From 28c494c5c8d425e15b7b82571e4df6d6bc34594d Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 26 Oct 2007 13:32:13 -0400 Subject: [PATCH] NFS: Prevent nfs_getattr() hang during heavy write workloads POSIX requires that ctime and mtime, as reported by the stat(2) call, reflect the activity of the most recent write(2). To that end, nfs_getattr() flushes pending dirty writes to a file before doing a GETATTR to allow the NFS server to set the file's size, ctime, and mtime properly. However, nfs_getattr() can be starved when a constant stream of application writes to a file prevents nfs_wb_nocommit() from completing. This usually results in hangs of programs doing a stat against an NFS file that is being written. "ls -l" is a common victim of this behavior. To prevent starvation, hold the file's i_mutex in nfs_getattr() to freeze applications writes temporarily so the client can more quickly obtain clean values for a file's size, mtime, and ctime. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- Reading git-format-patch failed