From e4a082c7c1f9a7b11fece6918e7ee5519b39ac46 Mon Sep 17 00:00:00 2001 From: Sumant Patro Date: Tue, 30 May 2006 12:03:37 -0700 Subject: [PATCH] [SCSI] megaraid_sas: switch fw_outstanding to an atomic_t This patch( originally submitted by Christoph Hellwig) removes instance_lock and changes fw_outstanding variable data type to atomic_t. Signed-off-by: Sumant Patro Signed-off-by: James Bottomley --- Documentation/scsi/ChangeLog.megaraid_sas | 13 ++++++++++++ drivers/scsi/megaraid/megaraid_sas.c | 26 +++++++++-------------- drivers/scsi/megaraid/megaraid_sas.h | 3 +-- 3 files changed, 24 insertions(+), 18 deletions(-) diff --git a/Documentation/scsi/ChangeLog.megaraid_sas b/Documentation/scsi/ChangeLog.megaraid_sas index 2dafa63bd3..0a85a7e812 100644 --- a/Documentation/scsi/ChangeLog.megaraid_sas +++ b/Documentation/scsi/ChangeLog.megaraid_sas @@ -1,3 +1,16 @@ + +1 Release Date : Wed Feb 03 14:31:44 PST 2006 - Sumant Patro +2 Current Version : 00.00.02.04 +3 Older Version : 00.00.02.04 + +i. Remove superflous instance_lock + + gets rid of the otherwise superflous instance_lock and avoids an unsave + unsynchronized access in the error handler. + + - Christoph Hellwig + + 1 Release Date : Wed Feb 03 14:31:44 PST 2006 - Sumant Patro 2 Current Version : 00.00.02.04 3 Older Version : 00.00.02.04 diff --git a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c index 39729460b0..0c9516ff63 100644 --- a/drivers/scsi/megaraid/megaraid_sas.c +++ b/drivers/scsi/megaraid/megaraid_sas.c @@ -741,7 +741,6 @@ static int megasas_queue_command(struct scsi_cmnd *scmd, void (*done) (struct scsi_cmnd *)) { u32 frame_count; - unsigned long flags; struct megasas_cmd *cmd; struct megasas_instance *instance; @@ -776,9 +775,7 @@ megasas_queue_command(struct scsi_cmnd *scmd, void (*done) (struct scsi_cmnd *)) /* * Issue the command to the FW */ - spin_lock_irqsave(&instance->instance_lock, flags); - instance->fw_outstanding++; - spin_unlock_irqrestore(&instance->instance_lock, flags); + atomic_inc(&instance->fw_outstanding); instance->instancet->fire_cmd(cmd->frame_phys_addr ,cmd->frame_count-1,instance->reg_set); @@ -826,19 +823,20 @@ static int megasas_wait_for_outstanding(struct megasas_instance *instance) for (i = 0; i < wait_time; i++) { - if (!instance->fw_outstanding) + int outstanding = atomic_read(&instance->fw_outstanding); + + if (!outstanding) break; if (!(i % MEGASAS_RESET_NOTICE_INTERVAL)) { printk(KERN_NOTICE "megasas: [%2d]waiting for %d " - "commands to complete\n", i, - instance->fw_outstanding); + "commands to complete\n",i,outstanding); } msleep(1000); } - if (instance->fw_outstanding) { + if (atomic_read(&instance->fw_outstanding)) { instance->hw_crit_error = 1; return FAILED; } @@ -1050,7 +1048,6 @@ megasas_complete_cmd(struct megasas_instance *instance, struct megasas_cmd *cmd, { int exception = 0; struct megasas_header *hdr = &cmd->frame->hdr; - unsigned long flags; if (cmd->scmd) { cmd->scmd->SCp.ptr = (char *)0; @@ -1082,9 +1079,7 @@ megasas_complete_cmd(struct megasas_instance *instance, struct megasas_cmd *cmd, if (exception) { - spin_lock_irqsave(&instance->instance_lock, flags); - instance->fw_outstanding--; - spin_unlock_irqrestore(&instance->instance_lock, flags); + atomic_dec(&instance->fw_outstanding); megasas_unmap_sgbuf(instance, cmd); cmd->scmd->scsi_done(cmd->scmd); @@ -1132,9 +1127,7 @@ megasas_complete_cmd(struct megasas_instance *instance, struct megasas_cmd *cmd, break; } - spin_lock_irqsave(&instance->instance_lock, flags); - instance->fw_outstanding--; - spin_unlock_irqrestore(&instance->instance_lock, flags); + atomic_dec(&instance->fw_outstanding); megasas_unmap_sgbuf(instance, cmd); cmd->scmd->scsi_done(cmd->scmd); @@ -2171,11 +2164,12 @@ megasas_probe_one(struct pci_dev *pdev, const struct pci_device_id *id) */ INIT_LIST_HEAD(&instance->cmd_pool); + atomic_set(&instance->fw_outstanding,0); + init_waitqueue_head(&instance->int_cmd_wait_q); init_waitqueue_head(&instance->abort_cmd_wait_q); spin_lock_init(&instance->cmd_pool_lock); - spin_lock_init(&instance->instance_lock); sema_init(&instance->aen_mutex, 1); sema_init(&instance->ioctl_sem, MEGASAS_INT_CMDS); diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h index 89639f0c38..927d6ffef0 100644 --- a/drivers/scsi/megaraid/megaraid_sas.h +++ b/drivers/scsi/megaraid/megaraid_sas.h @@ -1077,9 +1077,8 @@ struct megasas_instance { struct pci_dev *pdev; u32 unique_id; - u32 fw_outstanding; + atomic_t fw_outstanding; u32 hw_crit_error; - spinlock_t instance_lock; struct megasas_instance_template *instancet; }; -- 2.39.5