Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c5f927a6 authored by Jed Davis's avatar Jed Davis Committed by Russell King
Browse files

ARM: 7765/1: perf: Record the user-mode PC in the call chain. 



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.

Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarJed Davis <jld@mozilla.com>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent a4780ade

arch/arm/kernel/perf_event.c

+1 −0
Original line number Diff line number Diff line
@@ -569,6 +569,7 @@ 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) &&