Re: [PATCH 0/5] [GIT PULL] tracing/splice/ringbuffer: updates for tip

[Ingo Molnar <mingo@elte.hu>]

* Steven Rostedt <rostedt@goodmis.org> wrote:

> Ingo,
> 
> I was doing a bit of tracing that was stressing the splice code 
> and I found lots of badness. Mostly, the second patch is the 
> killer, and should most likely go upstream ASAP. The ref counting 
> on the splice page is wrong and is never freed!

ah, this probably explains what i reported some time ago: the 
ftrace-analyzer OOM hang. I've cherry-picked this into 
tracing/urgent as well.

> The rest are fixes to the read side. While debugging the memory 
> leak I pulled out my old logdev and used it to monitor what was 
> happening inside of ftrace (tracing the tracer). I did not like 
> the amount of copying that was happening in splice. This was 
> mainly because splice was faster than the writer (and this was 
> with function tracer running!). I added some enhancements to make 
> the splice code perform a little nicer.
> 
> Here's the logdev patch I was using to trace. As well as adding my 
> lfcnprint statements (similar to trace_printk).
> 
>   http://rostedt.homelinux.com/logdev/logdev-0.6.0-2.6.30-rc1.patch
> 
> Please pull the latest tip/tracing/ftrace-1 tree, which can be 
> found at:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git
> tip/tracing/ftrace-1
> 
> 
> Steven Rostedt (5):
>       tracing: convert ftrace_dump spinlocks to raw
>       tracing: fix ref count in splice pages
>       tracing: only add splice page if entries exist
>       tracing: have splice only copy full pages
>       ring-buffer: fix printk output
> 
> ----
>  kernel/trace/ring_buffer.c |    2 +-
>  kernel/trace/trace.c       |   20 ++++++++++++++------
>  2 files changed, 15 insertions(+), 7 deletions(-)

Pulled, thanks a lot Steve!

	Ingo