From: Kirill Tkhai Date: Mon, 27 Aug 2018 15:29:46 +0000 (+0300) Subject: fuse: introduce fc->bg_lock X-Git-Tag: v5.4-rc1~2297^2~22 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ae2dffa39485c6fd4f22321814c7287c274b473a;p=platform%2Fkernel%2Flinux-rpi.git fuse: introduce fc->bg_lock To reduce contention of fc->lock, this patch introduces bg_lock for protection of fields related to background queue. These are: max_background, congestion_threshold, num_background, active_background, bg_queue and blocked. This allows next patch to make async reads not requiring fc->lock, so async reads and writes will have better performance executed in parallel. Signed-off-by: Kirill Tkhai Signed-off-by: Miklos Szeredi --- diff --git a/fs/fuse/control.c b/fs/fuse/control.c index eaa0e2b2..989df5a 100644 --- a/fs/fuse/control.c +++ b/fs/fuse/control.c @@ -125,12 +125,12 @@ static ssize_t fuse_conn_max_background_write(struct file *file, if (ret > 0) { struct fuse_conn *fc = fuse_ctl_file_conn_get(file); if (fc) { - spin_lock(&fc->lock); + spin_lock(&fc->bg_lock); fc->max_background = val; fc->blocked = fc->num_background >= fc->max_background; if (!fc->blocked) wake_up(&fc->blocked_waitq); - spin_unlock(&fc->lock); + spin_unlock(&fc->bg_lock); fuse_conn_put(fc); } } @@ -171,7 +171,7 @@ static ssize_t fuse_conn_congestion_threshold_write(struct file *file, if (!fc) goto out; - spin_lock(&fc->lock); + spin_lock(&fc->bg_lock); fc->congestion_threshold = val; if (fc->sb) { if (fc->num_background < fc->congestion_threshold) { @@ -182,7 +182,7 @@ static ssize_t fuse_conn_congestion_threshold_write(struct file *file, set_bdi_congested(fc->sb->s_bdi, BLK_RW_ASYNC); } } - spin_unlock(&fc->lock); + spin_unlock(&fc->bg_lock); fuse_conn_put(fc); out: return ret; diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index 6a7d3b4..d4b9ffc 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -287,10 +287,10 @@ void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req) * We get here in the unlikely case that a background * request was allocated but not sent */ - spin_lock(&fc->lock); + spin_lock(&fc->bg_lock); if (!fc->blocked) wake_up(&fc->blocked_waitq); - spin_unlock(&fc->lock); + spin_unlock(&fc->bg_lock); } if (test_bit(FR_WAITING, &req->flags)) { @@ -390,7 +390,7 @@ static void request_end(struct fuse_conn *fc, struct fuse_req *req) WARN_ON(test_bit(FR_PENDING, &req->flags)); WARN_ON(test_bit(FR_SENT, &req->flags)); if (test_bit(FR_BACKGROUND, &req->flags)) { - spin_lock(&fc->lock); + spin_lock(&fc->bg_lock); clear_bit(FR_BACKGROUND, &req->flags); if (fc->num_background == fc->max_background) { fc->blocked = 0; @@ -413,7 +413,7 @@ static void request_end(struct fuse_conn *fc, struct fuse_req *req) fc->num_background--; fc->active_background--; flush_bg_queue(fc); - spin_unlock(&fc->lock); + spin_unlock(&fc->bg_lock); } wake_up(&req->waitq); if (req->end) @@ -586,8 +586,8 @@ ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args) * * fc->connected must have been checked previously */ -void fuse_request_send_background_locked(struct fuse_conn *fc, - struct fuse_req *req) +void fuse_request_send_background_nocheck(struct fuse_conn *fc, + struct fuse_req *req) { BUG_ON(!test_bit(FR_BACKGROUND, &req->flags)); if (!test_bit(FR_WAITING, &req->flags)) { @@ -595,6 +595,7 @@ void fuse_request_send_background_locked(struct fuse_conn *fc, atomic_inc(&fc->num_waiting); } __set_bit(FR_ISREPLY, &req->flags); + spin_lock(&fc->bg_lock); fc->num_background++; if (fc->num_background == fc->max_background) fc->blocked = 1; @@ -604,6 +605,7 @@ void fuse_request_send_background_locked(struct fuse_conn *fc, } list_add_tail(&req->list, &fc->bg_queue); flush_bg_queue(fc); + spin_unlock(&fc->bg_lock); } void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req) @@ -611,7 +613,7 @@ void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req) BUG_ON(!req->end); spin_lock(&fc->lock); if (fc->connected) { - fuse_request_send_background_locked(fc, req); + fuse_request_send_background_nocheck(fc, req); spin_unlock(&fc->lock); } else { spin_unlock(&fc->lock); @@ -2118,7 +2120,6 @@ void fuse_abort_conn(struct fuse_conn *fc, bool is_abort) LIST_HEAD(to_end); fc->connected = 0; - fc->blocked = 0; fc->aborted = is_abort; fuse_set_initialized(fc); list_for_each_entry(fud, &fc->devices, entry) { @@ -2140,8 +2141,11 @@ void fuse_abort_conn(struct fuse_conn *fc, bool is_abort) list_splice_tail_init(&fpq->processing, &to_end); spin_unlock(&fpq->lock); } + spin_lock(&fc->bg_lock); + fc->blocked = 0; fc->max_background = UINT_MAX; flush_bg_queue(fc); + spin_unlock(&fc->bg_lock); spin_lock(&fiq->waitq.lock); fiq->connected = 0; diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 63136a2..65351d4 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -1502,7 +1502,7 @@ __acquires(fc->lock) req->in.args[1].size = inarg->size; fi->writectr++; - fuse_request_send_background_locked(fc, req); + fuse_request_send_background_nocheck(fc, req); return; out_free: diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 3e45d40..d6d5564 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -500,6 +500,10 @@ struct fuse_conn { /** The list of background requests set aside for later queuing */ struct list_head bg_queue; + /** Protects: max_background, congestion_threshold, num_background, + * active_background, bg_queue, blocked */ + spinlock_t bg_lock; + /** Flag indicating that INIT reply has been received. Allocating * any fuse request will be suspended until the flag is set */ int initialized; @@ -860,8 +864,8 @@ ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args); */ void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req); -void fuse_request_send_background_locked(struct fuse_conn *fc, - struct fuse_req *req); +void fuse_request_send_background_nocheck(struct fuse_conn *fc, + struct fuse_req *req); /* Abort all requests */ void fuse_abort_conn(struct fuse_conn *fc, bool is_abort); diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index db9e60b..ed3f496 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -605,6 +605,7 @@ void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns) { memset(fc, 0, sizeof(*fc)); spin_lock_init(&fc->lock); + spin_lock_init(&fc->bg_lock); init_rwsem(&fc->killsb); refcount_set(&fc->count, 1); atomic_set(&fc->dev_count, 1); @@ -852,6 +853,7 @@ static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg) sanitize_global_limit(&max_user_bgreq); sanitize_global_limit(&max_user_congthresh); + spin_lock(&fc->bg_lock); if (arg->max_background) { fc->max_background = arg->max_background; @@ -865,6 +867,7 @@ static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg) fc->congestion_threshold > max_user_congthresh) fc->congestion_threshold = max_user_congthresh; } + spin_unlock(&fc->bg_lock); } static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)