==> Regarding Re: [patch] get rid of is_mounted checks in cache_clean; Ian Kent
<[EMAIL PROTECTED]> adds:
raven> On Mon, 25 Apr 2005, Jeff Moyer wrote:
>> Hi, Ian,
>>
>> I'm not sure what purpose the following check serves in the cache_clean
>> function:
>>
>> if (is_mounted(_PATH_MOUNTED, path)) { free(path); continue; }
>>
>> In the event that the map was updated, we signal the daemon to do a
>> re-read of the entire map. If the mount finishes before the daemon is
>> able to process this signal, we end up not pruning the old entry for the
>> given path. Now, because we append entries to the cache, we end up with
>> the stale entry first, followed by the updated entry. This means that
>> subsequent lookups will give the old entry.
raven> This was originally meant to stop busy (currently mounted) entries
raven> from disappearing from the cache.
raven> I'll check whether this is actually needed and get back.
raven> One thing that comes to mind is that the direct mount rework design
raven> might need this.
Well, unfortunately I cannot comment on that. We had have a very precise
definite of what it means to be in the cache, then, if there are to be
side-effects of removing entries.
Anyway, the patch I sent was somewhat incomplete. Look at this:
if (me->age < age) {
pred->next = me->next;
free(me->key);
free(me->mapent);
free(me);
me = pred;
rmdir_path(path);
}
The rmdir_path is unneeded, and I would argue has no business being here.
It is the job of the umount_multi code to clean up the directory tree, not
the cache code. Lucky for us, the umount_multi path doesn't error out if a
directory is removed for it (thinking of odd races, here). Anyway, the
attached patch (diffed against current cvs) is more complete in this
respect. It gets rid of these rmdir_path calls.
-Jeff
Index: lib/cache.c
===================================================================
RCS file: /root/autofs/lib/cache.c,v
retrieving revision 1.14
diff -u -p -r1.14 cache.c
--- a/lib/cache.c 25 Apr 2005 03:42:08 -0000 1.14
+++ b/lib/cache.c 27 Apr 2005 00:22:41 -0000
@@ -312,18 +312,12 @@ void cache_clean(const char *root, time_
if (!path)
return;
- if (is_mounted(_PATH_MOUNTED, path)) {
- free(path);
- continue;
- }
-
if (me->age < age) {
pred->next = me->next;
free(me->key);
free(me->mapent);
free(me);
me = pred;
- rmdir_path(path);
}
free(path);
@@ -337,12 +331,8 @@ void cache_clean(const char *root, time_
if (!path)
return;
- if (is_mounted(_PATH_MOUNTED, path))
- continue;
-
if (me->age < age) {
mapent_hash[i] = me->next;
- rmdir_path(path);
free(me->key);
free(me->mapent);
free(me);
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