Re: [PATCH v10 2/2] Refactor part of the oom report in dump_header

[Andrew Morton]

On Sat, 23 Jun 2018 22:12:51 +0800 ufo19890607@xxxxxxxxx wrote:

> From: yuzhoujian <yuzhoujian@xxxxxxxxxxxxxxx>
> 
> The current system wide oom report prints information about the victim
> and the allocation context and restrictions. It, however, doesn't
> provide any information about memory cgroup the victim belongs to. This
> information can be interesting for container users because they can find
> the victim's container much more easily.
> 
> I follow the advices of David Rientjes and Michal Hocko, and refactor
> part of the oom report. After this patch, users can get the memcg's
> path from the oom report and check the certain container more quickly.
> 
> The oom print info after this patch:
> oom-kill:constraint=<constraint>,nodemask=<nodemask>,oom_memcg=<memcg>,task_memcg=<memcg>,task=<commm>,pid=<pid>,uid=<uid>
> 
> Signed-off-by: yuzhoujian <yuzhoujian@xxxxxxxxxxxxxxx>
> ---
> Below is the part of the oom report in the dmesg
> ...
> [  134.873392] panic invoked oom-killer: gfp_mask=0x6280ca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO), nodemask=(null), order=0, oom_score_adj=0
>
> ...
>
> [  134.873480] oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),task_memcg=/test/test1/test2,task=panic,pid= 8669,  uid=    0

We're displaying nodemask twice there.  Avoidable?

Also, the spaces after pid= and uid= don't seem useful.  Why not use
plain old %d?