diff options
| author | Alexey Budankov <alexey.budankov@linux.intel.com> | 2018-05-24 17:11:54 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-05-25 08:11:12 +0200 |
| commit | 10b1105004fbd81058383537b67df35cc188ab62 (patch) | |
| tree | 8c05509acc2d41d1a7139352958edebff0ce4f16 /arch/x86/kernel/perf_regs.c | |
| parent | 82489c5fe5f99ca95f708fecae9f2c8aa99398bb (diff) | |
perf/x86: Store user space frame-pointer value on a sample
Store user space frame-pointer value (BP register) into the perf trace
on a sample for a process so the value becomes available when
unwinding call stacks for functions gaining event samples.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/311d4a34-f81b-5535-3385-01427ac73b41@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/perf_regs.c')
| -rw-r--r-- | arch/x86/kernel/perf_regs.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/arch/x86/kernel/perf_regs.c b/arch/x86/kernel/perf_regs.c index e47b2dbbdef3..c06c4c16c6b6 100644 --- a/arch/x86/kernel/perf_regs.c +++ b/arch/x86/kernel/perf_regs.c @@ -151,17 +151,19 @@ void perf_get_regs_user(struct perf_regs *regs_user, regs_user_copy->sp = user_regs->sp; regs_user_copy->cs = user_regs->cs; regs_user_copy->ss = user_regs->ss; - /* - * Most system calls don't save these registers, don't report them. + * Store user space frame-pointer value on sample + * to facilitate stack unwinding for cases when + * user space executable code has such support + * enabled at compile time: */ + regs_user_copy->bp = user_regs->bp; + regs_user_copy->bx = -1; - regs_user_copy->bp = -1; regs_user_copy->r12 = -1; regs_user_copy->r13 = -1; regs_user_copy->r14 = -1; regs_user_copy->r15 = -1; - /* * For this to be at all useful, we need a reasonable guess for * the ABI. Be careful: we're in NMI context, and we're |