzing: Program received signal SIGSEGV, Segmentation fault. 0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206 4206 in libbpf.c (gdb) bt #0 0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206 #1 0x000000000094f9d6 in bpf_object.collect_relos () at libbpf.c:6706 #2 0x000000000092bef3 in bpf_object_open () at libbpf.c:7437 #3 0x000000000092c046 in bpf_object.open_mem () at libbpf.c:7497 #4 0x0000000000924afa in LLVMFuzzerTestOneInput () at fuzz/bpf-object-fuzzer.c:16 #5 0x000000000060be11 in testblitz_engine::fuzzer::Fuzzer::run_one () #6 0x000000000087ad92 in tracing::span::Span::in_scope () #7 0x00000000006078aa in testblitz_engine::fuzzer::util::walkdir () #8 0x00000000005f3217 in testblitz_engine::entrypoint::main::{{closure}} () #9 0x00000000005f2601 in main () (gdb) scn_data was null at this code(tools/lib/bpf/src/libbpf.c): if (rel->r_offset % BPF_INSN_SZ || rel->r_offset >= scn_data->d_size) { The scn_data is derived from the code above: scn = elf_sec_by_idx(obj, sec_idx); scn_data = elf_sec_data(obj, scn); relo_sec_name = elf_sec_str(obj, shdr->sh_name); sec_name = elf_sec_name(obj, scn); if (!relo_sec_name || !sec_name)// don't check whether scn_data is NULL return -EINVAL; In certain special scenarios, such as reading a malformed ELF file, it is possible that scn_data may be a null pointer Signed-off-by: Mingyi Zhang <zhangmingyi5@huawei.com> Signed-off-by: Xin Liu <liuxin350@huawei.com> Signed-off-by: Changye Wu <wuchangye@huawei.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20231221033947.154564-1-liuxin350@huawei.com |
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Alyssa Ross
|
812d8bf876 |
libbpf: Skip DWARF sections in linker sanity check
clang can generate (with -g -Wa,--compress-debug-sections) 4-byte aligned DWARF sections that declare themselves to be 8-byte aligned in the section header. Since DWARF sections are dropped during linking anyway, just skip running the sanity checks on them. Reported-by: Sergei Trofimovich <slyich@gmail.com> Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com> Signed-off-by: Alyssa Ross <hi@alyssa.is> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Closes: https://lore.kernel.org/bpf/ZXcFRJVKbKxtEL5t@nz.home/ Link: https://lore.kernel.org/bpf/20231219110324.8989-1-hi@alyssa.is |
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Andrii Nakryiko
|
aae9c25dda |
libbpf: add __arg_xxx macros for annotating global func args
Add a set of __arg_xxx macros which can be used to augment BPF global subprogs/functions with extra information for use by BPF verifier. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231215011334.2307144-9-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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Andrii Nakryiko
|
d17aff807f |
Revert BPF token-related functionality
This patch includes the following revert (one conflicting BPF FS patch and three token patch sets, represented by merge commits): - revert |
||
Arnaldo Carvalho de Melo
|
ab1c247094 |
Merge remote-tracking branch 'torvalds/master' into perf-tools-next
To pick up fixes that went thru perf-tools for v6.7 and to get in sync with upstream to check for drift in the copies of headers, etc. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Ian Rogers
|
67bc993446 |
libperf cpumap: Document perf_cpu_map__nr()'s behavior
perf_cpu_map__nr()'s behavior around an empty CPU map is strange as it returns that there is 1 CPU. Changing code that may rely on this behavior is hard, we can at least document the behavior. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Link: https://lore.kernel.org/r/20231129060211.1890454-15-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Andrii Nakryiko
|
ed54124b88 |
libbpf: support BPF token path setting through LIBBPF_BPF_TOKEN_PATH envvar
To allow external admin authority to override default BPF FS location (/sys/fs/bpf) for implicit BPF token creation, teach libbpf to recognize LIBBPF_BPF_TOKEN_PATH envvar. If it is specified and user application didn't explicitly specify neither bpf_token_path nor bpf_token_fd option, it will be treated exactly like bpf_token_path option, overriding default /sys/fs/bpf location and making BPF token mandatory. Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231213190842.3844987-10-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
1d0dd6ea2e |
libbpf: wire up BPF token support at BPF object level
Add BPF token support to BPF object-level functionality.
BPF token is supported by BPF object logic either as an explicitly
provided BPF token from outside (through BPF FS path or explicit BPF
token FD), or implicitly (unless prevented through
bpf_object_open_opts).
Implicit mode is assumed to be the most common one for user namespaced
unprivileged workloads. The assumption is that privileged container
manager sets up default BPF FS mount point at /sys/fs/bpf with BPF token
delegation options (delegate_{cmds,maps,progs,attachs} mount options).
BPF object during loading will attempt to create BPF token from
/sys/fs/bpf location, and pass it for all relevant operations
(currently, map creation, BTF load, and program load).
In this implicit mode, if BPF token creation fails due to whatever
reason (BPF FS is not mounted, or kernel doesn't support BPF token,
etc), this is not considered an error. BPF object loading sequence will
proceed with no BPF token.
In explicit BPF token mode, user provides explicitly either custom BPF
FS mount point path or creates BPF token on their own and just passes
token FD directly. In such case, BPF object will either dup() token FD
(to not require caller to hold onto it for entire duration of BPF object
lifetime) or will attempt to create BPF token from provided BPF FS
location. If BPF token creation fails, that is considered a critical
error and BPF object load fails with an error.
Libbpf provides a way to disable implicit BPF token creation, if it
causes any troubles (BPF token is designed to be completely optional and
shouldn't cause any problems even if provided, but in the world of BPF
LSM, custom security logic can be installed that might change outcome
dependin on the presence of BPF token). To disable libbpf's default BPF
token creation behavior user should provide either invalid BPF token FD
(negative), or empty bpf_token_path option.
BPF token presence can influence libbpf's feature probing, so if BPF
object has associated BPF token, feature probing is instructed to use
BPF object-specific feature detection cache and token FD.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231213190842.3844987-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
||
|
Andrii Nakryiko
|
a75bb6a165 |
libbpf: wire up token_fd into feature probing logic
Adjust feature probing callbacks to take into account optional token_fd. In unprivileged contexts, some feature detectors would fail to detect kernel support just because BPF program, BPF map, or BTF object can't be loaded due to privileged nature of those operations. So when BPF object is loaded with BPF token, this token should be used for feature probing. This patch is setting support for this scenario, but we don't yet pass non-zero token FD. This will be added in the next patch. We also switched BPF cookie detector from using kprobe program to tracepoint one, as tracepoint is somewhat less dangerous BPF program type and has higher likelihood of being allowed through BPF token in the future. This change has no effect on detection behavior. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231213190842.3844987-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
ab8fc393b2 |
libbpf: move feature detection code into its own file
It's quite a lot of well isolated code, so it seems like a good candidate to move it out of libbpf.c to reduce its size. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231213190842.3844987-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
29c302a2e2 |
libbpf: further decouple feature checking logic from bpf_object
Add feat_supported() helper that accepts feature cache instead of bpf_object. This allows low-level code in bpf.c to not know or care about higher-level concept of bpf_object, yet it will be able to utilize custom feature checking in cases where BPF token might influence the outcome. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231213190842.3844987-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
c6c5be3eee |
libbpf: split feature detectors definitions from cached results
Split a list of supported feature detectors with their corresponding callbacks from actual cached supported/missing values. This will allow to have more flexible per-token or per-object feature detectors in subsequent refactorings. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231213190842.3844987-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
Daniel Xu
|
2f70803532 |
libbpf: Add BPF_CORE_WRITE_BITFIELD() macro
=== Motivation ===
Similar to reading from CO-RE bitfields, we need a CO-RE aware bitfield
writing wrapper to make the verifier happy.
Two alternatives to this approach are:
1. Use the upcoming `preserve_static_offset` [0] attribute to disable
CO-RE on specific structs.
2. Use broader byte-sized writes to write to bitfields.
(1) is a bit hard to use. It requires specific and not-very-obvious
annotations to bpftool generated vmlinux.h. It's also not generally
available in released LLVM versions yet.
(2) makes the code quite hard to read and write. And especially if
BPF_CORE_READ_BITFIELD() is already being used, it makes more sense to
to have an inverse helper for writing.
=== Implementation details ===
Since the logic is a bit non-obvious, I thought it would be helpful
to explain exactly what's going on.
To start, it helps by explaining what LSHIFT_U64 (lshift) and RSHIFT_U64
(rshift) is designed to mean. Consider the core of the
BPF_CORE_READ_BITFIELD() algorithm:
val <<= __CORE_RELO(s, field, LSHIFT_U64);
val = val >> __CORE_RELO(s, field, RSHIFT_U64);
Basically what happens is we lshift to clear the non-relevant (blank)
higher order bits. Then we rshift to bring the relevant bits (bitfield)
down to LSB position (while also clearing blank lower order bits). To
illustrate:
Start: ........XXX......
Lshift: XXX......00000000
Rshift: 00000000000000XXX
where `.` means blank bit, `0` means 0 bit, and `X` means bitfield bit.
After the two operations, the bitfield is ready to be interpreted as a
regular integer.
Next, we want to build an alternative (but more helpful) mental model
on lshift and rshift. That is, to consider:
* rshift as the total number of blank bits in the u64
* lshift as number of blank bits left of the bitfield in the u64
Take a moment to consider why that is true by consulting the above
diagram.
With this insight, we can now define the following relationship:
bitfield
_
| |
0.....00XXX0...00
| | | |
|______| | |
lshift | |
|____|
(rshift - lshift)
That is, we know the number of higher order blank bits is just lshift.
And the number of lower order blank bits is (rshift - lshift).
Finally, we can examine the core of the write side algorithm:
mask = (~0ULL << rshift) >> lshift; // 1
val = (val & ~mask) | ((nval << rpad) & mask); // 2
1. Compute a mask where the set bits are the bitfield bits. The first
left shift zeros out exactly the number of blank bits, leaving a
bitfield sized set of 1s. The subsequent right shift inserts the
correct amount of higher order blank bits.
2. On the left of the `|`, mask out the bitfield bits. This creates
0s where the new bitfield bits will go. On the right of the `|`,
bring nval into the correct bit position and mask out any bits
that fall outside of the bitfield. Finally, by bor'ing the two
halves, we get the final set of bits to write back.
[0]: https://reviews.llvm.org/D133361
Co-developed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Co-developed-by: Jonathan Lemon <jlemon@aviatrix.com>
Signed-off-by: Jonathan Lemon <jlemon@aviatrix.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Link: https://lore.kernel.org/r/4d3dd215a4fd57d980733886f9c11a45e1a9adf3.1702325874.git.dxu@dxuuu.xyz
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
|
||
|
Ian Rogers
|
5805c82513 |
libperf cpumap: Add for_each_cpu() that skips the "any CPU" case
When iterating CPUs in a CPU map it is often desirable to skip the "any CPU" (aka dummy) case. Add a helper for this and use in builtin-record. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20231129060211.1890454-6-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Ian Rogers
|
effe957c6b |
libperf cpumap: Replace usage of perf_cpu_map__new(NULL) with perf_cpu_map__new_online_cpus()
Passing NULL to perf_cpu_map__new() performs perf_cpu_map__new_online_cpus(), just directly call perf_cpu_map__new_online_cpus() to be more intention revealing. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20231129060211.1890454-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Ian Rogers
|
923ca62a7b |
libperf cpumap: Rename perf_cpu_map__empty() to perf_cpu_map__has_any_cpu_or_is_empty()
The name perf_cpu_map_empty is misleading as true is also returned when the map contains an "any" CPU (aka dummy) map. Rename to perf_cpu_map__has_any_cpu_or_is_empty(), later changes will (re)introduce perf_cpu_map__empty() and perf_cpu_map__has_any_cpu(). Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20231129060211.1890454-4-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Ian Rogers
|
8f60f870a9 |
libperf cpumap: Rename perf_cpu_map__default_new() to perf_cpu_map__new_online_cpus() and prefer sysfs
Rename perf_cpu_map__default_new() to perf_cpu_map__new_online_cpus() to better indicate what the implementation does. Read the online CPUs from /sys/devices/system/cpu/online first before using sysconf() as it can't accurately configure holes in the CPU map. If sysconf() is used, warn when the configured and online processors disagree. When reading from a file, if the read doesn't yield a CPU map then return an empty map rather than the default online. This avoids recursion but also better yields being able to detect failures. Add more comments. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20231129060211.1890454-3-irogers@google.com [ s/syfs/sysfs/g typo ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Ian Rogers
|
48219b089d |
libperf cpumap: Rename perf_cpu_map__dummy_new() to perf_cpu_map__new_any_cpu()
Rename perf_cpu_map__dummy_new() to perf_cpu_map__new_any_cpu() to better indicate this is creating a CPU map for the perf_event_open "any" CPU case. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20231129060211.1890454-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
Sergei Trofimovich
|
32fa058398 |
libbpf: Add pr_warn() for EINVAL cases in linker_sanity_check_elf
Before the change on `i686-linux` `systemd` build failed as:
$ bpftool gen object src/core/bpf/socket_bind/socket-bind.bpf.o src/core/bpf/socket_bind/socket-bind.bpf.unstripped.o
Error: failed to link 'src/core/bpf/socket_bind/socket-bind.bpf.unstripped.o': Invalid argument (22)
After the change it fails as:
$ bpftool gen object src/core/bpf/socket_bind/socket-bind.bpf.o src/core/bpf/socket_bind/socket-bind.bpf.unstripped.o
libbpf: ELF section #9 has inconsistent alignment addr=8 != d=4 in src/core/bpf/socket_bind/socket-bind.bpf.unstripped.o
Error: failed to link 'src/core/bpf/socket_bind/socket-bind.bpf.unstripped.o': Invalid argument (22)
Now it's slightly easier to figure out what is wrong with an ELF file.
