From ae77cbc1e7b90473a2b0963bce0e1eb163873214 Mon Sep 17 00:00:00 2001 From: Ken Steele Date: Wed, 7 Aug 2013 12:39:56 -0400 Subject: RAID: add tilegx SIMD implementation of raid6 This change adds TILE-Gx SIMD instructions to the software raid (md), modeling the Altivec implementation. This is only for Syndrome generation; there is more that could be done to improve recovery, as in the recent Intel SSE3 recovery implementation. The code unrolls 8 times; this turns out to be the best on tilegx hardware among the set 1, 2, 4, 8 or 16. The code reads one cache-line of data from each disk, stores P and Q then goes to the next cache-line. The test code in sys/linux/lib/raid6/test reports 2008 MB/s data read rate for syndrome generation using 18 disks (16 data and 2 parity). It was 1512 MB/s before this SIMD optimizations. This is running on 1 core with all the data in cache. This is based on the paper The Mathematics of RAID-6. (http://kernel.org/pub/linux/kernel/people/hpa/raid6.pdf). Signed-off-by: Ken Steele Signed-off-by: Chris Metcalf Signed-off-by: NeilBrown --- include/linux/raid/pq.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/raid') diff --git a/include/linux/raid/pq.h b/include/linux/raid/pq.h index 8dfaa2ce2e95..6d5df8adb53a 100644 --- a/include/linux/raid/pq.h +++ b/include/linux/raid/pq.h @@ -101,6 +101,7 @@ extern const struct raid6_calls raid6_altivec8; extern const struct raid6_calls raid6_avx2x1; extern const struct raid6_calls raid6_avx2x2; extern const struct raid6_calls raid6_avx2x4; +extern const struct raid6_calls raid6_tilegx8; struct raid6_recov_calls { void (*data2)(int, size_t, int, int, void **); -- cgit v1.2.2