Commit Graph

1994 Commits

Author SHA1 Message Date
Kees Cook
52a9dab6d8 libsubcmd: Fix use-after-free for realloc(..., 0)
GCC 12 correctly reports a potential use-after-free condition in the
xrealloc helper. Fix the warning by avoiding an implicit "free(ptr)"
when size == 0:

In file included from help.c:12:
In function 'xrealloc',
    inlined from 'add_cmdname' at help.c:24:2: subcmd-util.h:56:23: error: pointer may be used after 'realloc' [-Werror=use-after-free]
   56 |                 ret = realloc(ptr, size);
      |                       ^~~~~~~~~~~~~~~~~~
subcmd-util.h:52:21: note: call to 'realloc' here
   52 |         void *ret = realloc(ptr, size);
      |                     ^~~~~~~~~~~~~~~~~~
subcmd-util.h:58:31: error: pointer may be used after 'realloc' [-Werror=use-after-free]
   58 |                         ret = realloc(ptr, 1);
      |                               ^~~~~~~~~~~~~~~
subcmd-util.h:52:21: note: call to 'realloc' here
   52 |         void *ret = realloc(ptr, size);
      |                     ^~~~~~~~~~~~~~~~~~

Fixes: 2f4ce5ec1d ("perf tools: Finalize subcmd independence")
Reported-by: Valdis Klētnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Kees Kook <keescook@chromium.org>
Tested-by: Valdis Klētnieks <valdis.kletnieks@vt.edu>
Tested-by: Justin M. Forbes <jforbes@fedoraproject.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: linux-hardening@vger.kernel.org
Cc: Valdis Klētnieks <valdis.kletnieks@vt.edu>
Link: http://lore.kernel.org/lkml/20220213182443.4037039-1-keescook@chromium.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-02-16 13:49:25 -03:00
Jiri Olsa
30d1c4d947 libperf: Fix perf_cpu_map__for_each_cpu macro
Tzvetomir Stoyanov reported an issue with using macro
perf_cpu_map__for_each_cpu using private perf_cpu object.

The issue is caused by recent change that wrapped cpu in struct perf_cpu
to distinguish it from cpu indexes. We need to make struct perf_cpu
public.

Add a simple test for using the perf_cpu_map__for_each_cpu macro.

Fixes: 6d18804b96 ("perf cpumap: Give CPUs their own type")
Reported-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.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/20220215153713.31395-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-02-16 13:49:25 -03:00
Rob Herring
096972f558 libperf: Fix 32-bit build for tests uint64_t printf
Commit a7f3713f6b ("libperf tests: Add test_stat_multiplexing test")
added printf's of 64-bit ints using %lu which doesn't work on 32-bit
builds:

  tests/test-evlist.c:529:29: error: format ‘%lu’ expects argument of type \
    ‘long unsigned int’, but argument 4 has type ‘uint64_t’ {aka ‘long long unsigned int’} [-Werror=format=]

Use PRIu64 instead which works on both 32-bit and 64-bit systems.

Fixes: a7f3713f6b ("libperf tests: Add test_stat_multiplexing test")
Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.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>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Link: https://lore.kernel.org/r/20220201213903.699656-1-robh@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-02-16 13:49:24 -03:00
Rob Herring
407eb43ae8 libperf: Add arm64 support to perf_mmap__read_self()
Add the arm64 variants for read_perf_counter() and read_timestamp().
Unfortunately the counter number is encoded into the instruction, so the
code is a bit verbose to enumerate all possible counters.

Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lore.kernel.org/r/20220201214056.702854-1-robh@kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-perf-users@vger.kernel.org
2022-02-06 09:14:27 -03:00
Linus Torvalds
40c843218f perf tools changes for v5.17: 2nd batch
- Fix printing 'phys_addr' in 'perf script'.
 
 - Fix failure to add events with 'perf probe' in ppc64 due to not removing
   leading dot (ppc64 ABIv1).
 
 - Fix cpu_map__item() python binding building.
 
 - Support event alias in form foo-bar-baz, add pmu-events and parse-event tests
   for it.
 
 - No need to setup affinities when starting a workload or attaching to a pid.
 
 - Use path__join() to compose a path instead of ad-hoc snprintf() equivalent.
 
 - Override attr->sample_period for non-libpfm4 events.
 
 - Use libperf cpumap APIs instead of accessing the internal state directly.
 
 - Sync x86 arch prctl headers and files changed by the new
   set_mempolicy_home_node syscall with the kernel sources.
 
 - Remove duplicate include in cpumap.h.
 
 - Remove redundant err variable.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-tools-for-v5.17-2022-01-22' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull more perf tools updates from Arnaldo Carvalho de Melo:

 - Fix printing 'phys_addr' in 'perf script'.

 - Fix failure to add events with 'perf probe' in ppc64 due to not
   removing leading dot (ppc64 ABIv1).

 - Fix cpu_map__item() python binding building.

 - Support event alias in form foo-bar-baz, add pmu-events and
   parse-event tests for it.

 - No need to setup affinities when starting a workload or attaching to
   a pid.

 - Use path__join() to compose a path instead of ad-hoc snprintf()
   equivalent.

 - Override attr->sample_period for non-libpfm4 events.

 - Use libperf cpumap APIs instead of accessing the internal state
   directly.

 - Sync x86 arch prctl headers and files changed by the new
   set_mempolicy_home_node syscall with the kernel sources.

 - Remove duplicate include in cpumap.h.

 - Remove redundant err variable.

* tag 'perf-tools-for-v5.17-2022-01-22' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  perf tools: Remove redundant err variable
  perf test: Add parse-events test for aliases with hyphens
  perf test: Add pmu-events test for aliases with hyphens
  perf parse-events: Support event alias in form foo-bar-baz
  perf evsel: Override attr->sample_period for non-libpfm4 events
  perf cpumap: Remove duplicate include in cpumap.h
  perf cpumap: Migrate to libperf cpumap api
  perf python: Fix cpu_map__item() building
  perf script: Fix printing 'phys_addr' failure issue
  tools headers UAPI: Sync files changed by new set_mempolicy_home_node syscall
  tools headers UAPI: Sync x86 arch prctl headers with the kernel sources
  perf machine: Use path__join() to compose a path instead of snprintf(dir, '/', filename)
  perf evlist: No need to setup affinities when disabling events for pid targets
  perf evlist: No need to setup affinities when enabling events for pid targets
  perf stat: No need to setup affinities when starting a workload
  perf affinity: Allow passing a NULL arg to affinity__cleanup()
  perf probe: Fix ppc64 'perf probe add events failed' case
2022-01-23 08:14:21 +02:00
Linus Torvalds
3689f9f8b0 bitmap patches for 5.17-rc1
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Merge tag 'bitmap-5.17-rc1' of git://github.com/norov/linux