Signed-off-by: Sergei Trofimovich <slyich@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20231208215100.435876-1-slyich@gmail.com
|
||
David Vernet
|
8b7b0e5fe4 |
bpf: Load vmlinux btf for any struct_ops map
In libbpf, when determining whether we need to load vmlinux btf, we're
currently (among other things) checking whether there is any struct_ops
program present in the object. This works for most realistic struct_ops
maps, as a struct_ops map is of course typically composed of one or more
struct_ops programs. However, that technically need not be the case. A
struct_ops interface could be defined which allows a map to be specified
which one or more non-prog fields, and which provides default behavior
if no struct_ops progs is actually provided otherwise. For sched_ext,
for example, you technically only need to specify the name of the
scheduler in the struct_ops map, with the core scheduler logic providing
default behavior if no prog is actually specified.
If we were to define and try to load such a struct_ops map, we would
crash in libbpf when initializing it as obj->btf_vmlinux will be NULL:
Reading symbols from minimal...
(gdb) r
Starting program: minimal_example
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
Program received signal SIGSEGV, Segmentation fault.
0x000055555558308c in btf__type_cnt (btf=0x0) at btf.c:612
612 return btf->start_id + btf->nr_types;
(gdb) bt
type_name=0x5555555d99e3 "sched_ext_ops", kind=4) at btf.c:914
kind=4) at btf.c:942
type=0x7fffffffe558, type_id=0x7fffffffe548, ...
data_member=0x7fffffffe568) at libbpf.c:948
kern_btf=0x0) at libbpf.c:1017
at libbpf.c:8059
So as to account for such bare-bones struct_ops maps, let's update
obj_needs_vmlinux_btf() to also iterate over an obj's maps and check
whether any of them are struct_ops maps.
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20231208061704.400463-1-void@manifault.com
|
||
|
Andrii Nakryiko
|
1571740a9b |
libbpf: add BPF token support to bpf_prog_load() API
Wire through token_fd into bpf_prog_load(). Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-16-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
1a8df7fa00 |
libbpf: add BPF token support to bpf_btf_load() API
Allow user to specify token_fd for bpf_btf_load() API that wraps kernel's BPF_BTF_LOAD command. This allows loading BTF from unprivileged process as long as it has BPF token allowing BPF_BTF_LOAD command, which can be created and delegated by privileged process. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-15-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
37891cea66 |
libbpf: add BPF token support to bpf_map_create() API
Add ability to provide token_fd for BPF_MAP_CREATE command through bpf_map_create() API. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-14-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
ecd435143e |
libbpf: add bpf_token_create() API
Add low-level wrapper API for BPF_TOKEN_CREATE command in bpf() syscall. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-13-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Ian Rogers
|
f8846a1a3c |
tools api fs: Avoid reading whole file for a 1 byte bool
sysfs__read_bool() used the first byte from a fully read file into a string. It then looked at the first byte's value. Avoid doing this and just read the first byte. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Colin Ian King <colin.i.king@gmail.com> Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: German Gomez <german.gomez@arm.com> Cc: Guilherme Amadio <amadio@gentoo.org> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Li Dong <lidong@vivo.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Ming Wang <wangming01@loongson.cn> Cc: Nick Terrell <terrelln@fb.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Vincent Whitchurch <vincent.whitchurch@axis.com> Cc: Wenyu Liu <liuwenyu7@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Link: https://lore.kernel.org/r/20231127220902.1315692-6-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Ian Rogers
|
b6a15269ce |
tools api fs: Switch filename__read_str to use io.h
filename__read_str() has its own string reading code that allocates memory before reading into it. The memory allocated is sized at BUFSIZ that is 8kb. Most strings are short and so most of this 8kb is wasted. Refactor io__getline(), as io__getdelim(), so that the newline character can be configurable and ignored in the case of filename__read_str(). Code like build_caches_for_cpu() in perf's header.c will read many strings and hold them in a data structure, in this case multiple strings per cache level per CPU. Using io.h's io__getline() avoids the wasted memory as strings are temporarily read into a buffer on the stack before being copied to a buffer that grows 128 bytes at a time and is never sized larger than the string. For a 16 hyperthread system the memory consumption of "perf record true" is reduced by 180kb, primarily through saving memory when reading the cache information. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Colin Ian King <colin.i.king@gmail.com> Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: German Gomez <german.gomez@arm.com> Cc: Guilherme Amadio <amadio@gentoo.org> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Li Dong <lidong@vivo.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Ming Wang <wangming01@loongson.cn> Cc: Nick Terrell <terrelln@fb.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Vincent Whitchurch <vincent.whitchurch@axis.com> Cc: Wenyu Liu <liuwenyu7@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Link: https://lore.kernel.org/r/20231127220902.1315692-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Ian Rogers
|
366efbff58 |
libperf: Lazily allocate/size mmap event copy
The event copy in the mmap is used to have storage to read an event. Not
all users of mmaps read the events, such as perf record. The amount of
buffer was also statically set to PERF_SAMPLE_MAX_SIZE rather than the
amount necessary from the header's event size.
Switch to a model where the event_copy is reallocated if too small to
the event's size. This adds the potential for the event to move, so if a
copy of the event pointer were stored it could be broken. All the
current users do:
while(event = perf_mmap__read_event()) { ... }
and so they would be broken due to the event being overwritten if they
had stored the pointer. Manual inspection and address sanitizer testing
also shows the event pointer not being stored.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Guilherme Amadio <amadio@gentoo.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Li Dong <lidong@vivo.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Steinar H. Gunderson <sesse@google.com>
Cc: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: Wenyu Liu <liuwenyu7@huawei.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Link: https://lore.kernel.org/r/20231127220902.1315692-3-irogers@google.com
[ Replace two lines with equivalent zfree(&map->event_copy) ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Arnaldo Carvalho de Melo
|
af76b2dec0 |
libapi: Add missing linux/types.h header to get the __u64 type on io.h
There are functions using __u64, so we need to have the linux/types.h
header otherwise we'll break when its not included before api/io.h.
Fixes:
|
||
Jiri Olsa
|
48f0dfd8d3 |
libbpf: Add st_type argument to elf_resolve_syms_offsets function
We need to get offsets for static variables in following changes, so making elf_resolve_syms_offsets to take st_type value as argument and passing it to elf_sym_iter_new. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/20231125193130.834322-2-jolsa@kernel.org |
||
Eduard Zingerman
|
b8d78cb2e2 |
libbpf: Start v1.4 development cycle
Bump libbpf.map to v1.4.0 to start a new libbpf version cycle. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20231123000439.12025-1-eddyz87@gmail.com |
||
Yonghong Song
|
7f7c43693c |
libbpf: Fix potential uninitialized tail padding with LIBBPF_OPTS_RESET
Martin reported that there is a libbpf complaining of non-zero-value tail
padding with LIBBPF_OPTS_RESET macro if struct bpf_netkit_opts is modified
to have a 4-byte tail padding. This only happens to clang compiler.
The commend line is: ./test_progs -t tc_netkit_multi_links
Martin and I did some investigation and found this indeed the case and
the following are the investigation details.
Clang:
clang version 18.0.0
<I tried clang15/16/17 and they all have similar results>
tools/lib/bpf/libbpf_common.h:
#define LIBBPF_OPTS_RESET(NAME, ...) \
do { \
memset(&NAME, 0, sizeof(NAME)); \
NAME = (typeof(NAME)) { \
.sz = sizeof(NAME), \
__VA_ARGS__ \
}; \
} while (0)
#endif
tools/lib/bpf/libbpf.h:
struct bpf_netkit_opts {
/* size of this struct, for forward/backward compatibility */
size_t sz;
__u32 flags;
__u32 relative_fd;
__u32 relative_id;
__u64 expected_revision;
size_t :0;
};
#define bpf_netkit_opts__last_field expected_revision
In the above struct bpf_netkit_opts, there is no tail padding.
prog_tests/tc_netkit.c:
static void serial_test_tc_netkit_multi_links_target(int mode, int target)
{
...
LIBBPF_OPTS(bpf_netkit_opts, optl);
...
LIBBPF_OPTS_RESET(optl,
.flags = BPF_F_BEFORE,
.relative_fd = bpf_program__fd(skel->progs.tc1),
);
...
}
Let us make the following source change, note that we have a 4-byte
tailing padding now.
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index 6cd9c501624f..0dd83910ae9a 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -803,13 +803,13 @@ bpf_program__attach_tcx(const struct bpf_program *prog, int ifindex,
struct bpf_netkit_opts {
/* size of this struct, for forward/backward compatibility */
size_t sz;
- __u32 flags;
__u32 relative_fd;
__u32 relative_id;
__u64 expected_revision;
+ __u32 flags;
size_t :0;
};
-#define bpf_netkit_opts__last_field expected_revision
+#define bpf_netkit_opts__last_field flags
The clang 18 generated asm code looks like below:
; LIBBPF_OPTS_RESET(optl,
55e3: 48 8d 7d 98 leaq -0x68(%rbp), %rdi
55e7: 31 f6 xorl %esi, %esi
55e9: ba 20 00 00 00 movl $0x20, %edx
55ee: e8 00 00 00 00 callq 0x55f3 <serial_test_tc_netkit_multi_links_target+0x18d3>
55f3: 48 c7 85 10 fd ff ff 20 00 00 00 movq $0x20, -0x2f0(%rbp)
55fe: 48 8b 85 68 ff ff ff movq -0x98(%rbp), %rax
5605: 48 8b 78 18 movq 0x18(%rax), %rdi
5609: e8 00 00 00 00 callq 0x560e <serial_test_tc_netkit_multi_links_target+0x18ee>
560e: 89 85 18 fd ff ff movl %eax, -0x2e8(%rbp)
5614: c7 85 1c fd ff ff 00 00 00 00 movl $0x0, -0x2e4(%rbp)
561e: 48 c7 85 20 fd ff ff 00 00 00 00 movq $0x0, -0x2e0(%rbp)
5629: c7 85 28 fd ff ff 08 00 00 00 movl $0x8, -0x2d8(%rbp)
5633: 48 8b 85 10 fd ff ff movq -0x2f0(%rbp), %rax
563a: 48 89 45 98 movq %rax, -0x68(%rbp)
563e: 48 8b 85 18 fd ff ff movq -0x2e8(%rbp), %rax
5645: 48 89 45 a0 movq %rax, -0x60(%rbp)
5649: 48 8b 85 20 fd ff ff movq -0x2e0(%rbp), %rax
5650: 48 89 45 a8 movq %rax, -0x58(%rbp)
5654: 48 8b 85 28 fd ff ff movq -0x2d8(%rbp), %rax
565b: 48 89 45 b0 movq %rax, -0x50(%rbp)
; link = bpf_program__attach_netkit(skel->progs.tc2, ifindex, &optl);
At -O0 level, the clang compiler creates an intermediate copy.
