Commit Graph

372 Commits

Author SHA1 Message Date
Ian Rogers
ee756ef749 perf dso: Add reference count checking and accessor functions
Add reference count checking to struct dso, this can help with
implementing correct reference counting discipline. To avoid
RC_CHK_ACCESS everywhere, add accessor functions for the variables in
struct dso.

The majority of the change is mechanical in nature and not easy to
split up.

Committer testing:

'perf test' up to this patch shows no regressions.

But:

  util/symbol.c: In function ‘dso__load_bfd_symbols’:
  util/symbol.c:1683:9: error: too few arguments to function ‘dso__set_adjust_symbols’
   1683 |         dso__set_adjust_symbols(dso);
        |         ^~~~~~~~~~~~~~~~~~~~~~~
  In file included from util/symbol.c:21:
  util/dso.h:268:20: note: declared here
    268 | static inline void dso__set_adjust_symbols(struct dso *dso, bool val)
        |                    ^~~~~~~~~~~~~~~~~~~~~~~
  make[6]: *** [/home/acme/git/perf-tools-next/tools/build/Makefile.build:106: /tmp/tmp.ZWHbQftdN6/util/symbol.o] Error 1
    MKDIR   /tmp/tmp.ZWHbQftdN6/tests/workloads/
  make[6]: *** Waiting for unfinished jobs....

This was updated:

  -       symbols__fixup_end(&dso->symbols, false);
  -       symbols__fixup_duplicate(&dso->symbols);
  -       dso->adjust_symbols = 1;
  +       symbols__fixup_end(dso__symbols(dso), false);
  +       symbols__fixup_duplicate(dso__symbols(dso));
  +       dso__set_adjust_symbols(dso);

But not build tested with BUILD_NONDISTRO and libbfd devel files installed
(binutils-devel on fedora).

Add the missing argument:

   	symbols__fixup_end(dso__symbols(dso), false);
   	symbols__fixup_duplicate(dso__symbols(dso));
  -	dso__set_adjust_symbols(dso);
  +	dso__set_adjust_symbols(dso, true);

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Chengen Du <chengen.du@canonical.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Dima Kogan <dima@secretsauce.net>
Cc: Ilkka Koskinen <ilkka@os.amperecomputing.com>
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: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Li Dong <lidong@vivo.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paran Lee <p4ranlee@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Sun Haiyong <sunhaiyong@loongson.cn>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Yanteng Si <siyanteng@loongson.cn>
Cc: zhaimingbing <zhaimingbing@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20240504213803.218974-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-05-06 15:28:49 -03:00
Dima Kogan
c15ed44429 perf probe-event: Better error message for a too-long probe name
This is a common failure mode when probing userspace C++ code (where the
mangling adds significant length to the symbol names).

Prior to this patch, only a very generic error message is produced,
making the user guess at what the issue is.

Signed-off-by: Dima Kogan <dima@secretsauce.net>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240416045533.162692-3-dima@secretsauce.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-04-18 22:22:51 -03:00
Dima Kogan
a529bec023 perf probe-event: Un-hardcode sizeof(buf)
In several places we had

  char buf[64];
  ...
  snprintf(buf, 64, ...);

This patch changes it to

  char buf[64];
  ...
  snprintf(buf, sizeof(buf), ...);

so the "64" is only stated once.

Signed-off-by: Dima Kogan <dima@secretsauce.net>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20240416045533.162692-2-dima@secretsauce.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-04-18 22:22:51 -03:00
Arnaldo Carvalho de Melo
5810371519 perf probe: Add missing libgen.h header needed for using basename()
This prototype is obtained indirectly, by luck, from some other header
in probe-event.c in most systems, but recently exploded on alpine:edge:

   8    13.39 alpine:edge                   : FAIL gcc version 13.2.1 20240309 (Alpine 13.2.1_git20240309)
    util/probe-event.c: In function 'convert_exec_to_group':
    util/probe-event.c:225:16: error: implicit declaration of function 'basename' [-Werror=implicit-function-declaration]
      225 |         ptr1 = basename(exec_copy);
          |                ^~~~~~~~
    util/probe-event.c:225:14: error: assignment to 'char *' from 'int' makes pointer from integer without a cast [-Werror=int-conversion]
      225 |         ptr1 = basename(exec_copy);
          |              ^
    cc1: all warnings being treated as errors
    make[3]: *** [/git/perf-6.8.0/tools/build/Makefile.build:158: util] Error 2

Fix it by adding the libgen.h header where basename() is prototyped.

Fixes: fb7345bbf7 ("perf probe: Support basic dwarf-based operations on uprobe events")
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2024-03-21 13:54:40 -03:00
Ian Rogers
ec42d3d568 perf map: Fix map reference count issues
The find will get the map, ensure puts are done on all paths.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240229062048.558799-1-irogers@google.com
2024-02-29 18:06:00 -08:00
Ian Rogers
107ef66cb0 perf maps: Get map before returning in maps__find_by_name
Finding a map is done under a lock, returning the map without a
reference count means it can be removed without notice and causing
uses after free. Grab a reference count to the map within the lock
region and return this. Fix up locations that need a map__put
following this. Also fix some reference counted pointer comparisons.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: James Clark <james.clark@arm.com>
Cc: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Song Liu <song@kernel.org>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Artem Savkov <asavkov@redhat.com>
Cc: bpf@vger.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240210031746.4057262-4-irogers@google.com
2024-02-12 12:35:33 -08:00
Ian Rogers
300b53d5b8 perf probe-event: Use function to add missing maps lock
Switch kernel_get_module_map from loop macro maps__for_each_entry to
maps__for_each_map function that takes a callback. The function holds
the maps lock, which should be held during iteration.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <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 <mhiramat@kernel.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Namhyung Kim <namhyung@kernel.org>
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/20231207011722.1220634-8-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-12-18 21:35:07 -03:00
Arnaldo Carvalho de Melo
aeb50d3f2c perf probe: Make synthesize_perf_probe_point() private to probe-event.c
Not used in any other place, so just make it static.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/ZM0pjfOe6R4X%2Fcql@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-08-07 16:40:29 -03:00
Arnaldo Carvalho de Melo
a612bbf8b8 perf probe: Free string returned by synthesize_perf_probe_point() on failure in synthesize_perf_probe_command()
Building perf with EXTRA_CFLAGS="-fsanitize=address" a leak was detected
elsewhere and lead to an audit, where we found that
synthesize_perf_probe_command() may leak synthesize_perf_probe_point()
return on failure, fix it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/ZM0mzpQktHnhXJXr@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-08-07 16:40:29 -03:00
Arnaldo Carvalho de Melo
7bc0153c53 perf probe: Free string returned by synthesize_perf_probe_point() on failure to add a probe
Building perf with EXTRA_CFLAGS="-fsanitize=address" a leak is detect
when trying to add a probe to a non-existent function:

  # perf probe -x ~/bin/perf dso__neW
  Probe point 'dso__neW' not found.
    Error: Failed to add events.

  =================================================================
  ==296634==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 128 byte(s) in 1 object(s) allocated from:
      #0 0x7f67642ba097 in calloc (/lib64/libasan.so.8+0xba097)
      #1 0x7f67641a76f1 in allocate_cfi (/lib64/libdw.so.1+0x3f6f1)

