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| author | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-03-17 15:59:30 (GMT) |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-03-20 17:08:26 (GMT) |
| commit | 3b3be88d67cc17d0f0ab6edaf131516793fc947e (patch) | |
| tree | 293bc2bcc7cf7a175786ec33a4e2aff8c5c7ebca /fs/nfs/write.c | |
| parent | 5ae67c4fee869c9b3c87b727a9ea511b6326b834 (diff) | |
| download | linux-3b3be88d67cc17d0f0ab6edaf131516793fc947e.tar.xz | |
NFS: Use cond_resched_lock() to reduce latencies in the commit scans
Ensure that we conditionally drop the inode->i_lock when it is safe
to do so in the commit loops.
We do so after locking the nfs_page, but before removing it from the
commit list. We can then use list_safe_reset_next to recover the loop
after the lock is retaken.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'fs/nfs/write.c')
| -rw-r--r-- | fs/nfs/write.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 628d9a6..bd93d40 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -561,7 +561,8 @@ nfs_need_commit(struct nfs_inode *nfsi) /* i_lock held by caller */ static int -nfs_scan_commit_list(struct list_head *src, struct list_head *dst, int max) +nfs_scan_commit_list(struct list_head *src, struct list_head *dst, int max, + spinlock_t *lock) { struct nfs_page *req, *tmp; int ret = 0; @@ -569,6 +570,8 @@ nfs_scan_commit_list(struct list_head *src, struct list_head *dst, int max) list_for_each_entry_safe(req, tmp, src, wb_list) { if (!nfs_lock_request(req)) continue; + if (cond_resched_lock(lock)) + list_safe_reset_next(req, tmp, wb_list); nfs_request_remove_commit_list(req); nfs_list_add_request(req, dst); ret++; @@ -596,8 +599,10 @@ nfs_scan_commit(struct inode *inode, struct list_head *dst) if (nfsi->ncommit > 0) { const int max = INT_MAX; - ret = nfs_scan_commit_list(&nfsi->commit_list, dst, max); - ret += pnfs_scan_commit_lists(inode, max - ret); + ret = nfs_scan_commit_list(&nfsi->commit_list, dst, max, + &inode->i_lock); + ret += pnfs_scan_commit_lists(inode, max - ret, + &inode->i_lock); } spin_unlock(&inode->i_lock); return ret; |