From 6ade6c6460357a4878db24f468bbc66e3eddcd42 Mon Sep 17 00:00:00 2001 From: Sandipan Das Date: Thu, 2 Feb 2023 17:56:14 +0530 Subject: perf script: Show branch speculation info Show the branch speculation info if provided by the branch recording hardware feature. This can be useful for optimizing code further. The speculation info is appended to the end of the list of fields so any existing tools that use "/" as a delimiter for access fields via an index remain unaffected. Also show "-" instead of "N/A" when speculation info is unavailable because "/" is used as the field separator. E.g. $ perf record -j any,u,save_type ./test_branch $ perf script --fields brstacksym Before: [...] check_match+0x60/strcmp+0x0/P/-/-/0/CALL do_lookup_x+0x3c5/check_match+0x0/P/-/-/0/CALL [...] After: [...] check_match+0x60/strcmp+0x0/P/-/-/0/CALL/NON_SPEC_CORRECT_PATH do_lookup_x+0x3c5/check_match+0x0/P/-/-/0/CALL/NON_SPEC_CORRECT_PATH [...] The bitfield swapping scheme used duing sample parsing has changed because of the addition of new branch flags, namely "spec", "new_type" and "priv". Earlier, these were all part of the "reserved" field but now, each of these fields get swapped separately. Change the expected flag values accordingly for the test to pass. E.g. $ perf test -v 27 Before: 27: Sample parsing : --- start --- test child forked, pid 61979 parsing failed for sample_type 0x800 test child finished with -1 ---- end ---- Sample parsing: FAILED! After: 27: Sample parsing : --- start --- test child forked, pid 63293 test child finished with 0 ---- end ---- Sample parsing: Ok Signed-off-by: Sandipan Das Tested-by: Arnaldo Carvalho de Melo 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/56e272583552526e999ba0b536ac009ae3613966.1675333809.git.sandipan.das@amd.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-script.c | 5 +++-- tools/perf/tests/sample-parsing.c | 2 +- tools/perf/util/branch.c | 15 +++++++++++++++ tools/perf/util/branch.h | 2 ++ tools/perf/util/evsel.c | 15 ++++++++++++--- 5 files changed, 33 insertions(+), 6 deletions(-) (limited to 'tools') diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c index cb6b34da4eef..339b441015eb 100644 --- a/tools/perf/builtin-script.c +++ b/tools/perf/builtin-script.c @@ -889,12 +889,13 @@ mispred_str(struct branch_entry *br) static int print_bstack_flags(FILE *fp, struct branch_entry *br) { - return fprintf(fp, "/%c/%c/%c/%d/%s ", + return fprintf(fp, "/%c/%c/%c/%d/%s/%s ", mispred_str(br), br->flags.in_tx ? 'X' : '-', br->flags.abort ? 'A' : '-', br->flags.cycles, - get_branch_type(br)); + get_branch_type(br), + br->flags.spec ? branch_spec_desc(br->flags.spec) : "-"); } static int perf_sample__fprintf_brstack(struct perf_sample *sample, diff --git a/tools/perf/tests/sample-parsing.c b/tools/perf/tests/sample-parsing.c index 927c7f0cc4cc..25a3f6cece50 100644 --- a/tools/perf/tests/sample-parsing.c +++ b/tools/perf/tests/sample-parsing.c @@ -37,7 +37,7 @@ * in branch_stack variable. */ #define BS_EXPECTED_BE 0xa000d00000000000 -#define BS_EXPECTED_LE 0xd5000000 +#define BS_EXPECTED_LE 0x1aa00000000 #define FLAG(s) s->branch_stack->entries[i].flags static bool samples_same(const struct perf_sample *s1, diff --git a/tools/perf/util/branch.c b/tools/perf/util/branch.c index 6d38238481d3..378f16a24751 100644 --- a/tools/perf/util/branch.c +++ b/tools/perf/util/branch.c @@ -212,3 +212,18 @@ int branch_type_str(struct branch_type_stat *st, char *bf, int size) return printed; } + +const char *branch_spec_desc(int spec) +{ + const char *branch_spec_outcomes[PERF_BR_SPEC_MAX] = { + "N/A", + "SPEC_WRONG_PATH", + "NON_SPEC_CORRECT_PATH", + "SPEC_CORRECT_PATH", + }; + + if (spec >= 0 && spec < PERF_BR_SPEC_MAX) + return branch_spec_outcomes[spec]; + + return NULL; +} diff --git a/tools/perf/util/branch.h b/tools/perf/util/branch.h index 3ed792db1125..e41bfffe2217 100644 --- a/tools/perf/util/branch.h +++ b/tools/perf/util/branch.h @@ -89,4 +89,6 @@ const char *get_branch_type(struct branch_entry *e); void branch_type_stat_display(FILE *fp, struct branch_type_stat *st); int branch_type_str(struct branch_type_stat *st, char *bf, int bfsize); +const char *branch_spec_desc(int spec); + #endif /* _PERF_BRANCH_H */ diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 8550638587e5..019e53db03b3 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -2319,7 +2319,10 @@ u64 evsel__bitfield_swap_branch_flags(u64 value) * abort:1 //transaction abort * cycles:16 //cycle count to last branch * type:4 //branch type - * reserved:40 + * spec:2 //branch speculation info + * new_type:4 //additional branch type + * priv:3 //privilege level + * reserved:31 * } * } * @@ -2335,7 +2338,10 @@ u64 evsel__bitfield_swap_branch_flags(u64 value) new_val |= bitfield_swap(value, 3, 1); new_val |= bitfield_swap(value, 4, 16); new_val |= bitfield_swap(value, 20, 4); - new_val |= bitfield_swap(value, 24, 40); + new_val |= bitfield_swap(value, 24, 2); + new_val |= bitfield_swap(value, 26, 4); + new_val |= bitfield_swap(value, 30, 3); + new_val |= bitfield_swap(value, 33, 31); } else { new_val = bitfield_swap(value, 63, 1); new_val |= bitfield_swap(value, 62, 1); @@ -2343,7 +2349,10 @@ u64 evsel__bitfield_swap_branch_flags(u64 value) new_val |= bitfield_swap(value, 60, 1); new_val |= bitfield_swap(value, 44, 16); new_val |= bitfield_swap(value, 40, 4); - new_val |= bitfield_swap(value, 0, 40); + new_val |= bitfield_swap(value, 38, 2); + new_val |= bitfield_swap(value, 34, 4); + new_val |= bitfield_swap(value, 31, 3); + new_val |= bitfield_swap(value, 0, 31); } return new_val; -- cgit