  Direct leak of 65 byte(s) in 1 object(s) allocated from:
      #0 0x7f67642b95b5 in __interceptor_realloc.part.0 (/lib64/libasan.so.8+0xb95b5)
      #1 0x6cac75 in strbuf_grow util/strbuf.c:64
      #2 0x6ca934 in strbuf_init util/strbuf.c:25
      #3 0x9337d2 in synthesize_perf_probe_point util/probe-event.c:2018
      #4 0x92be51 in try_to_find_probe_trace_events util/probe-event.c:964
      #5 0x93d5c6 in convert_to_probe_trace_events util/probe-event.c:3512
      #6 0x93d6d5 in convert_perf_probe_events util/probe-event.c:3529
      #7 0x56f37f in perf_add_probe_events /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:354
      #8 0x572fbc in __cmd_probe /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:738
      #9 0x5730f2 in cmd_probe /var/home/acme/git/perf-tools-next/tools/perf/builtin-probe.c:766
      #10 0x635d81 in run_builtin /var/home/acme/git/perf-tools-next/tools/perf/perf.c:323
      #11 0x6362c1 in handle_internal_command /var/home/acme/git/perf-tools-next/tools/perf/perf.c:377
      #12 0x63667a in run_argv /var/home/acme/git/perf-tools-next/tools/perf/perf.c:421
      #13 0x636b8d in main /var/home/acme/git/perf-tools-next/tools/perf/perf.c:537
      #14 0x7f676302950f in __libc_start_call_main (/lib64/libc.so.6+0x2950f)

  SUMMARY: AddressSanitizer: 193 byte(s) leaked in 2 allocation(s).
  #

synthesize_perf_probe_point() returns a "detachec" strbuf, i.e. a
malloc'ed string that needs to be free'd.

An audit will be performed to find other such cases.

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/ZM0l1Oxamr4SVjfY@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-08-07 16:40:13 -03:00
Masami Hiramatsu
e8ca4f0f8c perf probe: Show correct error message about @symbol usage for uprobe
Since @symbol variable access is not supported by uprobe event, it must be
correctly warn user instead of kernel version update.

Committer testing:

With/without the patch:

  [root@quaco ~]# perf probe -x ~/bin/perf -L sigtrap_handler
  <sigtrap_handler@/home/acme/git/perf-tools-next/tools/perf/tests/sigtrap.c:0>
        0  sigtrap_handler(int signum __maybe_unused, siginfo_t *info, void *ucontext __maybe_unused)
        1  {
        2         if (!__atomic_fetch_add(&ctx.signal_count, 1, __ATOMIC_RELAXED))
        3                 ctx.first_siginfo = *info;
        4         __atomic_fetch_sub(&ctx.tids_want_signal, syscall(SYS_gettid), __ATOMIC_RELAXED);
        5  }

           static void *test_thread(void *arg)
           {

  [root@quaco ~]# perf probe -x ~/bin/perf sigtrap_handler:4 "ctx.signal_count"

Without the patch:

  [root@quaco ~]# perf probe -x ~/bin/perf sigtrap_handler:4 "ctx.signal_count"
  Failed to write event: Invalid argument
  Please upgrade your kernel to at least 3.14 to have access to feature @ctx
    Error: Failed to add events.
  [root@quaco ~]#

With the patch:

  [root@quaco ~]#
  Failed to write event: Invalid argument
  @ctx accesses a variable by symbol name, but that is not supported for user application probe.
    Error: Failed to add events.
  [root@quaco ~]#

Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Closes: https://lore.kernel.org/all/ZLWDEjvFjrrEJODp@kernel.org/
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lore.kernel.org/r/169055397023.67089.12693645664676964310.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-08-03 17:01:27 -03:00
Ian Rogers
d82257d7f6 perf symbol: Remove now unused symbol_conf.sort_by_name
Previously used to specify symbol_name_rb_node was in use.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Carsten Haitzler <carsten.haitzler@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Jason Wang <wangborong@cdjrlc.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20230623054520.4118442-4-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2023-06-23 21:48:49 -07:00
Ian Rogers
259dce914e perf symbol: Remove symbol_name_rb_node
Most perf commands want to sort symbols by name and this is done via
an invasive rbtree that on 64-bit systems costs 24 bytes. Sorting the
symbols in a DSO by name is optional and not done by default, however,
if sorting is requested the 24 bytes is allocated for every
symbol.

This change removes the rbtree and uses a sorted array of symbol
pointers instead (costing 8 bytes per symbol). As the array is created
on demand then there are further memory savings. The complexity of
sorting the array and using the rbtree are the same.

To support going to the next symbol, the index of the current symbol
needs to be passed around as a pair with the current symbol. This
requires some API changes.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Carsten Haitzler <carsten.haitzler@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Jason Wang <wangborong@cdjrlc.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20230623054520.4118442-3-irogers@google.com
[ minimize change in symbols__sort_by_name() ]
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2023-06-23 21:47:20 -07:00
Ian Rogers
ce5b293405 perf dso: Sort symbols under lock
Determine if symbols are sorted, set the sorted flag and sort under
the dso lock. Done in the interest of thread safety.

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Carsten Haitzler <carsten.haitzler@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Jason Wang <wangborong@cdjrlc.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20230623054520.4118442-2-irogers@google.com
[ handle the similar code in util/probe-event.c ]
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2023-06-23 21:44:48 -07:00
Ian Rogers
2a6e5e8a2a perf map: Add accessors for ->pgoff and ->reloc
Later changes will add reference count checking for 'struct map'. Add
accessors so that the reference count check is only necessary in one
place.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miaoqian Lin <linmq006@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: https://lore.kernel.org/r/20230404205954.2245628-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-06 22:12:40 -03:00
Ian Rogers
78a1f7cd90 perf map: Add helper for ->map_ip() and ->unmap_ip()
Later changes will add reference count checking for struct map, add a
helper function to invoke the map_ip and unmap_ip function pointers. The
helper allows the reference count check to be in fewer places.

Committer notes:

Add missing conversions to:

  tools/perf/util/map.c
  tools/perf/util/cs-etm.c
  tools/perf/util/annotate.c
  tools/perf/arch/powerpc/util/sym-handling.c
  tools/perf/arch/s390/annotate/instructions.c

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miaoqian Lin <linmq006@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: https://lore.kernel.org/r/20230404205954.2245628-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-06 22:10:17 -03:00
Ian Rogers
e5116f46d4 perf map: Add accessor for start and end
Later changes will add reference count checking for struct map, start
and end are frequently accessed variables. Add an accessor so that the
reference count check is only necessary in one place.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miaoqian Lin <linmq006@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: https://lore.kernel.org/r/20230320212248.1175731-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-04 16:54:11 -03:00
Ian Rogers
63df0e4bc3 perf map: Add accessor for dso
Later changes will add reference count checking for struct map, with
dso being the most frequently accessed variable. Add an accessor so
that the reference count check is only necessary in one place.

