Re: [PATCH v2] mm/page_alloc: bail out on fatal signal during reclaim/compaction retry attempt

[Matthew Wilcox]

On Wed, May 19, 2021 at 08:23:21PM +0100, Aaron Tomlin wrote:
> +++ b/mm/page_alloc.c
> @@ -4252,6 +4252,9 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
>  	if (!order)
>  		return false;
>  
> +	if (fatal_signal_pending(current))
> +		goto out;

I think 'goto out' will be confusing.  It'll output a tracepoint, which
isn't going to record that a fatal signal is pending, so it'll cause
some head scratching for someone looking through the traces.  I
think we should just return false here and skip the tracepoint.

But I'd defer to someone like Vlastimil or Michal who know this code far
better than I do.