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target: Remove legacy t_fe_count + avoid t_state_lock access in transport_put_cmd

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This patch removes legacy se_cmd->t_fe_count usage in order to avoid
se_cmd->t_state_lock access within transport_put_cmd() during normal
fast path se_cmd descriptor release.

Also drop the left-over parameter usage within core_tmr_handle_tas_abort()

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>
This commit is contained in:
Nicholas Bellinger 2013-06-06 02:00:06 -07:00
parent 0b66818ac6
commit c1c35d5225
3 changed files with 2 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
drivers/target/target_core_tmr.c
View File

@ -85,13 +85,8 @@ void core_tmr_release_req(
static void core_tmr_handle_tas_abort(
struct se_node_acl *tmr_nacl,
struct se_cmd *cmd,
int tas,
int fe_count)
int tas)
{
if (!fe_count) {
transport_cmd_finish_abort(cmd, 1);
return;
}
/*
* TASK ABORTED status (TAS) bit support
*/
@ -253,7 +248,6 @@ static void core_tmr_drain_state_list(
LIST_HEAD(drain_task_list);
struct se_cmd *cmd, *next;
unsigned long flags;
int fe_count;
/*
* Complete outstanding commands with TASK_ABORTED SAM status.
@ -329,12 +323,10 @@ static void core_tmr_drain_state_list(
spin_lock_irqsave(&cmd->t_state_lock, flags);
target_stop_cmd(cmd, &flags);
fe_count = atomic_read(&cmd->t_fe_count);
cmd->transport_state |= CMD_T_ABORTED;
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
core_tmr_handle_tas_abort(tmr_nacl, cmd, tas, fe_count);
core_tmr_handle_tas_abort(tmr_nacl, cmd, tas);
}
}

18
drivers/target/target_core_transport.c
View File

@ -1968,21 +1968,6 @@ static int transport_release_cmd(struct se_cmd *cmd)
*/
static int transport_put_cmd(struct se_cmd *cmd)
{
unsigned long flags;
spin_lock_irqsave(&cmd->t_state_lock, flags);
if (atomic_read(&cmd->t_fe_count) &&
!atomic_dec_and_test(&cmd->t_fe_count)) {
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
return 0;
}
if (cmd->transport_state & CMD_T_DEV_ACTIVE) {
cmd->transport_state &= ~CMD_T_DEV_ACTIVE;
target_remove_from_state_list(cmd);
}
spin_unlock_irqrestore(&cmd->t_state_lock, flags);
transport_free_pages(cmd);
return transport_release_cmd(cmd);
}
@ -2100,9 +2085,6 @@ transport_generic_new_cmd(struct se_cmd *cmd)
if (ret < 0)
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}
atomic_inc(&cmd->t_fe_count);
/*
* If this command is not a write we can execute it right here,
* for write buffers we need to notify the fabric driver first

1
include/target/target_core_base.h
View File

@ -454,7 +454,6 @@ struct se_cmd {
unsigned char *t_task_cdb;
unsigned char __t_task_cdb[TCM_MAX_COMMAND_SIZE];
unsigned long long t_task_lba;
atomic_t t_fe_count;
unsigned int transport_state;
#define CMD_T_ABORTED (1 << 0)
#define CMD_T_ACTIVE (1 << 1)