Additional changes:
 - add a dso variable to avoid repeated map__dso calls.
 - in builtin-mem.c dump_raw_samples, code only partially tested for
   dso == NULL. Make the possibility of NULL consistent.
 - in thread.c thread__memcpy fix use of spaces and use tabs.

Committer notes:

Did missing conversions on these files:

   tools/perf/arch/powerpc/util/skip-callchain-idx.c
   tools/perf/arch/powerpc/util/sym-handling.c
   tools/perf/ui/browsers/hists.c
   tools/perf/ui/gtk/annotate.c
   tools/perf/util/cs-etm.c
   tools/perf/util/thread.c
   tools/perf/util/unwind-libunwind-local.c
   tools/perf/util/unwind-libunwind.c

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miaoqian Lin <linmq006@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: https://lore.kernel.org/r/20230320212248.1175731-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-04 16:41:57 -03:00
Ian Rogers
ff583dc43d perf maps: Remove rb_node from struct map
struct map is reference counted, having it also be a node in an
red-black tree complicates the reference counting. Switch to having a
map_rb_node which is a red-block tree node but points at the reference
counted struct map. This reference is responsible for a single reference
count.

Committer notes:

Fixed up tools/perf/util/unwind-libunwind-local.c to use map_rb_node as
well.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miaoqian Lin <linmq006@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: https://lore.kernel.org/r/20230320212248.1175731-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-04-04 14:06:27 -03:00
Athira Rajeev
67ef66bad4 perf probe: Update the exit error codes in function try_to_find_probe_trace_event
try_to_find_probe_trace_events() uses return error code as ENOENT in two
places.

First place is after open_debuginfo() when opening debuginfo fails and
secondly, after when not finding the probe point.

This function is invoked during BPF load and there are other exit points
in this code path which returns ENOENT. This makes it difficult to
understand the exact reason for exit.

Patches changes the exit code from ENOENT to:

- ENODATA when it fails to find debuginfo

- ENODEV when it fails to find probe point

Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Disha Goel <disgoel@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nageswara R Sastry <rnsastry@linux.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Link: https://lore.kernel.org/r/20230105121742.92249-1-atrajeev@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-02-06 15:00:05 -03:00
Ian Rogers
e54dea69cd perf dso: Hold lock when accessing nsinfo
There may be threads racing to update dso->nsinfo:

  https://lore.kernel.org/linux-perf-users/CAP-5=fWZH20L4kv-BwVtGLwR=Em3AOOT+Q4QGivvQuYn5AsPRg@mail.gmail.com/

Holding the dso->lock avoids use-after-free, memory leaks and other such
bugs. Apply the fix in:

  https://lore.kernel.org/linux-perf-users/20211118193714.2293728-1-irogers@google.com/

of there being a missing nsinfo__put now that the accesses are data race
free. Fixes test "Lookup mmap thread" when compiled with address
sanitizer.

Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexandre Truong <alexandre.truong@arm.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andres Freund <andres@anarazel.de>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: André Almeida <andrealmeid@igalia.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Colin Ian King <colin.king@intel.com>
Cc: Dario Petrillo <dario.pk1@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Dave Marchevsky <davemarchevsky@fb.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Fangrui Song <maskray@google.com>
Cc: Hewenliang <hewenliang4@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jason Wang <wangborong@cdjrlc.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kim Phillips <kim.phillips@amd.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Liška <mliska@suse.cz>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Pavithra Gurushankar <gpavithrasha@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Remi Bernon <rbernon@codeweavers.com>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Tom Rix <trix@redhat.com>
Cc: Weiguo Li <liwg06@foxmail.com>
Cc: Wenyu Liu <liuwenyu7@huawei.com>
Cc: William Cohen <wcohen@redhat.com>
Cc: Zechuan Chen <chenzechuan1@huawei.com>
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Cc: yaowenbin <yaowenbin1@huawei.com>
Link: https://lore.kernel.org/r/20220826164242.43412-15-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-10-04 08:55:20 -03:00
Christophe JAILLET
4bf6dcaa93 perf probe: Fix an error handling path in 'parse_perf_probe_command()'
If a memory allocation fail, we should branch to the error handling path
in order to free some resources allocated a few lines above.

Fixes: 15354d5469 ("perf probe: Generate event name with line number")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: kernel-janitors@vger.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/b71bcb01fa0c7b9778647235c3ab490f699ba278.1659797452.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-08-10 10:44:02 -03:00
Jason Wang
c69d33ebfa perf probe: Fix duplicated 'the' in comment
The double `the' is duplicated in the comment, remove one.

Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Zechuan Chen <chenzechuan1@huawei.com>
Link: http://lore.kernel.org/lkml/20220716043957.42829-1-wangborong@cdjrlc.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-07-20 11:09:11 -03:00
Ian Rogers
1a97cee604 perf maps: Use a pointer for kmaps
struct maps is reference counted, using a pointer is more idiomatic.

Committer notes:

Delay:

   maps = machine__kernel_maps(&vmlinux);

To after:

  machine__init(&vmlinux, "", HOST_KERNEL_ID);

To avoid this on f34:

  In file included from /var/home/acme/git/perf/tools/perf/util/build-id.h:10,
                   from /var/home/acme/git/perf/tools/perf/util/dso.h:13,
                   from tests/vmlinux-kallsyms.c:8:
  In function ‘machine__kernel_maps’,
      inlined from ‘test__vmlinux_matches_kallsyms’ at tests/vmlinux-kallsyms.c:122:22:
  /var/home/acme/git/perf/tools/perf/util/machine.h:86:23: error: ‘vmlinux.kmaps’ is used uninitialized [-Werror=uninitialized]
     86 |         return machine->kmaps;
        |                ~~~~~~~^~~~~~~
  tests/vmlinux-kallsyms.c: In function ‘test__vmlinux_matches_kallsyms’:
  tests/vmlinux-kallsyms.c:121:34: note: ‘vmlinux’ declared here
    121 |         struct machine kallsyms, vmlinux;
        |                                  ^~~~~~~
  cc1: all warnings being treated as errors

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: André Almeida <andrealmeid@collabora.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Hao Luo <haoluo@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Miaoqian Lin <linmq006@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Yury Norov <yury.norov@gmail.com>
Link: http://lore.kernel.org/lkml/20220211103415.2737789-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-02-14 16:47:13 -03:00
Zechuan Chen
4624f19932 perf probe: Fix ppc64 'perf probe add events failed' case
Because of commit bf794bf52a ("powerpc/kprobes: Fix kallsyms
lookup across powerpc ABIv1 and ABIv2"), in ppc64 ABIv1, our perf
command eliminates the need to use the prefix "." at the symbol name.

But when the command "perf probe -a schedule" is executed on ppc64
ABIv1, it obtains two symbol address information through /proc/kallsyms,
for example:

  cat /proc/kallsyms | grep -w schedule
  c000000000657020 T .schedule
  c000000000d4fdb8 D schedule

The symbol "D schedule" is not a function symbol, and perf will print:
"p:probe/schedule _text+13958584"Failed to write event: Invalid argument

Therefore, when searching symbols from map and adding probe point for
them, a symbol type check is added. If the type of symbol is not a
function, skip it.

