[PATCH v11 24/25] shrinker: Kill old ->shrink API.
From: Glauber Costa <hidden>
Date: 2013-06-06 20:34:57
Also in:
linux-fsdevel, linux-mm
Subsystem:
memory management, memory management - mglru (multi-gen lru), memory management - reclaim, shrinker, the rest, tracing · Maintainers:
Andrew Morton, Johannes Weiner, Dave Chinner, Linus Torvalds, Steven Rostedt, Masami Hiramatsu
From: Dave Chinner <redacted> There are no more users of this API, so kill it dead, dead, dead and quietly bury the corpse in a shallow, unmarked grave in a dark forest deep in the hills... [ glommer: added flowers to the grave ] Signed-off-by: Dave Chinner <redacted> Signed-off-by: Glauber Costa <redacted> Reviewed-by: Greg Thelen <redacted> Acked-by: Mel Gorman <redacted> --- include/linux/shrinker.h | 15 +++++---------- include/trace/events/vmscan.h | 4 ++-- mm/vmscan.c | 40 ++++++++-------------------------------- 3 files changed, 15 insertions(+), 44 deletions(-)
diff --git a/include/linux/shrinker.h b/include/linux/shrinker.h
index 8f80f24..68c0970 100644
--- a/include/linux/shrinker.h
+++ b/include/linux/shrinker.h@@ -7,14 +7,15 @@ * * The 'gfpmask' refers to the allocation we are currently trying to * fulfil. - * - * Note that 'shrink' will be passed nr_to_scan == 0 when the VM is - * querying the cache size, so a fastpath for that case is appropriate. */ struct shrink_control { gfp_t gfp_mask; - /* How many slab objects shrinker() should scan and try to reclaim */ + /* + * How many objects scan_objects should scan and try to reclaim. + * This is reset before every call, so it is safe for callees + * to modify. + */ unsigned long nr_to_scan; /* shrink from these nodes */
@@ -27,11 +28,6 @@ struct shrink_control { /* * A callback you can register to apply pressure to ageable caches. * - * @shrink() should look through the least-recently-used 'nr_to_scan' entries - * and attempt to free them up. It should return the number of objects which - * remain in the cache. If it returns -1, it means it cannot do any scanning at - * this time (eg. there is a risk of deadlock). - * * @count_objects should return the number of freeable items in the cache. If * there are no objects to free or the number of freeable items cannot be * determined, it should return 0. No deadlock checks should be done during the
@@ -50,7 +46,6 @@ struct shrink_control { * @flags determine the shrinker abilities, like numa awareness */ struct shrinker { - int (*shrink)(struct shrinker *, struct shrink_control *sc); unsigned long (*count_objects)(struct shrinker *, struct shrink_control *sc); unsigned long (*scan_objects)(struct shrinker *,
diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index 63cfccc..132a985 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h@@ -202,7 +202,7 @@ TRACE_EVENT(mm_shrink_slab_start, TP_fast_assign( __entry->shr = shr; - __entry->shrink = shr->shrink; + __entry->shrink = shr->scan_objects; __entry->nr_objects_to_shrink = nr_objects_to_shrink; __entry->gfp_flags = sc->gfp_mask; __entry->pgs_scanned = pgs_scanned;
@@ -241,7 +241,7 @@ TRACE_EVENT(mm_shrink_slab_end, TP_fast_assign( __entry->shr = shr; - __entry->shrink = shr->shrink; + __entry->shrink = shr->scan_objects; __entry->unused_scan = unused_scan_cnt; __entry->new_scan = new_scan_cnt; __entry->retval = shrinker_retval;
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 22ac8de..fe73724 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c@@ -194,14 +194,6 @@ void unregister_shrinker(struct shrinker *shrinker) } EXPORT_SYMBOL(unregister_shrinker); -static inline int do_shrinker_shrink(struct shrinker *shrinker, - struct shrink_control *sc, - unsigned long nr_to_scan) -{ - sc->nr_to_scan = nr_to_scan; - return (*shrinker->shrink)(shrinker, sc); -} - #define SHRINK_BATCH 128 static unsigned long
@@ -218,10 +210,7 @@ shrink_slab_node(struct shrink_control *shrinkctl, struct shrinker *shrinker, long batch_size = shrinker->batch ? shrinker->batch : SHRINK_BATCH; - if (shrinker->count_objects) - max_pass = shrinker->count_objects(shrinker, shrinkctl); - else - max_pass = do_shrinker_shrink(shrinker, shrinkctl, 0); + max_pass = shrinker->count_objects(shrinker, shrinkctl); if (max_pass == 0) return 0;
@@ -240,7 +229,7 @@ shrink_slab_node(struct shrink_control *shrinkctl, struct shrinker *shrinker, if (total_scan < 0) { printk(KERN_ERR "shrink_slab: %pF negative objects to delete nr=%ld\n", - shrinker->shrink, total_scan); + shrinker->scan_objects, total_scan); total_scan = max_pass; }
@@ -273,26 +262,13 @@ shrink_slab_node(struct shrink_control *shrinkctl, struct shrinker *shrinker, while (total_scan >= batch_size) { - if (shrinker->scan_objects) { - unsigned long ret; - shrinkctl->nr_to_scan = batch_size; - ret = shrinker->scan_objects(shrinker, shrinkctl); - - if (ret == SHRINK_STOP) - break; - freed += ret; - } else { - int nr_before; - long ret; + unsigned long ret; + shrinkctl->nr_to_scan = batch_size; + ret = shrinker->scan_objects(shrinker, shrinkctl); - nr_before = do_shrinker_shrink(shrinker, shrinkctl, 0); - ret = do_shrinker_shrink(shrinker, shrinkctl, - batch_size); - if (ret == -1) - break; - if (ret < nr_before) - freed += nr_before - ret; - } + if (ret == SHRINK_STOP) + break; + freed += ret; count_vm_events(SLABS_SCANNED, batch_size); total_scan -= batch_size;
--
1.8.1.4