We have below to store 'flags' with 4-byte store and leave another 4 byte
in the same 8-byte-aligned storage undefined,
5629: c7 85 28 fd ff ff 08 00 00 00 movl $0x8, -0x2d8(%rbp)
and later we store 8-byte to the original zero'ed buffer
5654: 48 8b 85 28 fd ff ff movq -0x2d8(%rbp), %rax
565b: 48 89 45 b0 movq %rax, -0x50(%rbp)
This caused a problem as the 4-byte value at [%rbp-0x2dc, %rbp-0x2e0)
may be garbage.
gcc (gcc 11.4) does not have this issue as it does zeroing struct first before
doing assignments:
; LIBBPF_OPTS_RESET(optl,
50fd: 48 8d 85 40 fc ff ff leaq -0x3c0(%rbp), %rax
5104: ba 20 00 00 00 movl $0x20, %edx
5109: be 00 00 00 00 movl $0x0, %esi
510e: 48 89 c7 movq %rax, %rdi
5111: e8 00 00 00 00 callq 0x5116 <serial_test_tc_netkit_multi_links_target+0x1522>
5116: 48 8b 45 f0 movq -0x10(%rbp), %rax
511a: 48 8b 40 18 movq 0x18(%rax), %rax
511e: 48 89 c7 movq %rax, %rdi
5121: e8 00 00 00 00 callq 0x5126 <serial_test_tc_netkit_multi_links_target+0x1532>
5126: 48 c7 85 40 fc ff ff 00 00 00 00 movq $0x0, -0x3c0(%rbp)
5131: 48 c7 85 48 fc ff ff 00 00 00 00 movq $0x0, -0x3b8(%rbp)
513c: 48 c7 85 50 fc ff ff 00 00 00 00 movq $0x0, -0x3b0(%rbp)
5147: 48 c7 85 58 fc ff ff 00 00 00 00 movq $0x0, -0x3a8(%rbp)
5152: 48 c7 85 40 fc ff ff 20 00 00 00 movq $0x20, -0x3c0(%rbp)
515d: 89 85 48 fc ff ff movl %eax, -0x3b8(%rbp)
5163: c7 85 58 fc ff ff 08 00 00 00 movl $0x8, -0x3a8(%rbp)
; link = bpf_program__attach_netkit(skel->progs.tc2, ifindex, &optl);
It is not clear how to resolve the compiler code generation as the compiler
generates correct code w.r.t. how to handle unnamed padding in C standard.
So this patch changed LIBBPF_OPTS_RESET macro to avoid uninitialized tail
padding. We already knows LIBBPF_OPTS macro works on both gcc and clang,
even with tail padding. So LIBBPF_OPTS_RESET is changed to be a
LIBBPF_OPTS followed by a memcpy(), thus avoiding uninitialized tail padding.
The below is asm code generated with this patch and with clang compiler:
; LIBBPF_OPTS_RESET(optl,
55e3: 48 8d bd 10 fd ff ff leaq -0x2f0(%rbp), %rdi
55ea: 31 f6 xorl %esi, %esi
55ec: ba 20 00 00 00 movl $0x20, %edx
55f1: e8 00 00 00 00 callq 0x55f6 <serial_test_tc_netkit_multi_links_target+0x18d6>
55f6: 48 c7 85 10 fd ff ff 20 00 00 00 movq $0x20, -0x2f0(%rbp)
5601: 48 8b 85 68 ff ff ff movq -0x98(%rbp), %rax
5608: 48 8b 78 18 movq 0x18(%rax), %rdi
560c: e8 00 00 00 00 callq 0x5611 <serial_test_tc_netkit_multi_links_target+0x18f1>
5611: 89 85 18 fd ff ff movl %eax, -0x2e8(%rbp)
5617: c7 85 1c fd ff ff 00 00 00 00 movl $0x0, -0x2e4(%rbp)
5621: 48 c7 85 20 fd ff ff 00 00 00 00 movq $0x0, -0x2e0(%rbp)
562c: c7 85 28 fd ff ff 08 00 00 00 movl $0x8, -0x2d8(%rbp)
5636: 48 8b 85 10 fd ff ff movq -0x2f0(%rbp), %rax
563d: 48 89 45 98 movq %rax, -0x68(%rbp)
5641: 48 8b 85 18 fd ff ff movq -0x2e8(%rbp), %rax
5648: 48 89 45 a0 movq %rax, -0x60(%rbp)
564c: 48 8b 85 20 fd ff ff movq -0x2e0(%rbp), %rax
5653: 48 89 45 a8 movq %rax, -0x58(%rbp)
5657: 48 8b 85 28 fd ff ff movq -0x2d8(%rbp), %rax
565e: 48 89 45 b0 movq %rax, -0x50(%rbp)
; link = bpf_program__attach_netkit(skel->progs.tc2, ifindex, &optl);
In the above code, a temporary buffer is zeroed and then has proper value assigned.
Finally, values in temporary buffer are copied to the original variable buffer,
hence tail padding is guaranteed to be 0.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/bpf/20231107201511.2548645-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
||
|
Linus Torvalds
|
7ab89417ed |
perf tools changes for v6.7
Build
-----
* Compile BPF programs by default if clang (>= 12.0.1) is available to
enable more features like kernel lock contention, off-cpu profiling,
kwork, sample filtering and so on. It can be disabled by passing
BUILD_BPF_SKEL=0 to make.
* Produce better error messages for bison on debug build (make DEBUG=1)
by defining YYDEBUG symbol internally.
perf record
-----------
* Track sideband events (like FORK/MMAP) from all CPUs even if perf record
targets a subset of CPUs only (using -C option). Otherwise it may lose
some information happened on a CPU out of the target list.
* Fix checking raw sched_switch tracepoint argument using system BTF.
This affects off-cpu profiling which attaches a BPF program to the raw
tracepoint.
perf lock contention
--------------------
* Add --lock-cgroup option to see contention by cgroups. This should be
used with BPF only (using -b option).
$ sudo perf lock con -ab --lock-cgroup -- sleep 1
contended total wait max wait avg wait cgroup
835 14.06 ms 41.19 us 16.83 us /system.slice/led.service
25 122.38 us 13.77 us 4.89 us /
44 23.73 us 3.87 us 539 ns /user.slice/user-657345.slice/session-c4.scope
1 491 ns 491 ns 491 ns /system.slice/connectd.service
* Add -G/--cgroup-filter option to see contention only for given cgroups.
This can be useful when you identified a cgroup in the above command and
want to investigate more on it. It also works with other output options
like -t/--threads and -l/--lock-addr.
$ sudo perf lock con -ab -G /user.slice/user-657345.slice/session-c4.scope -- sleep 1
contended total wait max wait avg wait type caller
8 77.11 us 17.98 us 9.64 us spinlock futex_wake+0xc8
2 24.56 us 14.66 us 12.28 us spinlock tick_do_update_jiffies64+0x25
1 4.97 us 4.97 us 4.97 us spinlock futex_q_lock+0x2a
* Use per-cpu array for better spinlock tracking. This is to improve
performance of the BPF program and to avoid nested contention on a lock
in the BPF hash map.
* Update callstack check for PowerPC. To find a representative caller of a
lock, it needs to look up the call stacks. It ends the lookup when it sees
0 in the call stack buffer. However, PowerPC call stacks can have 0 values
in the beginning so skip them when it expects valid call stacks after.
perf kwork
----------
* Support 'sched' class (for -k option) so that it can see task scheduling
event (using sched_switch tracepoint) as well as irq and workqueue items.
* Add perf kwork top subcommand to show more accurate cpu utilization with
sched class above. It works both with a recorded data (using perf kwork
record command) and BPF (using -b option). Unlike perf top command, it
does not support interactive mode (yet).
$ sudo perf kwork top -b -k sched
Starting trace, Hit <Ctrl+C> to stop and report
^C
Total : 160702.425 ms, 8 cpus
%Cpu(s): 36.00% id, 0.00% hi, 0.00% si
%Cpu0 [|||||||||||||||||| 61.66%]
%Cpu1 [|||||||||||||||||| 61.27%]
%Cpu2 [||||||||||||||||||| 66.40%]
%Cpu3 [|||||||||||||||||| 61.28%]
%Cpu4 [|||||||||||||||||| 61.82%]
%Cpu5 [||||||||||||||||||||||| 77.41%]
%Cpu6 [|||||||||||||||||| 61.73%]
%Cpu7 [|||||||||||||||||| 63.25%]
PID SPID %CPU RUNTIME COMMMAND
-------------------------------------------------------------
0 0 38.72 8089.463 ms [swapper/1]
0 0 38.71 8084.547 ms [swapper/3]
0 0 38.33 8007.532 ms [swapper/0]
0 0 38.26 7992.985 ms [swapper/6]
0 0 38.17 7971.865 ms [swapper/4]
0 0 36.74 7447.765 ms [swapper/7]
0 0 33.59 6486.942 ms [swapper/2]
0 0 22.58 3771.268 ms [swapper/5]
9545 9351 2.48 447.136 ms sched-messaging
9574 9351 2.09 418.583 ms sched-messaging
9724 9351 2.05 372.407 ms sched-messaging
9531 9351 2.01 368.804 ms sched-messaging
9512 9351 2.00 362.250 ms sched-messaging
9514 9351 1.95 357.767 ms sched-messaging
9538 9351 1.86 384.476 ms sched-messaging
9712 9351 1.84 386.490 ms sched-messaging
9723 9351 1.83 380.021 ms sched-messaging
9722 9351 1.82 382.738 ms sched-messaging
9517 9351 1.81 354.794 ms sched-messaging
9559 9351 1.79 344.305 ms sched-messaging
9725 9351 1.77 365.315 ms sched-messaging
<SNIP>
* Add hard/soft-irq statistics to perf kwork top. This will show the
total CPU utilization with IRQ stats like below:
$ sudo perf kwork top -b -k sched,irq,softirq
Starting trace, Hit <Ctrl+C> to stop and report
^C
Total : 12554.889 ms, 8 cpus
%Cpu(s): 96.23% id, 0.10% hi, 0.19% si <---- here
%Cpu0 [| 4.60%]
%Cpu1 [| 4.59%]
%Cpu2 [ 2.73%]
%Cpu3 [| 3.81%]
<SNIP>
perf bench
----------
* Add -G/--cgroups option to perf bench sched pipe. The pipe bench is
good to measure context switch overhead. With this option, it puts
the reader and writer tasks in separate cgroups to enforce context
switch between two different cgroups.
Also it needs to set CPU affinity of the tasks in a CPU to accurately
measure the impact of cgroup context switches.
$ sudo perf stat -e context-switches,cgroup-switches -- \
> taskset -c 0 perf bench sched pipe -l 100000
# Running 'sched/pipe' benchmark:
# Executed 100000 pipe operations between two processes
Total time: 0.307 [sec]
3.078180 usecs/op
324867 ops/sec
Performance counter stats for 'taskset -c 0 perf bench sched pipe -l 100000':
200,026 context-switches
63 cgroup-switches
0.321637922 seconds time elapsed
You can see small number of cgroup-switches because both write and read
tasks are in the same cgroup.
$ sudo mkdir /sys/fs/cgroup/{AAA,BBB}
$ sudo perf stat -e context-switches,cgroup-switches -- \
> taskset -c 0 perf bench sched pipe -l 100000 -G AAA,BBB
# Running 'sched/pipe' benchmark:
# Executed 100000 pipe operations between two processes
Total time: 0.351 [sec]
3.512990 usecs/op
284657 ops/sec
Performance counter stats for 'taskset -c 0 perf bench sched pipe -l 100000 -G AAA,BBB':
200,020 context-switches
200,019 cgroup-switches
0.365034567 seconds time elapsed
Now context-switches and cgroup-switches are almost same. And you can
see the pipe operation took little more.
* Kill child processes when perf bench sched messaging exited abnormally.
Otherwise it'd leave the child doing unnecessary work.
perf test
---------
* Fix various shellcheck issues on the tests written in shell script.
* Skip tests when condition is not satisfied:
- object code reading test for non-text section addresses.
- CoreSight test if cs_etm// event is not available.
- lock contention test if not enough CPUs.
Event parsing
-------------
* Make PMU alias name loading lazy to reduce the startup time in the
event parsing code for perf record, stat and others in the general
case.
* Lazily compute PMU default config. In the same sense, delay PMU
initialization until it's really needed to reduce the startup cost.
* Fix event term values that are raw events. The event specification
can have several terms including event name. But sometimes it clashes
with raw event encoding which starts with 'r' and has hex-digits.
For example, an event named 'read' should be processed as a normal
event but it was mis-treated as a raw encoding and caused a failure.
$ perf stat -e 'uncore_imc_free_running/event=read/' -a sleep 1
event syntax error: '..nning/event=read/'
\___ parser error
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
Event metrics
-------------
* Add "Compat" regex to match event with multiple identifiers.
* Usual updates for Intel, Power10, Arm telemetry/CMN and AmpereOne.
Misc
----
* Assorted memory leak fixes and footprint reduction.
* Add "bpf_skeletons" to perf version --build-options so that users can
check whether their perf tools have BPF support easily.
* Fix unaligned access in Intel-PT packet decoder found by undefined-behavior
sanitizer.