Fixes: bf794bf52a ("powerpc/kprobes: Fix kallsyms lookup across powerpc ABIv1 and ABIv2")
Signed-off-by: Zechuan Chen <chenzechuan1@huawei.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jianlin Lv <Jianlin.Lv@arm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Link: https://lore.kernel.org/r/20211228111338.218602-1-chenzechuan1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-18 09:24:58 -03:00
Yang Jihong
22a665513b perf probe: Fix add event failure when running 32-bit perf in a 64-bit kernel
The "address" member of "struct probe_trace_point" uses long data type.
If kernel is 64-bit and perf program is 32-bit, size of "address"
variable is 32 bits.

As a result, upper 32 bits of address read from kernel are truncated, an
error occurs during address comparison in kprobe_warn_out_range().

Before:

  # perf probe -a schedule
  schedule is out of .text, skip it.
    Error: Failed to add events.

Solution:
  Change data type of "address" variable to u64 and change corresponding
address printing and value assignment.

After:

  # perf.new.new probe -a schedule
  Added new event:
    probe:schedule       (on schedule)

  You can now use it in all perf tools, such as:

          perf record -e probe:schedule -aR sleep 1

  # perf probe -l
    probe:schedule       (on schedule@kernel/sched/core.c)
  # perf record -e probe:schedule -aR sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.156 MB perf.data (1366 samples) ]
  # perf report --stdio
  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 1K of event 'probe:schedule'
  # Event count (approx.): 1366
  #
  # Overhead  Command          Shared Object      Symbol
  # ........  ...............  .................  ............
  #
       6.22%  migration/0      [kernel.kallsyms]  [k] schedule
       6.22%  migration/1      [kernel.kallsyms]  [k] schedule
       6.22%  migration/2      [kernel.kallsyms]  [k] schedule
       6.22%  migration/3      [kernel.kallsyms]  [k] schedule
       6.15%  migration/10     [kernel.kallsyms]  [k] schedule
       6.15%  migration/11     [kernel.kallsyms]  [k] schedule
       6.15%  migration/12     [kernel.kallsyms]  [k] schedule
       6.15%  migration/13     [kernel.kallsyms]  [k] schedule
       6.15%  migration/14     [kernel.kallsyms]  [k] schedule
       6.15%  migration/15     [kernel.kallsyms]  [k] schedule
       6.15%  migration/4      [kernel.kallsyms]  [k] schedule
       6.15%  migration/5      [kernel.kallsyms]  [k] schedule
       6.15%  migration/6      [kernel.kallsyms]  [k] schedule
       6.15%  migration/7      [kernel.kallsyms]  [k] schedule
       6.15%  migration/8      [kernel.kallsyms]  [k] schedule
       6.15%  migration/9      [kernel.kallsyms]  [k] schedule
       0.22%  rcu_sched        [kernel.kallsyms]  [k] schedule
  ...
  #
  # (Cannot load tips.txt file, please install perf!)
  #

Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jianlin Lv <jianlin.lv@arm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Li Huafei <lihuafei1@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lore.kernel.org/lkml/20210715063723.11926-1-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-07-18 09:31:15 -03:00
Riccardo Mancini
dedeb4be20 perf probe: Fix dso->nsinfo refcounting
ASan reports a memory leak of nsinfo during the execution of:

 # perf test "31: Lookup mmap thread".

The leak is caused by a refcounted variable being replaced without
dropping the refcount.

This patch makes sure that the refcnt of nsinfo is decreased whenever
a refcounted variable is replaced with a new value.

Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>
Fixes: 544abd44c7 ("perf probe: Allow placing uprobes in alternate namespaces.")
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/55223bc8821b34ccb01f92ef1401c02b6a32e61f.1626343282.git.rickyman7@gmail.com
[ Split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-07-15 17:25:28 -03:00
Masami Hiramatsu
45237f9898 perf probe: Add --bootconfig to output definition in bootconfig format
Now the boot-time tracing supports kprobes events and that must be
written in bootconfig file in the following format.

  ftrace.event.kprobes.<EVENT_NAME>.probes = <PROBE-DEF>

'perf probe' already supports --definition (-D) action to show probe
definitions, but the format is for tracefs:

  [p|r][:EVENT_NAME] <PROBE-DEF>

This patch adds the --bootconfig option for -D action so that it outputs
the probe definitions in bootconfig format. E.g.

  $ perf probe --bootconfig -D "path_lookupat:7 err:s32 s:string"
  ftrace.event.kprobes.path_lookupat_L7.probe = 'path_lookupat.isra.0+309 err_s32=%ax:s32 s_string=+0(%r13):string'

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/162282412351.452340.14871995440005640114.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-06-18 13:50:05 -03:00
Masami Hiramatsu
d26ea48144 perf probe: Cleanup synthesize_probe_trace_command()
Cleanup synthesize_probe_trace_command() to simplify the code path.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/162282411361.452340.16886399333622147122.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-06-18 13:50:05 -03:00
Masami Hiramatsu
f338de2219 perf probe: Support probes on init functions for offline kernel
'perf probe' internally checks the probe target is in the text area in
post-process (after analyzing debuginfo). But it fails if the probe
target is in the "inittext".

This is a good limitation for the online kernel because such functions
have gone after booting. However, for using it for boot-time tracing,
user may want to put a probe on init functions.

This skips the post checking process if the target is offline kenrel so
that user can get the probe definition on the init functions.

Without this patch:

  $ perf probe -k ./build-x86_64/vmlinux -D do_mount_root:10
  Probe point 'do_mount_root:10' not found.
    Error: Failed to add events.

With this patch:

  $ perf probe -k ./build-x86_64/vmlinux -D do_mount_root:10
  p:probe/do_mount_root_L10 mount_block_root+300

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/162282410293.452340.13347006295826431632.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-06-18 13:50:05 -03:00
Masami Hiramatsu
f4f1c42953 perf probe: Report possible permission error for map__load() failure
Report possible permission error including kptr_restrict setting
for map__load() failure. This can happen when non-superuser runs
perf probe.

With this patch, perf probe shows the following message.

 $ perf probe vfs_read
 Failed to load symbols from /proc/kallsyms
 Please ensure you can read the /proc/kallsyms symbol addresses.
 If the /proc/sys/kernel/kptr_restrict is '2', you can not read
 kernel symbol address even if you are a superuser. Please change
 it to '1'. If kptr_restrict is '1', the superuser can read the
 symbol addresses.
 In that case, please run this command again with sudo.
   Error: Failed to add events.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/162282065877.448336.10047912688119745151.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-06-04 15:43:37 -03:00
Ravi Bangoria
41ca1d1e88 perf probe: Provide more detail with relocation warning
When run as normal user with default sysctl kernel.kptr_restrict=0
and kernel.perf_event_paranoid=2, perf probe fails with:

  $ ./perf probe move_page_tables
  Relocated base symbol is not found!

The warning message is not much informative. The reason perf fails
is because /proc/kallsyms is restricted by perf_event_paranoid=2
for normal user and thus perf fails to read relocated address of
the base symbol.

