Messages in this thread |  | | Date | Sat, 24 Nov 2001 01:51:49 -0500 (EST) | From | Alexander Viro <> | Subject | Re: 2.4.15-pre9 breakage (inode.c) |
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On Sat, 24 Nov 2001, Andrea Arcangeli wrote:
> I don't care who has to do it, but who has to do it it has to do it in a > very very very very slow path, and you want to handle it in iput fast > path instead, cute?
Let's count. In the place where before -pre9 iput() had return; we have (2.4.15 + patch) if (!sb || sb->s_flags & MS_ACTIVE) return; and on the fast path the first is false and second is true.
Price: compare with zero not taken branch test (register + offset), <bit> not taken branch return instead of return Compare with the stuff we had done just before that. Pollution of fast path sucks, but here it _is_ noise.
I agree that variant in 2.4.15 is crap - hell, it's completely broken. Please, grab the patch in question, apply to 2.4.15 and look at the resulting code.
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