From 87709e28dc7c669af1126aa7352ff6f7b035412d Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 30 May 2016 16:48:35 +0200 Subject: fs/locks: Use percpu_down_read_preempt_disable() Avoid spurious preemption. Signed-off-by: Peter Zijlstra (Intel) Cc: Al Viro Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: dave@stgolabs.net Cc: der.herr@hofr.at Cc: paulmck@linux.vnet.ibm.com Cc: riel@redhat.com Cc: tj@kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- fs/locks.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/fs/locks.c b/fs/locks.c index c33aa77fada2..133fb2543d21 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -930,7 +930,7 @@ static int flock_lock_inode(struct inode *inode, struct file_lock *request) return -ENOMEM; } - percpu_down_read(&file_rwsem); + percpu_down_read_preempt_disable(&file_rwsem); spin_lock(&ctx->flc_lock); if (request->fl_flags & FL_ACCESS) goto find_conflict; @@ -971,7 +971,7 @@ find_conflict: out: spin_unlock(&ctx->flc_lock); - percpu_up_read(&file_rwsem); + percpu_up_read_preempt_enable(&file_rwsem); if (new_fl) locks_free_lock(new_fl); locks_dispose_list(&dispose); @@ -1008,7 +1008,7 @@ static int posix_lock_inode(struct inode *inode, struct file_lock *request, new_fl2 = locks_alloc_lock(); } - percpu_down_read(&file_rwsem); + percpu_down_read_preempt_disable(&file_rwsem); spin_lock(&ctx->flc_lock); /* * New lock request. Walk all POSIX locks and look for conflicts. If @@ -1180,7 +1180,7 @@ static int posix_lock_inode(struct inode *inode, struct file_lock *request, } out: spin_unlock(&ctx->flc_lock); - percpu_up_read(&file_rwsem); + percpu_up_read_preempt_enable(&file_rwsem); /* * Free any unused locks. */ @@ -1455,7 +1455,7 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type) return error; } - percpu_down_read(&file_rwsem); + percpu_down_read_preempt_disable(&file_rwsem); spin_lock(&ctx->flc_lock); time_out_leases(inode, &dispose); @@ -1507,13 +1507,13 @@ restart: locks_insert_block(fl, new_fl); trace_break_lease_block(inode, new_fl); spin_unlock(&ctx->flc_lock); - percpu_up_read(&file_rwsem); + percpu_up_read_preempt_enable(&file_rwsem); locks_dispose_list(&dispose); error = wait_event_interruptible_timeout(new_fl->fl_wait, !new_fl->fl_next, break_time); - percpu_down_read(&file_rwsem); + percpu_down_read_preempt_disable(&file_rwsem); spin_lock(&ctx->flc_lock); trace_break_lease_unblock(inode, new_fl); locks_delete_block(new_fl); @@ -1530,7 +1530,7 @@ restart: } out: spin_unlock(&ctx->flc_lock); - percpu_up_read(&file_rwsem); + percpu_up_read_preempt_enable(&file_rwsem); locks_dispose_list(&dispose); locks_free_lock(new_fl); return error; @@ -1685,7 +1685,7 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr return -EINVAL; } - percpu_down_read(&file_rwsem); + percpu_down_read_preempt_disable(&file_rwsem); spin_lock(&ctx->flc_lock); time_out_leases(inode, &dispose); error = check_conflicting_open(dentry, arg, lease->fl_flags); @@ -1756,7 +1756,7 @@ out_setup: lease->fl_lmops->lm_setup(lease, priv); out: spin_unlock(&ctx->flc_lock); - percpu_up_read(&file_rwsem); + percpu_up_read_preempt_enable(&file_rwsem); locks_dispose_list(&dispose); if (is_deleg) inode_unlock(inode); @@ -1779,7 +1779,7 @@ static int generic_delete_lease(struct file *filp, void *owner) return error; } - percpu_down_read(&file_rwsem); + percpu_down_read_preempt_disable(&file_rwsem); spin_lock(&ctx->flc_lock); list_for_each_entry(fl, &ctx->flc_lease, fl_list) { if (fl->fl_file == filp && @@ -1792,7 +1792,7 @@ static int generic_delete_lease(struct file *filp, void *owner) if (victim) error = fl->fl_lmops->lm_change(victim, F_UNLCK, &dispose); spin_unlock(&ctx->flc_lock); - percpu_up_read(&file_rwsem); + percpu_up_read_preempt_enable(&file_rwsem); locks_dispose_list(&dispose); return error; } -- cgit