Tweaking kptr_restrict and perf_event_paranoid can change the
behavior of perf probe. Also, running as root or privileged user
works too. Add these details in the warning message.

Plus, kmap->ref_reloc_sym might not be always set even if
host_machine is initialized. Above is the example of the same.
Remove that comment.

Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20210525043744.193297-1-ravi.bangoria@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-05-27 13:55:28 -03:00
Ingo Molnar
4d39c89f0b perf tools: Fix various typos in comments
Fix ~124 single-word typos and a few spelling errors in the perf tooling code,
accumulated over the years.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210321113734.GA248990@gmail.com
Link: http://lore.kernel.org/lkml/20210323160915.GA61903@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-03-23 17:13:43 -03:00
Arnaldo Carvalho de Melo
c1bd8a2b9f Merge branch 'perf/urgent' into perf/core
To get some fixes that didn't made into 5.11.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-02-16 11:52:16 -03:00
Jianlin Lv
105f75ebf9 perf probe: Fix kretprobe issue caused by GCC bug
Perf failed to add a kretprobe event with debuginfo of vmlinux which is
compiled by gcc with -fpatchable-function-entry option enabled.  The
same issue with kernel module.

Issue:

  # perf probe  -v 'kernel_clone%return $retval'
  ......
  Writing event: r:probe/kernel_clone__return _text+599624 $retval
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)

  # cat /sys/kernel/debug/tracing/error_log
  [156.75] trace_kprobe: error: Retprobe address must be an function entry
  Command: r:probe/kernel_clone__return _text+599624 $retval
                                        ^

  # llvm-dwarfdump  vmlinux |grep  -A 10  -w 0x00df2c2b
  0x00df2c2b:   DW_TAG_subprogram
                DW_AT_external  (true)
                DW_AT_name      ("kernel_clone")
                DW_AT_decl_file ("/home/code/linux-next/kernel/fork.c")
                DW_AT_decl_line (2423)
                DW_AT_decl_column       (0x07)
                DW_AT_prototyped        (true)
                DW_AT_type      (0x00dcd492 "pid_t")
                DW_AT_low_pc    (0xffff800010092648)
                DW_AT_high_pc   (0xffff800010092b9c)
                DW_AT_frame_base        (DW_OP_call_frame_cfa)

  # cat /proc/kallsyms |grep kernel_clone
  ffff800010092640 T kernel_clone
  # readelf -s vmlinux |grep -i kernel_clone
  183173: ffff800010092640  1372 FUNC    GLOBAL DEFAULT    2 kernel_clone

  # objdump -d vmlinux |grep -A 10  -w \<kernel_clone\>:
  ffff800010092640 <kernel_clone>:
  ffff800010092640:       d503201f        nop
  ffff800010092644:       d503201f        nop
  ffff800010092648:       d503233f        paciasp
  ffff80001009264c:       a9b87bfd        stp     x29, x30, [sp, #-128]!
  ffff800010092650:       910003fd        mov     x29, sp
  ffff800010092654:       a90153f3        stp     x19, x20, [sp, #16]

The entry address of kernel_clone converted by debuginfo is _text+599624
(0x92648), which is consistent with the value of DW_AT_low_pc attribute.
But the symbolic address of kernel_clone from /proc/kallsyms is
ffff800010092640.

This issue is found on arm64, -fpatchable-function-entry=2 is enabled when
CONFIG_DYNAMIC_FTRACE_WITH_REGS=y;
Just as objdump displayed the assembler contents of kernel_clone,
GCC generate 2 NOPs  at the beginning of each function.

kprobe_on_func_entry detects that (_text+599624) is not the entry address
of the function, which leads to the failure of adding kretprobe event.

  kprobe_on_func_entry
  ->_kprobe_addr
  ->kallsyms_lookup_size_offset
  ->arch_kprobe_on_func_entry		// FALSE

The cause of the issue is that the first instruction in the compile unit
indicated by DW_AT_low_pc does not include NOPs.
This issue exists in all gcc versions that support
-fpatchable-function-entry option.

I have reported it to the GCC community:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98776

Currently arm64 and PA-RISC may enable fpatchable-function-entry option.
The kernel compiled with clang does not have this issue.

FIX:

This GCC issue only cause the registration failure of the kretprobe event
which doesn't need debuginfo. So, stop using debuginfo for retprobe.
map will be used to query the probe function address.

Signed-off-by: Jianlin Lv <Jianlin.Lv@arm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: clang-built-linux@googlegroups.com
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20210210062646.2377995-1-Jianlin.Lv@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-02-12 18:34:25 -03:00
Jin Yao
94253393df perf intlist: Change 'struct intlist' int member to 'unsigned long'
This is to let intlist support addresses as its payload.

One potential problem is it can't support negative number. But so far,
there is no such kind of use case.

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210207080935.31784-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-02-08 17:02:00 -03:00
Jiri Olsa
bf5411695a perf tools: Pass build_id object to build_id__sprintf()
Passing build_id object to build_id__sprintf function, so it can operate
with the proper size of build id.

This will create proper md5 build id readable names,
like following:

  a50e350e97c43b4708d09bcd85ebfff7

instead of:

  a50e350e97c43b4708d09bcd85ebfff700000000

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20201013192441.1299447-5-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-10-14 08:46:22 -03:00
Jiri Olsa
0aba7f036a perf tools: Use build_id object in dso
Replace build_id byte array with struct build_id object and all the code
that references it.

The objective is to carry size together with build id array, so it's
better to keep both together.

This is preparatory change for following patches, and there's no
functional change.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20201013192441.1299447-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-10-14 08:44:47 -03:00
Masami Hiramatsu
7cd5738d0d perf probe: Fall back to debuginfod query if debuginfo and source not found locally
Since 'perf probe' heavily depends on debuginfo, debuginfod gives us
many benefits on the 'perf probe' command on remote machine.

Especially, this will be helpful for the embedded devices which will not
have enough storage, or boot with a cross-build kernel whose source code
is in the host machine.

This will work as similar to commit c7a14fdcb3 ("perf build-ids:
Fall back to debuginfod query if debuginfo not found")

Tested with:

  (host) $ cd PATH/TO/KBUILD/DIR/
  (host) $ debuginfod -F .
  ...

  (remote) # perf probe -L vfs_read
  Failed to find the path for the kernel: No such file or directory
    Error: Failed to show lines.

  (remote) # export DEBUGINFOD_URLS="http://$HOST_IP:8002/"
  (remote) # perf probe -L vfs_read
  <vfs_read@...>
        0  ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos)
           {
        2         ssize_t ret;

                  if (!(file->f_mode & FMODE_READ))
                          return -EBADF;
        6         if (!(file->f_mode & FMODE_CAN_READ))
                          return -EINVAL;
        8         if (unlikely(!access_ok(buf, count)))
                          return -EFAULT;

       11         ret = rw_verify_area(READ, file, pos, count);
       12         if (ret)
                          return ret;
                  if (count > MAX_RW_COUNT)
  ...

