The "stack_trace_filter" file only makes sense if DYNAMIC_FTRACE is
configured in. If it is not, then the user can not filter any functions.
Not only that, the open function causes warnings when DYNAMIC_FTRACE is not
set.
Link: http://lkml.kernel.org/r/20170710110521.600806-1-arnd@arndb.de
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The addition of TGID to the tracing header added a check to see if TGID
shoudl be displayed or not, and updated the header accordingly.
Unfortunately, it broke the default header.
Also add constant strings to use for spacing. This does remove the
visibility of the header a bit, but cuts it down from the extended lines
much greater than 80 characters.
Before this change:
# tracer: function
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU#|||| TIMESTAMP FUNCTION
# | | | |||| | |
swapper/0-1 [000] .... 0.277830: migration_init <-do_one_initcall
swapper/0-1 [002] d... 13.861967: Unknown type 1201
swapper/0-1 [002] d..1 13.861970: Unknown type 1202
After this change:
# tracer: function
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
swapper/0-1 [000] .... 0.278245: migration_init <-do_one_initcall
swapper/0-1 [003] d... 13.861189: Unknown type 1201
swapper/0-1 [003] d..1 13.861192: Unknown type 1202
Cc: Joel Fernandes <joelaf@google.com>
Fixes: 441dae8f2f ("tracing: Add support for display of tgid in trace output")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When we derive event names, convert some expected symbols (such as ':'
used to specify module:name and '.' present in some symbols) into
underscores so that the event name is not rejected.
Before this patch:
# echo 'p kobject_example:foo_store' > kprobe_events
trace_kprobe: Failed to allocate trace_probe.(-22)
-sh: write error: Invalid argument
After this patch:
# echo 'p kobject_example:foo_store' > kprobe_events
# cat kprobe_events
p:kprobes/p_kobject_example_foo_store_0 kobject_example:foo_store
Link: http://lkml.kernel.org/r/66c189e09e71361aba91dd4a5bd146a1b62a7a51.1499453040.git.naveen.n.rao@linux.vnet.ibm.com
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As writing into stack_trace_filter, the iter-tr is not set and is NULL.
Check if it is NULL before dereferencing it in ftrace_regex_release().
Fixes: 8c08f0d5c6 ("ftrace: Have cached module filters be an active filter")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Need to get the changes from 0f17976568 ("ftrace: Fix regression with
module command in stack_trace_filter") as it is required to fix some other
changes with stack_trace_filter and the new development code.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When doing the following command:
# echo ":mod:kvm_intel" > /sys/kernel/tracing/stack_trace_filter
it triggered a crash.
This happened with the clean up of probes. It required all callers to the
regex function (doing ftrace filtering) to have ops->private be a pointer to
a trace_array. But for the stack tracer, that is not the case.
Allow for the ops->private to be NULL, and change the function command
callbacks to handle the trace_array pointer being NULL as well.
Fixes: d2afd57a4b ("tracing/ftrace: Allow instances to have their own function probes")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Init boot up functions may be traced, but they are also freed when the
kernel finishes booting. These are removed from the ftrace tables, and the
debug variable for dyn_ftrace_total_info needs to reflect that as well.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If the new_hash fails to allocate, then unlock the hash mutex on error.
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Inorder to support recording of tgid, the following changes are made:
* Introduce a new API (tracing_record_taskinfo) to additionally record the tgid
along with the task's comm at the same time. This has has the benefit of not
setting trace_cmdline_save before all the information for a task is saved.
* Add a new API tracing_record_taskinfo_sched_switch to record task information
for 2 tasks at a time (previous and next) and use it from sched_switch probe.
* Preserve the old API (tracing_record_cmdline) and create it as a wrapper
around the new one so that existing callers aren't affected.
* Reuse the existing sched_switch and sched_wakeup probes to record tgid
information and add a new option 'record-tgid' to enable recording of tgid
When record-tgid option isn't enabled to being with, we take care to make sure
that there's isn't memory or runtime overhead.
