From 86298d8b8ceacc17d0192cd6412d2773ff51b27f Mon Sep 17 00:00:00 2001 From: Qi Zheng Date: Mon, 11 Sep 2023 17:44:24 +0800 Subject: [PATCH] md/raid5: dynamically allocate the md-raid5 shrinker In preparation for implementing lockless slab shrink, use new APIs to dynamically allocate the md-raid5 shrinker, so that it can be freed asynchronously via RCU. Then it doesn't need to wait for RCU read-side critical section when releasing the struct r5conf. Link: https://lkml.kernel.org/r/20230911094444.68966-26-zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng Reviewed-by: Muchun Song Reviewed-by: Song Liu Cc: Abhinav Kumar Cc: Alasdair Kergon Cc: Alexander Viro Cc: Alyssa Rosenzweig Cc: Andreas Dilger Cc: Andreas Gruenbacher Cc: Anna Schumaker Cc: Arnd Bergmann Cc: Bob Peterson Cc: Borislav Petkov Cc: Carlos Llamas Cc: Chandan Babu R Cc: Chao Yu Cc: Chris Mason Cc: Christian Brauner Cc: Christian Koenig Cc: Chuck Lever Cc: Coly Li Cc: Dai Ngo Cc: Daniel Vetter Cc: Daniel Vetter Cc: "Darrick J. Wong" Cc: Dave Chinner Cc: Dave Hansen Cc: David Airlie Cc: David Hildenbrand Cc: David Sterba Cc: Dmitry Baryshkov Cc: Gao Xiang Cc: Greg Kroah-Hartman Cc: Huang Rui Cc: Ingo Molnar Cc: Jaegeuk Kim Cc: Jani Nikula Cc: Jan Kara Cc: Jason Wang Cc: Jeff Layton Cc: Jeffle Xu Cc: Joel Fernandes (Google) Cc: Joonas Lahtinen Cc: Josef Bacik Cc: Juergen Gross Cc: Kent Overstreet Cc: Kirill Tkhai Cc: Marijn Suijten Cc: "Michael S. Tsirkin" Cc: Mike Snitzer Cc: Minchan Kim Cc: Muchun Song Cc: Nadav Amit Cc: Neil Brown Cc: Oleksandr Tyshchenko Cc: Olga Kornievskaia Cc: Paul E. McKenney Cc: Richard Weinberger Cc: Rob Clark Cc: Rob Herring Cc: Rodrigo Vivi Cc: Roman Gushchin Cc: Sean Paul Cc: Sergey Senozhatsky Cc: Stefano Stabellini Cc: Steven Price Cc: "Theodore Ts'o" Cc: Thomas Gleixner Cc: Tomeu Vizoso Cc: Tom Talpey Cc: Trond Myklebust Cc: Tvrtko Ursulin Cc: Vlastimil Babka Cc: Xuan Zhuo Cc: Yue Hu Signed-off-by: Andrew Morton --- drivers/md/raid5.c | 26 +++++++++++++++----------- drivers/md/raid5.h | 2 +- 2 files changed, 16 insertions(+), 12 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 4cb9c608ee19..c8d2c6e50aa1 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -7401,7 +7401,7 @@ static void free_conf(struct r5conf *conf) log_exit(conf); - unregister_shrinker(&conf->shrinker); + shrinker_free(conf->shrinker); free_thread_groups(conf); shrink_stripes(conf); raid5_free_percpu(conf); @@ -7449,7 +7449,7 @@ static int raid5_alloc_percpu(struct r5conf *conf) static unsigned long raid5_cache_scan(struct shrinker *shrink, struct shrink_control *sc) { - struct r5conf *conf = container_of(shrink, struct r5conf, shrinker); + struct r5conf *conf = shrink->private_data; unsigned long ret = SHRINK_STOP; if (mutex_trylock(&conf->cache_size_mutex)) { @@ -7470,7 +7470,7 @@ static unsigned long raid5_cache_scan(struct shrinker *shrink, static unsigned long raid5_cache_count(struct shrinker *shrink, struct shrink_control *sc) { - struct r5conf *conf = container_of(shrink, struct r5conf, shrinker); + struct r5conf *conf = shrink->private_data; if (conf->max_nr_stripes < conf->min_nr_stripes) /* unlikely, but not impossible */ @@ -7705,18 +7705,22 @@ static struct r5conf *setup_conf(struct mddev *mddev) * it reduces the queue depth and so can hurt throughput. * So set it rather large, scaled by number of devices. */ - conf->shrinker.seeks = DEFAULT_SEEKS * conf->raid_disks * 4; - conf->shrinker.scan_objects = raid5_cache_scan; - conf->shrinker.count_objects = raid5_cache_count; - conf->shrinker.batch = 128; - conf->shrinker.flags = 0; - ret = register_shrinker(&conf->shrinker, "md-raid5:%s", mdname(mddev)); - if (ret) { - pr_warn("md/raid:%s: couldn't register shrinker.\n", + conf->shrinker = shrinker_alloc(0, "md-raid5:%s", mdname(mddev)); + if (!conf->shrinker) { + ret = -ENOMEM; + pr_warn("md/raid:%s: couldn't allocate shrinker.\n", mdname(mddev)); goto abort; } + conf->shrinker->seeks = DEFAULT_SEEKS * conf->raid_disks * 4; + conf->shrinker->scan_objects = raid5_cache_scan; + conf->shrinker->count_objects = raid5_cache_count; + conf->shrinker->batch = 128; + conf->shrinker->private_data = conf; + + shrinker_register(conf->shrinker); + sprintf(pers_name, "raid%d", mddev->new_level); rcu_assign_pointer(conf->thread, md_register_thread(raid5d, mddev, pers_name)); diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h index 97a795979a35..22bea20eccbd 100644 --- a/drivers/md/raid5.h +++ b/drivers/md/raid5.h @@ -670,7 +670,7 @@ struct r5conf { wait_queue_head_t wait_for_stripe; wait_queue_head_t wait_for_overlap; unsigned long cache_state; - struct shrinker shrinker; + struct shrinker *shrinker; int pool_size; /* number of disks in stripeheads in pool */ spinlock_t device_lock; struct disk_info *disks;