  (remote) # perf probe -a "vfs_read count"
  Added new event:
    probe:vfs_read       (on vfs_read with count)

  (remote) # perf probe -l
    probe:vfs_read       (on vfs_read@ksrc/linux/fs/read_write.c with count)

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Frank Ch. Eigler <fche@redhat.com>
Cc: Aaron Merey <amerey@redhat.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Link: http://lore.kernel.org/lkml/160041610083.912668.13659563860278615846.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-18 09:20:47 -03:00
Masami Hiramatsu
ac7a75d1fb perf probe: Fix to adjust symbol address with correct reloc_sym address
'perf probe' uses ref_reloc_sym to adjust symbol offset address from
debuginfo address or ref_reloc_sym based address, but that is misusing
reloc_sym->addr and reloc_sym->unrelocated_addr.  If map is not
relocated (map->reloc == 0), we can use reloc_sym->addr as unrelocated
address instead of reloc_sym->unrelocated_addr.

This usually does not happen. If we have a non-stripped ELF binary, we
will use it for map and debuginfo, if not, we use only kallsyms without
debuginfo. Thus, the map is always relocated (ELF and DWARF binary) or
not relocated (kallsyms).

However, if we allow the combination of debuginfo and kallsyms based map
(like using debuginfod), we have to check the map->reloc and choose the
collect address of reloc_sym.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Frank Ch. Eigler <fche@redhat.com>
Cc: Aaron Merey <amerey@redhat.com>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Link: http://lore.kernel.org/lkml/160041609047.912668.14314639291419159274.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-09-18 09:19:03 -03:00
Masami Hiramatsu
3de2bf9dfb perf probe: Warn if the target function is a GNU indirect function
Warn if the probe target function is a GNU indirect function (GNU_IFUNC)
because it may not be what the user wants to probe.

The GNU indirect function ( https://sourceware.org/glibc/wiki/GNU_IFUNC )
is the dynamic symbol solved at runtime. An IFUNC function is a selector
which is invoked from the ELF loader, but the symbol address of the
function which will be modified by the IFUNC is the same as the IFUNC in
the symbol table. This can confuse users trying to probe such functions.

For example, memcpy is an IFUNC.

  probe_libc:memcpy    (on __new_memcpy_ifunc@x86_64/multiarch/memcpy.c in /usr/lib64/libc-2.30.so)

the probe is put on an IFUNC.

  perf  1742 [000] 26201.715632: probe_libc:memcpy: (7fdaa53824c0)
              7fdaa53824c0 __new_memcpy_ifunc+0x0 (inlined)
              7fdaa5d4a980 elf_machine_rela+0x6c0 (inlined)
              7fdaa5d4a980 elf_dynamic_do_Rela+0x6c0 (inlined)
              7fdaa5d4a980 _dl_relocate_object+0x6c0 (/usr/lib64/ld-2.30.so)
              7fdaa5d42155 dl_main+0x1cc5 (/usr/lib64/ld-2.30.so)
              7fdaa5d5831a _dl_sysdep_start+0x54a (/usr/lib64/ld-2.30.so)
              7fdaa5d3ffeb _dl_start_final+0x25b (inlined)
              7fdaa5d3ffeb _dl_start+0x25b (/usr/lib64/ld-2.30.so)
              7fdaa5d3f117 .annobin_rtld.c+0x7 (inlined)

And the event is invoked from the ELF loader instead of the target
program's main code.

Moreover, at this moment, we can not probe on the function which will
be selected by the IFUNC, because it is determined at runtime. But
uprobe will be prepared before running the target binary.

Thus, I decided to warn user when 'perf probe' detects that the probe
point is on an GNU IFUNC symbol. Someone who wants to probe an IFUNC
symbol to debug the IFUNC function can ignore this warning.

Committer notes:

I.e., this warning will be emitted if the probe point is an IFUNC:

  "Warning: The probe function (%s) is a GNU indirect function.\n"
  "Consider identifying the final function used at run time and set the probe directly on that.\n"

Complete set of steps:

  # readelf -sW /lib64/libc-2.29.so  | grep IFUNC | tail
   22196: 0000000000109a80   183 IFUNC   GLOBAL DEFAULT   14 __memcpy_chk
   22214: 00000000000b7d90   191 IFUNC   GLOBAL DEFAULT   14 __gettimeofday
   22336: 000000000008b690    60 IFUNC   GLOBAL DEFAULT   14 memchr
   22350: 000000000008b9b0    89 IFUNC   GLOBAL DEFAULT   14 __stpcpy
   22420: 000000000008bb10    76 IFUNC   GLOBAL DEFAULT   14 __strcasecmp_l
   22582: 000000000008a970    60 IFUNC   GLOBAL DEFAULT   14 strlen
   22585: 00000000000a54d0    92 IFUNC   WEAK   DEFAULT   14 wmemset
   22600: 000000000010b030    92 IFUNC   GLOBAL DEFAULT   14 __wmemset_chk
   22618: 000000000008b8a0   183 IFUNC   GLOBAL DEFAULT   14 __mempcpy
   22675: 000000000008ba70    76 IFUNC   WEAK   DEFAULT   14 strcasecmp
  #
  # perf probe -x /lib64/libc-2.29.so strlen
  Warning: The probe function (strlen) is a GNU indirect function.
  Consider identifying the final function used at run time and set the probe directly on that.
  Added new event:
    probe_libc:strlen    (on strlen in /usr/lib64/libc-2.29.so)

  You can now use it in all perf tools, such as:

  	perf record -e probe_libc:strlen -aR sleep 1

  #

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lore.kernel.org/lkml/159438669349.62703.5978345670436126948.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-07-17 09:09:47 -03:00
Masami Hiramatsu
26bbf45fc8 perf probe: Avoid setting probes on the same address for the same event
There is a case that several same-name symbols points to the same
address.  In that case, 'perf probe' returns an error.

E.g.

  # perf probe -x /lib64/libc-2.30.so -v -a "memcpy arg1=%di"
  probe-definition(0): memcpy arg1=%di
  symbol:memcpy file:(null) line:0 offset:0 return:0 lazy:(null)
  parsing arg: arg1=%di into name:arg1 %di
  1 arguments
  symbol:setjmp file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:longjmp file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:longjmp_target file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:lll_lock_wait_private file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_arena_max file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_arena_test file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_tunable_tcache_max_bytes file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_tunable_tcache_count file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_tunable_tcache_unsorted_limit file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_trim_threshold file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_top_pad file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_mmap_threshold file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_mmap_max file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_perturb file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_mxfast file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_heap_new file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_arena_reuse_free_list file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_arena_reuse file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_arena_reuse_wait file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_arena_new file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_arena_retry file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_sbrk_less file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_heap_free file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_heap_less file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_tcache_double_free file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_heap_more file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_sbrk_more file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_malloc_retry file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_memalign_retry file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt_free_dyn_thresholds file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_realloc_retry file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_calloc_retry file:(null) line:0 offset:0 return:0 lazy:(null)
  symbol:memory_mallopt file:(null) line:0 offset:0 return:0 lazy:(null)
  Open Debuginfo file: /usr/lib/debug/usr/lib64/libc-2.30.so.debug
  Try to find probe point from debuginfo.
  Opening /sys/kernel/debug/tracing//README write=0
  Failed to find the location of the '%di' variable at this address.
   Perhaps it has been optimized out.
   Use -V with the --range option to show '%di' location range.
  An error occurred in debuginfo analysis (-2).
  Trying to use symbols.
  Opening /sys/kernel/debug/tracing//uprobe_events write=1
  Writing event: p:probe_libc/memcpy /usr/lib64/libc-2.30.so:0x914c0 arg1=%di
  Writing event: p:probe_libc/memcpy /usr/lib64/libc-2.30.so:0x914c0 arg1=%di
  Failed to write event: File exists
    Error: Failed to add events. Reason: File exists (Code: -17)

You can see that perf tried to write completely the same probe
definition twice, which caused an error.

