Hello James, Is there a time frame when I may see this patch in the scsi-misc tree ? Regards, Sumant -----Original Message----- From: Sumant Patro [mailto:sumant.patro@xxxxxxx] Sent: Wednesday, March 28, 2007 10:44 AM To: James.Bottomley@xxxxxxxxxxxx; akpm@xxxxxxxx; linux-scsi@xxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx; Kolli, Neela; Yang, Bo; Patro, Sumant Subject: [PATCH] scsi: megaraid_sas - intercepts 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: Sumant Patro <sumant.patro@xxxxxxx> --- drivers/scsi/megaraid/megaraid_sas.c | 65 +++++++++++++++++++++++-- drivers/scsi/megaraid/megaraid_sas.h | 13 +++-- 2 files changed, 70 insertions(+), 8 deletions(-) This patch requires the patch submitted by James with subject line : [PATCH] expose eh_timed_out to the host template diff -uprN linux-2.6.orig/drivers/scsi/megaraid/megaraid_sas.c linux-2.6.new/drivers/scsi/megaraid/megaraid_sas.c --- linux-2.6.orig/drivers/scsi/megaraid/megaraid_sas.c 2007-03-28 08:41:49.000000000 -0700 +++ linux-2.6.new/drivers/scsi/megaraid/megaraid_sas.c 2007-03-28 08:36:38.000000000 -0700 @@ -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-rc3 * * Authors: * (email-id : megaraidlinux@xxxxxxx) @@ -886,6 +886,7 @@ megasas_queue_command(struct scsi_cmnd * goto out_return_cmd; cmd->scmd = scmd; + scmd->SCp.ptr = (char *)cmd; /* * Issue the command to the FW @@ -981,8 +982,8 @@ static int megasas_generic_reset(struct 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 " @@ -1000,6 +1001,40 @@ static int megasas_generic_reset(struct } /** + * 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 (cmd) { + if (time_after(jiffies, scmd->jiffies_at_alloc + 170 * HZ)) + return EH_NOT_HANDLED; + + instance = cmd->instance; + if (!(instance->flag & MEGASAS_FW_BUSY)) { + /* FW is busy, throttle IO */ + spin_lock_irqsave(&instance->throttle_io_lock, flags); + + instance->host->can_queue = 16; + instance->last_time = jiffies; + instance->flag |= MEGASAS_FW_BUSY; + + spin_unlock_irqrestore(&instance->throttle_io_lock, flags); + } + return EH_RESET_TIMER; + } + return EH_HANDLED; +} + +/** * megasas_reset_device - Device reset handler entry point */ static int megasas_reset_device(struct scsi_cmnd *scmd) @@ -1112,6 +1147,7 @@ static struct scsi_host_template megasas .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 +1251,8 @@ megasas_complete_cmd(struct megasas_inst int exception = 0; struct megasas_header *hdr = &cmd->frame->hdr; - if (cmd->scmd) { + if (cmd->scmd) cmd->scmd->SCp.ptr = (char *)0; - } switch (hdr->cmd) { @@ -1806,6 +1841,7 @@ static void megasas_complete_cmd_dpc(uns 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 +1864,22 @@ static void megasas_complete_cmd_dpc(uns } *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->throttle_io_lock, flags); + + instance->flag &= ~MEGASAS_FW_BUSY; + instance->host->can_queue = + instance->max_fw_cmds - MEGASAS_INT_CMDS; + + spin_unlock_irqrestore(&instance->throttle_io_lock, flags); + } } /** @@ -2384,6 +2436,7 @@ megasas_probe_one(struct pci_dev *pdev, init_waitqueue_head(&instance->int_cmd_wait_q); init_waitqueue_head(&instance->abort_cmd_wait_q); + spin_lock_init(&instance->throttle_io_lock); spin_lock_init(&instance->cmd_pool_lock); sema_init(&instance->aen_mutex, 1); @@ -2398,6 +2451,8 @@ megasas_probe_one(struct pci_dev *pdev, instance->init_id = MEGASAS_DEFAULT_INIT_ID; megasas_dbg_lvl = 0; + instance->flag = 0; + instance->last_time = 0; /* * Initialize MFI Firmware diff -uprN linux-2.6.orig/drivers/scsi/megaraid/megaraid_sas.h linux-2.6.new/drivers/scsi/megaraid/megaraid_sas.h --- linux-2.6.orig/drivers/scsi/megaraid/megaraid_sas.h 2007-03-28 08:41:49.000000000 -0700 +++ linux-2.6.new/drivers/scsi/megaraid/megaraid_sas.h 2007-03-28 08:36:39.000000000 -0700 @@ -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-rc3" +#define MEGASAS_RELDATE "Mar 28, 2007" +#define MEGASAS_EXT_VERSION "Wed Mar 28 10:25:52 PST 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 @@ -1104,6 +1106,11 @@ struct megasas_instance { struct megasas_instance_template *instancet; struct tasklet_struct isr_tasklet; + + u8 flag; + u8 rsvd[3]; + unsigned long last_time; + spinlock_t throttle_io_lock; }; #define MEGASAS_IS_LOGICAL(scp) \ - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