* Avoid frequency mode for the dummy event. Surprisingly it'd impact
kernel timer tick handler performance by force iterating all PMU events.
* Update bash shell completion for events and metrics.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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Merge tag 'perf-tools-for-v6.7-1-2023-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools
Pull perf tools updates from Namhyung Kim:
"Build:
- Compile BPF programs by default if clang (>= 12.0.1) is available
to enable more features like kernel lock contention, off-cpu
profiling, kwork, sample filtering and so on.
This can be disabled by passing BUILD_BPF_SKEL=0 to make.
- Produce better error messages for bison on debug build (make
DEBUG=1) by defining YYDEBUG symbol internally.
perf record:
- Track sideband events (like FORK/MMAP) from all CPUs even if perf
record targets a subset of CPUs only (using -C option). Otherwise
it may lose some information happened on a CPU out of the target
list.
- Fix checking raw sched_switch tracepoint argument using system BTF.
This affects off-cpu profiling which attaches a BPF program to the
raw tracepoint.
perf lock contention:
- Add --lock-cgroup option to see contention by cgroups. This should
be used with BPF only (using -b option).
$ sudo perf lock con -ab --lock-cgroup -- sleep 1
contended total wait max wait avg wait cgroup
835 14.06 ms 41.19 us 16.83 us /system.slice/led.service
25 122.38 us 13.77 us 4.89 us /
44 23.73 us 3.87 us 539 ns /user.slice/user-657345.slice/session-c4.scope
1 491 ns 491 ns 491 ns /system.slice/connectd.service
- Add -G/--cgroup-filter option to see contention only for given
cgroups.
This can be useful when you identified a cgroup in the above
command and want to investigate more on it. It also works with
other output options like -t/--threads and -l/--lock-addr.
$ sudo perf lock con -ab -G /user.slice/user-657345.slice/session-c4.scope -- sleep 1
contended total wait max wait avg wait type caller
8 77.11 us 17.98 us 9.64 us spinlock futex_wake+0xc8
2 24.56 us 14.66 us 12.28 us spinlock tick_do_update_jiffies64+0x25
1 4.97 us 4.97 us 4.97 us spinlock futex_q_lock+0x2a
- Use per-cpu array for better spinlock tracking. This is to improve
performance of the BPF program and to avoid nested contention on a
lock in the BPF hash map.
- Update callstack check for PowerPC. To find a representative caller
of a lock, it needs to look up the call stacks. It ends the lookup
when it sees 0 in the call stack buffer. However, PowerPC call
stacks can have 0 values in the beginning so skip them when it
expects valid call stacks after.
perf kwork:
- Support 'sched' class (for -k option) so that it can see task
scheduling event (using sched_switch tracepoint) as well as irq and
workqueue items.
- Add perf kwork top subcommand to show more accurate cpu utilization
with sched class above. It works both with a recorded data (using
perf kwork record command) and BPF (using -b option). Unlike perf
top command, it does not support interactive mode (yet).
$ sudo perf kwork top -b -k sched
Starting trace, Hit <Ctrl+C> to stop and report
^C
Total : 160702.425 ms, 8 cpus
%Cpu(s): 36.00% id, 0.00% hi, 0.00% si
%Cpu0 [|||||||||||||||||| 61.66%]
%Cpu1 [|||||||||||||||||| 61.27%]
%Cpu2 [||||||||||||||||||| 66.40%]
%Cpu3 [|||||||||||||||||| 61.28%]
%Cpu4 [|||||||||||||||||| 61.82%]
%Cpu5 [||||||||||||||||||||||| 77.41%]
%Cpu6 [|||||||||||||||||| 61.73%]
%Cpu7 [|||||||||||||||||| 63.25%]
PID SPID %CPU RUNTIME COMMMAND
-------------------------------------------------------------
0 0 38.72 8089.463 ms [swapper/1]
0 0 38.71 8084.547 ms [swapper/3]
0 0 38.33 8007.532 ms [swapper/0]
0 0 38.26 7992.985 ms [swapper/6]
0 0 38.17 7971.865 ms [swapper/4]
0 0 36.74 7447.765 ms [swapper/7]
0 0 33.59 6486.942 ms [swapper/2]
0 0 22.58 3771.268 ms [swapper/5]
9545 9351 2.48 447.136 ms sched-messaging
9574 9351 2.09 418.583 ms sched-messaging
9724 9351 2.05 372.407 ms sched-messaging
9531 9351 2.01 368.804 ms sched-messaging
9512 9351 2.00 362.250 ms sched-messaging
9514 9351 1.95 357.767 ms sched-messaging
9538 9351 1.86 384.476 ms sched-messaging
9712 9351 1.84 386.490 ms sched-messaging
9723 9351 1.83 380.021 ms sched-messaging
9722 9351 1.82 382.738 ms sched-messaging
9517 9351 1.81 354.794 ms sched-messaging
9559 9351 1.79 344.305 ms sched-messaging
9725 9351 1.77 365.315 ms sched-messaging
<SNIP>
- Add hard/soft-irq statistics to perf kwork top. This will show the
total CPU utilization with IRQ stats like below:
$ sudo perf kwork top -b -k sched,irq,softirq
Starting trace, Hit <Ctrl+C> to stop and report
^C
Total : 12554.889 ms, 8 cpus
%Cpu(s): 96.23% id, 0.10% hi, 0.19% si <---- here
%Cpu0 [| 4.60%]
%Cpu1 [| 4.59%]
%Cpu2 [ 2.73%]
%Cpu3 [| 3.81%]
<SNIP>
perf bench:
- Add -G/--cgroups option to perf bench sched pipe. The pipe bench is
good to measure context switch overhead. With this option, it puts
the reader and writer tasks in separate cgroups to enforce context
switch between two different cgroups.
Also it needs to set CPU affinity of the tasks in a CPU to
accurately measure the impact of cgroup context switches.
$ sudo perf stat -e context-switches,cgroup-switches -- \
> taskset -c 0 perf bench sched pipe -l 100000
# Running 'sched/pipe' benchmark:
# Executed 100000 pipe operations between two processes
Total time: 0.307 [sec]
3.078180 usecs/op
324867 ops/sec
Performance counter stats for 'taskset -c 0 perf bench sched pipe -l 100000':
200,026 context-switches
63 cgroup-switches
0.321637922 seconds time elapsed
You can see small number of cgroup-switches because both write and
read tasks are in the same cgroup.
$ sudo mkdir /sys/fs/cgroup/{AAA,BBB}
$ sudo perf stat -e context-switches,cgroup-switches -- \
> taskset -c 0 perf bench sched pipe -l 100000 -G AAA,BBB
# Running 'sched/pipe' benchmark:
# Executed 100000 pipe operations between two processes
Total time: 0.351 [sec]
3.512990 usecs/op
284657 ops/sec
Performance counter stats for 'taskset -c 0 perf bench sched pipe -l 100000 -G AAA,BBB':
200,020 context-switches
200,019 cgroup-switches
0.365034567 seconds time elapsed
Now context-switches and cgroup-switches are almost same. And you
can see the pipe operation took little more.
- Kill child processes when perf bench sched messaging exited
abnormally. Otherwise it'd leave the child doing unnecessary work.
perf test:
- Fix various shellcheck issues on the tests written in shell script.
- Skip tests when condition is not satisfied:
- object code reading test for non-text section addresses.
- CoreSight test if cs_etm// event is not available.
- lock contention test if not enough CPUs.
Event parsing:
- Make PMU alias name loading lazy to reduce the startup time in the
event parsing code for perf record, stat and others in the general
case.
- Lazily compute PMU default config. In the same sense, delay PMU
initialization until it's really needed to reduce the startup cost.
- Fix event term values that are raw events. The event specification
can have several terms including event name. But sometimes it
clashes with raw event encoding which starts with 'r' and has
hex-digits.
For example, an event named 'read' should be processed as a normal
event but it was mis-treated as a raw encoding and caused a
failure.
$ perf stat -e 'uncore_imc_free_running/event=read/' -a sleep 1
event syntax error: '..nning/event=read/'
\___ parser error
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
Event metrics:
- Add "Compat" regex to match event with multiple identifiers.
- Usual updates for Intel, Power10, Arm telemetry/CMN and AmpereOne.
Misc:
- Assorted memory leak fixes and footprint reduction.
- Add "bpf_skeletons" to perf version --build-options so that users
can check whether their perf tools have BPF support easily.
- Fix unaligned access in Intel-PT packet decoder found by
undefined-behavior sanitizer.
- Avoid frequency mode for the dummy event. Surprisingly it'd impact
kernel timer tick handler performance by force iterating all PMU
events.
- Update bash shell completion for events and metrics"
* tag 'perf-tools-for-v6.7-1-2023-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (187 commits)
perf vendor events intel: Update tsx_cycles_per_elision metrics
perf vendor events intel: Update bonnell version number to v5
perf vendor events intel: Update westmereex events to v4
perf vendor events intel: Update meteorlake events to v1.06
perf vendor events intel: Update knightslanding events to v16
perf vendor events intel: Add typo fix for ivybridge FP
perf vendor events intel: Update a spelling in haswell/haswellx
perf vendor events intel: Update emeraldrapids to v1.01
perf vendor events intel: Update alderlake/alderlake events to v1.23
perf build: Disable BPF skeletons if clang version is < 12.0.1
perf callchain: Fix spelling mistake "statisitcs" -> "statistics"
perf report: Fix spelling mistake "heirachy" -> "hierarchy"
perf python: Fix binding linkage due to rename and move of evsel__increase_rlimit()
perf tests: test_arm_coresight: Simplify source iteration
perf vendor events intel: Add tigerlake two metrics
perf vendor events intel: Add broadwellde two metrics
perf vendor events intel: Fix broadwellde tma_info_system_dram_bw_use metric
perf mem_info: Add and use map_symbol__exit and addr_map_symbol__exit
perf callchain: Minor layout changes to callchain_list
perf callchain: Make brtype_stat in callchain_list optional
...
|
||
|
Ian Rogers
|
78c32f4cb1 |
libperf rc_check: Add RC_CHK_EQUAL
Comparing pointers with reference count checking is tricky to avoid a SEGV. Add a convenience macro to simplify and use. Signed-off-by: Ian Rogers <irogers@google.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: German Gomez <german.gomez@arm.com> Cc: James Clark <james.clark@arm.com> Cc: Nick Terrell <terrelln@fb.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: liuwenyu <liuwenyu7@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Song Liu <song@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Link: https://lore.kernel.org/r/20231024222353.3024098-5-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> |
||
|
Ian Rogers
|
75265320d2 |
libperf rc_check: Make implicit enabling work for GCC
Make the implicit REFCOUNT_CHECKING robust to when building with GCC.
Fixes:
|
||
Daniel Borkmann
|
05c31b4ab2 |
libbpf: Add link-based API for netkit
This adds bpf_program__attach_netkit() API to libbpf. Overall it is very
similar to tcx. The API looks as following:
LIBBPF_API struct bpf_link *
bpf_program__attach_netkit(const struct bpf_program *prog, int ifindex,
const struct bpf_netkit_opts *opts);
The struct bpf_netkit_opts is done in similar way as struct bpf_tcx_opts
for supporting bpf_mprog control parameters. The attach location for the
primary and peer device is derived from the program section "netkit/primary"
and "netkit/peer", respectively.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20231024214904.29825-4-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
|
||
|
Andrii Nakryiko
|
137df1189d |
libbpf: Don't assume SHT_GNU_verdef presence for SHT_GNU_versym section
Fix too eager assumption that SHT_GNU_verdef ELF section is going to be
present whenever binary has SHT_GNU_versym section. It seems like either
SHT_GNU_verdef or SHT_GNU_verneed can be used, so failing on missing
SHT_GNU_verdef actually breaks use cases in production.
One specific reported issue, which was used to manually test this fix,
was trying to attach to `readline` function in BASH binary.
Fixes:
|
||
|
Ian Rogers
|
c4b5140c6e |
tools api: Avoid potential double free
io__getline will free the line on error but it doesn't clear the out argument. This may lead to the line being freed twice, like in tools/perf/util/srcline.c as detected by clang-tidy. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: llvm@lists.linux.dev Cc: Ming Wang <wangming01@loongson.cn> Cc: Tom Rix <trix@redhat.com> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20231009183920.200859-17-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> |
||
Daan De Meyer
|
bf90438c78 |
libbpf: Add support for cgroup unix socket address hooks
Add the necessary plumbing to hook up the new cgroup unix sockaddr hooks into libbpf. Signed-off-by: Daan De Meyer <daan.j.demeyer@gmail.com> Link: https://lore.kernel.org/r/20231011185113.140426-6-daan.j.demeyer@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
||
Alexandre Ghiti
|
8a412c5c1c |
libbpf: Fix syscall access arguments on riscv
Since commit |
||
Hengqi Chen
|
2147c8d07e |
libbpf: Allow Golang symbols in uprobe secdef
Golang symbols in ELF files are different from C/C++
which contains special characters like '*', '(' and ')'.