Pull bitmap updates from Yury Norov:

 - introduce for_each_set_bitrange()

 - use find_first_*_bit() instead of find_next_*_bit() where possible

 - unify for_each_bit() macros

* tag 'bitmap-5.17-rc1' of git://github.com/norov/linux:
  vsprintf: rework bitmap_list_string
  lib: bitmap: add performance test for bitmap_print_to_pagebuf
  bitmap: unify find_bit operations
  mm/percpu: micro-optimize pcpu_is_populated()
  Replace for_each_*_bit_from() with for_each_*_bit() where appropriate
  find: micro-optimize for_each_{set,clear}_bit()
  include/linux: move for_each_bit() macros from bitops.h to find.h
  cpumask: replace cpumask_next_* with cpumask_first_* where appropriate
  tools: sync tools/bitmap with mother linux
  all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate
  cpumask: use find_first_and_bit()
  lib: add find_first_and_bit()
  arch: remove GENERIC_FIND_FIRST_BIT entirely
  include: move find.h from asm_generic to linux
  bitops: move find_bit_*_le functions from le.h to find.h
  bitops: protect find_first_{,zero}_bit properly
2022-01-23 06:20:44 +02:00
Ian Rogers
4402869939 perf cpumap: Migrate to libperf cpumap api
Switch from directly accessing the perf_cpu_map to using the appropriate
libperf API when possible. Using the API simplifies the job of
refactoring use of perf_cpu_map.

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: James Clark <james.clark@arm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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/20220122045811.3402706-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-22 17:08:42 -03:00
Linus Torvalds
57d17378a4 perf tools changes for v5.17: 1st batch
New features:
 
 - Add 'trace' subcommand for 'perf ftrace', setting the stage for more
   'perf ftrace' subcommands. Not using a subcommand yields the previous
   behaviour of 'perf ftrace'.
 
 - Add 'latency' subcommand to 'perf ftrace', that can use the function
   graph tracer or a BPF optimized one, via the -b/--use-bpf option.
 
   E.g.:
 
   $ sudo perf ftrace latency -a -T mutex_lock sleep 1
   #   DURATION     |      COUNT | GRAPH                          |
        0 - 1    us |       4596 | ########################       |
        1 - 2    us |       1680 | #########                      |
        2 - 4    us |       1106 | #####                          |
        4 - 8    us |        546 | ##                             |
        8 - 16   us |        562 | ###                            |
       16 - 32   us |          1 |                                |
       32 - 64   us |          0 |                                |
       64 - 128  us |          0 |                                |
      128 - 256  us |          0 |                                |
      256 - 512  us |          0 |                                |
      512 - 1024 us |          0 |                                |
        1 - 2    ms |          0 |                                |
        2 - 4    ms |          0 |                                |
        4 - 8    ms |          0 |                                |
        8 - 16   ms |          0 |                                |
       16 - 32   ms |          0 |                                |
       32 - 64   ms |          0 |                                |
       64 - 128  ms |          0 |                                |
      128 - 256  ms |          0 |                                |
      256 - 512  ms |          0 |                                |
      512 - 1024 ms |          0 |                                |
        1 - ...   s |          0 |                                |
 
   The original implementation of this command was in the bcc tool.
 
 - Support --cputype option for hybrid events in 'perf stat'.
 
 Improvements:
 
 - Call chain improvements for ARM64.
 
 - No need to do any affinity setup when profiling pids.
 
 - Reduce multiplexing with duration_time in 'perf stat' metrics.
 
 - Improve error message for uncore events, stating that some event groups are
   can only be used in system wide (-a) mode.
 
 - perf stat metric group leader fixes/improvements, including arch specific
   changes to better support Intel topdown events.
 
 - Probe non-deprecated sysfs path 1st, i.e. try /sys/devices/system/cpu/cpuN/topology/thread_siblings
   first, then the old /sys/devices/system/cpu/cpuN/topology/core_cpus.
 
 - Disable debuginfod by default in 'perf record', to avoid stalls on distros
   such as Fedora 35.
 
 - Use unbuffered output in 'perf bench' when pipe/tee'ing to a file.
 
 - Enable ignore_missing_thread in 'perf trace'
 
 Fixes:
 
 - Avoid TUI crash when navigating in the annotation of recursive functions.
 
 - Fix hex dump character output in 'perf script'.
 
 - Fix JSON indentation to 4 spaces standard in the ARM vendor event files.
 
 - Fix use after free in metric__new().
 
 - Fix IS_ERR_OR_NULL() usage in the perf BPF loader.
 
 - Fix up cross-arch register support, i.e. when printing register names take
   into account the architecture where the perf.data file was collected.
 
 - Fix SMT fallback with large core counts.
 
 - Don't lower case MetricExpr when parsing JSON files so as not to lose info
   such as the ":G" event modifier in metrics.
 
 perf test:
 
 - Add basic stress test for sigtrap handling to 'perf test'.
 
 - Fix 'perf test' failures on s/390
 
 - Enable system wide for metricgroups test in 'perf test´.
 
 - Use 3 digits for test numbering now we can have more tests.
 
 Arch specific:
 
 - Add events for Arm Neoverse N2 in the ARM JSON vendor event files
 
 - Support PERF_MEM_LVLNUM encodings in powerpc, that came from a single
   patch series, where I incorrectly merged the kernel bits, that were then
   reverted after coordination with Michael Ellerman and Stephen Rothwell.
 
 - Add ARM SPE total latency as PERF_SAMPLE_WEIGHT.
 
 - Update AMD documentation, with info on raw event encoding.
 
 - Add support for global and local variants of the "p_stage_cyc" sort key,
   applicable to perf.data files collected on powerpc.
 
 - Remove duplicate and incorrect aux size checks in the ARM CoreSight ETM code.
 
 Refactorings:
 
 - Add a perf_cpu abstraction to disambiguate CPUs and CPU map indexes, fixing
   problems along the way.
 
 - Document CPU map methods.
 
 UAPI sync:
 
 - Update arch/x86/lib/mem{cpy,set}_64.S copies used in 'perf bench mem memcpy'
 
 - Sync UAPI files with the kernel sources: drm, msr-index, cpufeatures.
 
 Build system
 
 - Enable warnings through HOSTCFLAGS.
 
 - Drop requirement for libstdc++.so for libopencsd check
 
 libperf:
 
 - Make libperf adopt perf_counts_values__scale() from tools/perf/util/.
 
 - Add a stat multiplexing test to libperf.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-tools-for-v5.17-2022-01-16' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull perf tool updates from Arnaldo Carvalho de Melo:
 "New features:

   - Add 'trace' subcommand for 'perf ftrace', setting the stage for
     more 'perf ftrace' subcommands. Not using a subcommand yields the
     previous behaviour of 'perf ftrace'.

