Can we please get some review of this one? It has been in -mm since May 22, no issues that I've heard of. From: Yafang Shao <laoar.shao@xxxxxxxxx> Subject: mm/vmscan: expose cgroup_ino for memcg reclaim tracepoints We can use the exposed cgroup_ino to trace specified cgroup. For example, step 1, get the inode of the specified cgroup $ ls -di /tmp/cgroupv2/foo step 2, set this inode into tracepoint filter to trace this cgroup only (assume the inode is 11) $ cd /sys/kernel/debug/tracing/events/vmscan/ $ echo 'cgroup_ino == 11' > mm_vmscan_memcg_reclaim_begin/filter $ echo 'cgroup_ino == 11' > mm_vmscan_memcg_reclaim_end/filter The reason I made this change is to trace a specific container. Sometimes there're lots of containers on one host. Some of them are not important at all, so we don't care whether them are under memory pressure. While some of them are important, so we want't to know if these containers are doing memcg reclaim and how long this relaim takes. Without this change, we don't know the memcg reclaim happend in which container. Link: http://lkml.kernel.org/r/1557649528-11676-1-git-send-email-laoar.shao@xxxxxxxxx Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: <shaoyafang@xxxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/trace/events/vmscan.h | 71 ++++++++++++++++++++++++++------ mm/vmscan.c | 18 +++++--- 2 files changed, 72 insertions(+), 17 deletions(-) --- a/include/trace/events/vmscan.h~mm-vmscan-expose-cgroup_ino-for-memcg-reclaim-tracepoints +++ a/include/trace/events/vmscan.h @@ -127,18 +127,43 @@ DEFINE_EVENT(mm_vmscan_direct_reclaim_be ); #ifdef CONFIG_MEMCG -DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_memcg_reclaim_begin, +DECLARE_EVENT_CLASS(mm_vmscan_memcg_reclaim_begin_template, - TP_PROTO(int order, gfp_t gfp_flags), + TP_PROTO(unsigned int cgroup_ino, int order, gfp_t gfp_flags), - TP_ARGS(order, gfp_flags) + TP_ARGS(cgroup_ino, order, gfp_flags), + + TP_STRUCT__entry( + __field(unsigned int, cgroup_ino) + __field(int, order) + __field(gfp_t, gfp_flags) + ), + + TP_fast_assign( + __entry->cgroup_ino = cgroup_ino; + __entry->order = order; + __entry->gfp_flags = gfp_flags; + ), + + TP_printk("cgroup_ino=%u order=%d gfp_flags=%s", + __entry->cgroup_ino, __entry->order, + show_gfp_flags(__entry->gfp_flags)) ); -DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_memcg_softlimit_reclaim_begin, +DEFINE_EVENT(mm_vmscan_memcg_reclaim_begin_template, + mm_vmscan_memcg_reclaim_begin, - TP_PROTO(int order, gfp_t gfp_flags), + TP_PROTO(unsigned int cgroup_ino, int order, gfp_t gfp_flags), - TP_ARGS(order, gfp_flags) + TP_ARGS(cgroup_ino, order, gfp_flags) +); + +DEFINE_EVENT(mm_vmscan_memcg_reclaim_begin_template, + mm_vmscan_memcg_softlimit_reclaim_begin, + + TP_PROTO(unsigned int cgroup_ino, int order, gfp_t gfp_flags), + + TP_ARGS(cgroup_ino, order, gfp_flags) ); #endif /* CONFIG_MEMCG */ @@ -167,18 +192,40 @@ DEFINE_EVENT(mm_vmscan_direct_reclaim_en ); #ifdef CONFIG_MEMCG -DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_memcg_reclaim_end, +DECLARE_EVENT_CLASS(mm_vmscan_memcg_reclaim_end_template, - TP_PROTO(unsigned long nr_reclaimed), + TP_PROTO(unsigned int cgroup_ino, unsigned long nr_reclaimed), - TP_ARGS(nr_reclaimed) + TP_ARGS(cgroup_ino, nr_reclaimed), + + TP_STRUCT__entry( + __field(unsigned int, cgroup_ino) + __field(unsigned long, nr_reclaimed) + ), + + TP_fast_assign( + __entry->cgroup_ino = cgroup_ino; + __entry->nr_reclaimed = nr_reclaimed; + ), + + TP_printk("cgroup_ino=%u nr_reclaimed=%lu", + __entry->cgroup_ino, __entry->nr_reclaimed) ); -DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_memcg_softlimit_reclaim_end, +DEFINE_EVENT(mm_vmscan_memcg_reclaim_end_template, + mm_vmscan_memcg_reclaim_end, - TP_PROTO(unsigned long nr_reclaimed), + TP_PROTO(unsigned int cgroup_ino, unsigned long nr_reclaimed), - TP_ARGS(nr_reclaimed) + TP_ARGS(cgroup_ino, nr_reclaimed) +); + +DEFINE_EVENT(mm_vmscan_memcg_reclaim_end_template, + mm_vmscan_memcg_softlimit_reclaim_end, + + TP_PROTO(unsigned int cgroup_ino, unsigned long nr_reclaimed), + + TP_ARGS(cgroup_ino, nr_reclaimed) ); #endif /* CONFIG_MEMCG */ --- a/mm/vmscan.c~mm-vmscan-expose-cgroup_ino-for-memcg-reclaim-tracepoints +++ a/mm/vmscan.c @@ -3191,8 +3191,10 @@ unsigned long mem_cgroup_shrink_node(str sc.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) | (GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK); - trace_mm_vmscan_memcg_softlimit_reclaim_begin(sc.order, - sc.gfp_mask); + trace_mm_vmscan_memcg_softlimit_reclaim_begin( + cgroup_ino(memcg->css.cgroup), + sc.order, + sc.gfp_mask); /* * NOTE: Although we can get the priority field, using it @@ -3203,7 +3205,9 @@ unsigned long mem_cgroup_shrink_node(str */ shrink_node_memcg(pgdat, memcg, &sc, &lru_pages); - trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed); + trace_mm_vmscan_memcg_softlimit_reclaim_end( + cgroup_ino(memcg->css.cgroup), + sc.nr_reclaimed); *nr_scanned = sc.nr_scanned; return sc.nr_reclaimed; @@ -3241,7 +3245,9 @@ unsigned long try_to_free_mem_cgroup_pag zonelist = &NODE_DATA(nid)->node_zonelists[ZONELIST_FALLBACK]; - trace_mm_vmscan_memcg_reclaim_begin(0, sc.gfp_mask); + trace_mm_vmscan_memcg_reclaim_begin( + cgroup_ino(memcg->css.cgroup), + 0, sc.gfp_mask); psi_memstall_enter(&pflags); noreclaim_flag = memalloc_noreclaim_save(); @@ -3251,7 +3257,9 @@ unsigned long try_to_free_mem_cgroup_pag memalloc_noreclaim_restore(noreclaim_flag); psi_memstall_leave(&pflags); - trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed); + trace_mm_vmscan_memcg_reclaim_end( + cgroup_ino(memcg->css.cgroup), + nr_reclaimed); return nr_reclaimed; } _
