From 33906bc5c87b50028364405ec425de9638afc719 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Mon, 9 Aug 2010 17:19:16 -0700 Subject: vmscan: tracing: add trace events for kswapd wakeup, sleeping and direct reclaim Add two trace events for kswapd waking up and going asleep for the purposes of tracking kswapd activity and two trace events for direct reclaim beginning and ending. The information can be used to work out how much time a process or the system is spending on the reclamation of pages and in the case of direct reclaim, how many pages were reclaimed for that process. High frequency triggering of these events could point to memory pressure problems. Signed-off-by: Mel Gorman Acked-by: Rik van Riel Acked-by: Larry Woodman Cc: Dave Chinner Cc: Chris Mason Cc: Nick Piggin Cc: Rik van Riel Cc: Johannes Weiner Cc: Christoph Hellwig Cc: KAMEZAWA Hiroyuki Cc: KOSAKI Motohiro Cc: Andrea Arcangeli Cc: Michael Rubin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/trace/events/gfpflags.h | 37 +++++++++++++ include/trace/events/kmem.h | 38 +------------ include/trace/events/vmscan.h | 115 ++++++++++++++++++++++++++++++++++++++++ mm/vmscan.c | 24 +++++++-- 4 files changed, 173 insertions(+), 41 deletions(-) create mode 100644 include/trace/events/gfpflags.h create mode 100644 include/trace/events/vmscan.h diff --git a/include/trace/events/gfpflags.h b/include/trace/events/gfpflags.h new file mode 100644 index 0000000..e3615c0 --- /dev/null +++ b/include/trace/events/gfpflags.h @@ -0,0 +1,37 @@ +/* + * The order of these masks is important. Matching masks will be seen + * first and the left over flags will end up showing by themselves. + * + * For example, if we have GFP_KERNEL before GFP_USER we wil get: + * + * GFP_KERNEL|GFP_HARDWALL + * + * Thus most bits set go first. + */ +#define show_gfp_flags(flags) \ + (flags) ? __print_flags(flags, "|", \ + {(unsigned long)GFP_HIGHUSER_MOVABLE, "GFP_HIGHUSER_MOVABLE"}, \ + {(unsigned long)GFP_HIGHUSER, "GFP_HIGHUSER"}, \ + {(unsigned long)GFP_USER, "GFP_USER"}, \ + {(unsigned long)GFP_TEMPORARY, "GFP_TEMPORARY"}, \ + {(unsigned long)GFP_KERNEL, "GFP_KERNEL"}, \ + {(unsigned long)GFP_NOFS, "GFP_NOFS"}, \ + {(unsigned long)GFP_ATOMIC, "GFP_ATOMIC"}, \ + {(unsigned long)GFP_NOIO, "GFP_NOIO"}, \ + {(unsigned long)__GFP_HIGH, "GFP_HIGH"}, \ + {(unsigned long)__GFP_WAIT, "GFP_WAIT"}, \ + {(unsigned long)__GFP_IO, "GFP_IO"}, \ + {(unsigned long)__GFP_COLD, "GFP_COLD"}, \ + {(unsigned long)__GFP_NOWARN, "GFP_NOWARN"}, \ + {(unsigned long)__GFP_REPEAT, "GFP_REPEAT"}, \ + {(unsigned long)__GFP_NOFAIL, "GFP_NOFAIL"}, \ + {(unsigned long)__GFP_NORETRY, "GFP_NORETRY"}, \ + {(unsigned long)__GFP_COMP, "GFP_COMP"}, \ + {(unsigned long)__GFP_ZERO, "GFP_ZERO"}, \ + {(unsigned long)__GFP_NOMEMALLOC, "GFP_NOMEMALLOC"}, \ + {(unsigned long)__GFP_HARDWALL, "GFP_HARDWALL"}, \ + {(unsigned long)__GFP_THISNODE, "GFP_THISNODE"}, \ + {(unsigned long)__GFP_RECLAIMABLE, "GFP_RECLAIMABLE"}, \ + {(unsigned