Slab reclaim works with reclaim priority, which influences how much to reclaim,
but is not directly passed to individual shrinkers. The next patch introduces a
slab shrinker that uses the priority, so add it to shrink_control and
initialize appropriately. We can then also remove the parameter from
shrink_slab() and trace_mm_shrink_slab_start().
Signed-off-by: Vlastimil Babka <vba...@suse.cz>
---
include/linux/shrinker.h | 3 +++
include/trace/events/vmscan.h | 8 +++-----
mm/vmscan.c | 14 ++++++++------
3 files changed, 14 insertions(+), 11 deletions(-)
diff --git a/include/linux/shrinker.h b/include/linux/shrinker.h
index 0f80123650e2..1066f052be4f 100644
--- a/include/linux/shrinker.h
+++ b/include/linux/shrinker.h
@@ -29,6 +29,9 @@ struct shrink_control {
*/
unsigned long nr_scanned;
+ /* current reclaim priority */
+ int priority;
+
/* current memcg being shrunk (for memcg aware shrinkers) */
struct mem_cgroup *memcg;
};
diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index 2070df64958e..d42e480977c6 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -185,11 +185,9 @@ DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template,
mm_vmscan_memcg_softlimit_re
TRACE_EVENT(mm_shrink_slab_start,
TP_PROTO(struct shrinker *shr, struct shrink_control *sc,
long nr_objects_to_shrink, unsigned long cache_items,
- unsigned long long delta, unsigned long total_scan,
- int priority),
+ unsigned long long delta, unsigned long total_scan),
- TP_ARGS(shr, sc, nr_objects_to_shrink, cache_items, delta, total_scan,
- priority),
+ TP_ARGS(shr, sc, nr_objects_to_shrink, cache_items, delta, total_scan),
TP_STRUCT__entry(
__field(struct shrinker *, shr)
@@ -212,7 +210,7 @@ TRACE_EVENT(mm_shrink_slab_start,
__entry->cache_items = cache_items;
__entry->delta = delta;
__entry->total_scan = total_scan;
- __entry->priority = priority;
+ __entry->priority = sc->priority;
),
TP_printk("%pS %p: nid: %d objects to shrink %ld gfp_flags %s cache
items %ld delta %lld total_scan %ld priority %d",
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 469016222cdb..bc5157625cec 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -410,7 +410,7 @@ EXPORT_SYMBOL(unregister_shrinker);
#define SHRINK_BATCH 128
static unsigned long do_shrink_slab(struct shrink_control *shrinkctl,
- struct shrinker *shrinker, int priority)
+ struct shrinker *shrinker)
{
unsigned long freed = 0;
unsigned long long delta;
@@ -439,7 +439,7 @@ static unsigned long do_shrink_slab(struct shrink_control
*shrinkctl,
total_scan = nr;
if (shrinker->seeks) {
- delta = freeable >> priority;
+ delta = freeable >> shrinkctl->priority;
delta *= 4;
do_div(delta, shrinker->seeks);
} else {
@@ -484,7 +484,7 @@ static unsigned long do_shrink_slab(struct shrink_control
*shrinkctl,
total_scan = freeable * 2;
trace_mm_shrink_slab_start(shrinker, shrinkctl, nr,
- freeable, delta, total_scan, priority);
+ freeable, delta, total_scan);
/*
* Normally, we should not scan less than batch_size objects in one
@@ -562,6 +562,7 @@ static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int
nid,
struct shrink_control sc = {
.gfp_mask = gfp_mask,
.nid = nid,
+ .priority = priority,
.memcg = memcg,
};
struct shrinker *shrinker;
@@ -578,7 +579,7 @@ static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int
nid,
!(shrinker->flags & SHRINKER_NONSLAB))
continue;
- ret = do_shrink_slab(&sc, shrinker, priority);
+ ret = do_shrink_slab(&sc, shrinker);
if (ret == SHRINK_EMPTY) {
clear_bit(i, map->map);
/*
@@ -597,7 +598,7 @@ static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int
nid,
* set_bit() do_shrink_slab()
*/
smp_mb__after_atomic();
- ret = do_shrink_slab(&sc, shrinker, priority);
+ ret = do_shrink_slab(&sc, shrinker);
if (ret == SHRINK_EMPTY)
ret = 0;
else
@@ -666,10 +667,11 @@ static unsigned long shrink_slab(gfp_t gfp_mask, int nid,
struct shrink_control sc = {
.gfp_mask = gfp_mask,
.nid = nid,
+ .priority = priority,
.memcg = memcg,
};
- ret = do_shrink_slab(&sc, shrinker, priority);
+ ret = do_shrink_slab(&sc, shrinker);
if (ret == SHRINK_EMPTY)
ret = 0;
freed += ret;
--
2.30.0