Link: http://lkml.kernel.org/r/20170627020155.5139-1-joelaf@google.com
Cc: kernel-team@android.com
Cc: Ingo Molnar <mingo@redhat.com>
Tested-by: Michael Sartain <mikesart@gmail.com>
Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The dyn_ftrace_total_info file is used to show how many functions have been
converted into nops and can be used by ftrace. The problem is that it does
not get decremented when functions are removed (init boot code being freed,
and modules being freed). That means the number is very inaccurate everytime
functions are removed from the ftrace tables. Decrement it when functions
are removed.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace_arch_read_dyn_info() was used so that archs could add its own debug
information into the dyn_ftrace_total_info in the tracefs file system. That
file is for debugging usage of dynamic ftrace. No arch uses that function
anymore, so just get rid of it.
This also allows for tracing_read_dyn_info() to be cleaned up a bit.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When a module filter is added to set_ftrace_filter, if the module is not
loaded, it is cached. This should be considered an active filter, and
function tracing should be filtered by this. That is, if a cached module
filter is the only filter set, then no function tracing should be happening,
as all the functions available will be filtered out.
This makes sense, as the reason to add a cached module filter, is to trace
the module when you load it. There shouldn't be any other tracing happening
until then.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If a module is cached in the set_ftrace_filter, and that module is loaded,
then enable tracing on that module as if the cached module text was written
into set_ftrace_filter just as the module is loaded.
# echo ":mod:kvm_intel" >
# cat /sys/kernel/tracing/set_ftrace_filter
#### all functions enabled ####
:mod:kvm_intel
# modprobe kvm_intel
# cat /sys/kernel/tracing/set_ftrace_filter
vmx_get_rflags [kvm_intel]
vmx_get_pkru [kvm_intel]
vmx_get_interrupt_shadow [kvm_intel]
vmx_rdtscp_supported [kvm_intel]
vmx_invpcid_supported [kvm_intel]
[..]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When writing in a module filter into set_ftrace_filter for a module that is
not yet loaded, it it cached, and will be executed when the module is loaded
(although that is not implemented yet at this commit). Display the list of
cached modules to be traced.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This is the start of the infrastructure work to allow for tracing module
functions before it is loaded.
Currently the following command:
# echo :mod:some-mod > set_ftrace_filter
will enable tracing of all functions within the module "some-mod" if it is
loaded. What we want, is if the module is not loaded, that line will be
saved. When the module is loaded, then the "some-mod" will have that line
executed on it, so that the functions within it starts being traced.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull tracing fixes from Steven Rostedt:
- Fix a bug caused by not cleaning up the new instance unique triggers
when deleting an instance. It also creates a selftest that triggers
that bug.
- Fix the delayed optimization happening after kprobes boot up self
tests being removed by freeing of init memory.
- Comment kprobes on why the delay optimization is not a problem for
removal of modules, to keep other developers from searching that
riddle.
- Fix another case of rcu not watching in stack trace tracing.
* tag 'trace-v4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Make sure RCU is watching before calling a stack trace
kprobes: Document how optimized kprobes are removed from module unload
selftests/ftrace: Add test to remove instance with active event triggers
selftests/ftrace: Fix bashisms
ftrace: Remove #ifdef from code and add clear_ftrace_function_probes() stub
ftrace/instances: Clear function triggers when removing instances
ftrace: Simplify glob handling in unregister_ftrace_function_probe_func()
tracing/kprobes: Enforce kprobes teardown after testing
tracing: Move postpone selftests to core from early_initcall
Pull block fixes from Jens Axboe:
"A small collection of fixes that should go into this cycle.
- a pull request from Christoph for NVMe, which ended up being
manually applied to avoid pulling in newer bits in master. Mostly
fibre channel fixes from James, but also a few fixes from Jon and
Vijay
- a pull request from Konrad, with just a single fix for xen-blkback
from Gustavo.
- a fuseblk bdi fix from Jan, fixing a regression in this series with
the dynamic backing devices.
