From fe55d563d4174f13839a9b7ef7309da5031b5d93 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 22 Mar 2022 14:39:07 -0700 Subject: remove inode_congested() inode_congested() reports if the backing-device for the inode is congested. No bdi reports congestion any more, so this always returns 'false'. So remove inode_congested() and related functions, and remove the call sites, assuming that inode_congested() always returns 'false'. Link: https://lkml.kernel.org/r/164549983741.9187.2174285592262191311.stgit@noble.brown Signed-off-by: NeilBrown Cc: Anna Schumaker Cc: Chao Yu Cc: Darrick J. Wong Cc: Ilya Dryomov Cc: Jaegeuk Kim Cc: Jan Kara Cc: Jeff Layton Cc: Jens Axboe Cc: Lars Ellenberg Cc: Miklos Szeredi Cc: Paolo Valente Cc: Philipp Reisner Cc: Ryusuke Konishi Cc: Trond Myklebust Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/backing-dev.h | 22 ---------------------- 1 file changed, 22 deletions(-) (limited to 'include/linux/backing-dev.h') diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 483979c1b9f4..860b675c2929 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -162,7 +162,6 @@ struct bdi_writeback *wb_get_create(struct backing_dev_info *bdi, gfp_t gfp); void wb_memcg_offline(struct mem_cgroup *memcg); void wb_blkcg_offline(struct blkcg *blkcg); -int inode_congested(struct inode *inode, int cong_bits); /** * inode_cgwb_enabled - test whether cgroup writeback is enabled on an inode @@ -390,29 +389,8 @@ static inline void wb_blkcg_offline(struct blkcg *blkcg) { } -static inline int inode_congested(struct inode *inode, int cong_bits) -{ - return wb_congested(&inode_to_bdi(inode)->wb, cong_bits); -} - #endif /* CONFIG_CGROUP_WRITEBACK */ -static inline int inode_read_congested(struct inode *inode) -{ - return inode_congested(inode, 1 << WB_sync_congested); -} - -static inline int inode_write_congested(struct inode *inode) -{ - return inode_congested(inode, 1 << WB_async_congested); -} - -static inline int inode_rw_congested(struct inode *inode) -{ - return inode_congested(inode, (1 << WB_sync_congested) | - (1 << WB_async_congested)); -} - static inline int bdi_congested(struct backing_dev_info *bdi, int cong_bits) { return wb_congested(&bdi->wb, cong_bits); -- cgit v1.2.3 From b9b1335e640308acc1b8f26c739b804c80a6c147 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 22 Mar 2022 14:39:10 -0700 Subject: remove bdi_congested() and wb_congested() and related functions These functions are no longer useful as no BDIs report congestions any more. Removing the test on bdi_write_contested() in current_may_throttle() could cause a small change in behaviour, but only when PF_LOCAL_THROTTLE is set. So replace the calls by 'false' and simplify the code - and remove the functions. [akpm@linux-foundation.org: fix build] Link: https://lkml.kernel.org/r/164549983742.9187.2570198746005819592.stgit@noble.brown Signed-off-by: NeilBrown Acked-by: Ryusuke Konishi [nilfs] Cc: Anna Schumaker Cc: Chao Yu Cc: Darrick J. Wong Cc: Ilya Dryomov Cc: Jaegeuk Kim Cc: Jan Kara Cc: Jeff Layton Cc: Jens Axboe Cc: Lars Ellenberg Cc: Miklos Szeredi Cc: Paolo Valente Cc: Philipp Reisner Cc: Trond Myklebust Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/block/drbd/drbd_int.h | 3 --- drivers/block/drbd/drbd_req.c | 3 +-- fs/ext2/ialloc.c | 5 ----- fs/nilfs2/segbuf.c | 16 ---------------- fs/xfs/xfs_buf.c | 3 --- include/linux/backing-dev.h | 26 -------------------------- mm/vmscan.c | 4 +--- 7 files changed, 2 insertions(+), 58 deletions(-) (limited to 'include/linux/backing-dev.h') diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index f27d5b0f9a0b..f804b1bfb3e6 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -638,9 +638,6 @@ enum { STATE_SENT, /* Do not change state/UUIDs while this is set */ CALLBACK_PENDING, /* Whether we have a call_usermodehelper(, UMH_WAIT_PROC) * pending, from drbd worker context. - * If set, bdi_write_congested() returns true, - * so shrink_page_list() would not recurse into, - * and potentially deadlock on, this drbd worker. */ DISCONNECT_SENT, diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index 3235532ae077..2e5fb7e442e3 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -909,8 +909,7 @@ static bool remote_due_to_read_balancing(struct drbd_device *device, sector_t se switch (rbm) { case RB_CONGESTED_REMOTE: - return bdi_read_congested( - device->ldev->backing_bdev->bd_disk->bdi); + return 0; case RB_LEAST_PENDING: return atomic_read(&device->local_cnt) > atomic_read(&device->ap_pending_cnt) + atomic_read(&device->rs_pending_cnt); diff --git a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c index df14e750e9fe..998dd2ac8008 100644 --- a/fs/ext2/ialloc.c +++ b/fs/ext2/ialloc.c @@ -170,11 +170,6 @@ static void ext2_preread_inode(struct inode *inode) unsigned long offset; unsigned long block; struct ext2_group_desc * gdp; - struct backing_dev_info *bdi; - - bdi = inode_to_bdi(inode); - if (bdi_rw_congested(bdi)) - return; block_group = (inode->i_ino - 1) / EXT2_INODES_PER_GROUP(inode->i_sb); gdp = ext2_get_group_desc(inode->i_sb, block_group, NULL); diff --git a/fs/nilfs2/segbuf.c b/fs/nilfs2/segbuf.c index 43287b0d3e9b..f4b57bc0c586 100644 --- a/fs/nilfs2/segbuf.c +++ b/fs/nilfs2/segbuf.c @@ -341,18 +341,6 @@ static int nilfs_segbuf_submit_bio(struct nilfs_segment_buffer *segbuf, int mode_flags) { struct bio *bio = wi->bio; - int err; - - if (segbuf->sb_nbio > 0 && - bdi_write_congested(segbuf->sb_super->s_bdi)) { - wait_for_completion(&segbuf->sb_bio_event); - segbuf->sb_nbio--; - if (unlikely(atomic_read(&segbuf->sb_err))) { - bio_put(bio); - err = -EIO; - goto failed; - } - } bio->bi_end_io = nilfs_end_bio_write; bio->bi_private = segbuf; @@ -365,10 +353,6 @@ static int nilfs_segbuf_submit_bio(struct nilfs_segment_buffer *segbuf, wi->nr_vecs = min(wi->max_pages, wi->rest_blocks); wi->start = wi->end; return 0; - - failed: - wi->bio = NULL; - return err; } /** diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index b45e0d50a405..b7ebcfe6b8d3 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -843,9 +843,6 @@ xfs_buf_readahead_map( { struct xfs_buf *bp; - if (bdi_read_congested(target->bt_bdev->bd_disk->bdi)) - return; - xfs_buf_read_map(target, map, nmaps, XBF_TRYLOCK | XBF_ASYNC | XBF_READ_AHEAD, &bp, ops, __this_address); diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 860b675c2929..2d764566280c 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -135,11 +135,6 @@ static inline bool writeback_in_progress(struct bdi_writeback *wb) struct backing_dev_info *inode_to_bdi(struct inode *inode); -static inline int wb_congested(struct bdi_writeback *wb, int cong_bits) -{ - return wb->congested & cong_bits; -} - long congestion_wait(int sync, long timeout); static inline bool mapping_can_writeback(struct address_space *mapping) @@ -391,27 +386,6 @@ static inline void wb_blkcg_offline(struct blkcg *blkcg) #endif /* CONFIG_CGROUP_WRITEBACK */ -static inline int bdi_congested(struct backing_dev_info *bdi, int cong_bits) -{ - return wb_congested(&bdi->wb, cong_bits); -} - -static inline int bdi_read_congested(struct backing_dev_info *bdi) -{ - return bdi_congested(bdi, 1 << WB_sync_congested); -} - -static inline int bdi_write_congested(struct backing_dev_info *bdi) -{ - return bdi_congested(bdi, 1 << WB_async_congested); -} - -static inline int bdi_rw_congested(struct backing_dev_info *bdi) -{ - return bdi_congested(bdi, (1 << WB_sync_congested) | - (1 << WB_async_congested)); -} - const char *bdi_dev_name(struct backing_dev_info *bdi); #endif /* _LINUX_BACKING_DEV_H */ diff --git a/mm/vmscan.c b/mm/vmscan.c index e38de6456cdc..5e1469887afa 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2364,9 +2364,7 @@ static unsigned int move_pages_to_lru(struct lruvec *lruvec, */ static int current_may_throttle(void) { - return !