   - Add 'latency' subcommand to 'perf ftrace', that can use the
     function graph tracer or a BPF optimized one, via the -b/--use-bpf
     option.

     E.g.:

	$ sudo perf ftrace latency -a -T mutex_lock sleep 1
	#   DURATION     |      COUNT | GRAPH                          |
	     0 - 1    us |       4596 | ########################       |
	     1 - 2    us |       1680 | #########                      |
	     2 - 4    us |       1106 | #####                          |
	     4 - 8    us |        546 | ##                             |
	     8 - 16   us |        562 | ###                            |
	    16 - 32   us |          1 |                                |
	    32 - 64   us |          0 |                                |
	    64 - 128  us |          0 |                                |
	   128 - 256  us |          0 |                                |
	   256 - 512  us |          0 |                                |
	   512 - 1024 us |          0 |                                |
	     1 - 2    ms |          0 |                                |
	     2 - 4    ms |          0 |                                |
	     4 - 8    ms |          0 |                                |
	     8 - 16   ms |          0 |                                |
	    16 - 32   ms |          0 |                                |
	    32 - 64   ms |          0 |                                |
	    64 - 128  ms |          0 |                                |
	   128 - 256  ms |          0 |                                |
	   256 - 512  ms |          0 |                                |
	   512 - 1024 ms |          0 |                                |
	     1 - ...   s |          0 |                                |

     The original implementation of this command was in the bcc tool.

   - Support --cputype option for hybrid events in 'perf stat'.

  Improvements:

   - Call chain improvements for ARM64.

   - No need to do any affinity setup when profiling pids.

   - Reduce multiplexing with duration_time in 'perf stat' metrics.

   - Improve error message for uncore events, stating that some event
     groups are can only be used in system wide (-a) mode.

   - perf stat metric group leader fixes/improvements, including arch
     specific changes to better support Intel topdown events.

   - Probe non-deprecated sysfs path first, i.e. try the path
     /sys/devices/system/cpu/cpuN/topology/thread_siblings first, then
     the old /sys/devices/system/cpu/cpuN/topology/core_cpus.

   - Disable debuginfod by default in 'perf record', to avoid stalls on
     distros such as Fedora 35.

   - Use unbuffered output in 'perf bench' when pipe/tee'ing to a file.

   - Enable ignore_missing_thread in 'perf trace'

  Fixes:

   - Avoid TUI crash when navigating in the annotation of recursive
     functions.

   - Fix hex dump character output in 'perf script'.

   - Fix JSON indentation to 4 spaces standard in the ARM vendor event
     files.

   - Fix use after free in metric__new().

   - Fix IS_ERR_OR_NULL() usage in the perf BPF loader.

   - Fix up cross-arch register support, i.e. when printing register
     names take into account the architecture where the perf.data file
     was collected.

   - Fix SMT fallback with large core counts.

   - Don't lower case MetricExpr when parsing JSON files so as not to
     lose info such as the ":G" event modifier in metrics.

  perf test:

   - Add basic stress test for sigtrap handling to 'perf test'.

   - Fix 'perf test' failures on s/390

   - Enable system wide for metricgroups test in 'perf test´.

   - Use 3 digits for test numbering now we can have more tests.

  Arch specific:

   - Add events for Arm Neoverse N2 in the ARM JSON vendor event files

   - Support PERF_MEM_LVLNUM encodings in powerpc, that came from a
     single patch series, where I incorrectly merged the kernel bits,
     that were then reverted after coordination with Michael Ellerman
     and Stephen Rothwell.

   - Add ARM SPE total latency as PERF_SAMPLE_WEIGHT.

   - Update AMD documentation, with info on raw event encoding.

   - Add support for global and local variants of the "p_stage_cyc" sort
     key, applicable to perf.data files collected on powerpc.

   - Remove duplicate and incorrect aux size checks in the ARM CoreSight
     ETM code.

  Refactorings:

   - Add a perf_cpu abstraction to disambiguate CPUs and CPU map
     indexes, fixing problems along the way.

   - Document CPU map methods.

  UAPI sync:

   - Update arch/x86/lib/mem{cpy,set}_64.S copies used in 'perf bench
     mem memcpy'

   - Sync UAPI files with the kernel sources: drm, msr-index,
     cpufeatures.

  Build system

   - Enable warnings through HOSTCFLAGS.

   - Drop requirement for libstdc++.so for libopencsd check

  libperf:

   - Make libperf adopt perf_counts_values__scale() from tools/perf/util/.

   - Add a stat multiplexing test to libperf"

* tag 'perf-tools-for-v5.17-2022-01-16' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (115 commits)
  perf record: Disable debuginfod by default
  perf evlist: No need to do any affinity setup when profiling pids
  perf cpumap: Add is_dummy() method
  perf metric: Fix metric_leader
  perf cputopo: Fix CPU topology reading on s/390
  perf metricgroup: Fix use after free in metric__new()
  libperf tests: Update a use of the new cpumap API
  perf arm: Fix off-by-one directory path
  tools arch x86: Sync the msr-index.h copy with the kernel sources
  tools headers cpufeatures: Sync with the kernel sources
  tools headers UAPI: Update tools's copy of drm.h header
  tools arch: Update arch/x86/lib/mem{cpy,set}_64.S copies used in 'perf bench mem memcpy'
  perf pmu-events: Don't lower case MetricExpr
  perf expr: Add debug logging for literals
  perf tools: Probe non-deprecated sysfs path 1st
  perf tools: Fix SMT fallback with large core counts
  perf cpumap: Give CPUs their own type
  perf stat: Correct first_shadow_cpu to return index
  perf script: Fix flipped index and cpu
  perf c2c: Use more intention revealing iterator
  ...
2022-01-18 06:32:11 +02:00
Linus Torvalds
4d66020dce Tracing updates for 5.17:
New:
 
 - The Real Time Linux Analysis (RTLA) tool is added to the tools directory.
 
 - Can safely filter on user space pointers with: field.ustring ~ "match-string"
 
 - eprobes can now be filtered like any other event.
 
 - trace_marker(_raw) now uses stream_open() to allow multiple threads to safely
   write to it. Note, this could possibly break existing user space, but we will
   not know until we hear about it, and then can revert the change if need be.
 
 - New field in events to display when bottom halfs are disabled.
 
 - Sorting of the ftrace functions are now done at compile time instead of
   at bootup.
 
 Infrastructure changes to support future efforts:
 
 - Added __rel_loc type for trace events. Similar to __data_loc but the offset
   to the dynamic data is based off of the location of the descriptor and not
   the beginning of the event. Needed for user defined events.
 
