From: "H. Peter Anvin" <hpa@linux.intel.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
LKML <linux-kernel@vger.kernel.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>,
Peter Zijlstra <peterz@infradead.org>,
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
Avi Kivity <avi@redhat.com>,
Christoph Hellwig <hch@infradead.org>,
Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [RFC][PATCH] tracepoints: Move the work out of line from hotpath sections
Date: Thu, 09 Aug 2012 16:16:28 -0700 [thread overview]
Message-ID: <502444CC.8030906@linux.intel.com> (raw)
In-Reply-To: <1344551131.6935.90.camel@gandalf.stny.rr.com>
On 08/09/2012 03:25 PM, Steven Rostedt wrote:
>>
>> It might be better to improve gcc to move really cold branches out of
>> line (really, really far away), and use the compiler to do this, rather
>> than to use an extra indirection that adds bloat and complexity to the
>> kernel.
>
> I think modifying gcc is something that can help more than tracing. But
> that's been a pipe dream for such a long time that I've started dreaming
> about winning a gold medal in the Olympics instead. Standing on the
> podium listening to the crowd chanting your name along with your country
> is more fun to dream about than seeing your unlikely code stop becoming
> hurdles for the CPU sprinters.
>
At one point, maybe, but lately we have had a lot more traction from the
gcc developers, giving us features like __fentry__ and asm goto.
-hpa
next prev parent reply other threads:[~2012-08-09 23:16 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-09 20:40 [RFC][PATCH] tracepoints: Move the work out of line from hotpath sections Steven Rostedt
2012-08-09 20:50 ` Mathieu Desnoyers
2012-08-09 22:25 ` Steven Rostedt
2012-08-09 23:16 ` H. Peter Anvin [this message]
2012-08-09 23:54 ` David Daney
2012-08-10 1:41 ` Steven Rostedt
2012-08-10 2:05 ` Mathieu Desnoyers
2012-08-10 3:09 ` Steven Rostedt
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