ceph: wake up writer if vmtruncate work get blocked

To write data, the writer first acquires the i_mutex, then try getting
caps. The writer may sleep while holding the i_mutex. If the MDS revokes
Fb cap in this case, vmtruncate work can't do its job because i_mutex
is locked. We should wake up the writer and let it truncate the pages.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>
This commit is contained in:
Yan, Zheng 2013-07-21 20:25:26 +08:00 committed by Sage Weil
parent ad88f23f42
commit 85ce127a9a
1 changed files with 8 additions and 1 deletions

View File

@ -1465,7 +1465,14 @@ static void ceph_vmtruncate_work(struct work_struct *work)
struct inode *inode = &ci->vfs_inode;
dout("vmtruncate_work %p\n", inode);
mutex_lock(&inode->i_mutex);
if (!mutex_trylock(&inode->i_mutex)) {
/*
* the i_mutex can be hold by a writer who is waiting for
* caps. wake up waiters, they will do pending vmtruncate.
*/
wake_up_all(&ci->i_cap_wq);
mutex_lock(&inode->i_mutex);
}
__ceph_do_pending_vmtruncate(inode);
mutex_unlock(&inode->i_mutex);
iput(inode);