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

From: Peter Zijlstra
Date: Thu Feb 25 2016 - 11:45:54 EST


On Thu, Feb 25, 2016 at 08:37:34AM -0800, Alexei Starovoitov wrote:
> On 2/25/16 6:18 AM, Peter Zijlstra wrote:
> >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.
>
> could have been two patches, but it will only add more churn
> to the same lines. what's the concern?

It makes review easier, shows which modification is for what purpose.

Also the changelog really needs more; it should for example explain what
BPF needs from the callchain code, and preferably why.