From 58afa58a000dcb2040e65395e33e886814269e06 Mon Sep 17 00:00:00 2001
From: Ben Walker <benjamin.walker@intel.com>
Date: Tue, 9 May 2017 14:32:49 -0700
Subject: [PATCH] bdev: Simplify spdk_bdev_get_io_buf

This was implemented as two functions, but it
is much simpler as one. Also, the public function
was way at the bottom of the file instead of near
spdk_bdev_put_io_buf.

Change-Id: I3a90688910b0542cc77b6333bab15132cf514eeb
Signed-off-by: Ben Walker <benjamin.walker@intel.com>
---
 lib/bdev/bdev.c | 76 +++++++++++++++++++++++--------------------------
 1 file changed, 36 insertions(+), 40 deletions(-)

diff --git a/lib/bdev/bdev.c b/lib/bdev/bdev.c
index ad1da4271..47ac4bcaf 100644
--- a/lib/bdev/bdev.c
+++ b/lib/bdev/bdev.c
@@ -40,6 +40,7 @@
 #include <rte_lcore.h>
 #include "spdk/env.h"
 #include "spdk/io_channel.h"
+#include "spdk/likely.h"
 #include "spdk/queue.h"
 #include "spdk/nvme_spec.h"
 #include "spdk/scsi_spec.h"
@@ -167,6 +168,41 @@ spdk_bdev_io_put_buf(struct spdk_bdev_io *bdev_io)
 	}
 }
 
+void
+spdk_bdev_io_get_buf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_buf_cb cb)
+{
+	uint64_t len = bdev_io->u.read.len;
+	struct spdk_mempool *pool;
+	need_buf_tailq_t *tailq;
+	void *buf = NULL;
+
+	assert(cb != NULL);
+	assert(bdev_io->u.read.iovs != NULL);
+
+	if (spdk_unlikely(bdev_io->u.read.iovs[0].iov_base != NULL)) {
+		/* Buffer already present */
+		cb(bdev_io->ch->channel, bdev_io);
+		return;
+	}
+
+	bdev_io->get_buf_cb = cb;
+	if (len <= SPDK_BDEV_SMALL_BUF_MAX_SIZE) {
+		pool = g_bdev_mgr.buf_small_pool;
+		tailq = &g_bdev_mgr.need_buf_small[rte_lcore_id()];
+	} else {
+		pool = g_bdev_mgr.buf_large_pool;
+		tailq = &g_bdev_mgr.need_buf_large[rte_lcore_id()];
+	}
+
+	buf = spdk_mempool_get(pool);
+
+	if (!buf) {
+		TAILQ_INSERT_TAIL(tailq, bdev_io, buf_link);
+	} else {
+		spdk_bdev_io_set_buf(bdev_io, buf);
+	}
+}
+
 static int
 spdk_bdev_module_get_max_ctx_size(void)
 {
@@ -346,32 +382,6 @@ spdk_bdev_put_io(struct spdk_bdev_io *bdev_io)
 	spdk_mempool_put(g_bdev_mgr.bdev_io_pool, (void *)bdev_io);
 }
 
-static void
-_spdk_bdev_io_get_buf(struct spdk_bdev_io *bdev_io)
-{
-	uint64_t len = bdev_io->u.read.len;
-	struct spdk_mempool *pool;
-	need_buf_tailq_t *tailq;
-	void *buf = NULL;
-
-	if (len <= SPDK_BDEV_SMALL_BUF_MAX_SIZE) {
-		pool = g_bdev_mgr.buf_small_pool;
-		tailq = &g_bdev_mgr.need_buf_small[rte_lcore_id()];
-	} else {
-		pool = g_bdev_mgr.buf_large_pool;
-		tailq = &g_bdev_mgr.need_buf_large[rte_lcore_id()];
-	}
-
-	buf = spdk_mempool_get(pool);
-
-	if (!buf) {
-		TAILQ_INSERT_TAIL(tailq, bdev_io, buf_link);
-	} else {
-		spdk_bdev_io_set_buf(bdev_io, buf);
-	}
-}
-
-
 static void
 spdk_bdev_cleanup_pending_buf_io(struct spdk_bdev *bdev)
 {
@@ -1076,20 +1086,6 @@ spdk_bdev_unclaim(struct spdk_bdev *bdev)
 	}
 }
 
-void
-spdk_bdev_io_get_buf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_buf_cb cb)
-{
-	assert(cb != NULL);
-	assert(bdev_io->u.read.iovs != NULL);
-
-	if (bdev_io->u.read.iovs[0].iov_base == NULL) {
-		bdev_io->get_buf_cb = cb;
-		_spdk_bdev_io_get_buf(bdev_io);
-	} else {
-		cb(bdev_io->ch->channel, bdev_io);
-	}
-}
-
 void
 spdk_bdev_io_get_iovec(struct spdk_bdev_io *bdev_io, struct iovec **iovp, int *iovcntp)
 {