diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h index d70b53e65f43..e0b8b9173e1c 100644 --- a/include/trace/events/vmscan.h +++ b/include/trace/events/vmscan.h @@ -192,12 +192,12 @@ 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 pgs_scanned, - unsigned long lru_pgs, unsigned long cache_items, - unsigned long long delta, unsigned long total_scan), + long nr_objects_to_shrink, unsigned long cache_items, + unsigned long long delta, unsigned long total_scan, + int priority), - TP_ARGS(shr, sc, nr_objects_to_shrink, pgs_scanned, lru_pgs, - cache_items, delta, total_scan), + TP_ARGS(shr, sc, nr_objects_to_shrink, cache_items, delta, total_scan, + priority), TP_STRUCT__entry( __field(struct shrinker *, shr) @@ -205,11 +205,10 @@ TRACE_EVENT(mm_shrink_slab_start, __field(int, nid) __field(long, nr_objects_to_shrink) __field(gfp_t, gfp_flags) - __field(unsigned long, pgs_scanned) - __field(unsigned long, lru_pgs) __field(unsigned long, cache_items) __field(unsigned long long, delta) __field(unsigned long, total_scan) + __field(int, priority) ), TP_fast_assign( @@ -218,24 +217,22 @@ TRACE_EVENT(mm_shrink_slab_start, __entry->nid = sc->nid; __entry->nr_objects_to_shrink = nr_objects_to_shrink; __entry->gfp_flags = sc->gfp_mask; - __entry->pgs_scanned = pgs_scanned; - __entry->lru_pgs = lru_pgs; __entry->cache_items = cache_items; __entry->delta = delta; __entry->total_scan = total_scan; + __entry->priority = priority; ), - TP_printk("%pF %p: nid: %d objects to shrink %ld gfp_flags %s pgs_scanned %ld lru_pgs %ld cache items %ld delta %lld total_scan %ld", + TP_printk("%pF %p: nid: %d objects to shrink %ld gfp_flags %s cache items %ld delta %lld total_scan %ld priority %d", __entry->shrink, __entry->shr, __entry->nid, __entry->nr_objects_to_shrink, show_gfp_flags(__entry->gfp_flags), - __entry->pgs_scanned, - __entry->lru_pgs, __entry->cache_items, __entry->delta, - __entry->total_scan) + __entry->total_scan, + __entry->priority) ); TRACE_EVENT(mm_shrink_slab_end, diff --git a/mm/vmscan.c b/mm/vmscan.c index 47d5ced51f2d..e73274a60b22 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -310,9 +310,7 @@ EXPORT_SYMBOL(unregister_shrinker); #define SHRINK_BATCH 128 static unsigned long do_shrink_slab(struct shrink_control *shrinkctl, - struct shrinker *shrinker, - unsigned long nr_scanned, - unsigned long nr_eligible) + struct shrinker *shrinker, int priority) { unsigned long freed = 0; unsigned long long delta; @@ -337,9 +335,9 @@ static unsigned long do_shrink_slab(struct shrink_control *shrinkctl, nr = atomic_long_xchg(&shrinker->nr_deferred[nid], 0); total_scan = nr; - delta = (4 * nr_scanned) / shrinker->seeks; - delta *= freeable; - do_div(delta, nr_eligible + 1); + delta = freeable >> priority; + delta *= 4; + do_div(delta, shrinker->seeks); total_scan += delta; if (total_scan < 0) { pr_err("shrink_slab: %pF negative objects to delete nr=%ld\n", @@ -373,8 +371,7 @@ static unsigned long do_shrink_slab(struct shrink_control *shrinkctl, total_scan = freeable * 2; trace_mm_shrink_slab_start(shrinker, shrinkctl, nr, - nr_scanned, nr_eligible, - freeable, delta, total_scan); + freeable, delta, total_scan, priority); /* * Normally, we should not scan less than batch_size objects in one @@ -434,8 +431,7 @@ static unsigned long do_shrink_slab(struct shrink_control *shrinkctl, * @gfp_mask: allocation context * @nid: node whose slab caches to target * @memcg: memory cgroup whose slab caches to target - * @nr_scanned: pressure numerator - * @nr_eligible: pressure denominator + * @priority: the reclaim priority * * Call the shrink functions to age shrinkable caches. * @@ -447,20 +443,14 @@ static unsigned long do_shrink_slab(struct shrink_control *shrinkctl, * objects from the memory cgroup specified. Otherwise, only unaware * shrinkers are called. * - * @nr_scanned and @nr_eligible form a ratio that indicate how much of - * the available objects should be scanned. Page reclaim for example - * passes the number of pages scanned and the number of pages on the - * LRU lists that it considered on @nid, plus a bias in @nr_scanned - * when it encountered mapped pages. The ratio is further biased by - * the ->seeks setting of the shrink function, which indicates the - * cost to recreate an object relative to that of an LRU page. + * @priority is sc->priority, we take the number of objects and >> by priority + * in order to get the scan target. * * Returns the number of reclaimed slab objects. */ static unsigned long shrink_slab(gfp_t gfp_mask, int nid, struct mem_cgroup *memcg, - unsigned long nr_scanned, - unsigned long nr_eligible) + int priority) { struct shrinker *shrinker; unsigned long freed = 0; @@ -468,9 +458,6 @@ static unsigned long shrink_slab(gfp_t gfp_mask, int nid, if (memcg && (!memcg_kmem_enabled() || !mem_cgroup_online(memcg))) return 0; - if (nr_scanned == 0) - nr_scanned = SWAP_CLUSTER_MAX; - if (!down_read_trylock(&shrinker_rwsem)) { /* * If we would return 0, our callers would understand that we @@ -501,7 +488,7 @@ static unsigned long shrink_slab(gfp_t gfp_mask, int nid, if (!(shrinker->flags & SHRINKER_NUMA_AWARE)) sc.nid = 0; - freed += do_shrink_slab(&sc, shrinker, nr_scanned, nr_eligible); + freed += do_shrink_slab(&sc, shrinker, priority); } up_read(&shrinker_rwsem); @@ -519,8 +506,7 @@ void drop_slab_node(int nid) freed = 0; do { - freed += shrink_slab(GFP_KERNEL, nid, memcg, - 1000, 1000); + freed += shrink_slab(GFP_KERNEL, nid, memcg, 0); } while ((memcg = mem_cgroup_iter(NULL, memcg, NULL)) != NULL); } while (freed > 10); } @@ -2615,14 +2601,12 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc) reclaimed = sc->nr_reclaimed; scanned = sc->nr_scanned; - shrink_node_memcg(pgdat, memcg, sc, &lru_pages); node_lru_pages += lru_pages; if (memcg) shrink_slab(sc->gfp_mask, pgdat->node_id, - memcg, sc->nr_scanned - scanned, - lru_pages); + memcg, sc->priority); /* Record the group's reclaim efficiency */ vmpressure(sc->gfp_mask, memcg, false, @@ -2646,14 +2630,9 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc) } } while ((memcg = mem_cgroup_iter(root, memcg, &reclaim))); - /* - * Shrink the slab caches in the same proportion that - * the eligible LRU pages were scanned. - */ if (global_reclaim(sc)) shrink_slab(sc->gfp_mask, pgdat->node_id, NULL, - sc->nr_scanned - nr_scanned, - node_lru_pages); + sc->priority); if (reclaim_state) { sc->nr_reclaimed += reclaim_state->reclaimed_slab;