From: Stephen Brennan <stephen.s.brennan@oracle.com>
To: Jan Kara <jack@suse.cz>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
Al Viro <viro@zeniv.linux.org.uk>,
Stephen Brennan <stephen.s.brennan@oracle.com>,
Amir Goldstein <amir73il@gmail.com>
Subject: [PATCH v4 3/5] dnotify: move fsnotify_recalc_mask() outside spinlock
Date: Fri, 11 Nov 2022 14:06:12 -0800 [thread overview]
Message-ID: <20221111220614.991928-4-stephen.s.brennan@oracle.com> (raw)
In-Reply-To: <20221111220614.991928-1-stephen.s.brennan@oracle.com>
In order to allow sleeping during fsnotify_recalc_mask(), we need to
ensure no callers are holding a spinlock.
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
---
fs/notify/dnotify/dnotify.c | 28 +++++++++++++++++++---------
1 file changed, 19 insertions(+), 9 deletions(-)
diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c
index 190aa717fa32..a9f05b3cf5ea 100644
--- a/fs/notify/dnotify/dnotify.c
+++ b/fs/notify/dnotify/dnotify.c
@@ -58,10 +58,10 @@ struct dnotify_mark {
* dnotify cares about for that inode may change. This function runs the
* list of everything receiving dnotify events about this directory and calculates
* the set of all those events. After it updates what dnotify is interested in
- * it calls the fsnotify function so it can update the set of all events relevant
- * to this inode.
+ * it returns true if fsnotify_recalc_mask() should be called to update the set
+ * of all events related to this inode.
*/
-static void dnotify_recalc_inode_mask(struct fsnotify_mark *fsn_mark)
+static bool dnotify_recalc_inode_mask(struct fsnotify_mark *fsn_mark)
{
__u32 new_mask = 0;
struct dnotify_struct *dn;
@@ -74,10 +74,9 @@ static void dnotify_recalc_inode_mask(struct fsnotify_mark *fsn_mark)
for (dn = dn_mark->dn; dn != NULL; dn = dn->dn_next)
new_mask |= (dn->dn_mask & ~FS_DN_MULTISHOT);
if (fsn_mark->mask == new_mask)
- return;
+ return false;
fsn_mark->mask = new_mask;
-
- fsnotify_recalc_mask(fsn_mark->connector);
+ return true;
}
/*
@@ -97,6 +96,7 @@ static int dnotify_handle_event(struct fsnotify_mark *inode_mark, u32 mask,
struct dnotify_struct **prev;
struct fown_struct *fown;
__u32 test_mask = mask & ~FS_EVENT_ON_CHILD;
+ bool recalc = false;
/* not a dir, dnotify doesn't care */
if (!dir && !(mask & FS_ISDIR))
@@ -118,12 +118,15 @@ static int dnotify_handle_event(struct fsnotify_mark *inode_mark, u32 mask,
else {
*prev = dn->dn_next;
kmem_cache_free(dnotify_struct_cache, dn);
- dnotify_recalc_inode_mask(inode_mark);
+ recalc = dnotify_recalc_inode_mask(inode_mark);
}
}
spin_unlock(&inode_mark->lock);
+ if (recalc)
+ fsnotify_recalc_mask(inode_mark->connector);
+
return 0;
}
@@ -158,6 +161,7 @@ void dnotify_flush(struct file *filp, fl_owner_t id)
struct dnotify_struct **prev;
struct inode *inode;
bool free = false;
+ bool recalc = false;
inode = file_inode(filp);
if (!S_ISDIR(inode->i_mode))
@@ -176,7 +180,7 @@ void dnotify_flush(struct file *filp, fl_owner_t id)
if ((dn->dn_owner == id) && (dn->dn_filp == filp)) {
*prev = dn->dn_next;
kmem_cache_free(dnotify_struct_cache, dn);
- dnotify_recalc_inode_mask(fsn_mark);
+ recalc = dnotify_recalc_inode_mask(fsn_mark);
break;
}
prev = &dn->dn_next;
@@ -184,6 +188,9 @@ void dnotify_flush(struct file *filp, fl_owner_t id)
spin_unlock(&fsn_mark->lock);
+ if (recalc)
+ fsnotify_recalc_mask(fsn_mark->connector);
+
/* nothing else could have found us thanks to the dnotify_groups
mark_mutex */
if (dn_mark->dn == NULL) {
@@ -268,6 +275,7 @@ int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
struct file *f;
int destroy = 0, error = 0;
__u32 mask;
+ bool recalc = false;
/* we use these to tell if we need to kfree */
new_fsn_mark = NULL;
@@ -377,9 +385,11 @@ int fcntl_dirnotify(int fd, struct file *filp, unsigned long arg)
else if (error == -EEXIST)
error = 0;
- dnotify_recalc_inode_mask(fsn_mark);
+ recalc = dnotify_recalc_inode_mask(fsn_mark);