With generics, things get more complicated, there are
symbols like:
github.com/cilium/ebpf/internal.(*Deque[go.shape.interface { Format(fmt.State, int32); TypeName() string;github.com/cilium/ebpf/btf.copy() github.com/cilium/ebpf/btf.Type}]).Grow
Matching such symbols using `%m[^\n]` in sscanf, this
excludes newline which typically does not appear in ELF
symbols. This should work in most use-cases and also
work for unicode letters in identifiers. If newline do
show up in ELF symbols, users can still attach to such
symbol by specifying bpf_uprobe_opts::func_name.
A working example can be found at this repo ([0]).
[0]: https://github.com/chenhengqi/libbpf-go-symbols
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20230929155954.92448-1-hengqi.chen@gmail.com
|
||
Martin Kelly
|
16058ff28b |
libbpf: Add ring__consume
Add ring__consume to consume a single ringbuffer, analogous to ring_buffer__consume. Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230925215045.2375758-14-martin.kelly@crowdstrike.com |
||
|
Martin Kelly
|
ae76939037 |
libbpf: Add ring__map_fd
Add ring__map_fd to get the file descriptor underlying a given ringbuffer. Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230925215045.2375758-12-martin.kelly@crowdstrike.com |
||
|
Martin Kelly
|
e79abf717f |
libbpf: Add ring__size
Add ring__size to get the total size of a given ringbuffer. Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230925215045.2375758-10-martin.kelly@crowdstrike.com |
||
|
Martin Kelly
|
3b34d29726 |
libbpf: Add ring__avail_data_size
Add ring__avail_data_size for querying the currently available data in the ringbuffer, similar to the BPF_RB_AVAIL_DATA flag in bpf_ringbuf_query. This is racy during ongoing operations but is still useful for overall information on how a ringbuffer is behaving. Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230925215045.2375758-8-martin.kelly@crowdstrike.com |
||
|
Martin Kelly
|
059a8c0c5a |
libbpf: Add ring__producer_pos, ring__consumer_pos
Add APIs to get the producer and consumer position for a given ringbuffer. Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230925215045.2375758-6-martin.kelly@crowdstrike.com |
||
|
Martin Kelly
|
1c97f6afd7 |
libbpf: Add ring_buffer__ring
Add a new function ring_buffer__ring, which exposes struct ring * to the user, representing a single ringbuffer. Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230925215045.2375758-4-martin.kelly@crowdstrike.com |
||
|
Martin Kelly
|
ef3b82003e |
libbpf: Switch rings to array of pointers
Switch rb->rings to be an array of pointers instead of a contiguous block. This allows for each ring pointer to be stable after ring_buffer__add is called, which allows us to expose struct ring * to the user without gotchas. Without this change, the realloc in ring_buffer__add could invalidate a struct ring *, making it unsafe to give to the user. Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230925215045.2375758-3-martin.kelly@crowdstrike.com |
||
|
Martin Kelly
|
4448f64c54 |
libbpf: Refactor cleanup in ring_buffer__add
Refactor the cleanup code in ring_buffer__add to use a unified err_out label. This reduces code duplication, as well as plugging a potential leak if mmap_sz != (__u64)(size_t)mmap_sz (currently this would miss unmapping tmp because ringbuf_unmap_ring isn't called). Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230925215045.2375758-2-martin.kelly@crowdstrike.com |
||
|
Hengqi Chen
|
bb7fa09399 |
libbpf: Support symbol versioning for uprobe
In current implementation, we assume that symbol found in .dynsym section
would have a version suffix and use it to compare with symbol user supplied.
According to the spec ([0]), this assumption is incorrect, the version info
of dynamic symbols are stored in .gnu.version and .gnu.version_d sections
of ELF objects. For example:
$ nm -D /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
000000000009b1a0 T __pthread_rwlock_wrlock@GLIBC_2.2.5
000000000009b1a0 T pthread_rwlock_wrlock@@GLIBC_2.34
000000000009b1a0 T pthread_rwlock_wrlock@GLIBC_2.2.5
$ readelf -W --dyn-syms /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
706: 000000000009b1a0 878 FUNC GLOBAL DEFAULT 15 __pthread_rwlock_wrlock@GLIBC_2.2.5
2568: 000000000009b1a0 878 FUNC GLOBAL DEFAULT 15 pthread_rwlock_wrlock@@GLIBC_2.34
2571: 000000000009b1a0 878 FUNC GLOBAL DEFAULT 15 pthread_rwlock_wrlock@GLIBC_2.2.5
In this case, specify pthread_rwlock_wrlock@@GLIBC_2.34 or
pthread_rwlock_wrlock@GLIBC_2.2.5 in bpf_uprobe_opts::func_name won't work.
Because the qualified name does NOT match `pthread_rwlock_wrlock` (without
version suffix) in .dynsym sections.
This commit implements the symbol versioning for dynsym and allows user to
specify symbol in the following forms:
- func
- func@LIB_VERSION
- func@@LIB_VERSION
In case of symbol conflicts, error out and users should resolve it by
specifying a qualified name.
[0]: https://refspecs.linuxfoundation.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/symversion.html
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230918024813.237475-3-hengqi.chen@gmail.com
|
||
|
Hengqi Chen
|
7257cee652 |
libbpf: Resolve symbol conflicts at the same offset for uprobe
Dynamic symbols in shared library may have the same name, for example:
$ nm -D /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
000000000009b1a0 T __pthread_rwlock_wrlock@GLIBC_2.2.5
000000000009b1a0 T pthread_rwlock_wrlock@@GLIBC_2.34
000000000009b1a0 T pthread_rwlock_wrlock@GLIBC_2.2.5
$ readelf -W --dyn-syms /lib/x86_64-linux-gnu/libc.so.6 | grep rwlock_wrlock
706: 000000000009b1a0 878 FUNC GLOBAL DEFAULT 15 __pthread_rwlock_wrlock@GLIBC_2.2.5
2568: 000000000009b1a0 878 FUNC GLOBAL DEFAULT 15 pthread_rwlock_wrlock@@GLIBC_2.34
2571: 000000000009b1a0 878 FUNC GLOBAL DEFAULT 15 pthread_rwlock_wrlock@GLIBC_2.2.5
Currently, users can't attach a uprobe to pthread_rwlock_wrlock because
there are two symbols named pthread_rwlock_wrlock and both are global
bind. And libbpf considers it as a conflict.
Since both of them are at the same offset we could accept one of them
harmlessly. Note that we already does this in elf_resolve_syms_offsets.
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230918024813.237475-2-hengqi.chen@gmail.com
|
||
David S. Miller
|
685c6d5b2c |
Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says: ==================== The following pull-request contains BPF updates for your *net-next* tree. We've added 73 non-merge commits during the last 9 day(s) which contain a total of 79 files changed, 5275 insertions(+), 600 deletions(-). The main changes are: 1) Basic BTF validation in libbpf, from Andrii Nakryiko. 2) bpf_assert(), bpf_throw(), exceptions in bpf progs, from Kumar Kartikeya Dwivedi. 3) next_thread cleanups, from Oleg Nesterov. 4) Add mcpu=v4 support to arm32, from Puranjay Mohan. 5) Add support for __percpu pointers in bpf progs, from Yonghong Song. 6) Fix bpf tailcall interaction with bpf trampoline, from Leon Hwang. 7) Raise irq_work in bpf_mem_alloc while irqs are disabled to improve refill probabablity, from Hou Tao. Please consider pulling these changes from: git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git Thanks a lot! Also thanks to reporters, reviewers and testers of commits in this pull-request: Alan Maguire, Andrey Konovalov, Dave Marchevsky, "Eric W. Biederman", Jiri Olsa, Maciej Fijalkowski, Quentin Monnet, Russell King (Oracle), Song Liu, Stanislav Fomichev, Yonghong Song ==================== Signed-off-by: David S. Miller <davem@davemloft.net> |
||
Kumar Kartikeya Dwivedi
|
7e2925f672 |
libbpf: Add support for custom exception callbacks
Add support to libbpf to append exception callbacks when loading a program. The exception callback is found by discovering the declaration tag 'exception_callback:<value>' and finding the callback in the value of the tag. The process is done in two steps. First, for each main program, the bpf_object__sanitize_and_load_btf function finds and marks its corresponding exception callback as defined by the declaration tag on it. Second, bpf_object__reloc_code is modified to append the indicated exception callback at the end of the instruction iteration (since exception callback will never be appended in that loop, as it is not directly referenced). Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20230912233214.1518551-16-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Kumar Kartikeya Dwivedi
|
6c918709bd |
libbpf: Refactor bpf_object__reloc_code
Refactor bpf_object__append_subprog_code out of bpf_object__reloc_code to be able to reuse it to append subprog related code for the exception callback to the main program. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20230912233214.1518551-15-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
Yang Jihong
|
f6ff1c7604 |
perf evlist: Add perf_evlist__go_system_wide() helper
For dummy events that keep tracking, we may need to modify its cpu_maps. For example, change the cpu_maps to record sideband events for all CPUS. Add perf_evlist__go_system_wide() helper to support this scenario. Signed-off-by: Yang Jihong <yangjihong1@huawei.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Tested-by: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Richter <tmricht@linux.ibm.com> Link: https://lore.kernel.org/r/20230904023340.12707-2-yangjihong1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Linus Torvalds
|
535a265d7f |
perf tools changes for v6.6:
perf tools maintainership:
- Add git information for perf-tools and perf-tools-next trees/branches to the
MAINTAINERS file. That is where development now takes place and myself and
Namhyung Kim have write access, more people to come as we emulate other
maintainer groups.
perf record:
- Record kernel data maps when 'perf record --data' is used, so that global variables can
be resolved and used in tools that do data profiling.
perf trace:
- Remove the old, experimental support for BPF events in which a .c file was passed as
an event: "perf trace -e hello.c" to then get compiled and loaded.
The only known usage for that, that shipped with the kernel as an example for such events,
augmented the raw_syscalls tracepoints and was converted to a libbpf skeleton, reusing all
the user space components and the BPF code connected to the syscalls.
In the end just the way to glue the BPF part and the user space type beautifiers changed,
now being performed by libbpf skeletons.
The next step is to use BTF to do pretty printing of all syscall types, as discussed with
Alan Maguire and others.
Now, on a perf built with BUILD_BPF_SKEL=1 we get most if not all path/filenames/strings,
some of the networking data structures, perf_event_attr, etc, i.e. systemwide tracing of
nanosleep calls and perf_event_open syscalls while 'perf stat' runs 'sleep' for 5 seconds:
# perf trace -a -e *nanosleep,perf* perf stat -e cycles,instructions sleep 5
0.000 ( 9.034 ms): perf/327641 perf_event_open(attr_uptr: { type: 0 (PERF_TYPE_HARDWARE), size: 136, config: 0 (PERF_COUNT_HW_CPU_CYCLES), sample_type: IDENTIFIER, read_format: TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING, disabled: 1, inherit: 1, enable_on_exec: 1, exclude_guest: 1 }, pid: 327642 (perf), cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
9.039 ( 0.006 ms): perf/327641 perf_event_open(attr_uptr: { type: 0 (PERF_TYPE_HARDWARE), size: 136, config: 0x1 (PERF_COUNT_HW_INSTRUCTIONS), sample_type: IDENTIFIER, read_format: TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING, disabled: 1, inherit: 1, enable_on_exec: 1, exclude_guest: 1 }, pid: 327642 (perf-exec), cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
? ( ): gpm/991 ... [continued]: clock_nanosleep()) = 0
10.133 ( ): sleep/327642 clock_nanosleep(rqtp: { .tv_sec: 5, .tv_nsec: 0 }, rmtp: 0x7ffd36f83ed0) ...
? ( ): pool-gsd-smart/3051 ... [continued]: clock_nanosleep()) = 0
30.276 ( ): gpm/991 clock_nanosleep(rqtp: { .tv_sec: 2, .tv_nsec: 0 }, rmtp: 0x7ffcc6f73710) ...
223.215 (1000.430 ms): pool-gsd-smart/3051 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 0 }, rmtp: 0x7f6e7fffec90) = 0
30.276 (2000.394 ms): gpm/991 ... [continued]: clock_nanosleep()) = 0
1230.814 ( ): pool-gsd-smart/3051 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 0 }, rmtp: 0x7f6e7fffec90) ...
