NFS: Reduce time spent holding the i_mutex during fallocate()

At the very least, we should not be taking the i_mutex until after
checking if the server even supports ALLOCATE or DEALLOCATE, allowing
v4.0 or v4.1 to exit without potentially waiting on a lock.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This commit is contained in:
Anna Schumaker 2015-03-16 14:06:24 -04:00 committed by Trond Myklebust
parent 9a51940bf6
commit f830f7ddd9
2 changed files with 10 additions and 7 deletions

View File

@ -96,9 +96,13 @@ int nfs42_proc_allocate(struct file *filep, loff_t offset, loff_t len)
if (!nfs_server_capable(inode, NFS_CAP_ALLOCATE)) if (!nfs_server_capable(inode, NFS_CAP_ALLOCATE))
return -EOPNOTSUPP; return -EOPNOTSUPP;
mutex_lock(&inode->i_mutex);
err = nfs42_proc_fallocate(&msg, filep, offset, len); err = nfs42_proc_fallocate(&msg, filep, offset, len);
if (err == -EOPNOTSUPP) if (err == -EOPNOTSUPP)
NFS_SERVER(inode)->caps &= ~NFS_CAP_ALLOCATE; NFS_SERVER(inode)->caps &= ~NFS_CAP_ALLOCATE;
mutex_unlock(&inode->i_mutex);
return err; return err;
} }
@ -114,11 +118,15 @@ int nfs42_proc_deallocate(struct file *filep, loff_t offset, loff_t len)
return -EOPNOTSUPP; return -EOPNOTSUPP;
nfs_wb_all(inode); nfs_wb_all(inode);
mutex_lock(&inode->i_mutex);
err = nfs42_proc_fallocate(&msg, filep, offset, len); err = nfs42_proc_fallocate(&msg, filep, offset, len);
if (err == 0) if (err == 0)
truncate_pagecache_range(inode, offset, (offset + len) -1); truncate_pagecache_range(inode, offset, (offset + len) -1);
if (err == -EOPNOTSUPP) if (err == -EOPNOTSUPP)
NFS_SERVER(inode)->caps &= ~NFS_CAP_DEALLOCATE; NFS_SERVER(inode)->caps &= ~NFS_CAP_DEALLOCATE;
mutex_unlock(&inode->i_mutex);
return err; return err;
} }

View File

@ -158,14 +158,9 @@ static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t
if (ret < 0) if (ret < 0)
return ret; return ret;
mutex_lock(&inode->i_mutex);
if (mode & FALLOC_FL_PUNCH_HOLE) if (mode & FALLOC_FL_PUNCH_HOLE)
ret = nfs42_proc_deallocate(filep, offset, len); return nfs42_proc_deallocate(filep, offset, len);
else return nfs42_proc_allocate(filep, offset, len);
ret = nfs42_proc_allocate(filep, offset, len);
mutex_unlock(&inode->i_mutex);
return ret;
} }
#endif /* CONFIG_NFS_V4_2 */ #endif /* CONFIG_NFS_V4_2 */