linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Nick Piggin <npiggin@suse.de>
To: Andrew Morton <akpm@linux-foundation.org>,
	Jan Kara <jack@suse.cz>,
	linux-fsdevel@vger.kernel.org
Cc: ttb@tentacle.dhs.org
Subject: [rfc][patch 2/2] inotify: remove debug code
Date: Mon, 3 Dec 2007 07:48:05 +0100	[thread overview]
Message-ID: <20071203064805.GC22451@wotan.suse.de> (raw)
In-Reply-To: <20071203064635.GB22451@wotan.suse.de>


The inotify debugging code is supposed to verify that the
DCACHE_INOTIFY_PARENT_WATCHED scalability optimisation does not result in
notifications getting lost nor extra needless locking generated.

Unfortunately there are also some races in the debugging code. And it isn't
very good at finding problems anyway. So remove it for now.

Signed-off-by: Nick Piggin <npiggin@suse.de>
---
Index: linux-2.6/fs/dcache.c
===================================================================
--- linux-2.6.orig/fs/dcache.c
+++ linux-2.6/fs/dcache.c
@@ -1408,9 +1408,6 @@ void d_delete(struct dentry * dentry)
 	if (atomic_read(&dentry->d_count) == 1) {
 		dentry_iput(dentry);
 		fsnotify_nameremove(dentry, isdir);
-
-		/* remove this and other inotify debug checks after 2.6.18 */
-		dentry->d_flags &= ~DCACHE_INOTIFY_PARENT_WATCHED;
 		return;
 	}
 
Index: linux-2.6/fs/inotify.c
===================================================================
--- linux-2.6.orig/fs/inotify.c
+++ linux-2.6/fs/inotify.c
@@ -168,20 +168,14 @@ static void set_dentry_child_flags(struc
 		struct dentry *child;
 
 		list_for_each_entry(child, &alias->d_subdirs, d_u.d_child) {
-			if (!child->d_inode) {
-				WARN_ON(child->d_flags & DCACHE_INOTIFY_PARENT_WATCHED);
+			if (!child->d_inode)
 				continue;
-			}
+
 			spin_lock(&child->d_lock);
-			if (watched) {
-				WARN_ON(child->d_flags &
-						DCACHE_INOTIFY_PARENT_WATCHED);
+			if (watched)
 				child->d_flags |= DCACHE_INOTIFY_PARENT_WATCHED;
-			} else {
-				WARN_ON(!(child->d_flags &
-					DCACHE_INOTIFY_PARENT_WATCHED));
-				child->d_flags&=~DCACHE_INOTIFY_PARENT_WATCHED;
-			}
+			else
+				child->d_flags &=~DCACHE_INOTIFY_PARENT_WATCHED;
 			spin_unlock(&child->d_lock);
 		}
 	}
@@ -253,7 +247,6 @@ void inotify_d_instantiate(struct dentry
 	if (!inode)
 		return;
 
-	WARN_ON(entry->d_flags & DCACHE_INOTIFY_PARENT_WATCHED);
 	spin_lock(&entry->d_lock);
 	parent = entry->d_parent;
 	if (parent->d_inode && inotify_inode_watched(parent->d_inode))

      reply	other threads:[~2007-12-03  6:48 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-12-03  6:46 [rfc][patch 1/2] inotify: fix race Nick Piggin
2007-12-03  6:48 ` Nick Piggin [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20071203064805.GC22451@wotan.suse.de \
    --to=npiggin@suse.de \
    --cc=akpm@linux-foundation.org \
    --cc=jack@suse.cz \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=ttb@tentacle.dhs.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).