Re: [Ocfs2-devel] [PATCH] A bug in the end of DLM recovery

2016-08-07 Thread Eric Ren
Hi,

On 08/06/2016 01:58 PM, Gechangwei wrote:
> Hi,
>
> I found an issue in the end of DLM recovery.

What's the detailed steps of reproduction?

> When DLM recovery comes to the end of recovery procedure, it will remaster 
> all locks in other nodes.
> Right after a request message is sent to a node A (say), the new master node 
> will wait for node A’s response forever.
> But node A may die just after receiving the remaster request, not responses 
> to new master node yet.
> That causes new master node waiting forever.
> I think below patch can solve this problem. Please have a review!

Sorry, I cannot understand your problem. Could you give a more specific 
description
in the style such as this patch from Piaojun couple days ago:

ocfs2/dlm: disable BUG_ON when DLM_LOCK_RES_DROPPING_REF is cleared before 
dlm_deref_lockres_done_handler

Also, a patch should be for a real bug which can be produced, and a test for 
this patch must 
also be performed. I'm a little worried because this patch is seemingly based 
on assumption.


BTW, the format of your patche isn't formal;-) Please
go through docs below:

[1] 
https://github.com/torvalds/linux/blob/master/Documentation/SubmittingPatches
[2] https://github.com/torvalds/linux/blob/master/Documentation/SubmitChecklist

Eric

>
>
> Subject: [PATCH] interrupt waiting for node's response if node dies
>
> Signed-off-by: gechangwei 
> ---
> dlm/dlmrecovery.c | 4 
> 1 file changed, 4 insertions(+)
>
> diff --git a/dlm/dlmrecovery.c b/dlm/dlmrecovery.c
> index 3d90ad7..5e455cb 100644
> --- a/dlm/dlmrecovery.c
> +++ b/dlm/dlmrecovery.c
> @@ -679,6 +679,10 @@ static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 
> dead_node)
>  dlm->name, ndata->node_num,
>  
> ndata->state==DLM_RECO_NODE_DATA_RECEIVING ?
>  "receiving" : "requested");
> +if (dlm_is_node_dead(dlm, 
> ndata->node_num)) {
> +  mlog(0, "%s: node %u 
> died after requesting all locks.\n");
> +  ndata->state = 
> DLM_RECO_NODE_DATA_DONE;
> +}
> all_nodes_done = 0;
> break;
>case DLM_RECO_NODE_DATA_DONE:
> --
>
> BR.
>
> Chauncey
>
>
> -
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[Ocfs2-devel] [PATCH] A bug in the end of DLM recovery

2016-08-05 Thread Gechangwei
Hi,

I found an issue in the end of DLM recovery.
When DLM recovery comes to the end of recovery procedure, it will remaster all 
locks in other nodes.
Right after a request message is sent to a node A (say), the new master node 
will wait for node A’s response forever.
But node A may die just after receiving the remaster request, not responses to 
new master node yet.
That causes new master node waiting forever.
I think below patch can solve this problem. Please have a review!


Subject: [PATCH] interrupt waiting for node's response if node dies

Signed-off-by: gechangwei 
---
dlm/dlmrecovery.c | 4 
1 file changed, 4 insertions(+)

diff --git a/dlm/dlmrecovery.c b/dlm/dlmrecovery.c
index 3d90ad7..5e455cb 100644
--- a/dlm/dlmrecovery.c
+++ b/dlm/dlmrecovery.c
@@ -679,6 +679,10 @@ static int dlm_remaster_locks(struct dlm_ctxt *dlm, u8 
dead_node)
 dlm->name, ndata->node_num,
 
ndata->state==DLM_RECO_NODE_DATA_RECEIVING ?
 "receiving" : "requested");
+if (dlm_is_node_dead(dlm, 
ndata->node_num)) {
+  mlog(0, "%s: node %u 
died after requesting all locks.\n");
+  ndata->state = 
DLM_RECO_NODE_DATA_DONE;
+}
all_nodes_done = 0;
break;
   case DLM_RECO_NODE_DATA_DONE:
--

BR.

Chauncey


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的个人或群组。禁止任何其他人以任何形式使用(包括但不限于全部或部分地泄露、复制、
或散发)本邮件中的信息。如果您错收了本邮件,请您立即电话或邮件通知发件人并删除本
邮件!
This e-mail and its attachments contain confidential information from H3C, 
which is
intended only for the person or entity whose address is listed above. Any use 
of the
information contained herein in any way (including, but not limited to, total 
or partial
disclosure, reproduction, or dissemination) by persons other than the intended
recipient(s) is prohibited. If you receive this e-mail in error, please notify 
the sender
by phone or email immediately and delete it!
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