- a blktrace fix from Shaohua, replacing sscanf() with kstrtoull().
- a request leak fix for drbd from Lars, fixing a regression in the
last series with the kref changes. This will go to stable as well"
* 'for-linus' of git://git.kernel.dk/linux-block:
nvmet: release the sq ref on rdma read errors
nvmet-fc: remove target cpu scheduling flag
nvme-fc: stop queues on error detection
nvme-fc: require target or discovery role for fc-nvme targets
nvme-fc: correct port role bits
nvme: unmap CMB and remove sysfs file in reset path
blktrace: fix integer parse
fuseblk: Fix warning in super_setup_bdi_name()
block: xen-blkback: add null check to avoid null pointer dereference
drbd: fix request leak introduced by locking/atomic, kref: Kill kref_sub()
sscanf is a very poor way to parse integer. For example, I input
"discard" for act_mask, it gets 0xd and completely messes up. Using
correct API to do integer parse.
This patch also makes attributes accept any base of integer.
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Enabling the tracer selftest triggers occasionally the warning in
text_poke(), which warns when the to be modified page is not marked
reserved.
The reason is that the tracer selftest installs kprobes on functions marked
__init for testing. These probes are removed after the tests, but that
removal schedules the delayed kprobes_optimizer work, which will do the
actual text poke. If the work is executed after the init text is freed,
then the warning triggers. The bug can be reproduced reliably when the work
delay is increased.
Flush the optimizer work and wait for the optimizing/unoptimizing lists to
become empty before returning from the kprobes tracer selftest. That
ensures that all operations which were queued due to the probes removal
have completed.
Link: http://lkml.kernel.org/r/20170516094802.76a468bb@gandalf.local.home
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 6274de498 ("kprobes: Support delayed unoptimizing")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull tracing fix from Steven Rostedt:
"This is a trivial patch that changes a check for a cpumask from a NULL
pointer to using cpumask_available(), which will do the check. This is
because cpumasks when not allocated are always set, and clang
complains about it"
* tag 'trace-v4.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Use cpumask_available() to check if cpumask variable may be used
Pull more tracing updates from Steven Rostedt:
"These are three simple changes.
The first one is just a switch from using strcpy() to strlcpy().
Someone thought that it may cause an overflow bug, but since it only
copies comms into a pre-allocated array of TASK_COMM_LEN, and no comm
should ever be bigger than that, nor not end with a nul character,
this change is more of a safety precaution than fixing anything that
is actually broken.
The other two changes are simply cleaning and optimizing some code"
* tag 'trace-v4.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Simplify ftrace_match_record() even more
ftrace: Remove an unneeded condition
tracing: Use strlcpy() instead of strcpy() in __trace_find_cmdline()
Dan Carpenter sent a patch to remove a check in ftrace_match_record()
because the logic of the code made the check redundant. I looked deeper into
the code, and made the following logic table, with the three variables and
the result of the original code.
modname mod_matches exclude_mod result
------- ----------- ----------- ------
0 0 0 return 0
0 0 1 func_match
0 1 * < cannot exist >
1 0 0 return 0
1 0 1 func_match
1 1 0 func_match
1 1 1 return 0
Notice that when mod_matches == exclude mod, the result is always to
return 0, and when mod_matches != exclude_mod, then the result is to test
the function. This means we only need test if mod_matches is equal to
exclude_mod.
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull tracing updates from Steven Rostedt:
"New features for this release:
- Pretty much a full rewrite of the processing of function plugins.
i.e. echo do_IRQ:stacktrace > set_ftrace_filter
- The rewrite was needed to add plugins to be unique to tracing
instances. i.e. mkdir instance/foo; cd instances/foo; echo
do_IRQ:stacktrace > set_ftrace_filter The old way was written very
hacky. This removes a lot of those hacks.
- New "function-fork" tracing option. When set, pids in the
set_ftrace_pid will have their children added when the processes
with their pids listed in the set_ftrace_pid file forks.
