From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Chinner Subject: [RFC PATCH 2/6] xfs: use i_mmaplock on read faults Date: Thu, 8 Jan 2015 09:25:39 +1100 Message-ID: <1420669543-8093-3-git-send-email-david@fromorbit.com> References: <1420669543-8093-1-git-send-email-david@fromorbit.com> Cc: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org To: xfs@oss.sgi.com Return-path: In-Reply-To: <1420669543-8093-1-git-send-email-david@fromorbit.com> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org From: Dave Chinner Take the i_mmaplock over read page faults. These come through the ->fault callout, so we need to wrap the generic implementation with the i_mmaplock. While there, add tracepoints for the read fault as it passes through XFS. This gives us a lock order of mmap_sem -> i_mmaplock -> page_lock -> i_lock. Signed-off-by: Dave Chinner --- fs/xfs/xfs_file.c | 28 +++++++++++++++++++++++++++- fs/xfs/xfs_trace.h | 2 ++ 2 files changed, 29 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 13e974e..87535e6 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -1349,6 +1349,32 @@ xfs_file_llseek( } } +/* + * Locking for serialisation of IO during page faults. This results in a lock + * ordering of: + * + * mmap_sem (MM) + * i_mmap_lock (XFS - truncate serialisation) + * page_lock (MM) + * i_lock (XFS - extent map serialisation) + */ +STATIC int +xfs_filemap_fault( + struct vm_area_struct *vma, + struct vm_fault *vmf) +{ + struct xfs_inode *ip = XFS_I(vma->vm_file->f_mapping->host); + int error; + + trace_xfs_filemap_fault(ip); + + xfs_ilock(ip, XFS_MMAPLOCK_SHARED); + error = filemap_fault(vma, vmf); + xfs_iunlock(ip, XFS_MMAPLOCK_SHARED); + + return error; +} + const struct file_operations xfs_file_operations = { .llseek = xfs_file_llseek, .read = new_sync_read, @@ -1381,7 +1407,7 @@ const struct file_operations xfs_dir_file_operations = { }; static const struct vm_operations_struct xfs_file_vm_ops = { - .fault = filemap_fault, + .fault = xfs_filemap_fault, .map_pages = filemap_map_pages, .page_mkwrite = xfs_vm_page_mkwrite, .remap_pages = generic_file_remap_pages, diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index 51372e3..c496153 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -685,6 +685,8 @@ DEFINE_INODE_EVENT(xfs_inode_set_eofblocks_tag); DEFINE_INODE_EVENT(xfs_inode_clear_eofblocks_tag); DEFINE_INODE_EVENT(xfs_inode_free_eofblocks_invalid); +DEFINE_INODE_EVENT(xfs_filemap_fault); + DECLARE_EVENT_CLASS(xfs_iref_class, TP_PROTO(struct xfs_inode *ip, unsigned long caller_ip), TP_ARGS(ip, caller_ip), -- 2.0.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id 46C417FA6 for ; Wed, 7 Jan 2015 16:26:13 -0600 (CST) Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by relay2.corp.sgi.com (Postfix) with ESMTP id 35D35304051 for ; Wed, 7 Jan 2015 14:26:09 -0800 (PST) Received: from ipmail06.adl2.internode.on.net (ipmail06.adl2.internode.on.net [150.101.137.129]) by cuda.sgi.com with ESMTP id pD26NY0z9q9PdCuN for ; Wed, 07 Jan 2015 14:26:08 -0800 (PST) From: Dave Chinner Subject: [RFC PATCH 2/6] xfs: use i_mmaplock on read faults Date: Thu, 8 Jan 2015 09:25:39 +1100 Message-Id: <1420669543-8093-3-git-send-email-david@fromorbit.com> In-Reply-To: <1420669543-8093-1-git-send-email-david@fromorbit.com> References: <1420669543-8093-1-git-send-email-david@fromorbit.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: xfs@oss.sgi.com Cc: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org From: Dave Chinner Take the i_mmaplock over read page faults. These come through the ->fault callout, so we need to wrap the generic implementation with the i_mmaplock. While there, add tracepoints for the read fault as it passes through XFS. This gives us a lock order of mmap_sem -> i_mmaplock -> page_lock -> i_lock. Signed-off-by: Dave Chinner --- fs/xfs/xfs_file.c | 28 +++++++++++++++++++++++++++- fs/xfs/xfs_trace.h | 2 ++ 2 files changed, 29 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 13e974e..87535e6 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -1349,6 +1349,32 @@ xfs_file_llseek( } } +/* + * Locking for serialisation of IO during page faults. This results in a lock + * ordering of: + * + * mmap_sem (MM) + * i_mmap_lock (XFS - truncate serialisation) + * page_lock (MM) + * i_lock (XFS - extent map serialisation) + */ +STATIC int +xfs_filemap_fault( + struct vm_area_struct *vma, + struct vm_fault *vmf) +{ + struct xfs_inode *ip = XFS_I(vma->vm_file->f_mapping->host); + int error; + + trace_xfs_filemap_fault(ip); + + xfs_ilock(ip, XFS_MMAPLOCK_SHARED); + error = filemap_fault(vma, vmf); + xfs_iunlock(ip, XFS_MMAPLOCK_SHARED); + + return error; +} + const struct file_operations xfs_file_operations = { .llseek = xfs_file_llseek, .read = new_sync_read, @@ -1381,7 +1407,7 @@ const struct file_operations xfs_dir_file_operations = { }; static const struct vm_operations_struct xfs_file_vm_ops = { - .fault = filemap_fault, + .fault = xfs_filemap_fault, .map_pages = filemap_map_pages, .page_mkwrite = xfs_vm_page_mkwrite, .remap_pages = generic_file_remap_pages, diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index 51372e3..c496153 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -685,6 +685,8 @@ DEFINE_INODE_EVENT(xfs_inode_set_eofblocks_tag); DEFINE_INODE_EVENT(xfs_inode_clear_eofblocks_tag); DEFINE_INODE_EVENT(xfs_inode_free_eofblocks_invalid); +DEFINE_INODE_EVENT(xfs_filemap_fault); + DECLARE_EVENT_CLASS(xfs_iref_class, TP_PROTO(struct xfs_inode *ip, unsigned long caller_ip), TP_ARGS(ip, caller_ip), -- 2.0.0 _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs