From f45d34167c67b083b54690e349e77f59062ef0ea Mon Sep 17 00:00:00 2001 From: Pavel Shilovsky Date: Wed, 19 Sep 2012 06:22:43 -0700 Subject: [PATCH] CIFS: Remove spinlock dependence in brlock processing Now we need to lock/unlock a spinlock while processing brlock ops on the inode. Move brlocks of a fid to a separate list and attach all such lists to the inode. This let us not hold a spinlock. Signed-off-by: Pavel Shilovsky --- fs/cifs/cifsfs.c | 1 + fs/cifs/cifsglob.h | 18 ++++++------ fs/cifs/file.c | 73 +++++++++++++++++++++++++++------------------- 3 files changed, 53 insertions(+), 39 deletions(-) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 3a3e2fee0b3e..e958d9438505 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -233,6 +233,7 @@ cifs_alloc_inode(struct super_block *sb) to zero by the VFS */ /* cifs_inode->vfs_inode.i_flags = S_NOATIME | S_NOCMTIME;*/ INIT_LIST_HEAD(&cifs_inode->openFileList); + INIT_LIST_HEAD(&cifs_inode->llist); return &cifs_inode->vfs_inode; } diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 004672f9e16c..b2eb577b5f3f 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -890,13 +890,16 @@ struct cifs_fid { #endif }; +struct cifs_fid_locks { + struct list_head llist; + struct cifsFileInfo *cfile; /* fid that owns locks */ + struct list_head locks; /* locks held by fid above */ +}; + struct cifsFileInfo { struct list_head tlist; /* pointer to next fid owned by tcon */ struct list_head flist; /* next fid (file instance) for this inode */ - struct list_head llist; /* - * brlocks held by this fid, protected by - * lock_mutex from cifsInodeInfo structure - */ + struct cifs_fid_locks *llist; /* brlocks held by this fid */ unsigned int uid; /* allows finding which FileInfo structure */ __u32 pid; /* process id who opened file */ struct cifs_fid fid; /* file id from remote */ @@ -988,11 +991,8 @@ void cifsFileInfo_put(struct cifsFileInfo *cifs_file); struct cifsInodeInfo { bool can_cache_brlcks; - struct mutex lock_mutex; /* - * protect the field above and llist - * from every cifsFileInfo structure - * from openFileList - */ + struct list_head llist; /* locks helb by this inode */ + struct mutex lock_mutex; /* protect the fields above */ /* BB add in lists for dirty pages i.e. write caching info for oplock */ struct list_head openFileList; __u32 cifsAttrs; /* e.g. DOS archive bit, sparse, compressed, system */ diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 2421ec28df14..63963730cb28 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -245,11 +245,25 @@ cifs_new_fileinfo(struct cifs_fid *fid, struct file *file, struct inode *inode = dentry->d_inode; struct cifsInodeInfo *cinode = CIFS_I(inode); struct cifsFileInfo *cfile; + struct cifs_fid_locks *fdlocks; cfile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL); if (cfile == NULL) return cfile; + fdlocks = kzalloc(sizeof(struct cifs_fid_locks), GFP_KERNEL); + if (!fdlocks) { + kfree(cfile); + return NULL; + } + + INIT_LIST_HEAD(&fdlocks->locks); + fdlocks->cfile = cfile; + cfile->llist = fdlocks; + mutex_lock(&cinode->lock_mutex); + list_add(&fdlocks->llist, &cinode->llist); + mutex_unlock(&cinode->lock_mutex); + cfile->count = 1; cfile->pid = current->tgid; cfile->uid = current_fsuid(); @@ -257,9 +271,8 @@ cifs_new_fileinfo(struct cifs_fid *fid, struct file *file, cfile->f_flags = file->f_flags; cfile->invalidHandle = false; cfile->tlink = cifs_get_tlink(tlink); - mutex_init(&cfile->fh_mutex); INIT_WORK(&cfile->oplock_break, cifs_oplock_break); - INIT_LIST_HEAD(&cfile->llist); + mutex_init(&cfile->fh_mutex); tlink_tcon(tlink)->ses->server->ops->set_fid(cfile, fid, oplock); spin_lock(&cifs_file_list_lock); @@ -336,15 +349,18 @@ void cifsFileInfo_put(struct cifsFileInfo *cifs_file) free_xid(xid); } - /* Delete any outstanding lock records. We'll lose them when the file + /* + * Delete any outstanding lock records. We'll lose them when the file * is closed anyway. */ mutex_lock(&cifsi->lock_mutex); - list_for_each_entry_safe(li, tmp, &cifs_file->llist, llist) { + list_for_each_entry_safe(li, tmp, &cifs_file->llist->locks, llist) { list_del(&li->llist); cifs_del_lock_waiters(li); kfree(li); } + list_del(&cifs_file->llist->llist); + kfree(cifs_file->llist); mutex_unlock(&cifsi->lock_mutex); cifs_put_tlink(cifs_file->tlink); @@ -691,25 +707,24 @@ cifs_del_lock_waiters(struct cifsLockInfo *lock) } static bool -cifs_find_fid_lock_conflict(struct cifsFileInfo *cfile, __u64 offset, - __u64 length, __u8 type, struct cifsFileInfo *cur, +cifs_find_fid_lock_conflict(struct cifs_fid_locks *fdlocks, __u64 offset, + __u64 length, __u8 type, struct cifsFileInfo *cfile, struct cifsLockInfo **conf_lock) { struct cifsLockInfo *li; + struct cifsFileInfo *cur_cfile = fdlocks->cfile; struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server; - list_for_each_entry(li, &cfile->llist, llist) { + list_for_each_entry(li, &fdlocks->locks, llist) { if (offset + length <= li->offset || offset >= li->offset + li->length) continue; - else if ((type & server->vals->shared_lock_type) && - ((server->ops->compare_fids(cur, cfile) && - current->tgid == li->pid) || type == li->type)) + if ((type & server->vals->shared_lock_type) && + ((server->ops->compare_fids(cfile, cur_cfile) && + current->tgid == li->pid) || type == li->type)) continue; - else { - *conf_lock = li; - return true; - } + *conf_lock = li; + return true; } return false; } @@ -719,17 +734,15 @@ cifs_find_lock_conflict(struct cifsFileInfo *cfile, __u64 offset, __u64 length, __u8 type, struct cifsLockInfo **conf_lock) { bool rc = false; - struct cifsFileInfo *fid, *tmp; + struct cifs_fid_locks *cur; struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode); - spin_lock(&cifs_file_list_lock); - list_for_each_entry_safe(fid, tmp, &cinode->openFileList, flist) { - rc = cifs_find_fid_lock_conflict(fid, offset, length, type, + list_for_each_entry(cur, &cinode->llist, llist) { + rc = cifs_find_fid_lock_conflict(cur, offset, length, type, cfile, conf_lock); if (rc) break; } - spin_unlock(&cifs_file_list_lock); return rc; } @@ -777,7 +790,7 @@ cifs_lock_add(struct cifsFileInfo *cfile, struct cifsLockInfo *lock) { struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode); mutex_lock(&cinode->lock_mutex); - list_add_tail(&lock->llist, &cfile->llist); + list_add_tail(&lock->llist, &cfile->llist->locks); mutex_unlock(&cinode->lock_mutex); } @@ -803,7 +816,7 @@ try_again: exist = cifs_find_lock_conflict(cfile, lock->offset, lock->length, lock->type, &conf_lock); if (!exist && cinode->can_cache_brlcks) { - list_add_tail(&lock->llist, &cfile->llist); + list_add_tail(&lock->llist, &cfile->llist->locks); mutex_unlock(&cinode->lock_mutex); return rc; } @@ -937,7 +950,7 @@ cifs_push_mandatory_locks(struct cifsFileInfo *cfile) for (i = 0; i < 2; i++) { cur = buf; num = 0; - list_for_each_entry_safe(li, tmp, &cfile->llist, llist) { + list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) { if (li->type != types[i]) continue; cur->Pid = cpu_to_le16(li->pid); @@ -1279,7 +1292,7 @@ cifs_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock, for (i = 0; i < 2; i++) { cur = buf; num = 0; - list_for_each_entry_safe(li, tmp, &cfile->llist, llist) { + list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) { if (flock->fl_start > li->offset || (flock->fl_start + length) < (li->offset + li->length)) @@ -1320,7 +1333,7 @@ cifs_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock, * list to the head of the file's list. */ cifs_move_llist(&tmp_llist, - &cfile->llist); + &cfile->llist->locks); rc = stored_rc; } else /* @@ -1337,7 +1350,8 @@ cifs_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock, stored_rc = cifs_lockv(xid, tcon, cfile->fid.netfid, types[i], num, 0, buf); if (stored_rc) { - cifs_move_llist(&tmp_llist, &cfile->llist); + cifs_move_llist(&tmp_llist, + &cfile->llist->locks); rc = stored_rc; } else cifs_free_llist(&tmp_llist); @@ -1350,7 +1364,7 @@ cifs_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock, } static int -cifs_setlk(struct file *file, struct file_lock *flock, __u32 type, +cifs_setlk(struct file *file, struct file_lock *flock, __u32 type, bool wait_flag, bool posix_lck, int lock, int unlock, unsigned int xid) { @@ -1359,7 +1373,6 @@ cifs_setlk(struct file *file, struct file_lock *flock, __u32 type, struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data; struct cifs_tcon *tcon = tlink_tcon(cfile->tlink); struct TCP_Server_Info *server = tcon->ses->server; - __u16 netfid = cfile->fid.netfid; if (posix_lck) { int posix_lock_type; @@ -1376,9 +1389,9 @@ cifs_setlk(struct file *file, struct file_lock *flock, __u32 type, if (unlock == 1) posix_lock_type = CIFS_UNLCK; - rc = CIFSSMBPosixLock(xid, tcon, netfid, current->tgid, - flock->fl_start, length, NULL, - posix_lock_type, wait_flag); + rc = CIFSSMBPosixLock(xid, tcon, cfile->fid.netfid, + current->tgid, flock->fl_start, length, + NULL, posix_lock_type, wait_flag); goto out; } -- 2.34.1