 - Some simplification of event trigger code.
 
 - Make synthetic events process its callback better to not hinder other
   event callbacks that are registered. Needed for user defined events.
 
 And other small fixes and clean ups.
 -
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Merge tag 'trace-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "New:

   - The Real Time Linux Analysis (RTLA) tool is added to the tools
     directory.

   - Can safely filter on user space pointers with: field.ustring ~
     "match-string"

   - eprobes can now be filtered like any other event.

   - trace_marker(_raw) now uses stream_open() to allow multiple threads
     to safely write to it. Note, this could possibly break existing
     user space, but we will not know until we hear about it, and then
     can revert the change if need be.

   - New field in events to display when bottom halfs are disabled.

   - Sorting of the ftrace functions are now done at compile time
     instead of at bootup.

  Infrastructure changes to support future efforts:

   - Added __rel_loc type for trace events. Similar to __data_loc but
     the offset to the dynamic data is based off of the location of the
     descriptor and not the beginning of the event. Needed for user
     defined events.

   - Some simplification of event trigger code.

   - Make synthetic events process its callback better to not hinder
     other event callbacks that are registered. Needed for user defined
     events.

  And other small fixes and cleanups"

* tag 'trace-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (50 commits)
  tracing: Add ustring operation to filtering string pointers
  rtla: Add rtla timerlat hist documentation
  rtla: Add rtla timerlat top documentation
  rtla: Add rtla timerlat documentation
  rtla: Add rtla osnoise hist documentation
  rtla: Add rtla osnoise top documentation
  rtla: Add rtla osnoise man page
  rtla: Add Documentation
  rtla/timerlat: Add timerlat hist mode
  rtla: Add timerlat tool and timelart top mode
  rtla/osnoise: Add the hist mode
  rtla/osnoise: Add osnoise top mode
  rtla: Add osnoise tool
  rtla: Helper functions for rtla
  rtla: Real-Time Linux Analysis tool
  tracing/osnoise: Properly unhook events if start_per_cpu_kthreads() fails
  tracing: Remove duplicate warnings when calling trace_create_file()
  tracing/kprobes: 'nmissed' not showed correctly for kretprobe
  tracing: Add test for user space strings when filtering on string pointers
  tracing: Have syscall trace events use trace_event_buffer_lock_reserve()
  ...
2022-01-16 10:15:32 +02:00
Yury Norov
4ade0818cf tools: sync tools/bitmap with mother linux
Remove tools/include/asm-generic/bitops/find.h and copy
include/linux/bitmap.h to tools. find_*_le() functions are not copied
because not needed in tools.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2022-01-15 08:47:31 -08:00
Ian Rogers
99fc11bb5b libperf tests: Update a use of the new cpumap API
Fixes a build breakage.

Fixes: 6d18804b96 ("perf cpumap: Give CPUs their own type")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: colin ian king <colin.king@intel.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: Peter Zijlstra <peterz@infradead.org>
Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
Link: http://lore.kernel.org/lkml/20220114065105.1806542-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-14 11:36:03 -03:00
Arnaldo Carvalho de Melo
1aa77e716c Merge remote-tracking branch 'torvalds/master' into perf/core
To pick up fixes and get in line with other trees, powerpc kernel
mostly this time, but BPF as well.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-13 10:20:59 -03:00
Ian Rogers
6d18804b96 perf cpumap: Give CPUs their own type
A common problem is confusing CPU map indices with the CPU, by wrapping
the CPU with a struct then this is avoided. This approach is similar to
atomic_t.

Committer notes:

To make it build with BUILD_BPF_SKEL=1 these files needed the
conversions to 'struct perf_cpu' usage:

  tools/perf/util/bpf_counter.c
  tools/perf/util/bpf_counter_cgroup.c
  tools/perf/util/bpf_ftrace.c

Also perf_env__get_cpu() was removed back in "perf cpumap: Switch
cpu_map__build_map to cpu function".

Additionally these needed to be fixed for the ARM builds to complete:

  tools/perf/arch/arm/util/cs-etm.c
  tools/perf/arch/arm64/util/pmu.c

Suggested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Vineet Singh <vineet.singh@intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: zhengjun.xing@intel.com
Link: https://lore.kernel.org/r/20220105061351.120843-49-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-12 14:28:23 -03:00
Ian Rogers
91802e73f7 libperf: Sync evsel documentation
cpu was renamed cpu_map_idx, for clarity.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Vineet Singh <vineet.singh@intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: zhengjun.xing@intel.com
Link: https://lore.kernel.org/r/20220105061351.120843-44-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-12 14:28:23 -03:00
Ian Rogers
80b82f3b65 libperf: Allow NULL in perf_cpu_map__idx()
Return -1, not found, if NULL is passed.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Vineet Singh <vineet.singh@intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: zhengjun.xing@intel.com
Link: https://lore.kernel.org/r/20220105061351.120843-34-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-12 14:28:22 -03:00
Ian Rogers
47ffe80667 libperf: Use cpu not index for evsel mmap
Fix issue where evsel's CPU map index was being used as the mmap cpu.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Vineet Singh <vineet.singh@intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: zhengjun.xing@intel.com
Link: https://lore.kernel.org/r/20220105061351.120843-29-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-12 14:28:22 -03:00
Ian Rogers
7e3d1784c8 libperf: Switch cpu to more accurate cpu_map_idx
Modify variable names and adopt perf_cpu_map__for_each_cpu() in
perf_evsel__open().

Renaming is done by looking for consistency in API usage.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Vineet Singh <vineet.singh@intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: zhengjun.xing@intel.com
Link: https://lore.kernel.org/r/20220105061351.120843-28-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-12 14:28:22 -03:00
Ian Rogers
dfc66beff7 perf cpumap: Move 'has' function to libperf
Make the cpu map argument const for consistency with the rest of the
API. Modify cpu_map__idx accordingly.

Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
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: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Vineet Singh <vineet.singh@intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: zhengjun.xing@intel.com
Link: https://lore.kernel.org/r/20220105061351.120843-21-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-12 14:28:22 -03:00
Ian Rogers
818ab78c03 libperf: Add comments to 'struct perf_cpu_map'
A particular observed problem is confusing the index with the CPU value,
documentation should hopefully reduce this type of problem.

Reviewed-by: James Clark <james.clark@arm.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Vineet Singh <vineet.singh@intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: zhengjun.xing@intel.com
Link: https://lore.kernel.org/r/20220105061351.120843-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-12 14:28:21 -03:00
Grant Seltzer
e59618f0f4 libbpf: Add documentation for bpf_map batch operations
This adds documention for:

- bpf_map_delete_batch()
- bpf_map_lookup_batch()
- bpf_map_lookup_and_delete_batch()
- bpf_map_update_batch()

This also updates the public API for the `keys` parameter
of `bpf_map_delete_batch()`, and both the
`keys` and `values` parameters of `bpf_map_update_batch()`
to be constants.

