On Saturday January 12, [EMAIL PROTECTED] wrote:
> This is a combined patch that has:
>
> * changes made by Christoph Hellwig
> * code segment that handles f_locks so we would not walk inode->i_flock
> list twice.
>
> If agreed, please re-add your "ack-by" and "signed-off" lines
> respectively. Thanks ...
>
> - int i, ret = 0;
> + int i, ret = 0, inspect_file;
>
> mutex_lock(&nlm_file_mutex);
> for (i = 0; i < FILE_NRHASH; i++) {
> hlist_for_each_entry_safe(file, pos, next, &nlm_files[i],
> f_list) {
> file->f_count++;
> mutex_unlock(&nlm_file_mutex);
> + inspect_file = 1;
>
> /* Traverse locks, blocks and shares of this file
> * and update file->f_locks count */
> - if (nlm_inspect_file(host, file, match))
> +
> + if (unlikely(failover)) {
> + if (!failover(data, file)) {
> + inspect_file = 0;
> + file->f_locks = nlm_file_inuse(file);
> + }
> + }
> +
> + if (inspect_file && nlm_inspect_file(data, file, match))
> ret = 1;
if (unlikely(failover) &&
!failover(data, file))
file->f_locks = nlm_file_inuse(file);
else if (nlm_inspect_file(data, file, match))
ret = 1;
Though the logic still isn't very clear... maybe:
if (likely(failover == NULL) ||
failover(data, file))
ret |= nlm_inspect_file(data, file, match);
else
file->f_locks = nlm_file_inuse(file);
Actually I would like to make nlm_inspect_file return 'void'.
The returned value of '1' is ultimately either ignored or it triggers
a BUG(). And the case where it triggers a BUG is the "host != NULL"
case. (I think - if someone could check, that would be good).
So putting BUG_ON(host) in nlm_traverse_locks (along with a nice big
comment) would mean we can discard the return value from
nlm_traverse_locks and nlm_inspect_file and nlm_traverse_files.
Also, if we could change the function name 'failover' to some sort of
verb like "is_failover" or "is_failover_file", then the above could be
if (likely(is_failover_file == NULL) ||
is_failover_file(data, file))
/* note nlm_inspect_file updates f_locks */
nlm_inspect_file(data, file, match);
else
file->f_locks = nlm_file_inuse(file);
>
> mutex_lock(&nlm_file_mutex);
> file->f_count--;
> /* No more references to this file. Let go of it. */
> - if (list_empty(&file->f_blocks) && !file->f_locks
> + if (!file->f_locks && list_empty(&file->f_blocks)
Is this change actually achieving something? or is it just noise?
NeilBrown
