Re: [PATCH] mm: be more informative in OOM task list

From: David Rientjes
Date: Tue Jul 03 2018 - 21:34:55 EST


On Sun, 1 Jul 2018, Rodrigo Freire wrote:

> The default page memory unit of OOM task dump events might not be
> intuitive for the non-initiated when debugging OOM events. Add
> a small printk prior to the task dump informing that the memory
> units are actually memory _pages_.
>
> Signed-off-by: Rodrigo Freire <rfreire@xxxxxxxxxx>
> ---
> mm/oom_kill.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/mm/oom_kill.c b/mm/oom_kill.c
> index 84081e7..b4d9557 100644
> --- a/mm/oom_kill.c
> +++ b/mm/oom_kill.c
> @@ -392,6 +392,7 @@ static void dump_tasks(struct mem_cgroup *memcg, const nodemask_t *nodemask)
> struct task_struct *p;
> struct task_struct *task;
>
> + pr_info("Tasks state (memory values in pages):\n");
> pr_info("[ pid ] uid tgid total_vm rss pgtables_bytes swapents oom_score_adj name\n");
> rcu_read_lock();
> for_each_process(p) {

As the author of dump_tasks(), and having seen these values misinterpreted
on more than one occassion, I think this is a valuable addition.

Could you also expand out the "pid" field to allow for seven digits
instead of five? I think everything else is aligned.

Feel free to add

Acked-by: David Rientjes <rientjes@xxxxxxxxxx>

to a v2.