From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759398AbYGPIlO (ORCPT ); Wed, 16 Jul 2008 04:41:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754319AbYGPIk7 (ORCPT ); Wed, 16 Jul 2008 04:40:59 -0400 Received: from casper.infradead.org ([85.118.1.10]:48689 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754240AbYGPIk6 (ORCPT ); Wed, 16 Jul 2008 04:40:58 -0400 Subject: Re: [patch 12/17] LTTng instrumentation - page From: Peter Zijlstra To: Mathieu Desnoyers Cc: akpm@linux-foundation.org, Ingo Molnar , linux-kernel@vger.kernel.org, Masami Hiramatsu , Martin Bligh , "Frank Ch. Eigler" , Hideo AOKI , Takashi Nishiie , Steven Rostedt , Eduard - Gabriel Munteanu In-Reply-To: <20080715222748.646777573@polymtl.ca> References: <20080715222604.331269462@polymtl.ca> <20080715222748.646777573@polymtl.ca> Content-Type: text/plain Date: Wed, 16 Jul 2008 10:41:07 +0200 Message-Id: <1216197667.5232.30.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.22.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2008-07-15 at 18:26 -0400, Mathieu Desnoyers wrote: > plain text document attachment (lttng-instrumentation-page.patch) > Paging activity instrumentation. Instruments page allocation/free to keep track > of page allocation. This does not cover hugetlb activity, which is covered by a > separate patch. > > Those tracepoints are used by LTTng. > > About the performance impact of tracepoints (which is comparable to markers), > even without immediate values optimizations, tests done by Hideo Aoki on ia64 > show no regression. His test case was using hackbench on a kernel where > scheduler instrumentation (about 5 events in code scheduler code) was added. > See the "Tracepoints" patch header for performance result detail. > > Signed-off-by: Mathieu Desnoyers > CC: Martin Bligh > CC: Masami Hiramatsu > CC: 'Peter Zijlstra' > CC: "Frank Ch. Eigler" > CC: 'Ingo Molnar' > CC: 'Hideo AOKI' > CC: Takashi Nishiie > CC: 'Steven Rostedt' > CC: Eduard - Gabriel Munteanu > --- > include/trace/page.h | 16 ++++++++++++++++ > mm/page_alloc.c | 6 ++++++ > 2 files changed, 22 insertions(+) > > Index: linux-2.6-lttng/mm/page_alloc.c > =================================================================== > --- linux-2.6-lttng.orig/mm/page_alloc.c 2008-07-15 13:54:46.000000000 -0400 > +++ linux-2.6-lttng/mm/page_alloc.c 2008-07-15 14:04:38.000000000 -0400 > @@ -46,6 +46,7 @@ > #include > #include > #include > +#include > > #include > #include > @@ -510,6 +511,8 @@ static void __free_pages_ok(struct page > int i; > int reserved = 0; > > + trace_page_free(page, order); > + > for (i = 0 ; i < (1 << order) ; ++i) > reserved += free_pages_check(page + i); > if (reserved) > @@ -966,6 +969,8 @@ static void free_hot_cold_page(struct pa > struct per_cpu_pages *pcp; > unsigned long flags; > > + trace_page_free(page, 0); > + > if (PageAnon(page)) > page->mapping = NULL; > if (free_pages_check(page)) > @@ -1630,6 +1635,7 @@ nopage: > show_mem(); > } > got_pg: > + trace_page_alloc(page, order); > return page; > } > > Index: linux-2.6-lttng/include/trace/page.h > =================================================================== > --- /dev/null 1970-01-01 00:00:00.000000000 +0000 > +++ linux-2.6-lttng/include/trace/page.h 2008-07-15 14:04:38.000000000 -0400 This name seems inconsitent with your other choices. include/traec/page_alloc.h comes to mind > @@ -0,0 +1,16 @@ > +#ifndef _TRACE_PAGE_H > +#define _TRACE_PAGE_H > + > +#include > + > +/* > + * mm_page_alloc : page can be NULL. > + */ > +DEFINE_TRACE(page_alloc, > + TPPROTO(struct page *page, unsigned int order), > + TPARGS(page, order)); > +DEFINE_TRACE(page_free, > + TPPROTO(struct page *page, unsigned int order), > + TPARGS(page, order)); > + > +#endif >