Re: [RFC][PATCH 2/2] [PATCH 2/2] tracing/slub: Move kmalloctracepoint out of inline code

From: Steven Rostedt
Date: Wed Nov 24 2010 - 20:17:36 EST


On Thu, 2010-11-25 at 09:00 +0800, Li Zefan wrote:
> Cc: Richard Kennedy <richard@xxxxxxxxxxxxxxx>
>
> Steven Rostedt wrote:
> > From: Steven Rostedt <srostedt@xxxxxxxxxx>
> >
> > The tracepoint for kmalloc is in the slub inlined code which causes
> > every instance of kmalloc to have the tracepoint.
> >
> > This patch moves the tracepoint out of the inline code to the
> > slub C file (and to page_alloc), which removes a large number of
> > inlined trace points.
> >
> > objdump -dr vmlinux.slub| grep 'jmpq.*<trace_kmalloc' |wc -l
> > 375
> > objdump -dr vmlinux.slub.patched| grep 'jmpq.*<trace_kmalloc' |wc -l
> > 2
> >
> > This also has a nice impact on size.
> > text data bss dec hex filename
> > 7050424 1961068 2482688 11494180 af6324 vmlinux.slub
> > 6979599 1944620 2482688 11406907 ae0e3b vmlinux.slub.patched
> >
> > Siged-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
>
> See this patch from Richard: :)
>
> http://marc.info/?l=linux-kernel&m=128765337729262&w=2
>
> But he only touched slub.

Hehe, and I forgot about it ;-) I notice the large number of kmalloc
tracepoints while analyzing the jump label code, and wanted to do
something about it.

I also see that Pekka replied saying that he applied it.

Pekka, want to take my first patch?

-- Steve


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