To fix this issue, check the symbol list and drop duplicated symbols
(which has the same symbol name and address) from it.

With this patch:

  # perf probe -x /lib64/libc-2.30.so -a "memcpy arg1=%di"
  Failed to find the location of the '%di' variable at this address.
   Perhaps it has been optimized out.
   Use -V with the --range option to show '%di' location range.
  Added new events:
    probe_libc:memcpy    (on memcpy in /usr/lib64/libc-2.30.so with arg1=%di)
    probe_libc:memcpy    (on memcpy in /usr/lib64/libc-2.30.so with arg1=%di)

  You can now use it in all perf tools, such as:

  	perf record -e probe_libc:memcpy -aR sleep 1

Committer notes:

Fix this build error on 32-bit arches by using PRIx64 for symbol->start,
that is an u64:

  In file included from util/probe-event.c:27:
  util/probe-event.c: In function 'find_probe_trace_events_from_map':
  util/probe-event.c:2978:14: error: format '%lx' expects argument of type 'long unsigned int', but argument 5 has type 'u64' {aka 'long long unsigned int'} [-Werror=format=]
       pr_debug("Found duplicated symbol %s @ %lx\n",
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  util/debug.h:17:21: note: in definition of macro 'pr_fmt'
   #define pr_fmt(fmt) fmt
                       ^~~
  util/probe-event.c:2978:5: note: in expansion of macro 'pr_debug'
       pr_debug("Found duplicated symbol %s @ %lx\n",
       ^~~~~~~~

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: http://lore.kernel.org/lkml/159438666401.62703.15196394835032087840.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-07-17 09:07:34 -03:00
Sumanth Korikkar
9256c3031e perf probe: Fix user attribute access in kprobes
Issue:

  # perf probe -a 'do_sched_setscheduler pid policy param->sched_priority@user'

did not work before.

Fix:

Make:

  # perf probe -a 'do_sched_setscheduler pid policy param->sched_priority@user'

output equivalent to ftrace:

  # echo 'p:probe/do_sched_setscheduler _text+517384 pid=%r2:s32 policy=%r3:s32 sched_priority=+u0(%r4):s32' > /sys/kernel/debug/tracing/kprobe_events

Other:

1. Right now, __match_glob() does not handle [u]<offset>. For now, use
  *u]<offset>.

2. @user attribute was introduced in commit 1e032f7cfa ("perf-probe:
   Add user memory access attribute support")

Test:
1. perf probe -a 'do_sched_setscheduler  pid policy
   param->sched_priority@user'

2 ./perf script
   sched 305669 [000] 1614458.838675: perf_bpf_probe:func: (2904e508)
   pid=261614 policy=2 sched_priority=1

3. cat /sys/kernel/debug/tracing/trace
   <...>-309956 [006] .... 1616098.093957: 0: prio: 1

Committer testing:

Before:

  # perf probe -a 'do_sched_setscheduler pid policy param->sched_priority@user'
  param(type:sched_param) has no member sched_priority@user.
    Error: Failed to add events.
  # pahole sched_param
  struct sched_param {
  	int                        sched_priority;       /*     0     4 */

  	/* size: 4, cachelines: 1, members: 1 */
  	/* last cacheline: 4 bytes */
  };
  #

After:

  # perf probe -a 'do_sched_setscheduler pid policy param->sched_priority@user'
  Added new event:
    probe:do_sched_setscheduler (on do_sched_setscheduler with pid policy sched_priority=param->sched_priority)

  You can now use it in all perf tools, such as:

  	perf record -e probe:do_sched_setscheduler -aR sleep 1

  # cat /sys/kernel/debug/tracing/kprobe_events
  p:probe/do_sched_setscheduler _text+1113792 pid=%di:s32 policy=%si:s32 sched_priority=+u0(%dx):s32
  #

Fixes: 1e032f7cfa ("perf-probe: Add user memory access attribute support")
Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Reviewed-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: bpf@vger.kernel.org
LPU-Reference: 20200609081019.60234-2-sumanthk@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-06-09 12:40:04 -03:00
Masami Hiramatsu
2ae5d0d7d8 perf probe: Check address correctness by map instead of _etext
Since commit 03db8b583d ("perf tools: Fix
maps__find_symbol_by_name()") introduced map address range check in
maps__find_symbol_by_name(), we can not get "_etext" from kernel map
because _etext is placed on the edge of the kernel .text section (=
kernel map in perf.)

To fix this issue, this checks the address correctness by map address
range information (map->start and map->end) instead of using _etext
address.

This can cause an error if the target inlined function is embedded in
both __init function and normal function.

For exaample, request_resource() is a normal function but also embedded
in __init reserve_setup(). In this case, the probe point in
reserve_setup() must be skipped.

However, without this fix, it failes to setup all probe points:

  # ./perf probe -v request_resource
  probe-definition(0): request_resource
  symbol:request_resource file:(null) line:0 offset:0 return:0 lazy:(null)
  0 arguments
  Looking at the vmlinux_path (8 entries long)
  Using /usr/lib/debug/lib/modules/5.5.17-200.fc31.x86_64/vmlinux for symbols
  Open Debuginfo file: /usr/lib/debug/lib/modules/5.5.17-200.fc31.x86_64/vmlinux
  Try to find probe point from debuginfo.
  Matched function: request_resource [15e29ad]
  found inline addr: 0xffffffff82fbf892
  Probe point found: reserve_setup+204
  found inline addr: 0xffffffff810e9790
  Probe point found: request_resource+0
  Found 2 probe_trace_events.
  Opening /sys/kernel/debug/tracing//kprobe_events write=1
  Opening /sys/kernel/debug/tracing//README write=0
  Writing event: p:probe/request_resource _text+33290386
  Failed to write event: Invalid argument
    Error: Failed to add events. Reason: Invalid argument (Code: -22)
  #

With this fix,

  # ./perf probe request_resource
  reserve_setup is out of .text, skip it.
  Added new events:
    (null):(null)        (on request_resource)
    probe:request_resource (on request_resource)

  You can now use it in all perf tools, such as:

  	perf record -e probe:request_resource -aR sleep 1

  #

Fixes: 03db8b583d ("perf tools: Fix maps__find_symbol_by_name()")
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/158763967332.30755.4922496724365529088.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-28 10:03:24 -03:00
Masami Hiramatsu
80526491c2 perf probe: Fix to check blacklist address correctly
Fix to check kprobe blacklist address correctly with relocated address
by adjusting debuginfo address.

