Messages in this thread Patch in this message | | | From | Kamal Mostafa <> | Subject | [PATCH 030/145] ARM: 7765/1: perf: Record the user-mode PC in the call chain. | Date | Wed, 17 Jul 2013 15:46:02 -0700 |
| |
3.8.13.5 -stable review patch. If anyone has any objections, please let me know.
------------------
From: Jed Davis <jld@mozilla.com>
commit c5f927a6f62196226915f12194c9d0df4e2210d7 upstream.
With this change, we no longer lose the innermost entry in the user-mode part of the call chain. See also the x86 port, which includes the ip.
It's possible to partially work around this problem by post-processing the data to use the PERF_SAMPLE_IP value, but this works only if the CPU wasn't in the kernel when the sample was taken.
Signed-off-by: Jed Davis <jld@mozilla.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- arch/arm/kernel/perf_event.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 23fa6a2..5da31bb 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -579,6 +579,7 @@ perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs) return; } + perf_callchain_store(entry, regs->ARM_pc); tail = (struct frame_tail __user *)regs->ARM_fp - 1; while ((entry->nr < PERF_MAX_STACK_DEPTH) && -- 1.8.1.2
| |