+ mm-vmscan-add-cgroup-ids-to-vmscan-tracepoints.patch added to mm-new branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm: vmscan: add cgroup IDs to vmscan tracepoints
has been added to the -mm mm-new branch.  Its filename is
     mm-vmscan-add-cgroup-ids-to-vmscan-tracepoints.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmscan-add-cgroup-ids-to-vmscan-tracepoints.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

The mm-new branch of mm.git is not included in linux-next

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------------------------------------------------------
From: Thomas Ballasi <tballasi@linux.microsoft.com>
Subject: mm: vmscan: add cgroup IDs to vmscan tracepoints
Date: Mon, 5 Jan 2026 08:04:22 -0800

Memory reclaim events are currently difficult to attribute to specific
cgroups, making debugging memory pressure issues challenging.  This patch
adds memory cgroup ID (memcg_id) to key vmscan tracepoints to enable
better correlation and analysis.

For operations not associated with a specific cgroup, the field is
defaulted to 0.

Link: https://lkml.kernel.org/r/20260105160423.23708-1-tballasi@linux.microsoft.com
Link: https://lkml.kernel.org/r/20260105160423.23708-2-tballasi@linux.microsoft.com
Signed-off-by: Thomas Ballasi <tballasi@linux.microsoft.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/trace/events/vmscan.h |   79 ++++++++++++++++++--------------
 mm/shrinker.c                 |    2 
 mm/vmscan.c                   |   17 +++---
 3 files changed, 56 insertions(+), 42 deletions(-)

--- a/include/trace/events/vmscan.h~mm-vmscan-add-cgroup-ids-to-vmscan-tracepoints
+++ a/include/trace/events/vmscan.h
@@ -114,85 +114,92 @@ TRACE_EVENT(mm_vmscan_wakeup_kswapd,
 
 DECLARE_EVENT_CLASS(mm_vmscan_direct_reclaim_begin_template,
 
-	TP_PROTO(int order, gfp_t gfp_flags),
+	TP_PROTO(gfp_t gfp_flags, int order, unsigned short memcg_id),
 
-	TP_ARGS(order, gfp_flags),
+	TP_ARGS(gfp_flags, order, memcg_id),
 
 	TP_STRUCT__entry(
-		__field(	int,	order		)
 		__field(	unsigned long,	gfp_flags	)
+		__field(	int,	order		)
+		__field(	unsigned short,	memcg_id	)
 	),
 
 	TP_fast_assign(
-		__entry->order		= order;
 		__entry->gfp_flags	= (__force unsigned long)gfp_flags;
+		__entry->order		= order;
+		__entry->memcg_id	= memcg_id;
 	),
 
-	TP_printk("order=%d gfp_flags=%s",
+	TP_printk("order=%d gfp_flags=%s memcg_id=%u",
 		__entry->order,
-		show_gfp_flags(__entry->gfp_flags))
+		show_gfp_flags(__entry->gfp_flags),
+		__entry->memcg_id)
 );
 
 DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_direct_reclaim_begin,
 
-	TP_PROTO(int order, gfp_t gfp_flags),
+	TP_PROTO(gfp_t gfp_flags, int order, unsigned short memcg_id),
 
-	TP_ARGS(order, gfp_flags)
+	TP_ARGS(gfp_flags, order, memcg_id)
 );
 
 #ifdef CONFIG_MEMCG
 DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_memcg_reclaim_begin,
 
-	TP_PROTO(int order, gfp_t gfp_flags),
+	TP_PROTO(gfp_t gfp_flags, int order, unsigned short memcg_id),
 
-	TP_ARGS(order, gfp_flags)
+	TP_ARGS(gfp_flags, order, memcg_id)
 );
 
 DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_memcg_softlimit_reclaim_begin,
 
-	TP_PROTO(int order, gfp_t gfp_flags),
+	TP_PROTO(gfp_t gfp_flags, int order, unsigned short memcg_id),
 
-	TP_ARGS(order, gfp_flags)
+	TP_ARGS(gfp_flags, order, memcg_id)
 );
 #endif /* CONFIG_MEMCG */
 
 DECLARE_EVENT_CLASS(mm_vmscan_direct_reclaim_end_template,
 
-	TP_PROTO(unsigned long nr_reclaimed),
+	TP_PROTO(unsigned long nr_reclaimed, unsigned short memcg_id),
 
-	TP_ARGS(nr_reclaimed),
+	TP_ARGS(nr_reclaimed, memcg_id),
 
 	TP_STRUCT__entry(
 		__field(	unsigned long,	nr_reclaimed	)
+		__field(	unsigned short,	memcg_id	)
 	),
 
