From: Nicholas Bellinger <nab@linux-iscsi.org>
Date: Thu, 6 Jun 2013 08:58:04 +0000 (-0700)
Subject: target: Drop unnecessary t_state_lock access for SCF_SUPPORTED_SAM_OPCODE assignment
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=b28e545c4ddd7b594c64e8f3d9c2891eda253afc;p=deliverable%2Flinux.git

target: Drop unnecessary t_state_lock access for SCF_SUPPORTED_SAM_OPCODE assignment

This patch drops the se_cmd->t_state_lock access around SCF_SUPPORTED_SAM_OPCODE
assignment within target_setup_cmd_from_cdb().

Original v4.0 target code required this as fabrics would be checking for
this values in different process contexts for setup and I/O submission.

Given that modern v4.1 target code performs setup and I/O submission
from the same process context, this t_state_lock access is no longer
required.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@kernel.org>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Moussa Ba <moussaba@micron.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
---

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index e9ba012e82a9..94c5b323db3c 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -1089,7 +1089,6 @@ sense_reason_t
 target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
 {
 	struct se_device *dev = cmd->se_dev;
-	unsigned long flags;
 	sense_reason_t ret;
 
 	/*
@@ -1149,9 +1148,7 @@ target_setup_cmd_from_cdb(struct se_cmd *cmd, unsigned char *cdb)
 	if (ret)
 		return ret;
 
-	spin_lock_irqsave(&cmd->t_state_lock, flags);
 	cmd->se_cmd_flags |= SCF_SUPPORTED_SAM_OPCODE;
-	spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
 	spin_lock(&cmd->se_lun->lun_sep_lock);
 	if (cmd->se_lun->lun_sep)