aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorAlan D. Brunelle <alan.brunelle@hp.com>2009-08-07 12:01:08 -0400
committerJens Axboe <jens.axboe@oracle.com>2009-08-12 18:50:08 +0200
commit39cbb602b543e477df71dca84b5b2e36f8bd29fc (patch)
tree70639084b6a04ce428cecbaa5fa30c2d71d5ff33
parent7cb7beb31aa3d941833b6a6e553687422c31e4b6 (diff)
Remove double removal of blktrace directory
commit fd51d251e4cdb21f68e9dbc4336514d64a105a79 Author: Stefan Raspl <raspl@linux.vnet.ibm.com> Date: Tue May 19 09:59:08 2009 +0200 blktrace: remove debugfs entries on bad path added in an explicit invocation of debugfs_remove for bt->dir, in blk_remove_buf_file_callback we are also getting the directory removed. On occasion I am seeing memory corruption that I have bisected down to this commit. [The testing involves a (long) series of I/O benchmarks with blktrace invoked around the actual runs.] I believe that this committed patch is correct, but the problem actually lies in the code in blk_remove_buf_file_callback. With this patch I am able to consistently get complete runs whereas previously I could not get a single run to complete. The first part of the patch simply moves the debugfs_remove below the relay_close: the relay_close call will remove files under bt->dir, and so we should not remove the directory until all the files we created have been removed. (Note: This is not sufficient to fix the problem - the file system code has ref counts on the directoy, so our invocation does not cause the directory to actually be removed. Nonetheless, we should not rely upon that feature.) Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
-rw-r--r--kernel/trace/blktrace.c12
1 files changed, 1 insertions, 11 deletions
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 1090b0aed9b..7a34cb563fe 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -267,8 +267,8 @@ static void blk_trace_free(struct blk_trace *bt)
{
debugfs_remove(bt->msg_file);
debugfs_remove(bt->dropped_file);
- debugfs_remove(bt->dir);
relay_close(bt->rchan);
+ debugfs_remove(bt->dir);
free_percpu(bt->sequence);
free_percpu(bt->msg_data);
kfree(bt);
@@ -378,18 +378,8 @@ static int blk_subbuf_start_callback(struct rchan_buf *buf, void *subbuf,
static int blk_remove_buf_file_callback(struct dentry *dentry)
{
- struct dentry *parent = dentry->d_parent;
debugfs_remove(dentry);
- /*
- * this will fail for all but the last file, but that is ok. what we
- * care about is the top level buts->name directory going away, when
- * the last trace file is gone. Then we don't have to rmdir() that
- * manually on trace stop, so it nicely solves the issue with
- * force killing of running traces.
- */
-
- debugfs_remove(parent);
return 0;
}