Since the address in the debuginfo is same as objdump, it is different
from relocated kernel address with KASLR.  Thus, 'perf probe' always
misses to catch the blacklisted addresses.

Without this patch, 'perf probe' can not detect the blacklist addresses
on a KASLR enabled kernel.

  # perf probe kprobe_dispatcher
  Failed to write event: Invalid argument
    Error: Failed to add events.
  #

With this patch, it correctly shows the error message.

  # perf probe kprobe_dispatcher
  kprobe_dispatcher is blacklisted function, skip it.
  Probe point 'kprobe_dispatcher' not found.
    Error: Failed to add events.
  #

Fixes: 9aaf5a5f47 ("perf probe: Check kprobes blacklist when adding new events")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lore.kernel.org/lkml/158763966411.30755.5882376357738273695.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-28 10:03:24 -03:00
Masami Hiramatsu
c6aab66a72 perf probe: Accept the instance number of kretprobe event
Since the commit 6a13a0d7b4 ("ftrace/kprobe: Show the maxactive number
on kprobe_events") introduced to show the instance number of kretprobe
events, the length of the 1st format of the kprobe event will not 1, but
it can be longer.  This caused a parser error in perf-probe.

Skip the length check the 1st format of the kprobe event to accept this
instance number.

Without this fix:

  # perf probe -a vfs_read%return
  Added new event:
    probe:vfs_read__return (on vfs_read%return)

  You can now use it in all perf tools, such as:

  	perf record -e probe:vfs_read__return -aR sleep 1

  # perf probe -l
  Semantic error :Failed to parse event name: r16:probe/vfs_read__return
    Error: Failed to show event list.

And with this fixes:

  # perf probe -a vfs_read%return
  ...
  # perf probe -l
    probe:vfs_read__return (on vfs_read%return)

Fixes: 6a13a0d7b4 ("ftrace/kprobe: Show the maxactive number on kprobe_events")
Reported-by: Yuxuan Shui <yshuiv7@gmail.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Yuxuan Shui <yshuiv7@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207587
Link: http://lore.kernel.org/lkml/158877535215.26469.1113127926699134067.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-28 10:03:24 -03:00
Arnaldo Carvalho de Melo
c54d241b35 perf maps: Rename map_groups.h to maps.h
One more step in the merge of 'struct maps' with 'struct map_groups'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-9ibtn3vua76f934t7woyf26w@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-26 11:07:46 -03:00
Arnaldo Carvalho de Melo
79b6bb73f8 perf maps: Merge 'struct maps' with 'struct map_groups'
And pick the shortest name: 'struct maps'.

The split existed because we used to have two groups of maps, one for
functions and one for variables, but that only complicated things,
sometimes we needed to figure out what was at some address and then had
to first try it on the functions group and if that failed, fall back to
the variables one.

That split is long gone, so for quite a while we had only one struct
maps per struct map_groups, simplify things by combining those structs.

First patch is the minimum needed to merge both, follow up patches will
rename 'thread->mg' to 'thread->maps', etc.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-hom6639ro7020o708trhxh59@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-26 11:07:46 -03:00
Masami Hiramatsu
cb40273085 perf probe: Trace a magic number if variable is not found
Trace a magic number as immediate value if the target variable is not
found at some probe points which is based on one probe event.

This feature is good for the case if you trace a source code line with
some local variables, which is compiled into several instructions and
some of the variables are optimized out on some instructions.

Even if so, with this feature, perf probe trace a magic number instead
of such disappeared variables and fold those probes on one event.

E.g. without this patch:

  # perf probe -D "pud_page_vaddr pud"
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  Failed to find 'pud' in this function.
  p:probe/pud_page_vaddr _text+23480787 pud=%ax:x64
  p:probe/pud_page_vaddr _text+23808453 pud=%bp:x64
  p:probe/pud_page_vaddr _text+23558082 pud=%ax:x64
  p:probe/pud_page_vaddr _text+328373 pud=%r8:x64
  p:probe/pud_page_vaddr _text+348448 pud=%bx:x64
  p:probe/pud_page_vaddr _text+23816818 pud=%bx:x64

With this patch:

  # perf probe -D "pud_page_vaddr pud" | head
  spurious_kernel_fault is blacklisted function, skip it.
  vmalloc_fault is blacklisted function, skip it.
  p:probe/pud_page_vaddr _text+23480787 pud=%ax:x64
  p:probe/pud_page_vaddr _text+149051 pud=\deade12d:x64
  p:probe/pud_page_vaddr _text+23808453 pud=%bp:x64
  p:probe/pud_page_vaddr _text+315926 pud=\deade12d:x64
  p:probe/pud_page_vaddr _text+23807209 pud=\deade12d:x64
  p:probe/pud_page_vaddr _text+23557365 pud=%ax:x64
  p:probe/pud_page_vaddr _text+314097 pud=%di:x64
  p:probe/pud_page_vaddr _text+314015 pud=\deade12d:x64
  p:probe/pud_page_vaddr _text+313893 pud=\deade12d:x64
  p:probe/pud_page_vaddr _text+324083 pud=\deade12d:x64

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Link: http://lore.kernel.org/lkml/157406476931.24476.6261475888681844285.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-18 19:09:23 -03:00
Masami Hiramatsu
72363540c0 perf probe: Support multiprobe event
Support multiprobe event if the event is based on function and lines and
kernel supports it. In this case, perf probe creates the first probe
with an event, and tries to append following probes on that event, since
those probes must be on the same source code line.

Before this patch;

  # perf probe -a vfs_read:18
  Added new events:
    probe:vfs_read_L18   (on vfs_read:18)
    probe:vfs_read_L18_1 (on vfs_read:18)

  You can now use it in all perf tools, such as:

  	perf record -e probe:vfs_read_L18_1 -aR sleep 1

  #

After this patch (on multiprobe supported kernel)
  # perf probe -a vfs_read:18
  Added new events:
    probe:vfs_read_L18   (on vfs_read:18)
    probe:vfs_read_L18   (on vfs_read:18)

  You can now use it in all perf tools, such as:

  	perf record -e probe:vfs_read_L18 -aR sleep 1

  #

Committer testing:

On a kernel that doesn't support multiprobe events, after this patch:

  # uname -a
  Linux quaco 5.3.8-200.fc30.x86_64 #1 SMP Tue Oct 29 14:46:22 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
  # grep append /sys/kernel/debug/tracing/README
  	    be modified by appending '.descending' or '.ascending' to a
  	    can be modified by appending any of the following modifiers
  #
  # perf probe -a vfs_read:18
  Added new events:
    probe:vfs_read_L18   (on vfs_read:18)
    probe:vfs_read_L18_1 (on vfs_read:18)

  You can now use it in all perf tools, such as:

  	perf record -e probe:vfs_read_L18_1 -aR sleep 1

  # perf probe -l
    probe:vfs_read_L18   (on vfs_read:18@fs/read_write.c)
    probe:vfs_read_L18_1 (on vfs_read:18@fs/read_write.c)
  #

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Link: http://lore.kernel.org/lkml/157406475010.24476.586290752591512351.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-11-18 19:03:38 -03:00