From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755465AbZHJPmE (ORCPT ); Mon, 10 Aug 2009 11:42:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755452AbZHJPmB (ORCPT ); Mon, 10 Aug 2009 11:42:01 -0400 Received: from gir.skynet.ie ([193.1.99.77]:51368 "EHLO gir.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753516AbZHJPl5 (ORCPT ); Mon, 10 Aug 2009 11:41:57 -0400 From: Mel Gorman To: Larry Woodman , Ingo Molnar , Andrew Morton Cc: riel@redhat.com, Peter Zijlstra , Li Ming Chun , LKML , linux-mm@kvack.org, Mel Gorman Subject: [PATCH 1/6] tracing, page-allocator: Add trace events for page allocation and page freeing Date: Mon, 10 Aug 2009 16:41:50 +0100 Message-Id: <1249918915-16061-2-git-send-email-mel@csn.ul.ie> X-Mailer: git-send-email 1.6.3.3 In-Reply-To: <1249918915-16061-1-git-send-email-mel@csn.ul.ie> References: <1249918915-16061-1-git-send-email-mel@csn.ul.ie> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch adds trace events for the allocation and freeing of pages, including the freeing of pagevecs. Using the events, it will be known what struct page and pfns are being allocated and freed and what the call site was in many cases. The page alloc tracepoints be used as an indicator as to whether the workload was heavily dependant on the page allocator or not. You can make a guess based on vmstat but you can't get a per-process breakdown. Depending on the call path, the call_site for page allocation may be __get_free_pages() instead of a useful callsite. Instead of passing down a return address similar to slab debugging, the user should enable the stacktrace and seg-addr options to get a proper stack trace. The pagevec free tracepoint has a different usecase. It can be used to get a idea of how many pages are being dumped off the LRU and whether it is kswapd doing the work or a process doing direct reclaim. Signed-off-by: Mel Gorman Acked-by: Rik van Riel --- include/trace/events/kmem.h | 74 +++++++++++++++++++++++++++++++++++++++++++ mm/page_alloc.c | 7 +++- 2 files changed, 80 insertions(+), 1 deletions(-) diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h index 1493c54..0d358a0 100644 --- a/include/trace/events/kmem.h +++ b/include/trace/events/kmem.h @@ -225,6 +225,80 @@ TRACE_EVENT(kmem_cache_free, TP_printk("call_site=%lx ptr=%p", __entry->call_site, __entry->ptr) ); + +TRACE_EVENT(mm_page_free_direct, + + TP_PROTO(struct page *page, unsigned int order), + + TP_ARGS(page, order), + + TP_STRUCT__entry( + __field( struct page *, page ) + __field( unsigned int, order ) + ), + + TP_fast_assign( + __entry->page = page; + __entry->order = order; + ), + + TP_printk("page=%p pfn=%lu order=%d", + __entry->page, + page_to_pfn(__entry->page), + __entry->order) +); + +TRACE_EVENT(mm_pagevec_free, + + TP_PROTO(struct page *page, int cold), + + TP_ARGS(page, cold), + + TP_STRUCT__entry( + __field( struct page *, page ) + __field( int, cold ) + ), + + TP_fast_assign( + __entry->page = page; + __entry->cold = cold; + ), + + TP_printk("page=%p pfn=%lu order=0 cold=%d", + __entry->page, + page_to_pfn(__entry->page), + __entry->cold) +); + +TRACE_EVENT(mm_page_alloc, + + TP_PROTO(struct page *page, unsigned int order, + gfp_t gfp_flags, int migratetype), + + TP_ARGS(page, order, gfp_flags, migratetype), + + TP_STRUCT__entry( + __field( struct page *, page ) + __field( unsigned int, order ) + __field( gfp_t, gfp_flags ) + __field( int, migratetype ) + ), + + TP_fast_assign( + __entry->page = page; + __entry->order = order; + __entry->gfp_flags = gfp_flags; + __entry->migratetype = migratetype; + ), + + TP_printk("page=%p pfn=%lu order=%d migratetype=%d gfp_flags=%s", + __entry->page, + page_to_pfn(__entry->page), + __entry->order, + __entry->migratetype, + show_gfp_flags(__entry->gfp_flags)) +); + #endif /* _TRACE_KMEM_H */ /* This part must be outside protection */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d052abb..440c439 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1062,6 +1062,7 @@ static void free_hot_cold_page(struct page *page, int cold) void free_hot_page(struct page *page) { + trace_mm_page_free_direct(page, 0); free_hot_cold_page(page, 0); } @@ -1905,6 +1906,7 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, zonelist, high_zoneidx, nodemask, preferred_zone, migratetype); + trace_mm_page_alloc(page, order, gfp_mask, migratetype); return page; } EXPORT_SYMBOL(__alloc_pages_nodemask); @@ -1945,13 +1947,16 @@ void __pagevec_free(struct pagevec *pvec) { int i = pagevec_count(pvec); - while (--i >= 0) + while (--i >= 0) { + trace_mm_pagevec_free(pvec->pages[i], pvec->cold); free_hot_cold_page(pvec->pages[i], pvec->cold); + } } void __free_pages(struct page *page, unsigned int order) { if (put_page_testzero(page)) { + trace_mm_page_free_direct(page, order); if (order == 0) free_hot_page(page); else -- 1.6.3.3