perf session: Show branch speculation info in raw dump
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 <sandipan.das@amd.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ananth Narayan <ananth.narayan@amd.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.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.ibm.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@amd.com> Cc: Santosh Shukla <santosh.shukla@amd.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Richter <tmricht@linux.ibm.com> Cc: x86@kernel.org Link: https://lore.kernel.org/r/048d67c9de3cc8e3dbf19aaa7ff718dec91364c5.1675333809.git.sandipan.das@amd.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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