Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 05e9ebbe authored by Sumant Patro's avatar Sumant Patro Committed by James Bottomley
Browse files

[SCSI] megaraid_sas: intercept cmd timeout and throttle io 



eh_timed_out call back (megasas_reset_timer) is used to throttle io
to the adapter when it is called the first time for a scmd.
The MEGASAS_FW_BUSY flag is set and can_queue reduced to 16.
The can_queue is restored from completion routine in following
two conditions : 5 seconds has elapsed and
the # of outstanding cmds in FW is < 17.

Signed-off-by: default avatarSumant Patro <sumant.patro@lsi.com>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@SteelEye.com>
parent 3d9780b9

drivers/scsi/megaraid/megaraid_sas.c

+60 −7
Original line number Diff line number Diff line
@@ -10,7 +10,7 @@ 
 *	   2 of the License, or (at your option) any later version.

 *

 * FILE		: megaraid_sas.c

 * Version	: v00.00.03.10-rc1

 * Version	: v00.00.03.10-rc5

 *

 * Authors:

 *	(email-id : megaraidlinux@lsi.com)
@@ -886,6 +886,7 @@ megasas_queue_command(struct scsi_cmnd *scmd, void (*done) (struct scsi_cmnd *)) 
		goto out_return_cmd;



	cmd->scmd = scmd;

	scmd->SCp.ptr = (char *)cmd;



	/*

	 * Issue the command to the FW
@@ -919,7 +920,7 @@ static int megasas_slave_configure(struct scsi_device *sdev) 
	 * The RAID firmware may require extended timeouts.

	 */

	if (sdev->channel >= MEGASAS_MAX_PD_CHANNELS)

		sdev->timeout = 90 * HZ;

		sdev->timeout = MEGASAS_DEFAULT_CMD_TIMEOUT * HZ;

	return 0;

}
@@ -981,8 +982,8 @@ static int megasas_generic_reset(struct scsi_cmnd *scmd) 


	instance = (struct megasas_instance *)scmd->device->host->hostdata;



	scmd_printk(KERN_NOTICE, scmd, "megasas: RESET -%ld cmd=%x\n",

	       scmd->serial_number, scmd->cmnd[0]);

	scmd_printk(KERN_NOTICE, scmd, "megasas: RESET -%ld cmd=%x retries=%x\n",

		 scmd->serial_number, scmd->cmnd[0], scmd->retries);



	if (instance->hw_crit_error) {

		printk(KERN_ERR "megasas: cannot recover from previous reset "
@@ -999,6 +1000,39 @@ static int megasas_generic_reset(struct scsi_cmnd *scmd) 
	return ret_val;

}



/**

 * megasas_reset_timer - quiesce the adapter if required

 * @scmd:		scsi cmnd

 *

 * Sets the FW busy flag and reduces the host->can_queue if the

 * cmd has not been completed within the timeout period.

 */

static enum

scsi_eh_timer_return megasas_reset_timer(struct scsi_cmnd *scmd)

{

	struct megasas_cmd *cmd = (struct megasas_cmd *)scmd->SCp.ptr;

	struct megasas_instance *instance;

	unsigned long flags;



	if (time_after(jiffies, scmd->jiffies_at_alloc +

				(MEGASAS_DEFAULT_CMD_TIMEOUT * 2) * HZ)) {

		return EH_NOT_HANDLED;

	}



	instance = cmd->instance;

	if (!(instance->flag & MEGASAS_FW_BUSY)) {

		/* FW is busy, throttle IO */

		spin_lock_irqsave(instance->host->host_lock, flags);



		instance->host->can_queue = 16;

		instance->last_time = jiffies;

		instance->flag |= MEGASAS_FW_BUSY;



		spin_unlock_irqrestore(instance->host->host_lock, flags);

	}

	return EH_RESET_TIMER;

}



/**

 * megasas_reset_device -	Device reset handler entry point

 */
@@ -1112,6 +1146,7 @@ static struct scsi_host_template megasas_template = { 
	.eh_device_reset_handler = megasas_reset_device,

