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| author |   Kan Liang <kan.liang@linux.intel.com> | 2020-03-19 13:25:10 -0700 |
|---|---|---|
| committer |   Arnaldo Carvalho de Melo <acme@redhat.com> | 2020-04-18 09:05:01 -0300 |
| commit | 9c6c3f471d85a9b0bcda3ce6fc1e2646685e3f60 (patch) | |
| tree | 56ded07276f2adf4b3f1a0d0d32430bca581d4d2 /tools/perf/util/machine.c | |
| parent | perf thread: Add a knob for LBR stitch approach (diff) | |
| download | linux-dev-9c6c3f471d85a9b0bcda3ce6fc1e2646685e3f60.tar.xz linux-dev-9c6c3f471d85a9b0bcda3ce6fc1e2646685e3f60.zip | |
perf thread: Save previous sample for LBR stitching approach
To retrieve the overwritten LBRs from previous sample for LBR stitching
approach, perf has to save the previous sample.
Only allocate the struct lbr_stitch once, when LBR stitching approach is
enabled and kernel supports hw_idx.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200319202517.23423-11-kan.liang@linux.intel.com
[ Use zalloc()/zfree() for thread->lbr_stitch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/machine.c')
| -rw-r--r-- | tools/perf/util/machine.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index f9d69fce584a..a54ca09a1d00 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -2292,6 +2292,21 @@ static int lbr_callchain_add_lbr_ip(struct thread *thread, return 0; } +static bool alloc_lbr_stitch(struct thread *thread) +{ + if (thread->lbr_stitch) + return true; + + thread->lbr_stitch = zalloc(sizeof(*thread->lbr_stitch)); + if (!thread->lbr_stitch) + goto err; + +err: + pr_warning("Failed to allocate space for stitched LBRs. Disable LBR stitch\n"); + thread->lbr_stitch_enable = false; + return false; +} + /* * Recolve LBR callstack chain sample * Return: @@ -2308,6 +2323,7 @@ static int resolve_lbr_callchain_sample(struct thread *thread, { struct ip_callchain *chain = sample->callchain; int chain_nr = min(max_stack, (int)chain->nr), i; + struct lbr_stitch *lbr_stitch; u64 branch_from = 0; int err; @@ -2320,6 +2336,13 @@ static int resolve_lbr_callchain_sample(struct thread *thread, if (i == chain_nr) return 0; + if (thread->lbr_stitch_enable && !sample->no_hw_idx && + alloc_lbr_stitch(thread)) { + lbr_stitch = thread->lbr_stitch; + + memcpy(&lbr_stitch->prev_sample, sample, sizeof(*sample)); + } + if (callchain_param.order == ORDER_CALLEE) { /* Add kernel ip */ err = lbr_callchain_add_kernel_ip(thread, cursor, sample, |