Re: [PATCH x86/urgent] bpf: emulate push insns for uprobe on x86

[Yonghong Song]

On 11/8/17 10:53 PM, Thomas Gleixner wrote:
> On Wed, 8 Nov 2017, Yonghong Song wrote:
> > On 11/8/17 4:06 PM, David Miller wrote:
> > > From: Yonghong Song <yhs@xxxxxx>
> > > Date: Wed, 8 Nov 2017 13:37:12 -0800
> > >
> > > > Uprobe is a tracing mechanism for userspace programs.
> > > > Typical uprobe will incur overhead of two traps.
> > > > First trap is caused by replaced trap insn, and
> > > > the second trap is to execute the original displaced
> > > > insn in user space.
> > >    ...
> > >
> > > I don't understand how this is bpf related, and if it is you don't
> > > explain it well in the commit message.
> >
> > Right. This is not related to bpf. Will remove the "bpf" from the subject line
> > in the next revision.
>
> The proper subject is something like:
>
>      [PATCH] uprobes/x86: .......

Thanks, Thomas,

I will fix the subject etc. Previously, I added x86/urgent as the branch
I did my test on top of it (similar to net-next). I will add that 
information in the comments and re-submit.

> which you can figure out by looking at the subsystem prefixes via
>
>      git log arch/x86/kernel/uprobes.c
>
> Note, that it says [PATCH} and nothing else. That patch is a nice
> performance improvement, but certainly not x86/urgent material. x86/urgent
> is for bug and regression fixes.
>
> Thanks,
>
> 	tglx