linux/tools
Alan Maguire 920d16af9b libbpf: BTF dumper support for typed data
Add a BTF dumper for typed data, so that the user can dump a typed
version of the data provided.

The API is

int btf_dump__dump_type_data(struct btf_dump *d, __u32 id,
                             void *data, size_t data_sz,
                             const struct btf_dump_type_data_opts *opts);

...where the id is the BTF id of the data pointed to by the "void *"
argument; for example the BTF id of "struct sk_buff" for a
"struct skb *" data pointer.  Options supported are

 - a starting indent level (indent_lvl)
 - a user-specified indent string which will be printed once per
   indent level; if NULL, tab is chosen but any string <= 32 chars
   can be provided.
 - a set of boolean options to control dump display, similar to those
   used for BPF helper bpf_snprintf_btf().  Options are
        - compact : omit newlines and other indentation
        - skip_names: omit member names
        - emit_zeroes: show zero-value members

Default output format is identical to that dumped by bpf_snprintf_btf(),
for example a "struct sk_buff" representation would look like this:

struct sk_buff){
	(union){
		(struct){
			.next = (struct sk_buff *)0xffffffffffffffff,
			.prev = (struct sk_buff *)0xffffffffffffffff,
		(union){
			.dev = (struct net_device *)0xffffffffffffffff,
			.dev_scratch = (long unsigned int)18446744073709551615,
		},
	},
...

If the data structure is larger than the *data_sz*
number of bytes that are available in *data*, as much
of the data as possible will be dumped and -E2BIG will
be returned.  This is useful as tracers will sometimes
not be able to capture all of the data associated with
a type; for example a "struct task_struct" is ~16k.
Being able to specify that only a subset is available is
important for such cases.  On success, the amount of data
dumped is returned.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1626362126-27775-2-git-send-email-alan.maguire@oracle.com
2021-07-16 13:46:59 -07:00
..
accounting
arch tools headers UAPI: Synch KVM's svm.h header with the kernel 2021-07-01 16:14:37 -03:00
bootconfig bootconfig: Share the checksum function with tools 2021-06-10 13:41:26 -04:00
bpf tools: bpf: Fix error in 'make -C tools/ bpf_install' 2021-07-07 14:06:38 -07:00
build tools build: Fix quiet cmd indentation 2021-05-17 12:10:03 +09:00
cgroup tools/cgroup/slabinfo.py: updated to work on current kernel 2021-04-23 14:42:40 -07:00
debugging tools: Fix "the the" in a message in kernel-chktaint 2021-06-13 17:01:17 -06:00
edid
firewire
firmware
gpio
hv
iio
include Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2021-07-15 22:40:10 -07:00
io_uring
kvm/kvm_stat tools/kvm_stat: Fix documentation typo 2021-05-07 06:06:22 -04:00
laptop
leds
lib libbpf: BTF dumper support for typed data 2021-07-16 13:46:59 -07:00
memory-model tools/memory-model: Fix smp_mb__after_spinlock() spelling 2021-05-10 16:27:20 -07:00
objtool A single ELF format fix for a section flags mismatch bug that breaks 2021-06-28 11:35:55 -07:00
pci
pcmcia
perf perf test: Add free() calls for scandir() returned dirent entries 2021-07-09 15:34:41 -03:00
power tools/power/x86/intel-speed-select: v1.10 release 2021-06-18 15:29:32 +02:00
rcu tools/rcu: Add drgn script to dump number of RCU callbacks 2021-05-10 15:39:19 -07:00
scripts tools build: Fix quiet cmd indentation 2021-05-17 12:10:03 +09:00
spi spi: tools: make a symbolic link to the header file spi.h 2021-04-22 16:30:39 +01:00
testing selftests/bpf: Switch existing selftests to using open_opts for custom BTF 2021-07-16 13:22:47 -07:00
thermal/tmon tools: do not include scripts/Kbuild.include 2021-04-25 05:26:13 +09:00
time
tracing
usb treewide: remove editor modelines and cruft 2021-05-07 00:26:34 -07:00
virtio
vm tools/vm/page_owner_sort.c: check malloc() return 2021-06-29 10:53:47 -07:00
wmi
Makefile