The changes aims at adding additionnal tracepoints variables to help debuggers attribute them to specific processes.
The PID field uses in_task() to reliably detect when we're in process context and can safely access current->pid. When not in process context (such as in interrupt or in an asynchronous RCU context), the field is set to -1 as a sentinel value. Signed-off-by: Thomas Ballasi <[email protected]> --- include/trace/events/vmscan.h | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h index afc9f80d03f34..eddb4e75e2e23 100644 --- a/include/trace/events/vmscan.h +++ b/include/trace/events/vmscan.h @@ -121,18 +121,21 @@ DECLARE_EVENT_CLASS(mm_vmscan_direct_reclaim_begin_template, TP_STRUCT__entry( __field( int, order ) __field( unsigned long, gfp_flags ) + __field( int, pid ) __field( unsigned short, memcg_id ) ), TP_fast_assign( __entry->order = order; __entry->gfp_flags = (__force unsigned long)gfp_flags; + __entry->pid = in_task() ? current->pid : -1; __entry->memcg_id = memcg_id; ), - TP_printk("order=%d gfp_flags=%s memcg_id=%u", + TP_printk("order=%d gfp_flags=%s pid=%d memcg_id=%u", __entry->order, show_gfp_flags(__entry->gfp_flags), + __entry->pid, __entry->memcg_id) ); @@ -167,16 +170,19 @@ DECLARE_EVENT_CLASS(mm_vmscan_direct_reclaim_end_template, TP_STRUCT__entry( __field( unsigned long, nr_reclaimed ) + __field( int, pid ) __field( unsigned short, memcg_id ) ), TP_fast_assign( __entry->nr_reclaimed = nr_reclaimed; + __entry->pid = in_task() ? current->pid : -1; __entry->memcg_id = memcg_id; ), - TP_printk("nr_reclaimed=%lu memcg_id=%u", + TP_printk("nr_reclaimed=%lu pid=%d memcg_id=%u", __entry->nr_reclaimed, + __entry->pid, __entry->memcg_id) ); @@ -216,6 +222,7 @@ TRACE_EVENT(mm_shrink_slab_start, __field(struct shrinker *, shr) __field(void *, shrink) __field(int, nid) + __field(int, pid) __field(unsigned short, memcg_id) __field(long, nr_objects_to_shrink) __field(unsigned long, gfp_flags) @@ -229,6 +236,7 @@ TRACE_EVENT(mm_shrink_slab_start, __entry->shr = shr; __entry->shrink = shr->scan_objects; __entry->nid = sc->nid; + __entry->pid = in_task() ? current->pid : -1; __entry->memcg_id = sc->memcg ? mem_cgroup_id(sc->memcg) : 0; __entry->nr_objects_to_shrink = nr_objects_to_shrink; __entry->gfp_flags = (__force unsigned long)sc->gfp_mask; @@ -238,10 +246,11 @@ TRACE_EVENT(mm_shrink_slab_start, __entry->priority = priority; ), - TP_printk("%pS %p: nid: %d memcg_id: %u objects to shrink %ld gfp_flags %s cache items %ld delta %lld total_scan %ld priority %d", + TP_printk("%pS %p: nid: %d pid: %d memcg_id: %u objects to shrink %ld gfp_flags %s cache items %ld delta %lld total_scan %ld priority %d", __entry->shrink, __entry->shr, __entry->nid, + __entry->pid, __entry->memcg_id, __entry->nr_objects_to_shrink, show_gfp_flags(__entry->gfp_flags), @@ -261,6 +270,7 @@ TRACE_EVENT(mm_shrink_slab_end, TP_STRUCT__entry( __field(struct shrinker *, shr) __field(int, nid) + __field(int, pid) __field(unsigned short, memcg_id) __field(void *, shrink) __field(long, unused_scan) @@ -272,6 +282,7 @@ TRACE_EVENT(mm_shrink_slab_end, TP_fast_assign( __entry->shr = shr; __entry->nid = sc->nid; + __entry->pid = in_task() ? current->pid : -1; __entry->memcg_id = sc->memcg ? mem_cgroup_id(sc->memcg) : 0; __entry->shrink = shr->scan_objects; __entry->unused_scan = unused_scan_cnt; @@ -280,10 +291,11 @@ TRACE_EVENT(mm_shrink_slab_end, __entry->total_scan = total_scan; ), - TP_printk("%pS %p: nid: %d memcg_id: %u unused scan count %ld new scan count %ld total_scan %ld last shrinker return val %d", + TP_printk("%pS %p: nid: %d pid: %d memcg_id: %u unused scan count %ld new scan count %ld total_scan %ld last shrinker return val %d", __entry->shrink, __entry->shr, __entry->nid, + __entry->pid, __entry->memcg_id, __entry->unused_scan, __entry->new_scan, -- 2.33.8