(current->flags & PF_LOCAL_THROTTLE) || - current->backing_dev_info == NULL || - bdi_write_congested(current->backing_dev_info); + return !(current->flags & PF_LOCAL_THROTTLE); } /* -- cgit v1.2.3 From a88f2096d5a2d91179db5dd9aa8f60dc3df9bb3e Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Tue, 22 Mar 2022 14:39:19 -0700 Subject: remove congestion tracking framework This framework is no longer used - so discard it. Link: https://lkml.kernel.org/r/164549983747.9187.6171768583526866601.stgit@noble.brown Signed-off-by: NeilBrown Cc: Anna Schumaker Cc: Chao Yu Cc: Darrick J. Wong Cc: Ilya Dryomov Cc: Jaegeuk Kim Cc: Jan Kara Cc: Jeff Layton Cc: Jens Axboe Cc: Lars Ellenberg Cc: Miklos Szeredi Cc: Paolo Valente Cc: Philipp Reisner Cc: Ryusuke Konishi Cc: Trond Myklebust Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/backing-dev-defs.h | 8 ------ include/linux/backing-dev.h | 2 -- include/trace/events/writeback.h | 28 -------------------- mm/backing-dev.c | 57 ---------------------------------------- 4 files changed, 95 deletions(-) (limited to 'include/linux/backing-dev.h') diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h index 993c5628a726..e863c88df95f 100644 --- a/include/linux/backing-dev-defs.h +++ b/include/linux/backing-dev-defs.h @@ -207,14 +207,6 @@ struct backing_dev_info { #endif }; -enum { - BLK_RW_ASYNC = 0, - BLK_RW_SYNC = 1, -}; - -void clear_bdi_congested(struct backing_dev_info *bdi, int sync); -void set_bdi_congested(struct backing_dev_info *bdi, int sync); - struct wb_lock_cookie { bool locked; unsigned long flags; diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 2d764566280c..87ce24d238f3 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -135,8 +135,6 @@ static inline bool writeback_in_progress(struct bdi_writeback *wb) struct backing_dev_info *inode_to_bdi(struct inode *inode); -long congestion_wait(int sync, long timeout); - static inline bool mapping_can_writeback(struct address_space *mapping) { return inode_to_bdi(mapping->host)->capabilities & BDI_CAP_WRITEBACK; diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h index a345b1e12daf..86b2a82da546 100644 --- a/include/trace/events/writeback.h +++ b/include/trace/events/writeback.h @@ -735,34 +735,6 @@ TRACE_EVENT(writeback_sb_inodes_requeue, ) ); -DECLARE_EVENT_CLASS(writeback_congest_waited_template, - - TP_PROTO(unsigned int usec_timeout, unsigned int usec_delayed), - - TP_ARGS(usec_timeout, usec_delayed), - - TP_STRUCT__entry( - __field( unsigned int, usec_timeout ) - __field( unsigned int, usec_delayed ) - ), - - TP_fast_assign( - __entry->usec_timeout = usec_timeout; - __entry->usec_delayed = usec_delayed; - ), - - TP_printk("usec_timeout=%u usec_delayed=%u", - __entry->usec_timeout, - __entry->usec_delayed) -); - -DEFINE_EVENT(writeback_congest_waited_template, writeback_congestion_wait, - - TP_PROTO(unsigned int usec_timeout, unsigned int usec_delayed), - - TP_ARGS(usec_timeout, usec_delayed) -); - DECLARE_EVENT_CLASS(writeback_single_inode_template, TP_PROTO(struct inode *inode, diff --git a/mm/backing-dev.c b/mm/backing-dev.c index eae96dfe0261..7176af65b103 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -1005,60 +1005,3 @@ const char *bdi_dev_name(struct backing_dev_info *bdi) return bdi->dev_name; } EXPORT_SYMBOL_GPL(bdi_dev_name); - -static wait_queue_head_t congestion_wqh[2] = { - __WAIT_QUEUE_HEAD_INITIALIZER(congestion_wqh[0]), - __WAIT_QUEUE_HEAD_INITIALIZER(congestion_wqh[1]) - }; -static atomic_t nr_wb_congested[2]; - -void clear_bdi_congested(struct backing_dev_info *bdi, int sync) -{ - wait_queue_head_t *wqh = &congestion_wqh[sync]; - enum wb_congested_state bit; - - bit = sync ? WB_sync_congested : WB_async_congested; - if (test_and_clear_bit(bit, &bdi->wb.congested)) - atomic_dec(&nr_wb_congested[sync]); - smp_mb__after_atomic(); - if (waitqueue_active(wqh)) - wake_up(wqh); -} -EXPORT_SYMBOL(clear_bdi_congested); - -void set_bdi_congested(struct backing_dev_info *bdi, int sync) -{ - enum wb_congested_state bit; - - bit = sync ? WB_sync_congested : WB_async_congested; - if (!test_and_set_bit(bit, &bdi->wb.congested)) - atomic_inc(&nr_wb_congested[sync]); -} -EXPORT_SYMBOL(set_bdi_congested); - -/** - * congestion_wait - wait for a backing_dev to become uncongested - * @sync: SYNC or ASYNC IO - * @timeout: timeout in jiffies - * - * Waits for up to @timeout jiffies for a backing_dev (any backing_dev) to exit - * write congestion. If no backing_devs are congested then just wait for the - * next write to be completed. - */ -long congestion_wait(int sync, long timeout) -{ - long ret; - unsigned long start = jiffies; - DEFINE_WAIT(wait); - wait_queue_head_t *wqh = &congestion_wqh[sync]; - - prepare_to_wait(wqh, &wait, TASK_UNINTERRUPTIBLE); - ret = io_schedule_timeout(timeout); - finish_wait(wqh, &wait); - - trace_writeback_congestion_wait(jiffies_to_usecs(timeout), - jiffies_to_usecs(jiffies - start)); - - return ret; -} -EXPORT_SYMBOL(congestion_wait); -- cgit v1.2.3 From dec223c92a4688f6c9642d640cfe15a99d289dd4 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 20 Apr 2022 06:27:15 +0200 Subject: blk-cgroup: move struct blkcg to block/blk-cgroup.h There is no real need to expose the blkcg structure to the whole kernel. Move it to the private header an expose a helper to let the writeback code access the cgwb_list member. Signed-off-by: Christoph Hellwig Acked-by: Tejun Heo Link: https://lore.kernel.org/r/20220420042723.1010598-8-hch@lst.de Signed-off-by: Jens Axboe --- block/blk-cgroup.c | 9 ++++++++- block/blk-cgroup.h | 28 ++++++++++++++++++++++++++++ include/linux/backing-dev.h | 6 ++---- include/linux/blk-cgroup.h | 32 +------------------------------- mm/backing-dev.c | 13 ++++++------- 5 files changed, 45 insertions(+), 43 deletions(-) (limited to 'include/linux/backing-dev.h') diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 3af0d4a61955..bb52797c02bd 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -1005,6 +1005,13 @@ static struct cftype blkcg_legacy_files[] = { { } /* terminate */ }; +#ifdef CONFIG_CGROUP_WRITEBACK +struct list_head *blkcg_get_cgwb_list(struct cgroup_subsys_state *css) +{ + return &css_to_blkcg(css)->cgwb_list; +} +#endif + /* * blkcg destruction is a three-stage process. * @@ -1112,7 +1119,7 @@ void blkcg_unpin_online(struct cgroup_subsys_state *blkcg_css) static void blkcg_css_offline(struct cgroup_subsys_state *css) { /* this prevents anyone from attaching or migrating to this blkcg */ - wb_blkcg_offline(css_to_blkcg(css)); + wb_blkcg_offline(css); /* put the base online pin allowing step 2 to be triggered */ blkcg_unpin_online(css); diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h index 49e88fc9cc39..b00fb1169e7c 100644 --- a/block/blk-cgroup.h +++ b/block/blk-cgroup.h @@ -17,10 +17,38 @@ #include #include +struct blkcg_gq; +struct blkg_policy_data; + + /* percpu_counter batch for blkg_[rw]stats, per-cpu drift doesn't matter */ #define BLKG_STAT_CPU_BATCH (INT_MAX / 2) #ifdef CONFIG_BLK_CGROUP +struct