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author | Jeff Layton <jlayton@redhat.com> | 2011-03-25 16:25:57 -0400 |
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committer | Steve French <sfrench@us.ibm.com> | 2011-04-12 00:56:00 +0000 |
commit | 2b6c26a0a62cc0bab0ad487533d5581d7c293fef (patch) | |
tree | 9d1d9b7c3313c43ac580432dbd5ffcceef825d24 | |
parent | 8679b0dba7cb98842cbe37f61ef05ef64106334c (diff) | |
download | op-kernel-dev-2b6c26a0a62cc0bab0ad487533d5581d7c293fef.zip op-kernel-dev-2b6c26a0a62cc0bab0ad487533d5581d7c293fef.tar.gz |
cifs: set ra_pages in backing_dev_info
Commit 522440ed made cifs set backing_dev_info on the mapping attached
to new inodes. This change caused a fairly significant read performance
regression, as cifs started doing page-sized reads exclusively.
By virtue of the fact that they're allocated as part of cifs_sb_info by
kzalloc, the ra_pages on cifs BDIs get set to 0, which prevents any
readahead. This forces the normal read codepaths to use readpage instead
of readpages causing a four-fold increase in the number of read calls
with the default rsize.
Fix it by setting ra_pages in the BDI to the same value as that in the
default_backing_dev_info.
Fixes https://bugzilla.kernel.org/show_bug.cgi?id=31662
Cc: stable@kernel.org
Reported-and-Tested-by: Till <till2.schaefer@uni-dortmund.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
-rw-r--r-- | fs/cifs/cifsfs.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 0e0cc60..e3352a1 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -130,6 +130,7 @@ cifs_read_super(struct super_block *sb, void *data, kfree(cifs_sb); return rc; } + cifs_sb->bdi.ra_pages = default_backing_dev_info.ra_pages; #ifdef CONFIG_CIFS_DFS_UPCALL /* copy mount params to sb for use in submounts */ |