out:
spin_unlock(&fsn_mark->lock);
+ if (recalc)
+ fsnotify_recalc_mask(fsn_mark->connector);
if (destroy)
fsnotify_detach_mark(fsn_mark);
--
2.34.1
next prev parent reply other threads:[~2022-11-11 22:06 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-13 22:27 [RFC] fsnotify: allow sleepable child dentry flag update Stephen Brennan
2022-10-13 23:51 ` Al Viro
2022-11-01 21:47 ` Stephen Brennan
2022-10-14 8:01 ` Amir Goldstein
2022-10-17 7:59 ` Stephen Brennan
2022-10-17 11:44 ` Amir Goldstein
2022-10-17 16:59 ` Stephen Brennan
2022-10-17 17:42 ` Amir Goldstein
2022-10-17 9:09 ` Jan Kara
2022-10-18 4:12 ` [PATCH 0/2] fsnotify: fix softlockups iterating over d_subdirs Stephen Brennan
2022-10-18 4:12 ` [PATCH 1/2] fsnotify: Protect i_fsnotify_mask and child flags with inode rwsem Stephen Brennan
2022-10-18 7:39 ` Amir Goldstein
2022-10-21 0:33 ` Stephen Brennan
2022-10-21 7:22 ` Amir Goldstein
2022-10-18 4:12 ` [PATCH 2/2] fsnotify: allow sleepable child flag update Stephen Brennan
2022-10-18 5:36 ` Amir Goldstein
2022-10-27 7:50 ` kernel test robot
2022-10-27 8:44 ` Yujie Liu
2022-10-27 22:12 ` Stephen Brennan
2022-10-18 8:07 ` [PATCH 0/2] fsnotify: fix softlockups iterating over d_subdirs Amir Goldstein
2022-10-18 23:52 ` Stephen Brennan
2022-10-19 5:33 ` Amir Goldstein
2022-10-27 22:06 ` Stephen Brennan
2022-10-28 8:58 ` Amir Goldstein
2022-10-21 1:03 ` [PATCH v2 0/3] " Stephen Brennan
2022-10-21 1:03 ` [PATCH v2 1/3] fsnotify: Use d_find_any_alias to get dentry associated with inode Stephen Brennan
2022-10-21 9:25 ` Amir Goldstein
2022-10-21 1:03 ` [PATCH v2 2/3] fsnotify: Protect i_fsnotify_mask and child flags with inode rwsem Stephen Brennan
2022-10-21 4:01 ` kernel test robot
2022-10-21 8:22 ` Amir Goldstein
2022-10-21 9:18 ` Amir Goldstein
2022-10-25 18:02 ` Stephen Brennan
2022-10-26 5:41 ` Amir Goldstein
2022-10-21 9:17 ` Christian Brauner
2022-10-21 9:21 ` Amir Goldstein
2022-10-21 1:03 ` [PATCH v2 3/3] fsnotify: allow sleepable child flag update Stephen Brennan
2022-10-28 0:10 ` [PATCH v3 0/3] fsnotify: fix softlockups iterating over d_subdirs Stephen Brennan
2022-10-28 0:10 ` [PATCH v3 1/3] fsnotify: Use d_find_any_alias to get dentry associated with inode Stephen Brennan
2022-11-10 1:12 ` Stephen Brennan
2022-10-28 0:10 ` [PATCH v3 2/3] fsnotify: Protect i_fsnotify_mask and child flags with inode rwsem Stephen Brennan
2022-10-28 9:11 ` Amir Goldstein
2022-11-10 0:03 ` kernel test robot
2022-11-10 1:06 ` Stephen Brennan
2022-10-28 0:10 ` [PATCH v3 3/3] fsnotify: allow sleepable child flag update Stephen Brennan
2022-10-28 9:32 ` Amir Goldstein
2022-11-01 21:25 ` Stephen Brennan
2022-11-01 17:51 ` [PATCH v3 0/3] fsnotify: fix softlockups iterating over d_subdirs Jan Kara
2022-11-01 20:48 ` Stephen Brennan
2022-11-02 8:55 ` Amir Goldstein
2022-11-10 20:04 ` Stephen Brennan
2022-11-02 17:52 ` Jan Kara
2022-11-04 23:33 ` Stephen Brennan
2022-11-07 11:56 ` Jan Kara
2022-11-11 22:06 ` [PATCH v4 0/5] " Stephen Brennan
2022-11-11 22:06 ` [PATCH v4 1/5] fsnotify: clear PARENT_WATCHED flags lazily Stephen Brennan
2022-11-11 22:06 ` [PATCH v4 2/5] fsnotify: Use d_find_any_alias to get dentry associated with inode Stephen Brennan
2022-11-12 8:53 ` Amir Goldstein
2022-11-11 22:06 ` Stephen Brennan [this message]
2022-11-12 9:06 ` [PATCH v4 3/5] dnotify: move fsnotify_recalc_mask() outside spinlock Amir Goldstein
2022-11-11 22:06 ` [PATCH v4 4/5] fsnotify: allow sleepable child flag update Stephen Brennan
2022-11-12 10:00 ` Amir Goldstein
2022-11-15 7:10 ` kernel test robot
2022-11-11 22:06 ` [PATCH v4 5/5] fsnotify: require inode lock held during " Stephen Brennan
2022-11-12 9:42 ` Amir Goldstein
2022-11-11 22:08 ` [PATCH v4 0/5] fsnotify: fix softlockups iterating over d_subdirs Stephen Brennan
2022-11-22 11:50 ` Jan Kara
2022-11-22 14:03 ` Amir Goldstein
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