It is not well analyzed that when/why compaction start/finish or not. With these new tracepoints, we can know much more about start/finish reason of compaction. I can find following bug with these tracepoint.
http://www.spinics.net/lists/linux-mm/msg81582.html Change from v2: omit alloc_flag, classzone_idx from tracepoint output Signed-off-by: Joonsoo Kim <iamjoonsoo....@lge.com> --- include/linux/compaction.h | 3 ++ include/trace/events/compaction.h | 74 +++++++++++++++++++++++++++++++++++++ mm/compaction.c | 38 +++++++++++++++++-- 3 files changed, 111 insertions(+), 4 deletions(-) diff --git a/include/linux/compaction.h b/include/linux/compaction.h index a9547b6..d82181a 100644 --- a/include/linux/compaction.h +++ b/include/linux/compaction.h @@ -12,6 +12,9 @@ #define COMPACT_PARTIAL 3 /* The full zone was compacted */ #define COMPACT_COMPLETE 4 +/* For more detailed tracepoint output */ +#define COMPACT_NO_SUITABLE_PAGE 5 +#define COMPACT_NOT_SUITABLE_ZONE 6 /* When adding new state, please change compaction_status_string, too */ /* Used to signal whether compaction detected need_sched() or lock contention */ diff --git a/include/trace/events/compaction.h b/include/trace/events/compaction.h index 139020b..d465358 100644 --- a/include/trace/events/compaction.h +++ b/include/trace/events/compaction.h @@ -164,6 +164,80 @@ TRACE_EVENT(mm_compaction_end, compaction_status_string[__entry->status]) ); +TRACE_EVENT(mm_compaction_try_to_compact_pages, + + TP_PROTO( + int order, + gfp_t gfp_mask, + enum migrate_mode mode), + + TP_ARGS(order, gfp_mask, mode), + + TP_STRUCT__entry( + __field(int, order) + __field(gfp_t, gfp_mask) + __field(enum migrate_mode, mode) + ), + + TP_fast_assign( + __entry->order = order; + __entry->gfp_mask = gfp_mask; + __entry->mode = mode; + ), + + TP_printk("order=%d gfp_mask=0x%x mode=%d", + __entry->order, + __entry->gfp_mask, + (int)__entry->mode) +); + +DECLARE_EVENT_CLASS(mm_compaction_suitable_template, + + TP_PROTO(struct zone *zone, + int order, + int ret), + + TP_ARGS(zone, order, ret), + + TP_STRUCT__entry( + __field(int, nid) + __field(char *, name) + __field(int, order) + __field(int, ret) + ), + + TP_fast_assign( + __entry->nid = zone_to_nid(zone); + __entry->name = (char *)zone->name; + __entry->order = order; + __entry->ret = ret; + ), + + TP_printk("node=%d zone=%-8s order=%d ret=%s", + __entry->nid, + __entry->name, + __entry->order, + compaction_status_string[__entry->ret]) +); + +DEFINE_EVENT(mm_compaction_suitable_template, mm_compaction_finished, + + TP_PROTO(struct zone *zone, + int order, + int ret), + + TP_ARGS(zone, order, ret) +); + +DEFINE_EVENT(mm_compaction_suitable_template, mm_compaction_suitable, + + TP_PROTO(struct zone *zone, + int order, + int ret), + + TP_ARGS(zone, order, ret) +); + #endif /* _TRACE_COMPACTION_H */ /* This part must be outside protection */ diff --git a/mm/compaction.c b/mm/compaction.c index be28469..97702a8 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -25,6 +25,8 @@ char *compaction_status_string[] = { "continue", "partial", "complete", + "no_suitable_page", + "not_suitable_zone", }; static inline void count_compact_event(enum vm_event_item item) @@ -1048,7 +1050,7 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone, return cc->nr_migratepages ? ISOLATE_SUCCESS : ISOLATE_NONE; } -static int compact_finished(struct zone *zone, struct compact_control *cc, +static int __compact_finished(struct zone *zone, struct compact_control *cc, const int migratetype) { unsigned int order; @@ -1103,7 +1105,20 @@ static int compact_finished(struct zone *zone, struct compact_control *cc, return COMPACT_PARTIAL; } - return COMPACT_CONTINUE; + return COMPACT_NO_SUITABLE_PAGE; +} + +static int compact_finished(struct zone *zone, struct compact_control *cc, + const int migratetype) +{ + int ret; + + ret = __compact_finished(zone, cc, migratetype); + trace_mm_compaction_finished(zone, cc->order, ret); + if (ret == COMPACT_NO_SUITABLE_PAGE) + ret = COMPACT_CONTINUE; + + return ret; } /* @@ -1113,7 +1128,7 @@ static int compact_finished(struct zone *zone, struct compact_control *cc, * COMPACT_PARTIAL - If the allocation would succeed without compaction * COMPACT_CONTINUE - If compaction should run now */ -unsigned long compaction_suitable(struct zone *zone, int order, +static unsigned long __compaction_suitable(struct zone *zone, int order, int alloc_flags, int classzone_idx) { int fragindex; @@ -1157,11 +1172,24 @@ unsigned long compaction_suitable(struct zone *zone, int order, */ fragindex = fragmentation_index(zone, order); if (fragindex >= 0 && fragindex <= sysctl_extfrag_threshold) - return COMPACT_SKIPPED; + return COMPACT_NOT_SUITABLE_ZONE; return COMPACT_CONTINUE; } +unsigned long compaction_suitable(struct zone *zone, int order, + int alloc_flags, int classzone_idx) +{ + unsigned long ret; + + ret = __compaction_suitable(zone, order, alloc_flags, classzone_idx); + trace_mm_compaction_suitable(zone, order, ret); + if (ret == COMPACT_NOT_SUITABLE_ZONE) + ret = COMPACT_SKIPPED; + + return ret; +} + static int compact_zone(struct zone *zone, struct compact_control *cc) { int ret; @@ -1377,6 +1405,8 @@ unsigned long try_to_compact_pages(struct zonelist *zonelist, if (!order || !may_enter_fs || !may_perform_io) return COMPACT_SKIPPED; + trace_mm_compaction_try_to_compact_pages(order, gfp_mask, mode); + /* Compact each zone in the list */ for_each_zone_zonelist_nodemask(zone, z, zonelist, high_zoneidx, nodemask) { -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
