[PATCH] tcm_loop: Drop legacy host_lock usage in SHT->queuecommand() caller

From: Nicholas A. Bellinger
Date: Thu Nov 11 2010 - 05:25:33 EST


From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>

Following the the great host lock push-down in 3039f3ffcc5, this patch drops
the historical optimization (and most certain deadlock) of:

spin_unlock_irq(host_lock); do_some_lld_work(); spin_lock_irq(host_lock)

from within tcm_loop_queuecommand()

Signed-off-by: Nicholas A. Bellinger <nab@xxxxxxxxxxxxxxx>
---
drivers/target/tcm_loop/tcm_loop_fabric_scsi.c | 8 --------
1 files changed, 0 insertions(+), 8 deletions(-)

diff --git a/drivers/target/tcm_loop/tcm_loop_fabric_scsi.c b/drivers/target/tcm_loop/tcm_loop_fabric_scsi.c
index 80f2940..8175681 100644
--- a/drivers/target/tcm_loop/tcm_loop_fabric_scsi.c
+++ b/drivers/target/tcm_loop/tcm_loop_fabric_scsi.c
@@ -311,7 +311,6 @@ static int tcm_loop_queuecommand(
{
struct se_cmd *se_cmd;
struct se_portal_group *se_tpg;
- struct Scsi_Host *host = sc->device->host;
struct tcm_loop_hba *tl_hba;
struct tcm_loop_tpg *tl_tpg;

@@ -321,8 +320,6 @@ static int tcm_loop_queuecommand(
" scsi_buf_len: %u\n", sc->device->host->host_no,
sc->device->id, sc->device->channel, sc->device->lun,
sc->cmnd[0], scsi_bufflen(sc));
-
- spin_unlock_irq(host->host_lock);
/*
* Locate the tcm_loop_hba_t pointer
*/
@@ -342,7 +339,6 @@ static int tcm_loop_queuecommand(
*/
se_cmd = tcm_loop_allocate_core_cmd(tl_hba, se_tpg, sc);
if (!(se_cmd)) {
- spin_lock_irq(host->host_lock);
sc->result = host_byte(DID_ERROR);
(*done)(sc);
return 0;
@@ -351,10 +347,6 @@ static int tcm_loop_queuecommand(
* Queue up the newly allocated to be processed in TCM thread context.
*/
transport_generic_handle_cdb_map(se_cmd);
- /*
- * Reaquire the the struct scsi_host->host_lock before returning
- */
- spin_lock_irq(host->host_lock);
return 0;
}

--
1.5.6.5

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