kernel/linux.git/tools/perf/util/session.c, branch v6.3.6

perf session: Show branch speculation info in raw dump

2023-02-02T20:18:31+00:00

Show the branch speculation info if provided by the branch recording hardware feature. This can be useful for purposes of code optimization. E.g. $ perf record -j any,u ./test_branch $ perf report --dump-raw-trace Before: [...] 8380958377610 0x40b178 [0x1b0]: PERF_RECORD_SAMPLE(IP, 0x2): 7952/7952: 0x4f851a period: 48973 addr: 0 ... branch stack: nr:16 ..... 0: 00000000004b52fd -> 00000000004f82c0 0 cycles P 0 ..... 1: ffffffff8220137c -> 00000000004b52f0 0 cycles M 0 ..... 2: 000000000041d1c4 -> 00000000004b52f0 0 cycles P 0 ..... 3: 00000000004e7ead -> 000000000041d1b0 0 cycles M 0 ..... 4: 00000000004e7f91 -> 00000000004e7ead 0 cycles P 0 ..... 5: 00000000004e7ea8 -> 00000000004e7f70 0 cycles P 0 ..... 6: 00000000004e7e52 -> 00000000004e7e98 0 cycles M 0 ..... 7: 00000000004e7e1f -> 00000000004e7e40 0 cycles M 0 ..... 8: 00000000004e7f60 -> 00000000004e7df0 0 cycles P 0 ..... 9: 00000000004e7f58 -> 00000000004e7f60 0 cycles M 0 ..... 10: 000000000041d85d -> 00000000004e7f50 0 cycles P 0 ..... 11: 000000000043306a -> 000000000041d840 0 cycles P 0 ..... 12: ffffffff8220137c -> 0000000000433040 0 cycles M 0 ..... 13: 000000000041e4a1 -> 0000000000433040 0 cycles P 0 ..... 14: ffffffff8220137c -> 000000000041e490 0 cycles M 0 ..... 15: 000000000041d89b -> 000000000041e487 0 cycles P 0 ... thread: test_branch:7952 ...... dso: /data/sandipan/test_branch [...] After: [...] 8380958377610 0x40b178 [0x1b0]: PERF_RECORD_SAMPLE(IP, 0x2): 7952/7952: 0x4f851a period: 48973 addr: 0 ... branch stack: nr:16 ..... 0: 00000000004b52fd -> 00000000004f82c0 0 cycles P 0 NON_SPEC_CORRECT_PATH ..... 1: ffffffff8220137c -> 00000000004b52f0 0 cycles M 0 NON_SPEC_CORRECT_PATH ..... 2: 000000000041d1c4 -> 00000000004b52f0 0 cycles P 0 NON_SPEC_CORRECT_PATH ..... 3: 00000000004e7ead -> 000000000041d1b0 0 cycles M 0 NON_SPEC_CORRECT_PATH ..... 4: 00000000004e7f91 -> 00000000004e7ead 0 cycles P 0 NON_SPEC_CORRECT_PATH ..... 5: 00000000004e7ea8 -> 00000000004e7f70 0 cycles P 0 NON_SPEC_CORRECT_PATH ..... 6: 00000000004e7e52 -> 00000000004e7e98 0 cycles M 0 SPEC_CORRECT_PATH ..... 7: 00000000004e7e1f -> 00000000004e7e40 0 cycles M 0 NON_SPEC_CORRECT_PATH ..... 8: 00000000004e7f60 -> 00000000004e7df0 0 cycles P 0 NON_SPEC_CORRECT_PATH ..... 9: 00000000004e7f58 -> 00000000004e7f60 0 cycles M 0 NON_SPEC_CORRECT_PATH ..... 10: 000000000041d85d -> 00000000004e7f50 0 cycles P 0 NON_SPEC_CORRECT_PATH ..... 11: 000000000043306a -> 000000000041d840 0 cycles P 0 NON_SPEC_CORRECT_PATH ..... 12: ffffffff8220137c -> 0000000000433040 0 cycles M 0 NON_SPEC_CORRECT_PATH ..... 13: 000000000041e4a1 -> 0000000000433040 0 cycles P 0 NON_SPEC_CORRECT_PATH ..... 14: ffffffff8220137c -> 000000000041e490 0 cycles M 0 NON_SPEC_CORRECT_PATH ..... 