The patch titled tracing, page-allocator: add trace events for page allocation and page freeing has been added to the -mm tree. Its filename is tracing-page-allocator-add-trace-events-for-page-allocation-and-page-freeing.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: tracing, page-allocator: add trace events for page allocation and page freeing From: Mel Gorman <mel@xxxxxxxxx> 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 <mel@xxxxxxxxx> Acked-by: Rik van Riel <riel@xxxxxxxxxx> Reviewed-by: Ingo Molnar <mingo@xxxxxxx> Cc: Larry Woodman <lwoodman@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Li Ming Chun <macli@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/trace/events/kmem.h | 74 ++++++++++++++++++++++++++++++++++ mm/page_alloc.c | 7 ++- 2 files changed, 80 insertions(+), 1 deletion(-) diff -puN include/trace/events/kmem.h~tracing-page-allocator-add-trace-events-for-page-allocation-and-page-freeing include/trace/events/kmem.h --- a/include/trace/events/kmem.h~tracing-page-allocator-add-trace-events-for-page-allocation-and-page-freeing +++ a/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 -puN mm/page_alloc.c~tracing-page-allocator-add-trace-events-for-page-allocation-and-page-freeing mm/page_alloc.c --- a/mm/page_alloc.c~tracing-page-allocator-add-trace-events-for-page-allocation-and-page-freeing +++ a/mm/page_alloc.c @@ -1097,6 +1097,7 @@ static void free_hot_cold_page(struct pa void free_hot_page(struct page *page) { + trace_mm_page_free_direct(page, 0); free_hot_cold_page(page, 0); } @@ -1941,6 +1942,7 @@ __alloc_pages_nodemask(gfp_t gfp_mask, u zonelist, high_zoneidx, nodemask, preferred_zone, migratetype); + trace_mm_page_alloc(page, order, gfp_mask, migratetype); return page; } EXPORT_SYMBOL(__alloc_pages_nodemask); @@ -1975,13 +1977,16 @@ 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 _ Patches currently in -mm which might be from mel@xxxxxxxxx are memory-hotplug-update-zone-pcp-at-memory-online.patch memory-hotplug-update-zone-pcp-at-memory-online-fix.patch memory-hotplug-exclude-isolated-page-from-pco-page-alloc.patch memory-hotplug-make-pages-from-movable-zone-always-isolatable.patch memory-hotplug-alloc-page-from-other-node-in-memory-online.patch memory-hotplug-migrate-swap-cache-page.patch hugetlb-balance-freeing-of-huge-pages-across-nodes.patch hugetlb-use-free_pool_huge_page-to-return-unused-surplus-pages.patch hugetlb-use-free_pool_huge_page-to-return-unused-surplus-pages-fix.patch hugetlb-clean-up-and-update-huge-pages-documentation.patch hugetlb-restore-interleaving-of-bootmem-huge-pages.patch mm-clean-up-page_remove_rmap.patch mm-update-alloc_flags-after-oom-killer-has-been-called.patch vmscan-dont-attempt-to-reclaim-anon-page-in-lumpy-reclaim-when-no-swap-space-is-avilable.patch vmscan-move-clearpageactive-from-move_active_pages-to-shrink_active_list.patch vmscan-kill-unnecessary-page-flag-test.patch vmscan-kill-unnecessary-prefetch.patch mm-perform-non-atomic-test-clear-of-pg_mlocked-on-free.patch mm-warn-once-when-a-page-is-freed-with-pg_mlocked-set.patch page-allocator-change-migratetype-for-all-pageblocks-within-a-high-order-page-during-__rmqueue_fallback.patch page-allocator-remove-dead-function-free_cold_page.patch tracing-page-allocator-add-trace-events-for-page-allocation-and-page-freeing.patch tracing-page-allocator-add-trace-events-for-anti-fragmentation-falling-back-to-other-migratetypes.patch tracing-page-allocator-add-trace-event-for-page-traffic-related-to-the-buddy-lists.patch tracing-page-allocator-add-a-postprocessing-script-for-page-allocator-related-ftrace-events.patch tracing-documentation-add-a-document-describing-how-to-do-some-performance-analysis-with-tracepoints.patch tracing-documentation-add-a-document-on-the-kmem-tracepoints.patch add-debugging-aid-for-memory-initialisation-problems.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html