[Ocfs2-devel] [PATCH] ocfs2: Optimization of code while free dead locks.

[Eric Ren]

Hi,

On 11/26/2016 08:15 PM, Guozhonghua wrote:
> The three loops can be optimized into one loop and its sub loops, so as small code can do the same work.
> The patch is based on the linux-4.9-rc6.
>
> Signed-off-by: Guozhonghua <guozhonghua at h3c.com>
>
>
> --- ocfs2.orig/dlm/dlmrecovery.c        2016-11-26 19:13:04.833023242 +0800
> +++ ocfs2/dlm/dlmrecovery.c     2016-11-26 19:24:03.982552497 +0800
I don't think this patch could be applied cleanly:
------
zhen at desktop:~/linux> git am ~/patches/temp/\[PATCH\]\ ocfs2\:\ Optimization\ of\ code\ 
while\ free\ dead\ locks..eml
Applying: ocfs2: Optimization of code while free dead locks.
.git/rebase-apply/patch:7: trailing whitespace.
        struct list_head *queue = NULL;
.git/rebase-apply/patch:8: trailing whitespace.
        int i;
fatal: corrupt patch at line 9
Patch failed at 0001 ocfs2: Optimization of code while free dead locks.
------

Please go through the docs below:
[1] https://kernelnewbies.org/FirstKernelPatch

The file path (ocfs2/dlm/dlmrecovery.c ) is weird.  It should be like:

                   diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c

> @@ -2268,6 +2268,8 @@ static void dlm_free_dead_locks(struct d
>   {
>          struct dlm_lock *lock, *next;
>          unsigned int freed = 0;
> +       struct list_head *queue = NULL;
> +       int i;
>
>          /* this node is the lockres master:
>           * 1) remove any stale locks for the dead node
> @@ -2280,33 +2282,19 @@ static void dlm_free_dead_locks(struct d
>           * to force the DLM_UNLOCK_FREE_LOCK action so as to free the locks */
>
>          /* TODO: check pending_asts, pending_basts here */
> -       list_for_each_entry_safe(lock, next, &res->granted, list) {
> -               if (lock->ml.node == dead_node) {
> -                       list_del_init(&lock->list);
> -                       dlm_lock_put(lock);
> -                       /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
> -                       dlm_lock_put(lock);
> -                       freed++;
> +       for (i = DLM_BLOCKED_LIST; i >= DLM_GRANTED_LIST; i--) {

Is it right to loop the lists in a reversed order to the original?

Eric
> +               queue = dlm_list_idx_to_ptr(res, i);
> +               list_for_each_entry_safe(lock, next, queue, list) {
> +                       if (lock->ml.node == dead_node) {
> +                               list_del_init(&lock->list);
> +                               dlm_lock_put(lock);
> +
> +                               /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
> +                               dlm_lock_put(lock);
> +                               freed++;
> +                       }
>                  }
> -       }
> -       list_for_each_entry_safe(lock, next, &res->converting, list) {
> -               if (lock->ml.node == dead_node) {
> -                       list_del_init(&lock->list);
> -                       dlm_lock_put(lock);
> -                       /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
> -                       dlm_lock_put(lock);
> -                       freed++;
> -               }
> -       }
> -       list_for_each_entry_safe(lock, next, &res->blocked, list) {
> -               if (lock->ml.node == dead_node) {
> -                       list_del_init(&lock->list);
> -                       dlm_lock_put(lock);
> -                       /* Can't schedule DLM_UNLOCK_FREE_LOCK - do manually */
> -                       dlm_lock_put(lock);
> -                       freed++;
> -               }
> -       }
> +       }
>
>          if (freed) {
>                  mlog(0, "%s:%.*s: freed %u locks for dead node %u, "
>
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