15: 000000000041d89b -> 000000000041e487 0 cycles P 0 NON_SPEC_CORRECT_PATH ... thread: test_branch:7952 ...... dso: /data/sandipan/test_branch [...] With the addition of new branch flags, the "brstacksym" fields in perf script output now shows speculation information after the branch type. Change the regular expressions accordingly for the test to pass. Since branch speculation information may vary across platforms, the test does not look for specific values. E.g. $ perf test -v 110 Before: 110: Check branch stack sampling : --- start --- test child forked, pid 54154 Testing user branch stack sampling + grep -E -m1 ^brstack_bench\+[^ ]*/brstack_foo\+[^ ]*/IND_CALL$ /tmp/__perf_test.program.AfhUI/perf.script + cleanup + rm -rf /tmp/__perf_test.program.AfhUI test child finished with -1 ---- end ---- Check branch stack sampling: FAILED! After: 110: Check branch stack sampling : --- start --- test child forked, pid 43716 Testing user branch stack sampling + grep -E -m1 ^brstack_bench\+[^ ]*/brstack_foo\+[^ ]*/IND_CALL/.*$ /tmp/__perf_test.program.xgzAi/perf.script brstack_bench+0x66/brstack_foo+0x0/P/-/-/0/IND_CALL/NON_SPEC_CORRECT_PATH + grep -E -m1 ^brstack_foo\+[^ ]*/brstack_bar\+[^ ]*/CALL/.*$ /tmp/__perf_test.program.xgzAi/perf.script brstack_foo+0x1b/brstack_bar+0x0/P/-/-/0/CALL/NON_SPEC_CORRECT_PATH + grep -E -m1 ^brstack_bench\+[^ ]*/brstack_foo\+[^ ]*/CALL/.*$ /tmp/__perf_test.program.xgzAi/perf.script brstack_bench+0x58/brstack_foo+0x0/P/-/-/0/CALL/NON_SPEC_CORRECT_PATH + grep -E -m1 ^brstack_bench\+[^ ]*/brstack_bar\+[^ ]*/CALL/.*$ /tmp/__perf_test.program.xgzAi/perf.script brstack_bench+0x5d/brstack_bar+0x0/P/-/-/0/CALL/NON_SPEC_CORRECT_PATH + grep -E -m1 ^brstack_bar\+[^ ]*/brstack_foo\+[^ ]*/RET/.*$ /tmp/__perf_test.program.xgzAi/perf.script brstack_bar+0x31/brstack_foo+0x20/P/-/-/0/RET/NON_SPEC_CORRECT_PATH + grep -E -m1 ^brstack_foo\+[^ ]*/brstack_bench\+[^ ]*/RET/.*$ /tmp/__perf_test.program.xgzAi/perf.script brstack_foo+0x36/brstack_bench+0x5d/P/-/-/0/RET/NON_SPEC_CORRECT_PATH + grep -E -m1 ^brstack_bench\+[^ ]*/brstack_bench\+[^ ]*/COND/.*$ /tmp/__perf_test.program.xgzAi/perf.script brstack_bench+0x76/brstack_bench+0x7d/P/-/-/0/COND/NON_SPEC_CORRECT_PATH + grep -E -m1 ^brstack\+[^ ]*/brstack\+[^ ]*/UNCOND/.*$ /tmp/__perf_test.program.xgzAi/perf.script brstack+0x5a/brstack+0x41/P/-/-/0/UNCOND/NON_SPEC_CORRECT_PATH + set +x Testing branch stack filtering permutation (any_call,CALL|IND_CALL|COND_CALL|SYSCALL|IRQ) Testing branch stack filtering permutation (call,CALL|SYSCALL) Testing branch stack filtering permutation (cond,COND) Testing branch stack filtering permutation (any_ret,RET|COND_RET|SYSRET|ERET) Testing branch stack filtering permutation (call,cond,CALL|SYSCALL|COND) Testing branch stack filtering permutation (any_call,cond,CALL|IND_CALL|COND_CALL|IRQ|SYSCALL|COND) Testing branch stack filtering permutation (cond,any_call,any_ret,COND|CALL|IND_CALL|COND_CALL|SYSCALL|IRQ|RET|COND_RET|SYSRET|ERET) test child finished with 0 ---- end ---- Check branch stack sampling: Ok Signed-off-by: Sandipan Das Cc: Alexander Shishkin Cc: Ananth Narayan Cc: Borislav Petkov Cc: Dave Hansen Cc: Ian Rogers Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kajol Jain Cc: Madhavan Srinivasan Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Santosh Shukla Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Thomas Richter Cc: x86@kernel.org Link: https://lore.kernel.org/r/048d67c9de3cc8e3dbf19aaa7ff718dec91364c5.1675333809.git.sandipan.das@amd.com Signed-off-by: Arnaldo Carvalho de Melo

