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SubjectRe: [PATCH] no need to check for NULL before calling kfree() -fs/ext2/
>Just looking at the third run, it seems to me that "if (likely(p))
>kfree(p);" beats a naked "kfree(p);" everytime, whether p is half
>NULL's, or very few NULL's, or almost all NULL's.

Well, kfree inlined was already mentioned but forgotten again.
What if this was used:

inline static void kfree_WRAP(void *addr) {
if(likely(addr != NULL)) {
kfree_real(addr);
}
return;
}

And remove the NULL-test in kfree_real()? Then we would have:

test eax, eax
jz afterwards;
<some more stuff for call>
call kfree_real;
.afterwards:
<continue execution>

The two cases then:
ptr==NULL: test-jmp
ptr!=NULL: test-call(freeit-return)

Looks like the least expensive way to me.


Jan Engelhardt
--
No TOFU for me, please.
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