Signed-off-by: Grant Seltzer <grantseltzer@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220106201304.112675-1-grantseltzer@gmail.com
2022-01-06 15:12:42 -08:00
Christy Lee
5f60826428 libbpf 1.0: Deprecate bpf_object__find_map_by_offset() API
API created with simplistic assumptions about BPF map definitions.
It hasn’t worked for a while, deprecate it in preparation for
libbpf 1.0.

  [0] Closes: https://github.com/libbpf/libbpf/issues/302

Signed-off-by: Christy Lee <christylee@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220105003120.2222673-1-christylee@fb.com
2022-01-05 16:11:32 -08:00
Christy Lee
9855c131b9 libbpf 1.0: Deprecate bpf_map__is_offload_neutral()
Deprecate bpf_map__is_offload_neutral(). It’s most probably broken
already. PERF_EVENT_ARRAY isn’t the only map that’s not suitable
for hardware offloading. Applications can directly check map type
instead.

  [0] Closes: https://github.com/libbpf/libbpf/issues/306

Signed-off-by: Christy Lee <christylee@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220105000601.2090044-1-christylee@fb.com
2022-01-05 16:09:06 -08:00
Qiang Wang
51a33c60f1 libbpf: Support repeated legacy kprobes on same function
If repeated legacy kprobes on same function in one process,
libbpf will register using the same probe name and got -EBUSY
error. So append index to the probe name format to fix this
problem.

Co-developed-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Qiang Wang <wangqiang.wq.frank@bytedance.com>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211227130713.66933-2-wangqiang.wq.frank@bytedance.com
2022-01-05 15:38:21 -08:00
Qiang Wang
71cff670ba libbpf: Use probe_name for legacy kprobe
Fix a bug in commit 46ed5fc33d, which wrongly used the
func_name instead of probe_name to register legacy kprobe.

Fixes: 46ed5fc33d ("libbpf: Refactor and simplify legacy kprobe code")
Co-developed-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Qiang Wang <wangqiang.wq.frank@bytedance.com>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Hengqi Chen <hengqi.chen@gmail.com>
Reviewed-by: Hengqi Chen <hengqi.chen@gmail.com>
Link: https://lore.kernel.org/bpf/20211227130713.66933-1-wangqiang.wq.frank@bytedance.com
2022-01-05 15:38:21 -08:00
Christy Lee
7218c28c87 libbpf: Deprecate bpf_perf_event_read_simple() API
With perf_buffer__poll() and perf_buffer__consume() APIs available,
there is no reason to expose bpf_perf_event_read_simple() API to
users. If users need custom perf buffer, they could re-implement
the function.

Mark bpf_perf_event_read_simple() and move the logic to a new
static function so it can still be called by other functions in the
same file.

  [0] Closes: https://github.com/libbpf/libbpf/issues/310

Signed-off-by: Christy Lee <christylee@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211229204156.13569-1-christylee@fb.com
2022-01-05 15:27:43 -08:00
Andrii Nakryiko
5b3d729877 libbpf: Improve LINUX_VERSION_CODE detection
Ubuntu reports incorrect kernel version through uname(), which on older
kernels leads to kprobe BPF programs failing to load due to the version
check mismatch.

Accommodate Ubuntu's quirks with LINUX_VERSION_CODE by using
Ubuntu-specific /proc/version_code to fetch major/minor/patch versions
to form LINUX_VERSION_CODE.

While at it, consolide libbpf's kernel version detection code between
libbpf.c and libbpf_probes.c.

  [0] Closes: https://github.com/libbpf/libbpf/issues/421

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20211222231003.2334940-1-andrii@kernel.org
2021-12-28 19:20:31 -08:00
Andrii Nakryiko
f60edf5b53 libbpf: Use 100-character limit to make bpf_tracing.h easier to read
Improve bpf_tracing.h's macro definition readability by keeping them
single-line and better aligned. This makes it easier to follow all those
variadic patterns.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20211222213924.1869758-2-andrii@kernel.org
2021-12-28 19:14:45 -08:00
Andrii Nakryiko
3cc31d7940 libbpf: Normalize PT_REGS_xxx() macro definitions
Refactor PT_REGS macros definitions in  bpf_tracing.h to avoid excessive
duplication. We currently have classic PT_REGS_xxx() and CO-RE-enabled
PT_REGS_xxx_CORE(). We are about to add also _SYSCALL variants, which
would require excessive copying of all the per-architecture definitions.

Instead, separate architecture-specific field/register names from the
final macro that utilize them. That way for upcoming _SYSCALL variants
we'll be able to just define x86_64 exception and otherwise have one
common set of _SYSCALL macro definitions common for all architectures.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/20211222213924.1869758-1-andrii@kernel.org
2021-12-28 19:14:44 -08:00
Jiri Olsa
5652b807b7 libbpf: Do not use btf_dump__new() macro in C++ mode
As reported in here [0], C++ compilers don't support
__builtin_types_compatible_p(), so at least don't screw up compilation
for them and let C++ users pick btf_dump__new vs
btf_dump__new_deprecated explicitly.

  [0] https://github.com/libbpf/libbpf/issues/283#issuecomment-986100727

Fixes: 6084f5dc92 ("libbpf: Ensure btf_dump__new() and btf_dump_opts are future-proof")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20211223131736.483956-1-jolsa@kernel.org
2021-12-23 10:23:16 -08:00
Andrii Nakryiko
878d8def06 libbpf: Rework feature-probing APIs
Create three extensible alternatives to inconsistently named
feature-probing APIs:

  - libbpf_probe_bpf_prog_type() instead of bpf_probe_prog_type();
  - libbpf_probe_bpf_map_type() instead of bpf_probe_map_type();
  - libbpf_probe_bpf_helper() instead of bpf_probe_helper().

Set up return values such that libbpf can report errors (e.g., if some
combination of input arguments isn't possible to validate, etc), in
addition to whether the feature is supported (return value 1) or not
supported (return value 0).

Also schedule deprecation of those three APIs. Also schedule deprecation
of bpf_probe_large_insn_limit().

Also fix all the existing detection logic for various program and map
types that never worked:

  - BPF_PROG_TYPE_LIRC_MODE2;
  - BPF_PROG_TYPE_TRACING;
  - BPF_PROG_TYPE_LSM;
  - BPF_PROG_TYPE_EXT;
  - BPF_PROG_TYPE_SYSCALL;
  - BPF_PROG_TYPE_STRUCT_OPS;
  - BPF_MAP_TYPE_STRUCT_OPS;
  - BPF_MAP_TYPE_BLOOM_FILTER.

Above prog/map types needed special setups and detection logic to work.
Subsequent patch adds selftests that will make sure that all the
detection logic keeps working for all current and future program and map
types, avoiding otherwise inevitable bit rot.

  [0] Closes: https://github.com/libbpf/libbpf/issues/312

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Dave Marchevsky <davemarchevsky@fb.com>
Cc: Julia Kartseva <hex@fb.com>
Link: https://lore.kernel.org/bpf/20211217171202.3352835-2-andrii@kernel.org
2021-12-17 23:10:48 +01:00
Jean-Philippe Brucker
4980beb4cd tools/libbpf: Enable cross-building with clang
Cross-building using clang requires passing the "-target" flag rather
than using the CROSS_COMPILE prefix. Makefile.include transforms
CROSS_COMPILE into CLANG_CROSS_FLAGS. Add them to the CFLAGS.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20211216163842.829836-4-jean-philippe@linaro.org
2021-12-16 12:15:05 -08:00
Colin Ian King
017f7d1fac libperf tests: Fix a spelling mistake "Runnnig" -> "Running"
There is a spelling mistake in a __T_VERBOSE message. Fix it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
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>
Cc: kernel-janitors@vger.kernel.org
Link: http://lore.kernel.org/lkml/20211212222122.478537-1-colin.i.king@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-12-16 12:18:12 -03:00
Andrii Nakryiko
f97982398c libbpf: Avoid reading past ELF data section end when copying license
Fix possible read beyond ELF "license" data section if the license
string is not properly zero-terminated. Use the fact that libbpf_strlcpy
never accesses the (N-1)st byte of the source string because it's
replaced with '\0' anyways.

If this happens, it's a violation of contract between libbpf and a user,
but not handling this more robustly upsets CIFuzz, so given the fix is
trivial, let's fix the potential issue.

Fixes: 9fc205b413 ("libbpf: Add sane strncpy alternative and use it internally")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211214232054.3458774-1-andrii@kernel.org
2021-12-14 21:59:33 -08:00
Kui-Feng Lee
0da2596f34 libbpf: Mark bpf_object__find_program_by_title API deprecated.
Deprecate this API since v0.7.  All callers should move to
bpf_object__find_program_by_name if possible, otherwise use
bpf_object__for_each_program to find a program out from a given
section.

[0] Closes: https://github.com/libbpf/libbpf/issues/292

Signed-off-by: Kui-Feng Lee <kuifeng@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211214035931.1148209-5-kuifeng@fb.com
2021-12-14 14:38:06 -08:00
Andrii Nakryiko
e542f2c4cd libbpf: Auto-bump RLIMIT_MEMLOCK if kernel needs it for BPF
The need to increase RLIMIT_MEMLOCK to do anything useful with BPF is
one of the first extremely frustrating gotchas that all new BPF users go
through and in some cases have to learn it a very hard way.

Luckily, starting with upstream Linux kernel version 5.11, BPF subsystem
dropped the dependency on memlock and uses memcg-based memory accounting
instead. Unfortunately, detecting memcg-based BPF memory accounting is
far from trivial (as can be evidenced by this patch), so in practice
most BPF applications still do unconditional RLIMIT_MEMLOCK increase.

As we move towards libbpf 1.0, it would be good to allow users to forget
about RLIMIT_MEMLOCK vs memcg and let libbpf do the sensible adjustment
automatically. This patch paves the way forward in this matter. Libbpf
will do feature detection of memcg-based accounting, and if detected,
will do nothing. But if the kernel is too old, just like BCC, libbpf
will automatically increase RLIMIT_MEMLOCK on behalf of user
application ([0]).

As this is technically a breaking change, during the transition period
applications have to opt into libbpf 1.0 mode by setting
LIBBPF_STRICT_AUTO_RLIMIT_MEMLOCK bit when calling
libbpf_set_strict_mode().

Libbpf allows to control the exact amount of set RLIMIT_MEMLOCK limit
with libbpf_set_memlock_rlim_max() API. Passing 0 will make libbpf do
nothing with RLIMIT_MEMLOCK. libbpf_set_memlock_rlim_max() has to be
called before the first bpf_prog_load(), bpf_btf_load(), or
bpf_object__load() call, otherwise it has no effect and will return
-EBUSY.

  [0] Closes: https://github.com/libbpf/libbpf/issues/369

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211214195904.1785155-2-andrii@kernel.org
2021-12-14 22:16:45 +01:00
Andrii Nakryiko
9fc205b413 libbpf: Add sane strncpy alternative and use it internally
strncpy() has a notoriously error-prone semantics which makes GCC
complain about it a lot (and quite often completely completely falsely
at that). Instead of pleasing GCC all the time (-Wno-stringop-truncation
is unfortunately only supported by GCC, so it's a bit too messy to just
enable it in Makefile), add libbpf-internal libbpf_strlcpy() helper
which follows what FreeBSD's strlcpy() does and what most people would
expect from strncpy(): copies up to N-1 first bytes from source string
into destination string and ensures zero-termination afterwards.

Replace all the relevant uses of strncpy/strncat/memcpy in libbpf with
libbpf_strlcpy().

This also fixes the issue reported by Emmanuel Deloget in xsk.c where
memcpy() could access source string beyond its end.

Fixes: 2f6324a393 (libbpf: Support shared umems between queues and devices)
Reported-by: Emmanuel Deloget <emmanuel.deloget@eho.link>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211211004043.2374068-1-andrii@kernel.org
2021-12-14 15:47:56 +01:00
Andrii Nakryiko
4581e676d3 libbpf: Fix potential uninit memory read
In case of BPF_CORE_TYPE_ID_LOCAL we fill out target result explicitly.
But targ_res itself isn't initialized in such a case, and subsequent
call to bpf_core_patch_insn() might read uninitialized field (like
fail_memsz_adjust in this case). So ensure that targ_res is
zero-initialized for BPF_CORE_TYPE_ID_LOCAL case.

This was reported by Coverity static analyzer.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211214010032.3843804-1-andrii@kernel.org
2021-12-14 15:37:58 +01:00
Grant Seltzer
f742fc68ac libbpf: Add doc comments for bpf_program__(un)pin()
This adds doc comments for the two bpf_program pinning functions,
bpf_program__pin() and bpf_program__unpin()

Signed-off-by: Grant Seltzer <grantseltzer@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211209232222.541733-1-grantseltzer@gmail.com
2021-12-13 13:55:53 -08:00
Andrii Nakryiko
4b443bc178 libbpf: Don't validate TYPE_ID relo's original imm value
During linking, type IDs in the resulting linked BPF object file can
change, and so ldimm64 instructions corresponding to
BPF_CORE_TYPE_ID_TARGET and BPF_CORE_TYPE_ID_LOCAL CO-RE relos can get
their imm value out of sync with actual CO-RE relocation information
that's updated by BPF linker properly during linking process.

We could teach BPF linker to adjust such instructions, but it feels
a bit too much for linker to re-implement good chunk of
bpf_core_patch_insns logic just for this. This is a redundant safety
check for TYPE_ID relocations, as the real validation is in matching
CO-RE specs, so if that works fine, it's very unlikely that there is
something wrong with the instruction itself.

So, instead, teach libbpf (and kernel) to ignore insn->imm for
BPF_CORE_TYPE_ID_TARGET and BPF_CORE_TYPE_ID_LOCAL relos.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211213010706.100231-1-andrii@kernel.org
2021-12-12 17:26:24 -08:00
Alexei Starovoitov
259172bb65 libbpf: Fix gen_loader assumption on number of programs.
libbpf's obj->nr_programs includes static and global functions. That number
could be higher than the actual number of bpf programs going be loaded by
gen_loader. Passing larger nr_programs to bpf_gen__init() doesn't hurt. Those
exra stack slots will stay as zero. bpf_gen__finish() needs to check that
actual number of progs that gen_loader saw is less than or equal to
obj->nr_programs.

Fixes: ba05fd36b8 ("libbpf: Perform map fd cleanup for gen_loader in case of error")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2021-12-11 17:16:19 -08:00
Jakub Kicinski
be3158290d Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Andrii Nakryiko says:

====================
bpf-next 2021-12-10 v2

We've added 115 non-merge commits during the last 26 day(s) which contain
a total of 182 files changed, 5747 insertions(+), 2564 deletions(-).

The main changes are:

1) Various samples fixes, from Alexander Lobakin.

2) BPF CO-RE support in kernel and light skeleton, from Alexei Starovoitov.

3) A batch of new unified APIs for libbpf, logging improvements, version
   querying, etc. Also a batch of old deprecations for old APIs and various
   bug fixes, in preparation for libbpf 1.0, from Andrii Nakryiko.

4) BPF documentation reorganization and improvements, from Christoph Hellwig
   and Dave Tucker.

5) Support for declarative initialization of BPF_MAP_TYPE_PROG_ARRAY in
   libbpf, from Hengqi Chen.

6) Verifier log fixes, from Hou Tao.

7) Runtime-bounded loops support with bpf_loop() helper, from Joanne Koong.

8) Extend branch record capturing to all platforms that support it,
   from Kajol Jain.

9) Light skeleton codegen improvements, from Kumar Kartikeya Dwivedi.

10) bpftool doc-generating script improvements, from Quentin Monnet.

11) Two libbpf v0.6 bug fixes, from Shuyi Cheng and Vincent Minet.

12) Deprecation warning fix for perf/bpf_counter, from Song Liu.

13) MAX_TAIL_CALL_CNT unification and MIPS build fix for libbpf,
    from Tiezhu Yang.

14) BTF_KING_TYPE_TAG follow-up fixes, from Yonghong Song.

15) Selftests fixes and improvements, from Ilya Leoshkevich, Jean-Philippe
    Brucker, Jiri Olsa, Maxim Mikityanskiy, Tirthendu Sarkar, Yucong Sun,
    and others.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (115 commits)
  libbpf: Add "bool skipped" to struct bpf_map
  libbpf: Fix typo in btf__dedup@LIBBPF_0.0.2 definition
  bpftool: Switch bpf_object__load_xattr() to bpf_object__load()
  selftests/bpf: Remove the only use of deprecated bpf_object__load_xattr()
  selftests/bpf: Add test for libbpf's custom log_buf behavior
  selftests/bpf: Replace all uses of bpf_load_btf() with bpf_btf_load()
  libbpf: Deprecate bpf_object__load_xattr()
  libbpf: Add per-program log buffer setter and getter
  libbpf: Preserve kernel error code and remove kprobe prog type guessing
  libbpf: Improve logging around BPF program loading
  libbpf: Allow passing user log setting through bpf_object_open_opts
  libbpf: Allow passing preallocated log_buf when loading BTF into kernel
  libbpf: Add OPTS-based bpf_btf_load() API
  libbpf: Fix bpf_prog_load() log_buf logic for log_level 0
  samples/bpf: Remove unneeded variable
  bpf: Remove redundant assignment to pointer t
  selftests/bpf: Fix a compilation warning
  perf/bpf_counter: Use bpf_map_create instead of bpf_create_map
  samples: bpf: Fix 'unknown warning group' build warning on Clang
  samples: bpf: Fix xdp_sample_user.o linking with Clang
  ...
====================

Link: https://lore.kernel.org/r/20211210234746.2100561-1-andrii@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-10 15:56:13 -08:00
Shuyi Cheng
229fae38d0 libbpf: Add "bool skipped" to struct bpf_map
Fix error: "failed to pin map: Bad file descriptor, path:
/sys/fs/bpf/_rodata_str1_1."

In the old kernel, the global data map will not be created, see [0]. So
we should skip the pinning of the global data map to avoid
bpf_object__pin_maps returning error. Therefore, when the map is not
created, we mark “map->skipped" as true and then check during relocation
and during pinning.

Fixes: 16e0c35c6f ("libbpf: Load global data maps lazily on legacy kernels")
Signed-off-by: Shuyi Cheng <chengshuyi@linux.alibaba.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
2021-12-10 15:35:30 -08:00
Vincent Minet
b69c5c07a6 libbpf: Fix typo in btf__dedup@LIBBPF_0.0.2 definition
The btf__dedup_deprecated name was misspelled in the definition of the
compat symbol for btf__dedup. This leads it to be missing from the
shared library.

This fixes it.

Fixes: 957d350a8b ("libbpf: Turn btf_dedup_opts into OPTS-based struct")
Signed-off-by: Vincent Minet <vincent@vincent-minet.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211210063112.80047-1-vincent@vincent-minet.net
2021-12-10 15:35:29 -08:00
Andrii Nakryiko
e7b924ca71 libbpf: Deprecate bpf_object__load_xattr()
Deprecate non-extensible bpf_object__load_xattr() in v0.8 ([0]).

With log_level control through bpf_object_open_opts or
bpf_program__set_log_level(), we are finally at the point where
bpf_object__load_xattr() doesn't provide any functionality that can't be
accessed through other (better) ways. The other feature,
target_btf_path, is also controllable through bpf_object_open_opts.

  [0] Closes: https://github.com/libbpf/libbpf/issues/289

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211209193840.1248570-9-andrii@kernel.org
2021-12-10 15:29:18 -08:00
Andrii Nakryiko
b3ce907950 libbpf: Add per-program log buffer setter and getter
Allow to set user-provided log buffer on a per-program basis ([0]). This
gives great deal of flexibility in terms of which programs are loaded
with logging enabled and where corresponding logs go.

Log buffer set with bpf_program__set_log_buf() overrides kernel_log_buf
and kernel_log_size settings set at bpf_object open time through
bpf_object_open_opts, if any.

Adjust bpf_object_load_prog_instance() logic to not perform own log buf
allocation and load retry if custom log buffer is provided by the user.

  [0] Closes: https://github.com/libbpf/libbpf/issues/418

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211209193840.1248570-8-andrii@kernel.org
2021-12-10 15:29:18 -08:00
Andrii Nakryiko
2eda2145eb libbpf: Preserve kernel error code and remove kprobe prog type guessing
Instead of rewriting error code returned by the kernel of prog load with
libbpf-sepcific variants pass through the original error.

There is now also no need to have a backup generic -LIBBPF_ERRNO__LOAD
fallback error as bpf_prog_load() guarantees that errno will be properly
set no matter what.

Also drop a completely outdated and pretty useless BPF_PROG_TYPE_KPROBE
guess logic. It's not necessary and neither it's helpful in modern BPF
applications.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211209193840.1248570-7-andrii@kernel.org
2021-12-10 15:29:18 -08:00
Andrii Nakryiko
ad9a7f9644 libbpf: Improve logging around BPF program loading
Add missing "prog '%s': " prefixes in few places and use consistently
markers for beginning and end of program load logs. Here's an example of
log output:

libbpf: prog 'handler': BPF program load failed: Permission denied
libbpf: -- BEGIN PROG LOAD LOG ---
arg#0 reference type('UNKNOWN ') size cannot be determined: -22
; out1 = in1;
0: (18) r1 = 0xffffc9000cdcc000
2: (61) r1 = *(u32 *)(r1 +0)

...

81: (63) *(u32 *)(r4 +0) = r5
 R1_w=map_value(id=0,off=16,ks=4,vs=20,imm=0) R4=map_value(id=0,off=400,ks=4,vs=16,imm=0)
invalid access to map value, value_size=16 off=400 size=4
R4 min value is outside of the allowed memory range
processed 63 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0
 -- END PROG LOAD LOG --
libbpf: failed to load program 'handler'
libbpf: failed to load object 'test_skeleton'

The entire verifier log, including BEGIN and END markers are now always
youtput during a single print callback call. This should make it much
easier to post-process or parse it, if necessary. It's not an explicit
API guarantee, but it can be reasonably expected to stay like that.

Also __bpf_object__open is renamed to bpf_object_open() as it's always
an adventure to find the exact function that implements bpf_object's
open phase, so drop the double underscored and use internal libbpf
naming convention.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211209193840.1248570-6-andrii@kernel.org
2021-12-10 15:29:17 -08:00
Andrii Nakryiko
e0e3ea888c libbpf: Allow passing user log setting through bpf_object_open_opts
Allow users to provide their own custom log_buf, log_size, and log_level
at bpf_object level through bpf_object_open_opts. This log_buf will be
used during BTF loading. Subsequent patch will use same log_buf during
BPF program loading, unless overriden at per-bpf_program level.

When such custom log_buf is provided, libbpf won't be attempting
retrying loading of BTF to try to provide its own log buffer to capture
kernel's error log output. User is responsible to provide big enough
buffer, otherwise they run a risk of getting -ENOSPC error from the
bpf() syscall.

See also comments in bpf_object_open_opts regarding log_level and
log_buf interactions.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211209193840.1248570-5-andrii@kernel.org
2021-12-10 15:29:17 -08:00
Andrii Nakryiko
1a190d1e8e libbpf: Allow passing preallocated log_buf when loading BTF into kernel
Add libbpf-internal btf_load_into_kernel() that allows to pass
preallocated log_buf and custom log_level to be passed into kernel
during BPF_BTF_LOAD call. When custom log_buf is provided,
btf_load_into_kernel() won't attempt an retry with automatically
allocated internal temporary buffer to capture BTF validation log.

It's important to note the relation between log_buf and log_level, which
slightly deviates from stricter kernel logic. From kernel's POV, if
log_buf is specified, log_level has to be > 0, and vice versa. While
kernel has good reasons to request such "sanity, this, in practice, is
a bit unconvenient and restrictive for libbpf's high-level bpf_object APIs.

So libbpf will allow to set non-NULL log_buf and log_level == 0. This is
fine and means to attempt to load BTF without logging requested, but if
it failes, retry the load with custom log_buf and log_level 1. Similar
logic will be implemented for program loading. In practice this means
that users can provide custom log buffer just in case error happens, but
not really request slower verbose logging all the time. This is also
consistent with libbpf behavior when custom log_buf is not set: libbpf
first tries to load everything with log_level=0, and only if error
happens allocates internal log buffer and retries with log_level=1.

Also, while at it, make BTF validation log more obvious and follow the log
pattern libbpf is using for dumping BPF verifier log during
BPF_PROG_LOAD. BTF loading resulting in an error will look like this:

libbpf: BTF loading error: -22
libbpf: -- BEGIN BTF LOAD LOG ---
magic: 0xeb9f
version: 1
flags: 0x0
hdr_len: 24
type_off: 0
type_len: 1040
str_off: 1040
str_len: 2063598257
btf_total_size: 1753
Total section length too long
-- END BTF LOAD LOG --
libbpf: Error loading .BTF into kernel: -22. BTF is optional, ignoring.

This makes it much easier to find relevant parts in libbpf log output.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211209193840.1248570-4-andrii@kernel.org
2021-12-10 15:29:17 -08:00
Andrii Nakryiko
0ed08d6725 libbpf: Add OPTS-based bpf_btf_load() API
Similar to previous bpf_prog_load() and bpf_map_create() APIs, add
bpf_btf_load() API which is taking optional OPTS struct. Schedule
bpf_load_btf() for deprecation in v0.8 ([0]).

This makes naming consistent with BPF_BTF_LOAD command, sets up an API
for extensibility in the future, moves options parameters (log-related
fields) into optional options, and also allows to pass log_level
directly.

It also removes log buffer auto-allocation logic from low-level API
(consistent with bpf_prog_load() behavior), but preserves a special
treatment of log_level == 0 with non-NULL log_buf, which matches
low-level bpf_prog_load() and high-level libbpf APIs for BTF and program
loading behaviors.

  [0] Closes: https://github.com/libbpf/libbpf/issues/419

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211209193840.1248570-3-andrii@kernel.org
2021-12-10 15:29:17 -08:00