perf session: Avoid calling lseek(2) for pipe

2023-02-02T00:31:04+00:00

We should not call lseek(2) for pipes as it won't work. And we already in the proper place to read the data for AUXTRACE. Add the comment like in the PERF_RECORD_HEADER_TRACING_DATA. Reviewed-by: Adrian Hunter Reviewed-by: James Clark Signed-off-by: Namhyung Kim Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Leo Yan Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20230131023350.1903992-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf build: Use libtraceevent from the system

2022-12-14T14:16:12+00:00

Remove the LIBTRACEEVENT_DYNAMIC and LIBTRACEFS_DYNAMIC make command line variables. If libtraceevent isn't installed or NO_LIBTRACEEVENT=1 is passed to the build, don't compile in libtraceevent and libtracefs support. This also disables CONFIG_TRACE that controls "perf trace". CONFIG_LIBTRACEEVENT is used to control enablement in Build/Makefiles, HAVE_LIBTRACEEVENT is used in C code. Without HAVE_LIBTRACEEVENT tracepoints are disabled and as such the commands kmem, kwork, lock, sched and timechart are removed. The majority of commands continue to work including "perf test". Committer notes: Fixed up a tools/perf/util/Build reject and added: #include to tools/perf/util/scripting-engines/trace-event-perl.c. Committer testing: $ rpm -qi libtraceevent-devel Name : libtraceevent-devel Version : 1.5.3 Release : 2.fc36 Architecture: x86_64 Install Date: Mon 25 Jul 2022 03:20:19 PM -03 Group : Unspecified Size : 27728 License : LGPLv2+ and GPLv2+ Signature : RSA/SHA256, Fri 15 Apr 2022 02:11:58 PM -03, Key ID 999f7cbf38ab71f4 Source RPM : libtraceevent-1.5.3-2.fc36.src.rpm Build Date : Fri 15 Apr 2022 10:57:01 AM -03 Build Host : buildvm-x86-05.iad2.fedoraproject.org Packager : Fedora Project Vendor : Fedora Project URL : https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/ Bug URL : https://bugz.fedoraproject.org/libtraceevent Summary : Development headers of libtraceevent Description : Development headers of libtraceevent-libs $ Default build: $ ldd ~/bin/perf | grep tracee libtraceevent.so.1 => /lib64/libtraceevent.so.1 (0x00007f1dcaf8f000) $ # perf trace -e sched:* --max-events 10 0.000 migration/0/17 sched:sched_migrate_task(comm: "", pid: 1603763 (perf), prio: 120, dest_cpu: 1) 0.005 migration/0/17 sched:sched_wake_idle_without_ipi(cpu: 1) 0.011 migration/0/17 sched:sched_switch(prev_comm: "", prev_pid: 17 (migration/0), prev_state: 1, next_comm: "", next_prio: 120) 1.173 :0/0 sched:sched_wakeup(comm: "", pid: 3138 (gnome-terminal-), prio: 120) 1.180 :0/0 sched:sched_switch(prev_comm: "", prev_prio: 120, next_comm: "", next_pid: 3138 (gnome-terminal-), next_prio: 120) 0.156 migration/1/21 sched:sched_migrate_task(comm: "", pid: 1603763 (perf), prio: 120, orig_cpu: 1, dest_cpu: 2) 0.160 migration/1/21 sched:sched_wake_idle_without_ipi(cpu: 2) 0.166 migration/1/21 sched:sched_switch(prev_comm: "", prev_pid: 21 (migration/1), prev_state: 1, next_comm: "", next_prio: 120) 1.183 :0/0 sched:sched_wakeup(comm: "", pid: 1602985 (kworker/u16:0-f), prio: 120, target_cpu: 1) 1.186 :0/0 sched:sched_switch(prev_comm: "", prev_prio: 120, next_comm: "", next_pid: 1602985 (kworker/u16:0-f), next_prio: 120) # Had to tweak tools/perf/util/setup.py to make sure the python binding shared object links with libtraceevent if -DHAVE_LIBTRACEEVENT is present in CFLAGS. Building with NO_LIBTRACEEVENT=1 uncovered some more build failures: - Make building of data-convert-bt.c to CONFIG_LIBTRACEEVENT=y - perf-$(CONFIG_LIBTRACEEVENT) += scripts/ - bpf_kwork.o needs also to be dependent on CONFIG_LIBTRACEEVENT=y - The python binding needed some fixups and util/trace-event.c can't be built and linked with the python binding shared object, so remove it in tools/perf/util/setup.py and exclude it from the list of dependencies in the python/perf.so Makefile.perf target. Building without libtraceevent-devel installed uncovered more build failures: - The python binding tools/perf/util/python.c was assuming that traceevent/parse-events.h was always available, which was the case when we defaulted to using the in-kernel tools/lib/traceevent/ files, now we need to enclose it under ifdef HAVE_LIBTRACEEVENT, just like the other parts of it that deal with tracepoints. - We have to ifdef the rules in the Build files with CONFIG_LIBTRACEEVENT=y to build builtin-trace.c and tools/perf/trace/beauty/ as we only ifdef setting CONFIG_TRACE=y when setting NO_LIBTRACEEVENT=1 in the make command line, not when we don't detect libtraceevent-devel installed in the system. Simplification here to avoid these two ways of disabling builtin-trace.c and not having CONFIG_TRACE=y when libtraceevent-devel isn't installed is the clean way. From Athira: tools/perf/arch/powerpc/util/Build -perf-y += kvm-stat.o +perf-$(CONFIG_LIBTRACEEVENT) += kvm-stat.o Then, ditto for arm64 and s390, detected by container cross build tests. - s/390 uses test__checkevent_tracepoint() that is now only available if HAVE_LIBTRACEEVENT is defined, enclose the callsite with ifder HAVE_LIBTRACEEVENT. Also from Athira: With this change, I could successfully compile in these environment: - Without libtraceevent-devel installed - With libtraceevent-devel installed - With “make NO_LIBTRACEEVENT=1” Then, finally rename CONFIG_TRACEEVENT to CONFIG_LIBTRACEEVENT for consistency with other libraries detected in tools/perf/. Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Tested-by: Athira Rajeev Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Nick Desaulniers Cc: Peter Zijlstra Cc: Stephane Eranian Cc: bpf@vger.kernel.org Link: http://lore.kernel.org/lkml/20221205225940.3079667-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Use dedicated non-atomic clear/set bit helpers