long)__GFP_MOVABLE, "GFP_MOVABLE"} \ + ) : "GFP_NOWAIT" + diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h index 3adca0c..a9c87ad 100644 --- a/include/trace/events/kmem.h +++ b/include/trace/events/kmem.h @@ -6,43 +6,7 @@ #include #include - -/* - * The order of these masks is important. Matching masks will be seen - * first and the left over flags will end up showing by themselves. - * - * For example, if we have GFP_KERNEL before GFP_USER we wil get: - * - * GFP_KERNEL|GFP_HARDWALL - * - * Thus most bits set go first. - */ -#define show_gfp_flags(flags) \ - (flags) ? __print_flags(flags, "|", \ - {(unsigned long)GFP_HIGHUSER_MOVABLE, "GFP_HIGHUSER_MOVABLE"}, \ - {(unsigned long)GFP_HIGHUSER, "GFP_HIGHUSER"}, \ - {(unsigned long)GFP_USER, "GFP_USER"}, \ - {(unsigned long)GFP_TEMPORARY, "GFP_TEMPORARY"}, \ - {(unsigned long)GFP_KERNEL, "GFP_KERNEL"}, \ - {(unsigned long)GFP_NOFS, "GFP_NOFS"}, \ - {(unsigned long)GFP_ATOMIC, "GFP_ATOMIC"}, \ - {(unsigned long)GFP_NOIO, "GFP_NOIO"}, \ - {(unsigned long)__GFP_HIGH, "GFP_HIGH"}, \ - {(unsigned long)__GFP_WAIT, "GFP_WAIT"}, \ - {(unsigned long)__GFP_IO, "GFP_IO"}, \ - {(unsigned long)__GFP_COLD, "GFP_COLD"}, \ - {(unsigned long)__GFP_NOWARN, "GFP_NOWARN"}, \ - {(unsigned long)__GFP_REPEAT, "GFP_REPEAT"}, \ - {(unsigned long)__GFP_NOFAIL, "GFP_NOFAIL"}, \ - {(unsigned long)__GFP_NORETRY, "GFP_NORETRY"}, \ - {(unsigned long)__GFP_COMP, "GFP_COMP"}, \ - {(unsigned long)__GFP_ZERO, "GFP_ZERO"}, \ - {(unsigned long)__GFP_NOMEMALLOC, "GFP_NOMEMALLOC"}, \ - {(unsigned long)__GFP_HARDWALL, "GFP_HARDWALL"}, \ - {(unsigned long)__GFP_THISNODE, "GFP_THISNODE"}, \ - {(unsigned long)__GFP_RECLAIMABLE, "GFP_RECLAIMABLE"}, \ - {(unsigned long)__GFP_MOVABLE, "GFP_MOVABLE"} \ - ) : "GFP_NOWAIT" +#include "gfpflags.h" DECLARE_EVENT_CLASS(kmem_alloc, diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h new file mode 100644 index 0000000..f76521f --- /dev/null +++ b/include/trace/events/vmscan.h @@ -0,0 +1,115 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM vmscan + +#if !defined(_TRACE_VMSCAN_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_VMSCAN_H + +#include +#include +#include "gfpflags.h" + +TRACE_EVENT(mm_vmscan_kswapd_sleep, + + TP_PROTO(int nid), + + TP_ARGS(nid), + + TP_STRUCT__entry( + __field( int, nid ) + ), + + TP_fast_assign( + __entry->nid = nid; + ), + + TP_printk("nid=%d", __entry->nid) +); + +TRACE_EVENT(mm_vmscan_kswapd_wake, + + TP_PROTO(int nid, int order), + + TP_ARGS(nid, order), + + TP_STRUCT__entry( + __field( int, nid ) + __field( int, order ) + ), + + TP_fast_assign( + __entry->nid = nid; + __entry->order = order; + ), + + TP_printk("nid=%d order=%d", __entry->nid, __entry->order) +); + +TRACE_EVENT(mm_vmscan_wakeup_kswapd, + + TP_PROTO(int nid, int zid, int order), + + TP_ARGS(nid, zid, order), + + TP_STRUCT__entry( + __field( int, nid ) + __field( int, zid ) + __field( int, order ) + ), + + TP_fast_assign( + __entry->nid = nid; + __entry->zid = zid; + __entry->order = order; + ), + + TP_printk("nid=%d zid=%d order=%d", + __entry->nid, + __entry->zid, + __entry->order) +); + +TRACE_EVENT(mm_vmscan_direct_reclaim_begin, + + TP_PROTO(int order, int may_writepage, gfp_t gfp_flags), + + TP_ARGS(order, may_writepage, gfp_flags), + + TP_STRUCT__entry( + __field( int, order ) + __field( int, may_writepage ) + __field( gfp_t, gfp_flags ) + ), + + TP_fast_assign( + __entry->order = order; + __entry->may_writepage = may_writepage; + __entry->gfp_flags = gfp_flags; + ), + + TP_printk("order=%d may_writepage=%d gfp_flags=%s", + __entry->order, + __entry->may_writepage, + show_gfp_flags(__entry->gfp_flags)) +); + +TRACE_EVENT(mm_vmscan_direct_reclaim_end, + + TP_PROTO(unsigned long nr_reclaimed), + + TP_ARGS(nr_reclaimed), + + TP_STRUCT__entry( + __field( unsigned long, nr_reclaimed ) + ), + + TP_fast_assign( + __entry->nr_reclaimed = nr_reclaimed; + ), + + TP_printk("nr_reclaimed=%lu", __entry->nr_reclaimed) +); + +#endif /* _TRACE_VMSCAN_H */ + +/* This part must be outside protection */ +#include diff --git a/mm/vmscan.c b/mm/vmscan.c index 6dafa45..c99bc41 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -48,6 +48,9 @@ #include "internal.h" +#define CREATE_TRACE_POINTS +#include + struct scan_control { /* Incremented by the number of inactive pages that were scanned */ unsigned long nr_scanned; @@ -1883,6 +1886,7 @@ out: unsigned long try_to_free_pages(struct zonelist *zonelist, int order, gfp_t gfp_mask, nodemask_t *nodemask) { + unsigned long nr_reclaimed; struct scan_control sc = { .gfp_mask = gfp_mask, .may_writepage = !laptop_mode, @@ -1895,7 +1899,15 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order, .nodemask = nodemask, }; - return do_try_to_free_pages(zonelist, &sc); + trace_mm_vmscan_direct_reclaim_begin(order, + sc.may_writepage, + gfp_mask); + + nr_reclaimed = do_try_to_free_pages(zonelist, &sc); + + trace_mm_vmscan_direct_reclaim_end(nr_reclaimed); + + return nr_reclaimed; } #ifdef CONFIG_CGROUP_MEM_RES_CTLR @@ -2294,9 +2306,10 @@ static int kswapd(void *p) * premature sleep. If not, then go fully * to sleep until explicitly woken up */ - if (!sleeping_prematurely(pgdat, order, remaining)) + if (!sleeping_prematurely(pgdat, order, remaining)) { + trace_mm_vmscan_kswapd_sleep(pgdat->node_id); schedule(); - else { + } else { if (remaining) count_vm_event(KSWAPD_LOW_WMARK_HIT_QUICKLY); else @@ -2316,8 +2329,10 @@ static int kswapd(void *p) * We can speed up thawing tasks if we don't call balance_pgdat * after returning from the refrigerator */ - if (!ret) + if (!ret) { + trace_mm_vmscan_kswapd_wake(pgdat->node_id, order); balance_pgdat(pgdat, order); + } } return 0; } @@ -2337,6 +2352,7 @@ void wakeup_kswapd(struct zone *zone, int order) return; if (pgdat->kswapd_max_order < order) pgdat->kswapd_max_order = order; + trace_mm_vmscan_wakeup_kswapd(pgdat->node_id, zone_idx(zone), order); if (!cpuset_zone_allowed_hardwall(zone, GFP_KERNEL)) return; if (!waitqueue_active(&pgdat->kswapd_wait)) -- cgit v1.1