diff options
| author | Wu Fengguang <fengguang.wu@intel.com> | 2008-12-23 15:21:30 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-01-18 10:35:44 -0800 |
| commit | fdec10829d87dfa334b6584b6b8882a36b0b0b41 (patch) | |
| tree | 35248718472df8b4099732afd54a88affa35e2d5 /net/unix/garbage.c | |
| parent | fc6be7e5f3c5c9be7a48fa540a1da7a8bb7d033e (diff) | |
nfs: remove redundant tests on reading new pages
commit 136221fc3219b3805c48db5da065e8e3467175d4 upstream.
aops->readpages() and its NFS helper readpage_async_filler() will only
be called to do readahead I/O for newly allocated pages. So it's not
necessary to test for the always 0 dirty/uptodate page flags.
The removal of nfs_wb_page() call also fixes a readahead bug: the NFS
readahead has been synchronous since 2.6.23, because that call will
clear PG_readahead, which is the reminder for asynchronous readahead.
More background: the PG_readahead page flag is shared with PG_reclaim,
one for read path and the other for write path. clear_page_dirty_for_io()
unconditionally clears PG_readahead to prevent possible readahead residuals,
assuming itself to be always called in the write path. However, NFS is one
and the only exception in that it _always_ calls clear_page_dirty_for_io()
in the read path, i.e. for readpages()/readpage().
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Wu Fengguang <wfg@linux.intel.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'net/unix/garbage.c')
0 files changed, 0 insertions, 0 deletions