2022-12-05T12:29:06+00:00

Use the dedicated non-atomic helpers for {clear,set}_bit() and their test variants, i.e. the double-underscore versions. Depsite being defined in atomic.h, and despite the kernel versions being atomic in the kernel, tools' {clear,set}_bit() helpers aren't actually atomic. Move to the double-underscore versions so that the versions that are expected to be atomic (for kernel developers) can be made atomic without affecting users that don't want atomic operations. No functional change intended. Signed-off-by: Sean Christopherson Acked-by: Namhyung Kim Cc: Alexander Shishkin Cc: Andy Shevchenko Cc: James Morse Cc: Jiri Olsa Cc: Marc Zyngier Cc: Mark Rutland Cc: Oliver Upton Cc: Paolo Bonzini Cc: Peter Zijlstra Cc: Rasmus Villemoes Cc: Sean Christopherson Cc: Suzuki Poulouse Cc: Yury Norov Cc: alexandru elisei Cc: kvm@vger.kernel.org Cc: kvmarm@lists.cs.columbia.edu Cc: kvmarm@lists.linux.dev Cc: linux-arm-kernel@lists.infradead.org Link: http://lore.kernel.org/lkml/20221119013450.2643007-6-seanjc@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf session: Change type to avoid undefined behaviour in a signal handler

2022-11-03T12:36:32+00:00

The 'session_done' variable is written to inside the signal handler of 'perf report' and 'perf script'. Switch its type to avoid undefined behavior. Signed-off-by: Ian Rogers Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexey Bayduraev Cc: German Gomez Cc: Ingo Molnar Cc: Jiri Olsa Cc: Leo Yan Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20221024181913.630986-6-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf cpumap: Add range data encoding

2022-10-04T11:55:21+00:00

Often cpumaps encode a range of all CPUs, add a compact encoding that doesn't require a bit mask or list of all CPUs. Signed-off-by: Ian Rogers Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexey Bayduraev Cc: Athira Jajeev Cc: Colin Ian King Cc: Dave Marchevsky Cc: German Gomez Cc: Gustavo A. R. Silva Cc: Ingo Molnar Cc: James Clark Cc: Kees Kook Cc: Leo Yan Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Riccardo Mancini Cc: Song Liu Cc: Stephane Eranian Link: https://lore.kernel.org/r/20220614143353.1559597-7-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf branch: Extend branch type classification

2022-10-04T11:55:20+00:00

This updates the perf tool with generic branch type classification with new ABI extender place holder i.e PERF_BR_EXTEND_ABI, the new 4 bit branch type field i.e perf_branch_entry.new_type, new generic page fault related branch types and some arch specific branch types as added earlier in the kernel. Committer note: Add an extra entry to the branch_type_name array to cope with PERF_BR_EXTEND_ABI, to address build warnings on some compiler/systems, like: 75 8.89 ubuntu:20.04-x-powerpc64el : FAIL gcc version 10.3.0 (Ubuntu 10.3.0-1ubuntu1~20.04) inlined from 'branch_type_stat_display' at util/branch.c:152:4: /usr/powerpc64le-linux-gnu/include/bits/stdio2.h:100:10: error: '%8s' directive argument is null [-Werror=format-overflow=] 100 | return __fprintf_chk (__stream, __USE_FORTIFY_LEVEL - 1, __fmt, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 101 | __va_arg_pack ()); | ~~~~~~~~~~~~~~~~~ Signed-off-by: Anshuman Khandual Cc: Alexander Shishkin Cc: Catalin Marinas Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Robin Murphy Cc: Stephen Rothwell Cc: Suzuki Poulouse Cc: Thomas Gleixner Cc: Will Deacon Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20220824044822.70230-7-anshuman.khandual@arm.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Support reading PERF_FORMAT_LOST

2022-08-19T18:56:56+00:00

The recent kernel added lost count can be read from either read(2) or ring buffer data with PERF_SAMPLE_READ. As it's a variable length data we need to access it according to the format info. But for perf tools use cases, PERF_FORMAT_ID is always set. So we can only check PERF_FORMAT_LOST bit to determine the data format. Add sample_read_value_size() and next_sample_read_value() helpers to make it a bit easier to access. Use them in all places where it reads the struct sample_read_value. Signed-off-by: Namhyung Kim Acked-by: Jiri Olsa Cc: Ian Rogers Cc: Ingo Molnar Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20220819003644.508916-5-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf cpumap: Fix alignment for masks in event encoding

2022-08-19T18:30:28+00:00

A mask encoding of a cpu map is laid out as: u16 nr u16 long_size unsigned long mask[]; However, the mask may be 8-byte aligned meaning there is a 4-byte pad after long_size. This means 32-bit and 64-bit builds see the mask as being at different offsets. On top of this the structure is in the byte data[] encoded as: u16 type char data[] This means the mask's struct isn't the required 4 or 8 byte aligned, but is offset by 2. Consequently the long reads and writes are causing undefined behavior as the alignment is broken. Fix the mask struct by creating explicit 32 and 64-bit variants, use a union to avoid data[] and casts; the struct must be packed so the layout matches the existing perf.data layout. Taking an address of a member of a packed struct breaks alignment so pass the packed perf_record_cpu_map_data to functions, so they can access variables with the right alignment. As the 64-bit version has 4 bytes of padding, optimizing writing to only write the 32-bit version. Committer notes: Disable warnings about 'packed' that break the build in some arches like riscv64, but just around that specific struct. Signed-off-by: Ian Rogers Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexey Bayduraev Cc: Athira Jajeev Cc: Colin Ian King Cc: Dave Marchevsky Cc: German Gomez Cc: Gustavo A. R. Silva Cc: Ingo Molnar Cc: James Clark Cc: Kees Kook Cc: Leo Yan Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Riccardo Mancini Cc: Song Liu Cc: Stephane Eranian Link: https://lore.kernel.org/r/20220614143353.1559597-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Automatically use guest kcore_dir if present

2022-07-20T14:08:37+00:00

When registering a guest machine using machine_pid from the id index, check perf.data for a matching kcore_dir subdirectory and set the kallsyms file name accordingly. If set, use it to find the machine's kernel symbols and object code (from kcore). Signed-off-by: Adrian Hunter Cc: Andi Kleen Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Cc: kvm@vger.kernel.org Link: https://lore.kernel.org/r/20220711093218.10967-23-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo