tree ccb21055fca86ac2657b3262ac37eb3e5c44bea0
parent b74a2f0913694556a027795d2954d30523fac4c5
author Peter Zijlstra <a.p.zijlstra@chello.nl> 1174081106 -0800
committer Linus Torvalds <torvalds@woody.linux-foundation.org> 1174098305 -0700

[PATCH] nfs: fix congestion control

The current NFS client congestion logic is severly broken, it marks the
backing device congested during each nfs_writepages() call but doesn't
mirror this in nfs_writepage() which makes for deadlocks.  Also it
implements its own waitqueue.

Replace this by a more regular congestion implementation that puts a cap on
the number of active writeback pages and uses the bdi congestion waitqueue.

Also always use an interruptible wait since it makes sense to be able to
SIGKILL the process even for mounts without 'intr'.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>