Re: [PATCH] f2fs: add unlikely() macro for compiler more aggressively

[Andi Kleen]

Jaegeuk Kim <jaegeuk.kim@xxxxxxxxxxx> writes:
>  	struct page *page;
>  repeat:
>  	page = grab_cache_page(mapping, index);
> -	if (!page) {
> +	if (unlikely(!page)) {

This is completely pointless, gcc already considers any test for NULL
unlikely.

In general i would advise against splattering unlikely all over your
code, the benefits are very minimal and programers often get it wrong.

-Andi

-- 
ak@xxxxxxxxxxxxxxx -- Speaking for myself only
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