[PATCHv2 04/27] crypto: omap-sham: set sw fallback to 240 bytes
From: Tero Kristo <hidden>
Date: 2016-06-22 13:25:03
Also in:
linux-crypto, linux-omap
Subsystem:
crypto api, the rest · Maintainers:
Herbert Xu, "David S. Miller", Linus Torvalds
From: Bin Liu <b-liu@ti.com> Adds software fallback support for small crypto requests. In these cases, it is undesirable to use DMA, as setting it up itself is rather heavy operation. Gives about 40% extra performance in ipsec usecase. Signed-off-by: Bin Liu <b-liu@ti.com> [t-kristo at ti.com: dropped the extra traces, updated some comments on the code] Signed-off-by: Tero Kristo <redacted> --- drivers/crypto/omap-sham.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/drivers/crypto/omap-sham.c b/drivers/crypto/omap-sham.c
index fd3cac3..6247887 100644
--- a/drivers/crypto/omap-sham.c
+++ b/drivers/crypto/omap-sham.c@@ -1095,7 +1095,7 @@ static int omap_sham_update(struct ahash_request *req) ctx->offset = 0; if (ctx->flags & BIT(FLAGS_FINUP)) { - if ((ctx->digcnt + ctx->bufcnt + ctx->total) < 9) { + if ((ctx->digcnt + ctx->bufcnt + ctx->total) < 240) { /* * OMAP HW accel works only with buffers >= 9 * will switch to bypass in final()
@@ -1151,9 +1151,13 @@ static int omap_sham_final(struct ahash_request *req) if (ctx->flags & BIT(FLAGS_ERROR)) return 0; /* uncompleted hash is not needed */ - /* OMAP HW accel works only with buffers >= 9 */ - /* HMAC is always >= 9 because ipad == block size */ - if ((ctx->digcnt + ctx->bufcnt) < 9) + /* + * OMAP HW accel works only with buffers >= 9. + * HMAC is always >= 9 because ipad == block size. + * If buffersize is less than 240, we use fallback SW encoding, + * as using DMA + HW in this case doesn't provide any benefit. + */ + if ((ctx->digcnt + ctx->bufcnt) < 240) return omap_sham_final_shash(req); else if (ctx->bufcnt) return omap_sham_enqueue(req, OP_FINAL);
--
1.9.1