blkcg { + struct cgroup_subsys_state css; + spinlock_t lock; + refcount_t online_pin; + + struct radix_tree_root blkg_tree; + struct blkcg_gq __rcu *blkg_hint; + struct hlist_head blkg_list; + + struct blkcg_policy_data *cpd[BLKCG_MAX_POLS]; + + struct list_head all_blkcgs_node; +#ifdef CONFIG_BLK_CGROUP_FC_APPID + char fc_app_id[FC_APPID_LEN]; +#endif +#ifdef CONFIG_CGROUP_WRITEBACK + struct list_head cgwb_list; +#endif +}; + +static inline struct blkcg *css_to_blkcg(struct cgroup_subsys_state *css) +{ + return css ? container_of(css, struct blkcg, css) : NULL; +} /* * A blkcg_gq (blkg) is association between a block cgroup (blkcg) and a diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 87ce24d238f3..2bd073fa6bb5 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -17,8 +17,6 @@ #include #include -struct blkcg; - static inline struct backing_dev_info *bdi_get(struct backing_dev_info *bdi) { kref_get(&bdi->refcnt); @@ -154,7 +152,7 @@ struct bdi_writeback *wb_get_create(struct backing_dev_info *bdi, struct cgroup_subsys_state *memcg_css, gfp_t gfp); void wb_memcg_offline(struct mem_cgroup *memcg); -void wb_blkcg_offline(struct blkcg *blkcg); +void wb_blkcg_offline(struct cgroup_subsys_state *css); /** * inode_cgwb_enabled - test whether cgroup writeback is enabled on an inode @@ -378,7 +376,7 @@ static inline void wb_memcg_offline(struct mem_cgroup *memcg) { } -static inline void wb_blkcg_offline(struct blkcg *blkcg) +static inline void wb_blkcg_offline(struct cgroup_subsys_state *css) { } diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index 0fb7459096e9..d7b188095040 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -37,29 +37,6 @@ enum blkg_iostat_type { BLKG_IOSTAT_NR, }; -struct blkcg_gq; -struct blkg_policy_data; - -struct blkcg { - struct cgroup_subsys_state css; - spinlock_t lock; - refcount_t online_pin; - - struct radix_tree_root blkg_tree; - struct blkcg_gq __rcu *blkg_hint; - struct hlist_head blkg_list; - - struct blkcg_policy_data *cpd[BLKCG_MAX_POLS]; - - struct list_head all_blkcgs_node; -#ifdef CONFIG_BLK_CGROUP_FC_APPID - char fc_app_id[FC_APPID_LEN]; -#endif -#ifdef CONFIG_CGROUP_WRITEBACK - struct list_head cgwb_list; -#endif -}; - struct blkg_iostat { u64 bytes[BLKG_IOSTAT_NR]; u64 ios[BLKG_IOSTAT_NR]; @@ -114,11 +91,6 @@ extern struct cgroup_subsys_state * const blkcg_root_css; void blkcg_schedule_throttle(struct request_queue *q, bool use_memdelay); void blkcg_maybe_throttle_current(void); -static inline struct blkcg *css_to_blkcg(struct cgroup_subsys_state *css) -{ - return css ? container_of(css, struct blkcg, css) : NULL; -} - /** * bio_blkcg - grab the blkcg associated with a bio * @bio: target bio @@ -137,12 +109,10 @@ static inline struct blkcg *bio_blkcg(struct bio *bio) bool blk_cgroup_congested(void); void blkcg_pin_online(struct cgroup_subsys_state *blkcg_css); void blkcg_unpin_online(struct cgroup_subsys_state *blkcg_css); +struct list_head *blkcg_get_cgwb_list(struct cgroup_subsys_state *css); #else /* CONFIG_BLK_CGROUP */ -struct blkcg { -}; - struct blkcg_gq { }; diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 93cddbcd4eb8..98f8f62e52ca 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -445,7 +445,6 @@ static int cgwb_create(struct backing_dev_info *bdi, { struct mem_cgroup *memcg; struct cgroup_subsys_state *blkcg_css; - struct blkcg *blkcg; struct list_head *memcg_cgwb_list, *blkcg_cgwb_list; struct bdi_writeback *wb; unsigned long flags; @@ -453,9 +452,8 @@ static int cgwb_create(struct backing_dev_info *bdi, memcg = mem_cgroup_from_css(memcg_css); blkcg_css = cgroup_get_e_css(memcg_css->cgroup, &io_cgrp_subsys); - blkcg = css_to_blkcg(blkcg_css); memcg_cgwb_list = &memcg->cgwb_list; - blkcg_cgwb_list = &blkcg->cgwb_list; + blkcg_cgwb_list = blkcg_get_cgwb_list(blkcg_css); /* look up again under lock and discard on blkcg mismatch */ spin_lock_irqsave(&cgwb_lock, flags); @@ -723,18 +721,19 @@ void wb_memcg_offline(struct mem_cgroup *memcg) /** * wb_blkcg_offline - kill all wb's associated with a blkcg being offlined - * @blkcg: blkcg being offlined + * @css: blkcg being offlined * * Also prevents creation of any new wb's associated with @blkcg. */ -void wb_blkcg_offline(struct blkcg *blkcg) +void wb_blkcg_offline(struct cgroup_subsys_state *css) { struct bdi_writeback *wb, *next; + struct list_head *list = blkcg_get_cgwb_list(css); spin_lock_irq(&cgwb_lock); - list_for_each_entry_safe(wb, next, &blkcg->cgwb_list, blkcg_node) + list_for_each_entry_safe(wb, next, list, blkcg_node) cgwb_kill(wb); - blkcg->cgwb_list.next = NULL; /* prevent new wb's */ + list->next = NULL; /* prevent new wb's */ spin_unlock_irq(&cgwb_lock); } -- cgit v1.2.3 From 4bca7e80b6455772b4bf3f536dcbc19aac424d6a Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 15 Jun 2022 15:22:29 +0200 Subject: init: Initialize noop_backing_dev_info early noop_backing_dev_info is used by superblocks of various pseudofilesystems such as kdevtmpfs. After commit 10e14073107d ("writeback: Fix inode->i_io_list not be protected by inode->i_lock error") this broke because __mark_inode_dirty() started to access more fields from noop_backing_dev_info and this led to crashes inside locked_inode_to_wb_and_lock_list() called from __mark_inode_dirty(). Fix the problem by initializing noop_backing_dev_info before the filesystems get mounted. Fixes: 10e14073107d ("writeback: Fix inode->i_io_list not be protected by inode->i_lock error") Reported-and-tested-by: Suzuki K Poulose Reported-and-tested-by: Alexandru Elisei Reported-and-tested-by: Guenter Roeck Reviewed-by: Christoph Hellwig Signed-off-by: Jan Kara --- drivers/base/init.c | 2 ++ include/linux/backing-dev.h | 2 ++ mm/backing-dev.c | 11 ++--------- 3 files changed, 6 insertions(+), 9 deletions(-) (limited to 'include/linux/backing-dev.h') diff --git a/drivers/base/init.c b/drivers/base/init.c index d8d0fe687111..397eb9880cec 100644 --- a/drivers/base/init.c +++ b/drivers/base/init.c @@ -8,6 +8,7 @@ #include #include #include +#include #include "base.h" @@ -20,6 +21,7 @@ void __init driver_init(void) { /* These are the core pieces */ + bdi_init(&noop_backing_dev_info); devtmpfs_init(); devices_init(); buses_init(); diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 2bd073fa6bb5..d452071db572 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -119,6 +119,8 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); extern struct backing_dev_info noop_backing_dev_info; +int bdi_init(struct backing_dev_info *bdi); + /** * writeback_in_progress - determine whether there is writeback in progress * @wb: bdi_writeback of interest diff --git a/mm/backing-dev.c b/mm/backing-dev.c index ff60bd7d74e0..95550b8fa7fe 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -231,20 +231,13 @@ static __init int bdi_class_init(void) } postcore_initcall(bdi_class_init); -static int bdi_init(struct backing_dev_info *bdi); - static int __init default_bdi_init(void) { - int err; - bdi_wq = alloc_workqueue("writeback", WQ_MEM_RECLAIM | WQ_UNBOUND | WQ_SYSFS, 0); if (!bdi_wq) return -ENOMEM; - - err = bdi_init(&noop_backing_dev_info); - - return err; + return 0; } subsys_initcall(default_bdi_init); @@ -781,7 +774,7 @@ static void cgwb_remove_from_bdi_list(struct bdi_writeback *wb) #endif /* CONFIG_CGROUP_WRITEBACK */ -static int bdi_init(struct backing_dev_info *bdi) +int bdi_init(struct backing_dev_info *bdi) { int ret; -- cgit v1.2.3