9b83ecb0a3
The main loop of csum_partial runs very slowly on recent POWER CPUs. After some analysis on both POWER6 and POWER7 I came up with routine below. First we get the source aligned to a double word, ignoring any odd alignment to keep things simple. Then we do 64 bytes at a time, with an entry and exit limb of a further 64 bytes. On both POWER6 and POWER7 this should be as fast as we can go since we are limited by the latency of the adde instructions. To test this I forced checksumming on over loopback and ran socklib (a simple TCP benchmark). On a POWER6 575 throughput improved by 11% with this patch. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> |
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| boot | ||
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| lib | ||
| math-emu | ||
| mm | ||
| oprofile | ||
| platforms | ||
| sysdev | ||
| xmon | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||
| relocs_check.pl | ||