1230.814 (1000.404 ms): pool-gsd-smart/3051 ... [continued]: clock_nanosleep()) = 0
2030.886 ( ): gpm/991 clock_nanosleep(rqtp: { .tv_sec: 2, .tv_nsec: 0 }, rmtp: 0x7ffcc6f73710) ...
2237.709 (1000.153 ms): pool-gsd-smart/3051 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 0 }, rmtp: 0x7f6e7fffec90) = 0
? ( ): crond/1172 ... [continued]: clock_nanosleep()) = 0
3242.699 ( ): pool-gsd-smart/3051 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 0 }, rmtp: 0x7f6e7fffec90) ...
2030.886 (2000.385 ms): gpm/991 ... [continued]: clock_nanosleep()) = 0
3728.078 ( ): crond/1172 clock_nanosleep(rqtp: { .tv_sec: 60, .tv_nsec: 0 }, rmtp: 0x7ffe0971dcf0) ...
3242.699 (1000.158 ms): pool-gsd-smart/3051 ... [continued]: clock_nanosleep()) = 0
4031.409 ( ): gpm/991 clock_nanosleep(rqtp: { .tv_sec: 2, .tv_nsec: 0 }, rmtp: 0x7ffcc6f73710) ...
10.133 (5000.375 ms): sleep/327642 ... [continued]: clock_nanosleep()) = 0
Performance counter stats for 'sleep 5':
2,617,347 cycles
1,855,997 instructions # 0.71 insn per cycle
5.002282128 seconds time elapsed
0.000855000 seconds user
0.000852000 seconds sys
#
perf annotate:
- Building with binutils' libopcode now is opt-in (BUILD_NONDISTRO=1) for
licensing reasons, and we missed a build test on tools/perf/tests makefile.
Since we now default to NDEBUG=1, we ended up segfaulting when building with
BUILD_NONDISTRO=1 because a needed initialization routine was being "error
checked" via an assert.
Fix it by explicitly checking the result and aborting instead if it fails.
We better back propagate the error, but at least 'perf annotate' on samples
collected for a BPF program is back working when perf is built with
BUILD_NONDISTRO=1.
perf report/top:
- Add back TUI hierarchy mode header, that is seen when using 'perf report/top --hierarchy'.
- Fix the number of entries for 'e' key in the TUI that was preventing navigation of
lines when expanding an entry.
perf report/script:
- Support cross platform register handling, allowing a perf.data file collected
on one architecture to have registers sampled correctly displayed when
analysis tools such as 'perf report' and 'perf script' are used on a different
architecture.
- Fix handling of event attributes in pipe mode, i.e. when one uses:
perf record -o - | perf report -i -
When no perf.data files are used.
- Handle files generated via pipe mode with a version of perf and then read
also via pipe mode with a different version of perf, where the event attr
record may have changed, use the record size field to properly support this
version mismatch.
perf probe:
- Accessing global variables from uprobes isn't supported, make the error
message state that instead of stating that some minimal kernel version is
needed to have that feature. This seems just a tool limitation, the kernel
probably has all that is needed.
perf tests:
- Fix a reference count related leak in the dlfilter v0 API where the result
of a thread__find_symbol_fb() is not matched with an addr_location__exit()
to drop the reference counts of the resolved components (machine, thread, map,
symbol, etc). Add a dlfilter test to make sure that doesn't regresses.
- Lots of fixes for the 'perf test' written in shell script related to problems
found with the shellcheck utility.
- Fixes for 'perf test' shell scripts testing features enabled when perf is
built with BUILD_BPF_SKEL=1, such as 'perf stat' bpf counters.
- Add perf record sample filtering test, things like the following example, that gets
implemented as a BPF filter attached to the event:
# perf record -e task-clock -c 10000 --filter 'ip < 0xffffffff00000000'
- Improve the way the task_analyzer test checks if libtraceevent is linked,
using 'perf version --build-options' instead of the more expensinve
'perf record -e "sched:sched_switch"'.
- Add support for riscv in the mmap-basic test. (This went as well via the RiscV tree, same contents).
libperf:
- Implement riscv mmap support (This went as well via the RiscV tree, same contents).
perf script:
- New tool that converts perf.data files to the firefox profiler format so that one can use
the visualizer at https://profiler.firefox.com/. Done by Anup Sharma as part of this year's
Google Summer of Code.
One can generate the output and upload it to the web interface but Anup also automated
everything:
perf script gecko -F 99 -a sleep 60
- Support syscall name parsing on arm64.
- Print "cgroup" field on the same line as "comm".
perf bench:
- Add new 'uprobe' benchmark to measure the overhead of uprobes with/without
BPF programs attached to it.
- breakpoints are not available on power9, skip that test.
perf stat:
- Add #num_cpus_online literal to be used in 'perf stat' metrics, and add this extra
'perf test' check that exemplifies its purpose:
TEST_ASSERT_VAL("#num_cpus_online",
expr__parse(&num_cpus_online, ctx, "#num_cpus_online") == 0);
TEST_ASSERT_VAL("#num_cpus", expr__parse(&num_cpus, ctx, "#num_cpus") == 0);
TEST_ASSERT_VAL("#num_cpus >= #num_cpus_online", num_cpus >= num_cpus_online);
Miscellaneous:
- Improve tool startup time by lazily reading PMU, JSON, sysfs data.
- Improve error reporting in the parsing of events, passing YYLTYPE to error routines,
so that the output can show were the parsing error was found.
- Add 'perf test' entries to check the parsing of events improvements.
- Fix various leak for things detected by -fsanitize=address, mostly things that would
be freed at tool exit, including:
- Free evsel->filter on the destructor.
- Allow tools to register a thread->priv destructor and use it in 'perf trace'.
- Free evsel->priv in 'perf trace'.
- Free string returned by synthesize_perf_probe_point() when the caller fails
to do all it needs.
- Adjust various compiler options to not consider errors some warnings when
building with broken headers found in things like python, flex, bison, as we
otherwise build with -Werror. Some for gcc, some for clang, some for some
specific version of those, some for some specific version of flex or bison, or
some specific combination of these components, bah.
- Allow customization of clang options for BPF target, this helps building on
gentoo where there are other oddities where BPF targets gets passed some compiler
options intended for the native build, so building with WERROR=0 helps while
these oddities are fixed.
- Dont pass ERR_PTR() values to perf_session__delete() in 'perf top' and 'perf lock',
fixing some segfaults when handling some odd failures.
- Add LTO build option.
- Fix format of unordered lists in the perf docs (tools/perf/Documentation).
- Overhaul the bison files, using constructs such as YYNOMEM.
- Remove unused tokens from the bison .y files.
- Add more comments to various structs.
- A few LoongArch enablement patches.
Vendor events (JSON):
- Add JSON metrics for Yitian 710 DDR (aarch64). Things like:
EventName, BriefDescription
visible_window_limit_reached_rd, "At least one entry in read queue reaches the visible window limit.",
visible_window_limit_reached_wr, "At least one entry in write queue reaches the visible window limit.",
op_is_dqsosc_mpc , "A DQS Oscillator MPC command to DRAM.",
op_is_dqsosc_mrr , "A DQS Oscillator MRR command to DRAM.",
op_is_tcr_mrr , "A Temperature Compensated Refresh(TCR) MRR command to DRAM.",
- Add AmpereOne metrics (aarch64).
- Update N2 and V2 metrics (aarch64) and events using Arm telemetry repo.
- Update scale units and descriptions of common topdown metrics on aarch64. Things like:
- "MetricExpr": "stall_slot_frontend / (#slots * cpu_cycles)",
- "BriefDescription": "Frontend bound L1 topdown metric",
+ "MetricExpr": "100 * (stall_slot_frontend / (#slots * cpu_cycles))",
+ "BriefDescription": "This metric is the percentage of total slots that were stalled due to resource constraints in the frontend of the processor.",
- Update events for intel: meteorlake to 1.04, sapphirerapids to 1.15, Icelake+ metric constraints.
- Update files for the power10 platform.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-tools-for-v6.6-1-2023-09-05' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools
Pull perf tools updates from Arnaldo Carvalho de Melo:
"perf tools maintainership:
- Add git information for perf-tools and perf-tools-next trees and
branches to the MAINTAINERS file. That is where development now
takes place and myself and Namhyung Kim have write access, more
people to come as we emulate other maintainer groups.
perf record:
- Record kernel data maps when 'perf record --data' is used, so that
global variables can be resolved and used in tools that do data
profiling.
perf trace:
- Remove the old, experimental support for BPF events in which a .c
file was passed as an event: "perf trace -e hello.c" to then get
compiled and loaded.
The only known usage for that, that shipped with the kernel as an
example for such events, augmented the raw_syscalls tracepoints and
was converted to a libbpf skeleton, reusing all the user space
components and the BPF code connected to the syscalls.
In the end just the way to glue the BPF part and the user space
type beautifiers changed, now being performed by libbpf skeletons.
The next step is to use BTF to do pretty printing of all syscall
types, as discussed with Alan Maguire and others.
Now, on a perf built with BUILD_BPF_SKEL=1 we get most if not all
path/filenames/strings, some of the networking data structures,
perf_event_attr, etc, i.e. systemwide tracing of nanosleep calls
and perf_event_open syscalls while 'perf stat' runs 'sleep' for 5
seconds:
# perf trace -a -e *nanosleep,perf* perf stat -e cycles,instructions sleep 5
0.000 ( 9.034 ms): perf/327641 perf_event_open(attr_uptr: { type: 0 (PERF_TYPE_HARDWARE), size: 136, config: 0 (PERF_COUNT_HW_CPU_CYCLES), sample_type: IDENTIFIER, read_format: TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING, disabled: 1, inherit: 1, enable_on_exec: 1, exclude_guest: 1 }, pid: 327642 (perf), cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = 3
9.039 ( 0.006 ms): perf/327641 perf_event_open(attr_uptr: { type: 0 (PERF_TYPE_HARDWARE), size: 136, config: 0x1 (PERF_COUNT_HW_INSTRUCTIONS), sample_type: IDENTIFIER, read_format: TOTAL_TIME_ENABLED|TOTAL_TIME_RUNNING, disabled: 1, inherit: 1, enable_on_exec: 1, exclude_guest: 1 }, pid: 327642 (perf-exec), cpu: -1, group_fd: -1, flags: FD_CLOEXEC) = 4
? ( ): gpm/991 ... [continued]: clock_nanosleep()) = 0
10.133 ( ): sleep/327642 clock_nanosleep(rqtp: { .tv_sec: 5, .tv_nsec: 0 }, rmtp: 0x7ffd36f83ed0) ...
? ( ): pool-gsd-smart/3051 ... [continued]: clock_nanosleep()) = 0
30.276 ( ): gpm/991 clock_nanosleep(rqtp: { .tv_sec: 2, .tv_nsec: 0 }, rmtp: 0x7ffcc6f73710) ...
223.215 (1000.430 ms): pool-gsd-smart/3051 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 0 }, rmtp: 0x7f6e7fffec90) = 0
30.276 (2000.394 ms): gpm/991 ... [continued]: clock_nanosleep()) = 0
1230.814 ( ): pool-gsd-smart/3051 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 0 }, rmtp: 0x7f6e7fffec90) ...
1230.814 (1000.404 ms): pool-gsd-smart/3051 ... [continued]: clock_nanosleep()) = 0
2030.886 ( ): gpm/991 clock_nanosleep(rqtp: { .tv_sec: 2, .tv_nsec: 0 }, rmtp: 0x7ffcc6f73710) ...
2237.709 (1000.153 ms): pool-gsd-smart/3051 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 0 }, rmtp: 0x7f6e7fffec90) = 0
? ( ): crond/1172 ... [continued]: clock_nanosleep()) = 0
3242.699 ( ): pool-gsd-smart/3051 clock_nanosleep(rqtp: { .tv_sec: 1, .tv_nsec: 0 }, rmtp: 0x7f6e7fffec90) ...
2030.886 (2000.385 ms): gpm/991 ... [continued]: clock_nanosleep()) = 0
3728.078 ( ): crond/1172 clock_nanosleep(rqtp: { .tv_sec: 60, .tv_nsec: 0 }, rmtp: 0x7ffe0971dcf0) ...
3242.699 (1000.158 ms): pool-gsd-smart/3051 ... [continued]: clock_nanosleep()) = 0
4031.409 ( ): gpm/991 clock_nanosleep(rqtp: { .tv_sec: 2, .tv_nsec: 0 }, rmtp: 0x7ffcc6f73710) ...
