[PATCH 11/12] megaraid_sas: Convert instance->issuepend_done to atomic_t

Nicholas A. Bellinger
2010-12-19T21:29:28Z

From: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts struct megasas_instance->issuepend_done to
an atomic_t fw_issuepend_done. This is because ->issuepend_done is
being used as a check to determine if SCSI_MLQUEUE_HOST_BUSY should
be returned during megasas_queue_command_lck(). So in order for a
conversion to lock-less operation to occur, this bit needs to be
handled in an atomic manner.

Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
---
drivers/scsi/megaraid/megaraid_sas.c | 13 ++++++-------
drivers/scsi/megaraid/megaraid_sas.h | 2 +-
2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c
index 31c5419..da0d3e3 100644
--- a/drivers/scsi/megaraid/megaraid_sas.c
+++ b/drivers/scsi/megaraid/megaraid_sas.c
@@ -1344,7 +1344,7 @@ megasas_queue_command_lck(struct scsi_cmnd *scmd, void (*done) (struct scsi_cmnd
instance = (struct megasas_instance *)
scmd->device->host->hostdata;

- if (instance->issuepend_done == 0)
+ if (atomic_read(&instance->fw_issuepend_done) == 0)
return SCSI_MLQUEUE_HOST_BUSY;

spin_lock_irqsave(&instance->hba_lock, flags);
@@ -1590,8 +1590,7 @@ void megasas_do_ocr(struct megasas_instance *instance)
}
instance->instancet->disable_intr(instance->reg_set);
instance->adprecovery = MEGASAS_ADPRESET_SM_INFAULT;
- instance->issuepend_done = 0;
-
+ atomic_set(&instance->fw_issuepend_done, 0);
atomic_set(&instance->fw_outstanding, 0);
megasas_internal_reset_defer_cmds(instance);
process_fw_state_change_wq(&instance->work_init);
@@ -1941,7 +1940,7 @@ megasas_service_aen(struct megasas_instance *instance, struct megasas_cmd *cmd)
megasas_return_cmd(instance, cmd);

if ((instance->unload == 0) &&
- ((instance->issuepend_done == 1))) {
+ ((atomic_read(&instance->fw_issuepend_done) == 1))) {
struct megasas_aen_event *ev;
ev = kzalloc(sizeof(*ev), GFP_ATOMIC);
if (!ev) {
@@ -2357,7 +2356,7 @@ process_fw_state_change_wq(struct work_struct *work)
instance->instancet->enable_intr(instance->reg_set);

megasas_issue_pending_cmds_again(instance);
- instance->issuepend_done = 1;
+ atomic_set(&instance->fw_issuepend_done, 1);
}
return ;
}
@@ -2417,8 +2416,8 @@ megasas_deplete_reply_queue(struct megasas_instance *instance,

instance->instancet->disable_intr(instance->reg_set);
instance->adprecovery = MEGASAS_ADPRESET_SM_INFAULT;
- instance->issuepend_done = 0;

+ atomic_set(&instance->fw_issuepend_done, 0);
atomic_set(&instance->fw_outstanding, 0);
megasas_internal_reset_defer_cmds(instance);

@@ -3798,7 +3797,7 @@ megasas_probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
megasas_poll_wait_aen = 0;
instance->flag_ieee = 0;
instance->ev = NULL;
- instance->issuepend_done = 1;
+ atomic_set(&instance->fw_issuepend_done, 1);
instance->adprecovery = MEGASAS_HBA_OPERATIONAL;
megasas_poll_wait_aen = 0;

diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h
index ad16f5e..eaeb873 100644
--- a/drivers/scsi/megaraid/megaraid_sas.h
+++ b/drivers/scsi/megaraid/megaraid_sas.h
@@ -1303,6 +1303,7 @@ struct megasas_instance {

atomic_t fw_outstanding;
atomic_t fw_reset_no_pci_access;
+ atomic_t fw_issuepend_done;

struct megasas_instance_template *instancet;
struct tasklet_struct isr_tasklet;
@@ -1311,7 +1312,6 @@ struct megasas_instance {
u8 flag;
u8 unload;
u8 flag_ieee;
- u8 issuepend_done;
u8 disableOnlineCtrlReset;
u8 adprecovery;
unsigned long last_time;
--
1.7.3.4