From b766fc83fccdab67c1cbe5fce969394ae94c686c Mon Sep 17 00:00:00 2001
From: Amir Goldstein <amir73il@gmail.com>
Date: Tue, 10 Aug 2021 18:12:18 +0300
Subject: [PATCH] fsnotify: count s_fsnotify_inode_refs for attached connectors
References: bsc#1190120 (Fsnotify functional and performance backports)
Patch-mainline: v5.15-rc1
Git-commit: 11fa333b58ba1518e7c69fafb6513a0117f8fe33
Instead of incrementing s_fsnotify_inode_refs when detaching connector
from inode, increment it earlier when attaching connector to inode.
Next patch is going to use s_fsnotify_inode_refs to count all objects
with attached connectors.
Link: https://lore.kernel.org/r/20210810151220.285179-3-amir73il@gmail.com
Reviewed-by: Matthew Bobrowski <repnop@google.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mel Gorman <mgorman@suse.de>
---
fs/notify/mark.c | 29 ++++++++++++++++++-----------
1 file changed, 18 insertions(+), 11 deletions(-)
diff --git a/fs/notify/mark.c b/fs/notify/mark.c
index 80459db58f63..2d8c46e1167d 100644
--- a/fs/notify/mark.c
+++ b/fs/notify/mark.c
@@ -169,6 +169,21 @@ static void fsnotify_connector_destroy_workfn(struct work_struct *work)
}
}
+static void fsnotify_get_inode_ref(struct inode *inode)
+{
+ ihold(inode);
+ atomic_long_inc(&inode->i_sb->s_fsnotify_inode_refs);
+}
+
+static void fsnotify_put_inode_ref(struct inode *inode)
+{
+ struct super_block *sb = inode->i_sb;
+
+ iput(inode);
+ if (atomic_long_dec_and_test(&sb->s_fsnotify_inode_refs))
+ wake_up_var(&sb->s_fsnotify_inode_refs);
+}
+
static void *fsnotify_detach_connector_from_object(
struct fsnotify_mark_connector *conn,
unsigned int *type)
@@ -182,7 +197,6 @@ static void *fsnotify_detach_connector_from_object(
if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) {
inode = fsnotify_conn_inode(conn);
inode->i_fsnotify_mask = 0;
- atomic_long_inc(&inode->i_sb->s_fsnotify_inode_refs);
} else if (conn->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) {
fsnotify_conn_mount(conn)->mnt_fsnotify_mask = 0;
} else if (conn->type == FSNOTIFY_OBJ_TYPE_SB) {
@@ -209,19 +223,12 @@ static void fsnotify_final_mark_destroy(struct fsnotify_mark *mark)
/* Drop object reference originally held by a connector */
static void fsnotify_drop_object(unsigned int type, void *objp)
{
- struct inode *inode;
- struct super_block *sb;
-
if (!objp)
return;
/* Currently only inode references are passed to be dropped */
if (WARN_ON_ONCE(type != FSNOTIFY_OBJ_TYPE_INODE))
return;
- inode = objp;
- sb = inode->i_sb;
- iput(inode);
- if (atomic_long_dec_and_test(&sb->s_fsnotify_inode_refs))
- wake_up_var(&sb->s_fsnotify_inode_refs);
+ fsnotify_put_inode_ref(objp);
}
void fsnotify_put_mark(struct fsnotify_mark *mark)
@@ -495,7 +502,7 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp,
}
if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) {
inode = fsnotify_conn_inode(conn);
- ihold(inode);
+ fsnotify_get_inode_ref(inode);
}
/*
@@ -505,7 +512,7 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp,
if (cmpxchg(connp, NULL, conn)) {
/* Someone else created list structure for us */
if (inode)
- iput(inode);
+ fsnotify_put_inode_ref(inode);
kmem_cache_free(fsnotify_mark_connector_cachep, conn);
}