Re: [PATCH net-next 1/3] perf: generalize perf_callchain

Peter Zijlstra
2016-02-25T14:19:10Z

On Wed, Feb 17, 2016 at 07:58:57PM -0800, Alexei Starovoitov wrote:
> . avoid walking the stack when there is no room left in the buffer
> . generalize get_perf_callchain() to be called from bpf helper

If it does two things it should be two patches.

> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
> ---
> arch/x86/include/asm/stacktrace.h | 2 +-
> arch/x86/kernel/cpu/perf_event.c | 4 ++--
> arch/x86/kernel/dumpstack.c | 6 ++++--
> arch/x86/kernel/stacktrace.c | 18 +++++++++++-------
> arch/x86/oprofile/backtrace.c | 3 ++-
> include/linux/perf_event.h | 13 +++++++++++--
> kernel/events/callchain.c | 32 ++++++++++++++++++++------------
> kernel/events/internal.h | 2 --
> 8 files changed, 51 insertions(+), 29 deletions(-)

And at the very least this should have had a note that it doesn't break
all the other archs that implement perf-callchain stuff.