10.133 (5000.375 ms): sleep/327642 ... [continued]: clock_nanosleep()) = 0
Performance counter stats for 'sleep 5':
2,617,347 cycles
1,855,997 instructions # 0.71 insn per cycle
5.002282128 seconds time elapsed
0.000855000 seconds user
0.000852000 seconds sys
perf annotate:
- Building with binutils' libopcode now is opt-in (BUILD_NONDISTRO=1)
for licensing reasons, and we missed a build test on
tools/perf/tests makefile.
Since we now default to NDEBUG=1, we ended up segfaulting when
building with BUILD_NONDISTRO=1 because a needed initialization
routine was being "error checked" via an assert.
Fix it by explicitly checking the result and aborting instead if it
fails.
We better back propagate the error, but at least 'perf annotate' on
samples collected for a BPF program is back working when perf is
built with BUILD_NONDISTRO=1.
perf report/top:
- Add back TUI hierarchy mode header, that is seen when using 'perf
report/top --hierarchy'.
- Fix the number of entries for 'e' key in the TUI that was
preventing navigation of lines when expanding an entry.
perf report/script:
- Support cross platform register handling, allowing a perf.data file
collected on one architecture to have registers sampled correctly
displayed when analysis tools such as 'perf report' and 'perf
script' are used on a different architecture.
- Fix handling of event attributes in pipe mode, i.e. when one uses:
perf record -o - | perf report -i -
When no perf.data files are used.
- Handle files generated via pipe mode with a version of perf and
then read also via pipe mode with a different version of perf,
where the event attr record may have changed, use the record size
field to properly support this version mismatch.
perf probe:
- Accessing global variables from uprobes isn't supported, make the
error message state that instead of stating that some minimal
kernel version is needed to have that feature. This seems just a
tool limitation, the kernel probably has all that is needed.
perf tests:
- Fix a reference count related leak in the dlfilter v0 API where the
result of a thread__find_symbol_fb() is not matched with an
addr_location__exit() to drop the reference counts of the resolved
components (machine, thread, map, symbol, etc). Add a dlfilter test
to make sure that doesn't regresses.
- Lots of fixes for the 'perf test' written in shell script related
to problems found with the shellcheck utility.
- Fixes for 'perf test' shell scripts testing features enabled when
perf is built with BUILD_BPF_SKEL=1, such as 'perf stat' bpf
counters.
- Add perf record sample filtering test, things like the following
example, that gets implemented as a BPF filter attached to the
event:
# perf record -e task-clock -c 10000 --filter 'ip < 0xffffffff00000000'
- Improve the way the task_analyzer test checks if libtraceevent is
linked, using 'perf version --build-options' instead of the more
expensinve 'perf record -e "sched:sched_switch"'.
- Add support for riscv in the mmap-basic test. (This went as well
via the RiscV tree, same contents).
libperf:
- Implement riscv mmap support (This went as well via the RiscV tree,
same contents).
perf script:
- New tool that converts perf.data files to the firefox profiler
format so that one can use the visualizer at
https://profiler.firefox.com/. Done by Anup Sharma as part of this
year's Google Summer of Code.
One can generate the output and upload it to the web interface but
Anup also automated everything:
perf script gecko -F 99 -a sleep 60
- Support syscall name parsing on arm64.
- Print "cgroup" field on the same line as "comm".
perf bench:
- Add new 'uprobe' benchmark to measure the overhead of uprobes
with/without BPF programs attached to it.
- breakpoints are not available on power9, skip that test.
perf stat:
- Add #num_cpus_online literal to be used in 'perf stat' metrics, and
add this extra 'perf test' check that exemplifies its purpose:
TEST_ASSERT_VAL("#num_cpus_online",
expr__parse(&num_cpus_online, ctx, "#num_cpus_online") == 0);
TEST_ASSERT_VAL("#num_cpus", expr__parse(&num_cpus, ctx, "#num_cpus") == 0);
TEST_ASSERT_VAL("#num_cpus >= #num_cpus_online", num_cpus >= num_cpus_online);
Miscellaneous:
- Improve tool startup time by lazily reading PMU, JSON, sysfs data.
- Improve error reporting in the parsing of events, passing YYLTYPE
to error routines, so that the output can show were the parsing
error was found.
- Add 'perf test' entries to check the parsing of events
improvements.
- Fix various leak for things detected by -fsanitize=address, mostly
things that would be freed at tool exit, including:
- Free evsel->filter on the destructor.
- Allow tools to register a thread->priv destructor and use it in
'perf trace'.
- Free evsel->priv in 'perf trace'.
- Free string returned by synthesize_perf_probe_point() when the
caller fails to do all it needs.
- Adjust various compiler options to not consider errors some
warnings when building with broken headers found in things like
python, flex, bison, as we otherwise build with -Werror. Some for
gcc, some for clang, some for some specific version of those, some
for some specific version of flex or bison, or some specific
combination of these components, bah.
- Allow customization of clang options for BPF target, this helps
building on gentoo where there are other oddities where BPF targets
gets passed some compiler options intended for the native build, so
building with WERROR=0 helps while these oddities are fixed.
- Dont pass ERR_PTR() values to perf_session__delete() in 'perf top'
and 'perf lock', fixing some segfaults when handling some odd
failures.
- Add LTO build option.
- Fix format of unordered lists in the perf docs
(tools/perf/Documentation)
- Overhaul the bison files, using constructs such as YYNOMEM.
- Remove unused tokens from the bison .y files.
- Add more comments to various structs.
- A few LoongArch enablement patches.
Vendor events (JSON):
- Add JSON metrics for Yitian 710 DDR (aarch64). Things like:
EventName, BriefDescription
visible_window_limit_reached_rd, "At least one entry in read queue reaches the visible window limit.",
visible_window_limit_reached_wr, "At least one entry in write queue reaches the visible window limit.",
op_is_dqsosc_mpc , "A DQS Oscillator MPC command to DRAM.",
op_is_dqsosc_mrr , "A DQS Oscillator MRR command to DRAM.",
op_is_tcr_mrr , "A Temperature Compensated Refresh(TCR) MRR command to DRAM.",
- Add AmpereOne metrics (aarch64).
- Update N2 and V2 metrics (aarch64) and events using Arm telemetry
repo.
- Update scale units and descriptions of common topdown metrics on
aarch64. Things like:
- "MetricExpr": "stall_slot_frontend / (#slots * cpu_cycles)",
- "BriefDescription": "Frontend bound L1 topdown metric",
+ "MetricExpr": "100 * (stall_slot_frontend / (#slots * cpu_cycles))",
+ "BriefDescription": "This metric is the percentage of total slots that were stalled due to resource constraints in the frontend of the processor.",
- Update events for intel: meteorlake to 1.04, sapphirerapids to
1.15, Icelake+ metric constraints.
- Update files for the power10 platform"
* tag 'perf-tools-for-v6.6-1-2023-09-05' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (217 commits)
perf parse-events: Fix driver config term
perf parse-events: Fixes relating to no_value terms
perf parse-events: Fix propagation of term's no_value when cloning
perf parse-events: Name the two term enums
perf list: Don't print Unit for "default_core"
perf vendor events intel: Fix modifier in tma_info_system_mem_parallel_reads for skylake
perf dlfilter: Avoid leak in v0 API test use of resolve_address()
perf metric: Add #num_cpus_online literal
perf pmu: Remove str from perf_pmu_alias
perf parse-events: Make common term list to strbuf helper
perf parse-events: Minor help message improvements
perf pmu: Avoid uninitialized use of alias->str
perf jevents: Use "default_core" for events with no Unit
perf test stat_bpf_counters_cgrp: Enhance perf stat cgroup BPF counter test
perf test shell stat_bpf_counters: Fix test on Intel
perf test shell record_bpf_filter: Skip 6.2 kernel
libperf: Get rid of attr.id field
perf tools: Convert to perf_record_header_attr_id()
libperf: Add perf_record_header_attr_id()
perf tools: Handle old data in PERF_RECORD_ATTR
...
|
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|
Yonghong Song
|
ed5285a148 |
libbpf: Add __percpu_kptr macro definition
Add __percpu_kptr macro definition in bpf_helpers.h. Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20230827152800.1998492-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
3903802bb9 |
libbpf: Add basic BTF sanity validation
Implement a simple and straightforward BTF sanity check when parsing BTF data. Right now it's very basic and just validates that all the string offsets and type IDs are within valid range. For FUNC we also check that it points to FUNC_PROTO kinds. Even with such simple checks it fixes a bunch of crashes found by OSS fuzzer ([0]-[5]) and will allow fuzzer to make further progress. Some other invariants will be checked in follow up patches (like ensuring there is no infinite type loops), but this seems like a good start already. Adding FUNC -> FUNC_PROTO check revealed that one of selftests has a problem with FUNC pointing to VAR instead, so fix it up in the same commit. [0] https://github.com/libbpf/libbpf/issues/482 [1] https://github.com/libbpf/libbpf/issues/483 [2] https://github.com/libbpf/libbpf/issues/485 [3] https://github.com/libbpf/libbpf/issues/613 [4] https://github.com/libbpf/libbpf/issues/618 [5] https://github.com/libbpf/libbpf/issues/619 Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Alan Maguire <alan.maguire@oracle.com> Reviewed-by: Song Liu <song@kernel.org> Closes: https://github.com/libbpf/libbpf/issues/617 Link: https://lore.kernel.org/bpf/20230825202152.1813394-1-andrii@kernel.org |
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|
Linus Torvalds
|
e0152e7481 |
RISC-V Patches for the 6.6 Merge Window, Part 1
* Support for the new "riscv,isa-extensions" and "riscv,isa-base" device tree interfaces for probing extensions. * Support for userspace access to the performance counters. * Support for more instructions in kprobes. * Crash kernels can be allocated above 4GiB. * Support for KCFI. * Support for ELFs in !MMU configurations. * ARCH_KMALLOC_MINALIGN has been reduced to 8. * mmap() defaults to sv48-sized addresses, with longer addresses hidden behind a hint (similar to Arm and Intel). * Also various fixes and cleanups. -----BEGIN PGP SIGNATURE----- iQJHBAABCAAxFiEEKzw3R0RoQ7JKlDp6LhMZ81+7GIkFAmTx96kTHHBhbG1lckBk YWJiZWx0LmNvbQAKCRAuExnzX7sYiVjRD/9DYVLlkQ/OEDJjPaEcYCP49xgIVUUU lhs3XbSs2VNHBaiG114f6Q0AaT/uNi+uqSej3CeTmEot2kZkBk/f2yu+UNIriPZ9 GQiZsdyXhu921C+5VFtiI47KDWOVZ+Jpy3M1ll61IWt3yPSQHr1xOP0AOiyHHqe3 cmqpNnzjajlfVDoXPc2mGGzUJt/7ar4thcwnMNi98raXR5Qh7SP6rrHjoQhE1oFk LMP3CHqEAcHE2tE4CxZVpc6HOQ5m0LpQIOK7ypufGMyoIYESm5dt/JOT4MlhTtDw 6JzyVKtiM7lartUnUaW3ZoX4trQYT5gbXxWrJ2gCnUGy3VulikoXr1Rpz0qfdeOR XN8OLkVAqHfTGFI7oKk24f9Adw96R5NPZcdCay90h4J/kMfCiC7ZyUUI1XIa5iy1 np5pZCkf8HNcdywML7qcFd5n2O0wchyFnRLFZo6kJP9Ls5cEi6kBx/1jSdTcNgx/ fUKXyoEcriGoQiiwn29+4RZnU69gJV3zqQNLPpuwDQ5F/Q1zHTlrr+dqzezKkzcO dRTV2d2Q4A5vIDXPptzNNLlRQdrc8qxPJ1lxQVkPIU4/mtqczmZBwlyY2u9zwPyS sehJgJZnoAf+jm71NgQAKLck4MUBsMnMogOWunhXkVRCoZlbbkUWX4ECZYwPKsVk W7zVPmLvSM0l5g== =/tXb -----END PGP SIGNATURE----- Merge tag 'riscv-for-linus-6.6-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for the new "riscv,isa-extensions" and "riscv,isa-base" device tree interfaces for probing extensions - Support for userspace access to the performance counters - Support for more instructions in kprobes - Crash kernels can be allocated above 4GiB - Support for KCFI - Support for ELFs in !MMU configurations - ARCH_KMALLOC_MINALIGN has been reduced to 8 - mmap() defaults to sv48-sized addresses, with longer addresses hidden behind a hint (similar to Arm and Intel) - Also various fixes and cleanups * tag 'riscv-for-linus-6.6-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits) lib/Kconfig.debug: Restrict DEBUG_INFO_SPLIT for RISC-V riscv: support PREEMPT_DYNAMIC with static keys riscv: Move create_tmp_mapping() to init sections riscv: Mark KASAN tmp* page tables variables as static riscv: mm: use bitmap_zero() API riscv: enable DEBUG_FORCE_FUNCTION_ALIGN_64B riscv: remove redundant mv instructions RISC-V: mm: Document mmap changes RISC-V: mm: Update pgtable comment documentation RISC-V: mm: Add tests for RISC-V mm RISC-V: mm: Restrict address space for sv39,sv48,sv57 riscv: enable DMA_BOUNCE_UNALIGNED_KMALLOC for !dma_coherent riscv: allow kmalloc() caches aligned to the smallest value riscv: support the elf-fdpic binfmt loader binfmt_elf_fdpic: support 64-bit systems riscv: Allow CONFIG_CFI_CLANG to be selected riscv/purgatory: Disable CFI riscv: Add CFI error handling riscv: Add ftrace_stub_graph riscv: Add types to indirectly called assembly functions ... |
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Namhyung Kim
|
c091c78b73 |
libperf: Get rid of attr.id field
Now there's no in-tree user of the field. To remove the possible bug later, let's get rid of the 'id' field and add a comment for that. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20230825152552.112913-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
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Namhyung Kim
|
baec60800d |
libperf: Add perf_record_header_attr_id()
The HEADER_ATTR record has an event attr followed by the id array. But perf data from a different version could have different size of attr. So it cannot just use event->attr.id to access the array. Let's add the perf_record_header_attr_id() macro to calculate the start of the array. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20230825152552.112913-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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Andrii Nakryiko
|
f3bdb54f09 |
libbpf: fix signedness determination in CO-RE relo handling logic
Extracting btf_int_encoding() is only meaningful for BTF_KIND_INT, so we need to check that first before inferring signedness. Closes: https://github.com/libbpf/libbpf/issues/704 Reported-by: Lorenz Bauer <lmb@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20230824000016.2658017-2-andrii@kernel.org Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