 	TP_fast_assign(
 		__entry->nr_reclaimed	= nr_reclaimed;
+		__entry->memcg_id	= memcg_id;
 	),
 
-	TP_printk("nr_reclaimed=%lu", __entry->nr_reclaimed)
+	TP_printk("nr_reclaimed=%lu memcg_id=%u",
+		__entry->nr_reclaimed,
+		__entry->memcg_id)
 );
 
 DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_direct_reclaim_end,
 
-	TP_PROTO(unsigned long nr_reclaimed),
+	TP_PROTO(unsigned long nr_reclaimed, unsigned short memcg_id),
 
-	TP_ARGS(nr_reclaimed)
+	TP_ARGS(nr_reclaimed, memcg_id)
 );
 
 #ifdef CONFIG_MEMCG
 DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_memcg_reclaim_end,
 
-	TP_PROTO(unsigned long nr_reclaimed),
+	TP_PROTO(unsigned long nr_reclaimed, unsigned short memcg_id),
 
-	TP_ARGS(nr_reclaimed)
+	TP_ARGS(nr_reclaimed, memcg_id)
 );
 
 DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_memcg_softlimit_reclaim_end,
 
-	TP_PROTO(unsigned long nr_reclaimed),
+	TP_PROTO(unsigned long nr_reclaimed, unsigned short memcg_id),
 
-	TP_ARGS(nr_reclaimed)
+	TP_ARGS(nr_reclaimed, memcg_id)
 );
 #endif /* CONFIG_MEMCG */
 
@@ -208,31 +215,34 @@ TRACE_EVENT(mm_shrink_slab_start,
 	TP_STRUCT__entry(
 		__field(struct shrinker *, shr)
 		__field(void *, shrink)
-		__field(int, nid)
 		__field(long, nr_objects_to_shrink)
 		__field(unsigned long, gfp_flags)
 		__field(unsigned long, cache_items)
 		__field(unsigned long long, delta)
 		__field(unsigned long, total_scan)
 		__field(int, priority)
+		__field(int, nid)
+		__field(unsigned short, memcg_id)
 	),
 
 	TP_fast_assign(
 		__entry->shr = shr;
 		__entry->shrink = shr->scan_objects;
-		__entry->nid = sc->nid;
 		__entry->nr_objects_to_shrink = nr_objects_to_shrink;
 		__entry->gfp_flags = (__force unsigned long)sc->gfp_mask;
 		__entry->cache_items = cache_items;
 		__entry->delta = delta;
 		__entry->total_scan = total_scan;
 		__entry->priority = priority;
+		__entry->nid = sc->nid;
+		__entry->memcg_id = sc->memcg ? cgroup_id(sc->memcg->css.cgroup) : 0;
 	),
 
-	TP_printk("%pS %p: nid: %d objects to shrink %ld gfp_flags %s cache items %ld delta %lld total_scan %ld priority %d",
+	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",
 		__entry->shrink,
 		__entry->shr,
 		__entry->nid,
+		__entry->memcg_id,
 		__entry->nr_objects_to_shrink,
 		show_gfp_flags(__entry->gfp_flags),
 		__entry->cache_items,
@@ -242,36 +252,39 @@ TRACE_EVENT(mm_shrink_slab_start,
 );
 
 TRACE_EVENT(mm_shrink_slab_end,
-	TP_PROTO(struct shrinker *shr, int nid, int shrinker_retval,
+	TP_PROTO(struct shrinker *shr, struct shrink_control *sc, int shrinker_retval,
 		long unused_scan_cnt, long new_scan_cnt, long total_scan),
 
-	TP_ARGS(shr, nid, shrinker_retval, unused_scan_cnt, new_scan_cnt,
+	TP_ARGS(shr, sc, shrinker_retval, unused_scan_cnt, new_scan_cnt,
 		total_scan),
 
 	TP_STRUCT__entry(
 		__field(struct shrinker *, shr)
-		__field(int, nid)
 		__field(void *, shrink)
 		__field(long, unused_scan)
 		__field(long, new_scan)
-		__field(int, retval)
 		__field(long, total_scan)
+		__field(int, nid)
+		__field(int, retval)
+		__field(unsigned short, memcg_id)
 	),
 
 	TP_fast_assign(
 		__entry->shr = shr;
-		__entry->nid = nid;
 		__entry->shrink = shr->scan_objects;
 		__entry->unused_scan = unused_scan_cnt;
 		__entry->new_scan = new_scan_cnt;
-		__entry->retval = shrinker_retval;
 		__entry->total_scan = total_scan;
+		__entry->nid = sc->nid;
+		__entry->retval = shrinker_retval;
+		__entry->memcg_id = cgroup_id(sc->memcg->css.cgroup);
 	),
 
