From patchwork Tue Aug 18 18:07:00 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [3/5] cifs: clean up cifs_oplock_thread loop From: Jeff Layton X-Patchwork-Id: 31583 Message-Id: <1250618822-6131-4-git-send-email-jlayton@redhat.com> To: smfrench@gmail.com Cc: linux-cifs-client@lists.samba.org Date: Tue, 18 Aug 2009 14:07:00 -0400 Minor cleanups and optimizations mostly. Also fix it so that if a kthread_stop races in at the right time, it won't make the thread sleep unnecessarily for 39s. Signed-off-by: Jeff Layton Acked-by: Shirish Pargaonkar --- fs/cifs/cifsfs.c | 66 +++++++++++++++++++++++++++++------------------------ 1 files changed, 36 insertions(+), 30 deletions(-) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 7ce8dcd..2fcc722 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -972,10 +972,10 @@ cifs_destroy_mids(void) static int cifs_oplock_thread(void *dummyarg) { - struct oplock_q_entry *oplock_item; - struct cifsTconInfo *pTcon; + struct oplock_q_entry *oplock; + struct cifsTconInfo *tcon; struct inode *inode; - __u16 netfid; + struct cifsInodeInfo *cifsi; int rc, waitrc = 0; set_freezable(); @@ -984,34 +984,30 @@ static int cifs_oplock_thread(void *dummyarg) continue; spin_lock(&cifs_oplock_lock); - if (list_empty(&cifs_oplock_list)) { + while(!list_empty(&cifs_oplock_list)) { + oplock = list_entry(cifs_oplock_list.next, + struct oplock_q_entry, qhead); + list_del(&oplock->qhead); spin_unlock(&cifs_oplock_lock); - set_current_state(TASK_INTERRUPTIBLE); - schedule_timeout(39*HZ); - } else { - oplock_item = list_entry(cifs_oplock_list.next, - struct oplock_q_entry, qhead); + cFYI(1, ("found oplock item to write out")); - pTcon = oplock_item->tcon; - inode = oplock_item->pinode; - netfid = oplock_item->netfid; - list_del(&oplock_item->qhead); - spin_unlock(&cifs_oplock_lock); - kmem_cache_free(cifs_oplock_cachep, oplock_item); + tcon = oplock->tcon; + inode = oplock->pinode; /* can not grab inode sem here since it would deadlock when oplock received on delete since vfs_unlink holds the i_mutex across the call */ /* mutex_lock(&inode->i_mutex);*/ + cifsi = CIFS_I(inode); if (S_ISREG(inode->i_mode)) { #ifdef CONFIG_CIFS_EXPERIMENTAL - if (CIFS_I(inode)->clientCanCacheAll == 0) + if (cifsi->clientCanCacheAll == 0) break_lease(inode, FMODE_READ); - else if (CIFS_I(inode)->clientCanCacheRead == 0) + else if (cifsi->clientCanCacheRead == 0) break_lease(inode, FMODE_WRITE); #endif rc = filemap_fdatawrite(inode->i_mapping); - if (CIFS_I(inode)->clientCanCacheRead == 0) { + if (cifsi->clientCanCacheRead == 0) { waitrc = filemap_fdatawait( inode->i_mapping); invalidate_remote_inode(inode); @@ -1022,27 +1018,37 @@ static int cifs_oplock_thread(void *dummyarg) rc = 0; /* mutex_unlock(&inode->i_mutex);*/ if (rc) - CIFS_I(inode)->write_behind_rc = rc; + cifsi->write_behind_rc = rc; cFYI(1, ("Oplock flush inode %p rc %d", inode, rc)); - /* releasing stale oplock after recent reconnect - of smb session using a now incorrect file - handle is not a data integrity issue but do - not bother sending an oplock release if session - to server still is disconnected since oplock - already released by the server in that case */ - if (!pTcon->need_reconnect) { - rc = CIFSSMBLock(0, pTcon, netfid, + /* + * releasing stale oplock after recent reconnect + * of smb session using a now incorrect file + * handle is not a data integrity issue but do + * not bother sending an oplock release if session + * to server still is disconnected since oplock + * already released by the server in that case + */ + if (!tcon->need_reconnect) { + rc = CIFSSMBLock(0, tcon, oplock->netfid, 0 /* len */ , 0 /* offset */, 0, 0, LOCKING_ANDX_OPLOCK_RELEASE, false /* wait flag */); cFYI(1, ("Oplock release rc = %d", rc)); } - cifs_put_tcon(pTcon); - set_current_state(TASK_INTERRUPTIBLE); - schedule_timeout(1); /* yield in case q were corrupt */ + cifs_put_tcon(tcon); + kmem_cache_free(cifs_oplock_cachep, oplock); + spin_lock(&cifs_oplock_lock); + } + spin_unlock(&cifs_oplock_lock); + set_current_state(TASK_INTERRUPTIBLE); + if (kthread_should_stop()) { + set_current_state(TASK_RUNNING); + break; } + /* FIXME: Why 39s here? This should be a named constant. */ + schedule_timeout(39*HZ); } while (!kthread_should_stop()); return 0;