||
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Daniel Xu
|
068ca522d5 |
libbpf: Add bpf_object__unpin()
For bpf_object__pin_programs() there is bpf_object__unpin_programs(). Likewise bpf_object__unpin_maps() for bpf_object__pin_maps(). But no bpf_object__unpin() for bpf_object__pin(). Adding the former adds symmetry to the API. It's also convenient for cleanup in application code. It's an API I would've used if it was available for a repro I was writing earlier. Signed-off-by: Daniel Xu <dxu@dxuuu.xyz> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/b2f9d41da4a350281a0b53a804d11b68327e14e5.1692832478.git.dxu@dxuuu.xyz |
||
Hao Luo
|
29d67fdebc |
libbpf: Free btf_vmlinux when closing bpf_object
I hit a memory leak when testing bpf_program__set_attach_target(). Basically, set_attach_target() may allocate btf_vmlinux, for example, when setting attach target for bpf_iter programs. But btf_vmlinux is freed only in bpf_object_load(), which means if we only open bpf object but not load it, setting attach target may leak btf_vmlinux. So let's free btf_vmlinux in bpf_object__close() anyway. Signed-off-by: Hao Luo <haoluo@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20230822193840.1509809-1-haoluo@google.com |
||
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Jiri Olsa
|
5902da6d8a |
libbpf: Add uprobe multi link support to bpf_program__attach_usdt
Adding support for usdt_manager_attach_usdt to use uprobe_multi link to attach to usdt probes. The uprobe_multi support is detected before the usdt program is loaded and its expected_attach_type is set accordingly. If uprobe_multi support is detected the usdt_manager_attach_usdt gathers uprobes info and calls bpf_program__attach_uprobe to create all needed uprobes. If uprobe_multi support is not detected the old behaviour stays. Also adding usdt.s program section for sleepable usdt probes. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230809083440.3209381-18-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Jiri Olsa
|
7e1b468123 |
libbpf: Add uprobe multi link detection
Adding uprobe-multi link detection. It will be used later in bpf_program__attach_usdt function to check and use uprobe_multi link over standard uprobe links. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230809083440.3209381-17-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
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Jiri Olsa
|
5bfdd32dd5 |
libbpf: Add support for u[ret]probe.multi[.s] program sections
Adding support for several uprobe_multi program sections to allow auto attach of multi_uprobe programs. Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230809083440.3209381-16-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
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Jiri Olsa
|
3140cf121c |
libbpf: Add bpf_program__attach_uprobe_multi function
Adding bpf_program__attach_uprobe_multi function that
allows to attach multiple uprobes with uprobe_multi link.
The user can specify uprobes with direct arguments:
binary_path/func_pattern/pid
or with struct bpf_uprobe_multi_opts opts argument fields:
const char **syms;
const unsigned long *offsets;
const unsigned long *ref_ctr_offsets;
const __u64 *cookies;
User can specify 2 mutually exclusive set of inputs:
1) use only path/func_pattern/pid arguments
2) use path/pid with allowed combinations of:
syms/offsets/ref_ctr_offsets/cookies/cnt
- syms and offsets are mutually exclusive
- ref_ctr_offsets and cookies are optional
Any other usage results in error.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230809083440.3209381-15-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
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Jiri Olsa
|
5054a303f8 |
libbpf: Add bpf_link_create support for multi uprobes
Adding new uprobe_multi struct to bpf_link_create_opts object to pass multiple uprobe data to link_create attr uapi. Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230809083440.3209381-14-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
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Jiri Olsa
|
e613d1d0f7 |
libbpf: Add elf_resolve_pattern_offsets function
Adding elf_resolve_pattern_offsets function that looks up offsets for symbols specified by pattern argument. The 'pattern' argument allows wildcards (*?' supported). Offsets are returned in allocated array together with its size and needs to be released by the caller. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230809083440.3209381-13-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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Jiri Olsa
|
7ace84c689 |
libbpf: Add elf_resolve_syms_offsets function
Adding elf_resolve_syms_offsets function that looks up offsets for symbols specified in syms array argument. Offsets are returned in allocated array with the 'cnt' size, that needs to be released by the caller. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230809083440.3209381-12-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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Jiri Olsa
|
3774705db1 |
libbpf: Add elf symbol iterator
Adding elf symbol iterator object (and some functions) that follow
open-coded iterator pattern and some functions to ease up iterating
elf object symbols.
The idea is to iterate single symbol section with:
struct elf_sym_iter iter;
struct elf_sym *sym;
if (elf_sym_iter_new(&iter, elf, binary_path, SHT_DYNSYM))
goto error;
while ((sym = elf_sym_iter_next(&iter))) {
...
}
I considered opening the elf inside the iterator and iterate all symbol
sections, but then it gets more complicated wrt user checks for when
the next section is processed.
Plus side is the we don't need 'exit' function, because caller/user is
in charge of that.
The returned iterated symbol object from elf_sym_iter_next function
is placed inside the struct elf_sym_iter, so no extra allocation or
argument is needed.
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230809083440.3209381-11-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
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Jiri Olsa
|
f90eb70d44 |
libbpf: Add elf_open/elf_close functions
Adding elf_open/elf_close functions and using it in elf_find_func_offset_from_file function. It will be used in following changes to save some common code. Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230809083440.3209381-10-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Jiri Olsa
|
5c74272504 |
libbpf: Move elf_find_func_offset* functions to elf object
Adding new elf object that will contain elf related functions. There's no functional change. Suggested-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230809083440.3209381-9-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
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Jiri Olsa
|
8097e460ca |
libbpf: Add uprobe_multi attach type and link names
Adding new uprobe_multi attach type and link names, so the functions can resolve the new values. Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230809083440.3209381-8-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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Dave Marchevsky
|
5964a223f5 |
libbpf: Support triple-underscore flavors for kfunc relocation
The function signature of kfuncs can change at any time due to their
intentional lack of stability guarantees. As kfuncs become more widely
used, BPF program writers will need facilities to support calling
different versions of a kfunc from a single BPF object. Consider this
simplified example based on a real scenario we ran into at Meta:
/* initial kfunc signature */
int some_kfunc(void *ptr)
/* Oops, we need to add some flag to modify behavior. No problem,
change the kfunc. flags = 0 retains original behavior */
int some_kfunc(void *ptr, long flags)
If the initial version of the kfunc is deployed on some portion of the
fleet and the new version on the rest, a fleetwide service that uses
some_kfunc will currently need to load different BPF programs depending
on which some_kfunc is available.
Luckily CO-RE provides a facility to solve a very similar problem,
struct definition changes, by allowing program writers to declare
my_struct___old and my_struct___new, with ___suffix being considered a
'flavor' of the non-suffixed name and being ignored by
bpf_core_type_exists and similar calls.
This patch extends the 'flavor' facility to the kfunc extern
relocation process. BPF program writers can now declare
extern int some_kfunc___old(void *ptr)
extern int some_kfunc___new(void *ptr, int flags)
then test which version of the kfunc exists with bpf_ksym_exists.
Relocation and verifier's dead code elimination will work in concert as
expected, allowing this pattern:
if (bpf_ksym_exists(some_kfunc___old))
some_kfunc___old(ptr);
else
some_kfunc___new(ptr, 0);
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: David Vernet <void@manifault.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230817225353.2570845-1-davemarchevsky@fb.com
|
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|
Alexandre Ghiti
|
60bd501164
|
tools: lib: perf: Implement riscv mmap support
riscv now supports mmaping hardware counters so add what's needed to take advantage of that in libperf. Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Ian Rogers <irogers@google.com> |
||
|
Alexandre Ghiti
|
159a8bb06f |
libperf: Implement riscv mmap support
riscv now supports mmaping hardware counters so add what's needed to take advantage of that in libperf. Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Ian Rogers <irogers@google.com> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Anup Patel <anup@brainfault.org> Cc: Atish Patra <atishp@atishpatra.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rob Herring <robh@kernel.org> Cc: Rémi Denis-Courmont <remi@remlab.net> Cc: Will Deacon <will@kernel.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: linux-riscv@lists.infradead.org Link: https://lore.kernel.org/r/20230802080328.1213905-10-alexghiti@rivosinc.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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Marco Vedovati
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8e50750f12 |
libbpf: Set close-on-exec flag on gzopen
Enable the close-on-exec flag when using gzopen. This is especially important for multithreaded programs making use of libbpf, where a fork + exec could race with libbpf library calls, potentially resulting in a file descriptor leaked to the new process. This got missed in |
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Sergey Kacheev
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dde3979bb3 |
libbpf: Use local includes inside the library
In our monrepo, we try to minimize special processing when importing (aka vendor) third-party source code. Ideally, we try to import directly from the repositories with the code without changing it, we try to stick to the source code dependency instead of the artifact dependency. In the current situation, a patch has to be made for libbpf to fix the includes in bpf headers so that they work directly from libbpf/src. Signed-off-by: Sergey Kacheev <s.kacheev@gmail.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/CAJVhQqUg6OKq6CpVJP5ng04Dg+z=igevPpmuxTqhsR3dKvd9+Q@mail.gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
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Randy Dunlap
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94e38c956b |
libbpf: fix typos in Makefile
Capitalize ABI (acronym) and fix spelling of "destination".
Fixes:
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Jakub Kicinski
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59be3baa8d |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. No conflicts or adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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Daniel Borkmann
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4e9c2d9af5 |
libbpf: Add helper macro to clear opts structs
Add a small and generic LIBBPF_OPTS_RESET() helper macros which clears an opts structure and reinitializes its .sz member to place the structure size. Additionally, the user can pass option-specific data to reinitialize via varargs. I found this very useful when developing selftests, but it is also generic enough as a macro next to the existing LIBBPF_OPTS() which hides the .sz initialization, too. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20230719140858.13224-6-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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Daniel Borkmann
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55cc376847 |
libbpf: Add link-based API for tcx
Implement tcx BPF link support for libbpf. The bpf_program__attach_fd() API has been refactored slightly in order to pass bpf_link_create_opts pointer as input. A new bpf_program__attach_tcx() has been added on top of this which allows for passing all relevant data via extensible struct bpf_tcx_opts. The program sections tcx/ingress and tcx/egress correspond to the hook locations for tc ingress and egress, respectively. For concrete usage examples, see the extensive selftests that have been developed as part of this series. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230719140858.13224-5-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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Daniel Borkmann
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fe20ce3a51 |
libbpf: Add opts-based attach/detach/query API for tcx
Extend libbpf attach opts and add a new detach opts API so this can be used to add/remove fd-based tcx BPF programs. The old-style bpf_prog_detach() and bpf_prog_detach2() APIs are refactored to reuse the new bpf_prog_detach_opts() internally. The bpf_prog_query_opts() API got extended to be able to handle the new link_ids, link_attach_flags and revision fields. For concrete usage examples, see the extensive selftests that have been developed as part of this series. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230719140858.13224-4-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov <ast@kernel.org> |