-	TP_printk("%pS %p: nid: %d unused scan count %ld new scan count %ld total_scan %ld last shrinker return val %d",
+	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",
 		__entry->shrink,
 		__entry->shr,
 		__entry->nid,
+		__entry->memcg_id,
 		__entry->unused_scan,
 		__entry->new_scan,
 		__entry->total_scan,
@@ -504,9 +517,9 @@ TRACE_EVENT(mm_vmscan_node_reclaim_begin
 
 DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_node_reclaim_end,
 
-	TP_PROTO(unsigned long nr_reclaimed),
+	TP_PROTO(unsigned long nr_reclaimed, unsigned short memcg_id),
 
-	TP_ARGS(nr_reclaimed)
+	TP_ARGS(nr_reclaimed, memcg_id)
 );
 
 TRACE_EVENT(mm_vmscan_throttled,
--- a/mm/shrinker.c~mm-vmscan-add-cgroup-ids-to-vmscan-tracepoints
+++ a/mm/shrinker.c
@@ -461,7 +461,7 @@ static unsigned long do_shrink_slab(stru
 	 */
 	new_nr = add_nr_deferred(next_deferred, shrinker, shrinkctl);
 
-	trace_mm_shrink_slab_end(shrinker, shrinkctl->nid, freed, nr, new_nr, total_scan);
+	trace_mm_shrink_slab_end(shrinker, shrinkctl, freed, nr, new_nr, total_scan);
 	return freed;
 }
 
--- a/mm/vmscan.c~mm-vmscan-add-cgroup-ids-to-vmscan-tracepoints
+++ a/mm/vmscan.c
@@ -6619,11 +6619,11 @@ unsigned long try_to_free_pages(struct z
 		return 1;
 
 	set_task_reclaim_state(current, &sc.reclaim_state);
-	trace_mm_vmscan_direct_reclaim_begin(order, sc.gfp_mask);
+	trace_mm_vmscan_direct_reclaim_begin(sc.gfp_mask, order, 0);
 
 	nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
 
-	trace_mm_vmscan_direct_reclaim_end(nr_reclaimed);
+	trace_mm_vmscan_direct_reclaim_end(nr_reclaimed, 0);
 	set_task_reclaim_state(current, NULL);
 
 	return nr_reclaimed;
@@ -6652,8 +6652,9 @@ 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(sc.gfp_mask,
+						      sc.order,
+						      cgroup_id(memcg->css.cgroup));
 
 	/*
 	 * NOTE: Although we can get the priority field, using it
@@ -6664,7 +6665,7 @@ unsigned long mem_cgroup_shrink_node(str
 	 */
 	shrink_lruvec(lruvec, &sc);
 
-	trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed);
+	trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed, cgroup_id(memcg->css.cgroup));
 
 	*nr_scanned = sc.nr_scanned;
 
@@ -6700,13 +6701,13 @@ unsigned long try_to_free_mem_cgroup_pag
 	struct zonelist *zonelist = node_zonelist(numa_node_id(), sc.gfp_mask);
 
 	set_task_reclaim_state(current, &sc.reclaim_state);
-	trace_mm_vmscan_memcg_reclaim_begin(0, sc.gfp_mask);
+	trace_mm_vmscan_memcg_reclaim_begin(sc.gfp_mask, 0, cgroup_id(memcg->css.cgroup));
 	noreclaim_flag = memalloc_noreclaim_save();
 
 	nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
 
 	memalloc_noreclaim_restore(noreclaim_flag);
-	trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed);
+	trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed, cgroup_id(memcg->css.cgroup));
 	set_task_reclaim_state(current, NULL);
 
 	return nr_reclaimed;
@@ -7651,7 +7652,7 @@ static unsigned long __node_reclaim(stru
 	delayacct_freepages_end();
 	psi_memstall_leave(&pflags);
 
-	trace_mm_vmscan_node_reclaim_end(sc->nr_reclaimed);
+	trace_mm_vmscan_node_reclaim_end(sc->nr_reclaimed, 0);
 
 	return sc->nr_reclaimed;
 }
_

Patches currently in -mm which might be from tballasi@linux.microsoft.com are

mm-vmscan-add-cgroup-ids-to-vmscan-tracepoints.patch
mm-vmscan-add-pids-to-vmscan-tracepoints.patch