Use Multi-buffer sha256 support from SPL

If SPL is configured with multi-buffer hash, it will export a C predefine marco HAVE_HASH_MB and C api mulbuf_sha256 to ZFS. Using this api, performance of sha256 will be increased 2~7 times. Signed-off-by: Xiaodong Liu <[email protected]> Requires-spl: refs/pull/646/head
openzfs · Aug 23, 2017 · 8b83a54 · 8b83a54
1 parent db4c1ad
commit 8b83a54
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diff --git a/module/zfs/sha256.c b/module/zfs/sha256.c
@@ -31,6 +31,17 @@
 #include <sys/sha2.h>
 #include <sys/abd.h>
 
+
+#if defined(__x86_64) && defined(_KERNEL) && defined(HAVE_HASH_MB)
+
+extern int mulbuf_sha256(void *buffer, size_t size, unsigned char *digest);
+
+int zfs_hash_mb_disable = B_FALSE;
+module_param(zfs_hash_mb_disable, int, 0644);
+MODULE_PARM_DESC(zfs_hash_mb_disable, "Disable multi-buffer sha256");
+
+#endif
+
 static int
 sha_incremental(void *buf, size_t size, void *arg)
 {
@@ -47,6 +58,19 @@ abd_checksum_SHA256(abd_t *abd, uint64_t size,
 	SHA2_CTX ctx;
 	zio_cksum_t tmp;
 
+#if defined(__x86_64) && defined(_KERNEL) && defined(HAVE_HASH_MB)
+
+	void *buffer;
+
+	if (abd_is_linear(abd) && size > 8 * 1024 && !zfs_hash_mb_disable) {
+		buffer = abd->abd_u.abd_linear.abd_buf;
+		mulbuf_sha256(buffer, size, (unsigned char *)zcp);
+
+		return;
+	}
+
+#endif /* _KERNEL && __x86_64 && HAVE_HASH_MB */
+
 	SHA2Init(SHA256, &ctx);
 	(void) abd_iterate_func(abd, 0, size, sha_incremental, &ctx);
 	SHA2Final(&tmp, &ctx);

diff --git a/module/zfs/spa.c b/module/zfs/spa.c
@@ -161,6 +161,7 @@ static inline int spa_load_impl(spa_t *spa, uint64_t, nvlist_t *config,
     char **ereport);
 static void spa_vdev_resilver_done(spa_t *spa);
 
+extern int zfs_hash_mb_disable;
 uint_t		zio_taskq_batch_pct = 75;	/* 1 thread per cpu in pset */
 id_t		zio_taskq_psrset_bind = PS_NONE;
 boolean_t	zio_taskq_sysdc = B_TRUE;	/* use SDC scheduling class */
@@ -899,6 +900,13 @@ spa_taskqs_init(spa_t *spa, zio_type_t t, zio_taskq_type_t q)
 	case ZTI_MODE_BATCH:
 		batch = B_TRUE;
 		flags |= TASKQ_THREADS_CPU_PCT;
+
+#if defined(__x86_64) && defined(_KERNEL) && defined(HAVE_HASH_MB)
+		/* Eightfold threads cpu percentage */
+		if (!zfs_hash_mb_disable)
+			value = zio_taskq_batch_pct * 8;
+		else
+#endif
 		value = MIN(zio_taskq_batch_pct, 100);
 		break;