- Exposure of "maxactive" for kretprobe in kprobe_events
- Allow for builtin init functions to be traced by the function
tracer (via the kernel command line). Module init function tracing
will come in the next release.
- Added more selftests, and have selftests also test in an instance"
* tag 'trace-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (60 commits)
ring-buffer: Return reader page back into existing ring buffer
selftests: ftrace: Allow some event trigger tests to run in an instance
selftests: ftrace: Have some basic tests run in a tracing instance too
selftests: ftrace: Have event tests also run in an tracing instance
selftests: ftrace: Make func_event_triggers and func_traceonoff_triggers tests do instances
selftests: ftrace: Allow some tests to be run in a tracing instance
tracing/ftrace: Allow for instances to trigger their own stacktrace probes
tracing/ftrace: Allow for the traceonoff probe be unique to instances
tracing/ftrace: Enable snapshot function trigger to work with instances
tracing/ftrace: Allow instances to have their own function probes
tracing/ftrace: Add a better way to pass data via the probe functions
ftrace: Dynamically create the probe ftrace_ops for the trace_array
tracing: Pass the trace_array into ftrace_probe_ops functions
tracing: Have the trace_array hold the list of registered func probes
ftrace: If the hash for a probe fails to update then free what was initialized
ftrace: Have the function probes call their own function
ftrace: Have each function probe use its own ftrace_ops
ftrace: Have unregister_ftrace_function_probe_func() return a value
ftrace: Add helper function ftrace_hash_move_and_update_ops()
ftrace: Remove data field from ftrace_func_probe structure
...
Pull networking updates from David Millar:
"Here are some highlights from the 2065 networking commits that
happened this development cycle:
1) XDP support for IXGBE (John Fastabend) and thunderx (Sunil Kowuri)
2) Add a generic XDP driver, so that anyone can test XDP even if they
lack a networking device whose driver has explicit XDP support
(me).
3) Sparc64 now has an eBPF JIT too (me)
4) Add a BPF program testing framework via BPF_PROG_TEST_RUN (Alexei
Starovoitov)
5) Make netfitler network namespace teardown less expensive (Florian
Westphal)
6) Add symmetric hashing support to nft_hash (Laura Garcia Liebana)
7) Implement NAPI and GRO in netvsc driver (Stephen Hemminger)
8) Support TC flower offload statistics in mlxsw (Arkadi Sharshevsky)
9) Multiqueue support in stmmac driver (Joao Pinto)
10) Remove TCP timewait recycling, it never really could possibly work
well in the real world and timestamp randomization really zaps any
hint of usability this feature had (Soheil Hassas Yeganeh)
11) Support level3 vs level4 ECMP route hashing in ipv4 (Nikolay
Aleksandrov)
12) Add socket busy poll support to epoll (Sridhar Samudrala)
13) Netlink extended ACK support (Johannes Berg, Pablo Neira Ayuso,
and several others)
14) IPSEC hw offload infrastructure (Steffen Klassert)"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2065 commits)
tipc: refactor function tipc_sk_recv_stream()
tipc: refactor function tipc_sk_recvmsg()
net: thunderx: Optimize page recycling for XDP
net: thunderx: Support for XDP header adjustment
net: thunderx: Add support for XDP_TX
net: thunderx: Add support for XDP_DROP
net: thunderx: Add basic XDP support
net: thunderx: Cleanup receive buffer allocation
net: thunderx: Optimize CQE_TX handling
net: thunderx: Optimize RBDR descriptor handling
net: thunderx: Support for page recycling
ipx: call ipxitf_put() in ioctl error path
net: sched: add helpers to handle extended actions
qed*: Fix issues in the ptp filter config implementation.
qede: Fix concurrency issue in PTP Tx path processing.
stmmac: Add support for SIMATIC IOT2000 platform
net: hns: fix ethtool_get_strings overflow in hns driver
tcp: fix wraparound issue in tcp_lp
bpf, arm64: fix jit branch offset related to ldimm64
bpf, arm64: implement jiting of BPF_XADD
...