Re: [PATCH v2 9/9] mm, oom: print symbolic gfp_flags in oom warning

[Michal Hocko <mhocko@kernel.org>]

On Tue 24-11-15 13:36:21, Vlastimil Babka wrote:
> It would be useful to translate gfp_flags into string representation when
> printing in case of an OOM, especially as the flags have been undergoing some
> changes recently and the script ./scripts/gfp-translate needs a matching source
> version to be accurate.
> 
> Example output:
> 
> a.out invoked oom-killer: order=0, oom_score_adj=0, gfp_mask=0x24280ca(GFP_HIGHUSER_MOVABLE|GFP_ZERO)

I like this _very much_
 
> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

If this can be done with a printk formatter it would be even nicer but
this is good enough for the OOM purpose.

Acked-by: Michal Hocko <mhocko@suse.com>

> ---
>  mm/oom_kill.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/mm/oom_kill.c b/mm/oom_kill.c
> index 5314b20..542d56c 100644
> --- a/mm/oom_kill.c
> +++ b/mm/oom_kill.c
> @@ -386,10 +386,12 @@ static void dump_tasks(struct mem_cgroup *memcg, const nodemask_t *nodemask)
>  static void dump_header(struct oom_control *oc, struct task_struct *p,
>  			struct mem_cgroup *memcg)
>  {
> -	pr_warning("%s invoked oom-killer: gfp_mask=0x%x, order=%d, "
> -		"oom_score_adj=%hd\n",
> -		current->comm, oc->gfp_mask, oc->order,
> -		current->signal->oom_score_adj);
> +	pr_warning("%s invoked oom-killer: order=%d, oom_score_adj=%hd, "
> +			"gfp_mask=0x%x",
> +		current->comm, oc->order, current->signal->oom_score_adj,
> +		oc->gfp_mask);
> +	dump_gfpflag_names(oc->gfp_mask);
> +
>  	cpuset_print_current_mems_allowed();
>  	dump_stack();
>  	if (memcg)
> -- 
> 2.6.3

-- 
Michal Hocko
SUSE Labs