	.eh_bus_reset_handler = megasas_reset_bus_host,

	.eh_host_reset_handler = megasas_reset_bus_host,

	.eh_timed_out = megasas_reset_timer,

	.bios_param = megasas_bios_param,

	.use_clustering = ENABLE_CLUSTERING,

};
@@ -1215,9 +1250,8 @@ megasas_complete_cmd(struct megasas_instance *instance, struct megasas_cmd *cmd, 
	int exception = 0;

	struct megasas_header *hdr = &cmd->frame->hdr;



	if (cmd->scmd) {

		cmd->scmd->SCp.ptr = (char *)0;

	}

	if (cmd->scmd)

		cmd->scmd->SCp.ptr = NULL;



	switch (hdr->cmd) {
@@ -1806,6 +1840,7 @@ static void megasas_complete_cmd_dpc(unsigned long instance_addr) 
	u32 context;

	struct megasas_cmd *cmd;

	struct megasas_instance *instance = (struct megasas_instance *)instance_addr;

	unsigned long flags;



	/* If we have already declared adapter dead, donot complete cmds */

	if (instance->hw_crit_error)
@@ -1828,6 +1863,22 @@ static void megasas_complete_cmd_dpc(unsigned long instance_addr) 
	}



	*instance->consumer = producer;



	/*

	 * Check if we can restore can_queue

	 */

	if (instance->flag & MEGASAS_FW_BUSY

		&& time_after(jiffies, instance->last_time + 5 * HZ)

		&& atomic_read(&instance->fw_outstanding) < 17) {



		spin_lock_irqsave(instance->host->host_lock, flags);

		instance->flag &= ~MEGASAS_FW_BUSY;

		instance->host->can_queue =

				instance->max_fw_cmds - MEGASAS_INT_CMDS;



		spin_unlock_irqrestore(instance->host->host_lock, flags);

	}



}



/**
@@ -2398,6 +2449,8 @@ megasas_probe_one(struct pci_dev *pdev, const struct pci_device_id *id) 
	instance->init_id = MEGASAS_DEFAULT_INIT_ID;



	megasas_dbg_lvl = 0;

	instance->flag = 0;

	instance->last_time = 0;



	/*

	 * Initialize MFI Firmware

drivers/scsi/megaraid/megaraid_sas.h

+9 −5
Original line number Diff line number Diff line
@@ -18,9 +18,9 @@ 
/*

 * MegaRAID SAS Driver meta data

 */

#define MEGASAS_VERSION				"00.00.03.10-rc1"

#define MEGASAS_RELDATE				"Feb 14, 2007"

#define MEGASAS_EXT_VERSION			"Wed Feb 14 10:14:25 PST 2007"

#define MEGASAS_VERSION				"00.00.03.10-rc5"

#define MEGASAS_RELDATE				"May 17, 2007"

#define MEGASAS_EXT_VERSION			"Thu May 17 10:09:32 PDT 2007"



/*

 * Device IDs
@@ -539,6 +539,8 @@ struct megasas_ctrl_info { 


#define MEGASAS_DBG_LVL				1



#define MEGASAS_FW_BUSY				1



/*

 * When SCSI mid-layer calls driver's reset routine, driver waits for

 * MEGASAS_RESET_WAIT_TIME seconds for all outstanding IO to complete. Note
@@ -549,8 +551,8 @@ struct megasas_ctrl_info { 
#define MEGASAS_RESET_WAIT_TIME			180

#define MEGASAS_INTERNAL_CMD_WAIT_TIME		180

#define	MEGASAS_RESET_NOTICE_INTERVAL		5



#define MEGASAS_IOCTL_CMD			0

#define MEGASAS_DEFAULT_CMD_TIMEOUT		90



/*

 * FW reports the maximum of number of commands that it can accept (maximum
@@ -1073,7 +1075,6 @@ struct megasas_instance { 
	struct megasas_register_set __iomem *reg_set;



	s8 init_id;

	u8 reserved[3];



	u16 max_num_sge;

	u16 max_fw_cmds;
@@ -1104,6 +1105,9 @@ struct megasas_instance { 


	struct megasas_instance_template *instancet;

	struct tasklet_struct isr_tasklet;



	u8 flag;

	unsigned long last_time;

};



#define MEGASAS_IS_LOGICAL(scp)						\