crypto: poly1305 - Add a two block SSE2 variant for x86_64
Extends the x86_64 SSE2 Poly1305 authenticator by a function processing two
consecutive Poly1305 blocks in parallel using a derived key r^2. Loop
unrolling can be more effectively mapped to SSE instructions, further
increasing throughput.
For large messages, throughput increases by ~45-65% compared to single
block SSE2:
testing speed of poly1305 (poly1305-simd)
test 0 ( 96 byte blocks, 16 bytes per update, 6 updates): 3790063 opers/sec, 363846076 bytes/sec
test 1 ( 96 byte blocks, 32 bytes per update, 3 updates): 5913378 opers/sec, 567684355 bytes/sec
test 2 ( 96 byte blocks, 96 bytes per update, 1 updates): 9352574 opers/sec, 897847104 bytes/sec
test 3 ( 288 byte blocks, 16 bytes per update, 18 updates): 1362145 opers/sec, 392297990 bytes/sec
test 4 ( 288 byte blocks, 32 bytes per update, 9 updates): 2007075 opers/sec, 578037628 bytes/sec
test 5 ( 288 byte blocks, 288 bytes per update, 1 updates): 3709811 opers/sec, 1068425798 bytes/sec
test 6 ( 1056 byte blocks, 32 bytes per update, 33 updates): 566272 opers/sec, 597984182 bytes/sec
test 7 ( 1056 byte blocks, 1056 bytes per update, 1 updates): 1111657 opers/sec, 1173910108 bytes/sec
test 8 ( 2080 byte blocks, 32 bytes per update, 65 updates): 288857 opers/sec, 600823808 bytes/sec
test 9 ( 2080 byte blocks, 2080 bytes per update, 1 updates): 590746 opers/sec, 1228751888 bytes/sec
test 10 ( 4128 byte blocks, 4128 bytes per update, 1 updates): 301825 opers/sec, 1245936902 bytes/sec
test 11 ( 8224 byte blocks, 8224 bytes per update, 1 updates): 153075 opers/sec, 1258896201 bytes/sec
testing speed of poly1305 (poly1305-simd)
test 0 ( 96 byte blocks, 16 bytes per update, 6 updates): 3809514 opers/sec, 365713411 bytes/sec
test 1 ( 96 byte blocks, 32 bytes per update, 3 updates): 5973423 opers/sec, 573448627 bytes/sec
test 2 ( 96 byte blocks, 96 bytes per update, 1 updates): 9446779 opers/sec, 906890803 bytes/sec
test 3 ( 288 byte blocks, 16 bytes per update, 18 updates): 1364814 opers/sec, 393066691 bytes/sec
test 4 ( 288 byte blocks, 32 bytes per update, 9 updates): 2045780 opers/sec, 589184697 bytes/sec
test 5 ( 288 byte blocks, 288 bytes per update, 1 updates): 3711946 opers/sec, 1069040592 bytes/sec
test 6 ( 1056 byte blocks, 32 bytes per update, 33 updates): 573686 opers/sec, 605812732 bytes/sec
test 7 ( 1056 byte blocks, 1056 bytes per update, 1 updates): 1647802 opers/sec, 1740079440 bytes/sec
test 8 ( 2080 byte blocks, 32 bytes per update, 65 updates): 292970 opers/sec, 609378224 bytes/sec
test 9 ( 2080 byte blocks, 2080 bytes per update, 1 updates): 943229 opers/sec, 1961916528 bytes/sec
test 10 ( 4128 byte blocks, 4128 bytes per update, 1 updates): 494623 opers/sec, 2041804569 bytes/sec
test 11 ( 8224 byte blocks, 8224 bytes per update, 1 updates): 254045 opers/sec, 2089271014 bytes/sec
Benchmark results from a Core i5-4670T.
Signed-off-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/arch/x86/crypto/poly1305_glue.c b/arch/x86/crypto/poly1305_glue.c
index 1e59274..b7c33d0 100644
--- a/arch/x86/crypto/poly1305_glue.c
+++ b/arch/x86/crypto/poly1305_glue.c
@@ -18,24 +18,68 @@
#include <asm/fpu/api.h>
#include <asm/simd.h>
+struct poly1305_simd_desc_ctx {
+ struct poly1305_desc_ctx base;
+ /* derived key u set? */
+ bool uset;
+ /* derived Poly1305 key r^2 */
+ u32 u[5];
+};
+
asmlinkage void poly1305_block_sse2(u32 *h, const u8 *src,
const u32 *r, unsigned int blocks);
+asmlinkage void poly1305_2block_sse2(u32 *h, const u8 *src, const u32 *r,
+ unsigned int blocks, const u32 *u);
+
+static int poly1305_simd_init(struct shash_desc *desc)
+{
+ struct poly1305_simd_desc_ctx *sctx = shash_desc_ctx(desc);
+
+ sctx->uset = false;
+
+ return crypto_poly1305_init(desc);
+}
+
+static void poly1305_simd_mult(u32 *a, const u32 *b)
+{
+ u8 m[POLY1305_BLOCK_SIZE];
+
+ memset(m, 0, sizeof(m));
+ /* The poly1305 block function adds a hi-bit to the accumulator which
+ * we don't need for key multiplication; compensate for it. */
+ a[4] -= 1 << 24;
+ poly1305_block_sse2(a, m, b, 1);
+}
static unsigned int poly1305_simd_blocks(struct poly1305_desc_ctx *dctx,
const u8 *src, unsigned int srclen)
{
+ struct poly1305_simd_desc_ctx *sctx;
unsigned int blocks, datalen;
+ BUILD_BUG_ON(offsetof(struct poly1305_simd_desc_ctx, base));
+ sctx = container_of(dctx, struct poly1305_simd_desc_ctx, base);
+
if (unlikely(!dctx->sset)) {
datalen = crypto_poly1305_setdesckey(dctx, src, srclen);
src += srclen - datalen;
srclen = datalen;
}
+ if (likely(srclen >= POLY1305_BLOCK_SIZE * 2)) {
+ if (unlikely(!sctx->uset)) {
+ memcpy(sctx->u, dctx->r, sizeof(sctx->u));
+ poly1305_simd_mult(sctx->u, dctx->r);
+ sctx->uset = true;
+ }
+ blocks = srclen / (POLY1305_BLOCK_SIZE * 2);
+ poly1305_2block_sse2(dctx->h, src, dctx->r, blocks, sctx->u);
+ src += POLY1305_BLOCK_SIZE * 2 * blocks;
+ srclen -= POLY1305_BLOCK_SIZE * 2 * blocks;
+ }
if (srclen >= POLY1305_BLOCK_SIZE) {
- blocks = srclen / POLY1305_BLOCK_SIZE;
- poly1305_block_sse2(dctx->h, src, dctx->r, blocks);
- srclen -= POLY1305_BLOCK_SIZE * blocks;
+ poly1305_block_sse2(dctx->h, src, dctx->r, 1);
+ srclen -= POLY1305_BLOCK_SIZE;
}
return srclen;
}
@@ -84,11 +128,11 @@
static struct shash_alg alg = {
.digestsize = POLY1305_DIGEST_SIZE,
- .init = crypto_poly1305_init,
+ .init = poly1305_simd_init,
.update = poly1305_simd_update,
.final = crypto_poly1305_final,
.setkey = crypto_poly1305_setkey,
- .descsize = sizeof(struct poly1305_desc_ctx),
+ .descsize = sizeof(struct poly1305_simd_desc_ctx),
.base = {
.cra_name = "poly1305",
.cra_driver_name = "poly1305-simd",