Messages in this thread | | | From | Andi Kleen <> | Subject | Re: [Patch 4/4] Tell GCC 4.1 to move unlikely() code to a separate section | Date | Mon, 27 Feb 2006 16:39:34 +0100 |
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On Monday 27 February 2006 16:31, Arjan van de Ven wrote: > This patch is more controversial I assume; it offers the option > to use the gcc 4.1 option to move unlikely() code to a separate section. > On the con side, this means that longer byte sequences are needed to jump > to this code, on the Pro side it means that the unlikely() code isn't sharing > icache cachelines and tlbs anymore.
I don't think this will do anything because the default Makefile still has
CFLAGS += -fno-reorder-blocks
That was me because it made assembly debugging much easier. I would be willing to reconsider this if you can give me some hard data just from this change: - benchmark changes - .text size increase
Also I don't like it being an separate CONFIG options. We already have too many obscure ones. Either it should be on by default or not there at all.
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