On 18.12.2015 14:27, Sumit Saxena wrote: > This patch will add support for Dual Queue depth reported by firmware. > > Below are key points- > > 1. For iMR controllers, firmware will report two queue depths- 1. Controller wide Queue depth 2. LDIO Queue depth(240). > Ofcourse, Controller wide Queue depth will be greater among two. Using this new method, iMR can provide larger Queue depth(QD) > for JBOD and limited QD for Virtual Disk(VD). This feature gives benefit for iMR product which will be used for deployment > with large number of JBOD and limited number of VD on setup. > 2. megaraid_sas driver will throttle Read write LDIOs based when RW LDIOs reaches "LDIO Queue Depth". > 3. This feature of dual queue depth can enabled/disabled via module parameter. Default behavior is: Dual Queue depth is enabled. > 4. Added sysfs parameter "ldio_outstanding" for user to read LDIO outstanding at run time. > > > Signed-off-by: Sumit Saxena <sumit.saxena@xxxxxxxxxxxxx> > Signed-off-by: Kashyap Desai <kashyap.desai@xxxxxxxxxxxxx> > --- > drivers/scsi/megaraid/megaraid_sas.h | 9 +++ > drivers/scsi/megaraid/megaraid_sas_base.c | 20 ++++++- > drivers/scsi/megaraid/megaraid_sas_fusion.c | 89 ++++++++++++++++++++++++--- > 3 files changed, 108 insertions(+), 10 deletions(-) > > diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h > index c539516..4595ef4 100644 > --- a/drivers/scsi/megaraid/megaraid_sas.h > +++ b/drivers/scsi/megaraid/megaraid_sas.h > @@ -1353,6 +1353,12 @@ enum DCMD_TIMEOUT_ACTION { > KILL_ADAPTER = 1, > IGNORE_TIMEOUT = 2, > }; > + > +enum FW_BOOT_CONTEXT { > + PROBE_CONTEXT = 0, > + OCR_CONTEXT = 1, > +}; > + > /* Frame Type */ > #define IO_FRAME 0 > #define PTHRU_FRAME 1 > @@ -2038,6 +2044,8 @@ struct megasas_instance { > u16 max_fw_cmds; > u16 max_mfi_cmds; > u16 max_scsi_cmds; > + u16 ldio_threshold; > + u16 cur_can_queue; > u32 max_sectors_per_req; > struct megasas_aen_event *ev; > > @@ -2068,6 +2076,7 @@ struct megasas_instance { > u32 fw_support_ieee; > > atomic_t fw_outstanding; > + atomic_t ldio_outstanding; > atomic_t fw_reset_no_pci_access; > > struct megasas_instance_template *instancet; > diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c > index 3454c5e..edc26fb 100644 > --- a/drivers/scsi/megaraid/megaraid_sas_base.c > +++ b/drivers/scsi/megaraid/megaraid_sas_base.c > @@ -96,6 +96,10 @@ int rdpq_enable = 1; > module_param(rdpq_enable, int, S_IRUGO); > MODULE_PARM_DESC(rdpq_enable, " Allocate reply queue in chunks for large queue depth enable/disbale Default: disable(0)"); > > +unsigned int dual_qdepth_disable; > +module_param(dual_qdepth_disable, int, S_IRUGO); > +MODULE_PARM_DESC(dual_qdepth_disable, "Disable dual queue depth feature. Default: 0"); > + > MODULE_LICENSE("GPL"); > MODULE_VERSION(MEGASAS_VERSION); > MODULE_AUTHOR("megaraidlinux.pdl@xxxxxxxxxxxxx"); > @@ -1977,7 +1981,7 @@ megasas_check_and_restore_queue_depth(struct megasas_instance *instance) > spin_lock_irqsave(instance->host->host_lock, flags); > instance->flag &= ~MEGASAS_FW_BUSY; > > - instance->host->can_queue = instance->max_scsi_cmds; > + instance->host->can_queue = instance->cur_can_queue; > spin_unlock_irqrestore(instance->host->host_lock, flags); > } > } > @@ -2942,6 +2946,16 @@ megasas_page_size_show(struct device *cdev, > return snprintf(buf, PAGE_SIZE, "%ld\n", (unsigned long)PAGE_SIZE - 1); > } > > +static ssize_t > +megasas_ldio_outstanding_show(struct device *cdev, struct device_attribute *attr, > + char *buf) > +{ > + struct Scsi_Host *shost = class_to_shost(cdev); > + struct megasas_instance *instance = (struct megasas_instance *)shost->hostdata; > + > + return snprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&instance->ldio_outstanding)); > +} > + > static DEVICE_ATTR(fw_crash_buffer, S_IRUGO | S_IWUSR, > megasas_fw_crash_buffer_show, megasas_fw_crash_buffer_store); > static DEVICE_ATTR(fw_crash_buffer_size, S_IRUGO, > @@ -2950,12 +2964,15 @@ static DEVICE_ATTR(fw_crash_state, S_IRUGO | S_IWUSR, > megasas_fw_crash_state_show, megasas_fw_crash_state_store); > static DEVICE_ATTR(page_size, S_IRUGO, > megasas_page_size_show, NULL); > +static DEVICE_ATTR(ldio_outstanding, S_IRUGO, > + megasas_ldio_outstanding_show, NULL); > > struct device_attribute *megaraid_host_attrs[] = { > &dev_attr_fw_crash_buffer_size, > &dev_attr_fw_crash_buffer, > &dev_attr_fw_crash_state, > &dev_attr_page_size, > + &dev_attr_ldio_outstanding, > NULL, > }; > > @@ -4750,6 +4767,7 @@ megasas_init_adapter_mfi(struct megasas_instance *instance) > sema_init(&instance->ioctl_sem, (MEGASAS_MFI_IOCTL_CMDS)); > } > > + instance->cur_can_queue = instance->max_scsi_cmds; > /* > * Create a pool of commands > */ > diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c b/drivers/scsi/megaraid/megaraid_sas_fusion.c > index 9ad779d..7cc7806 100644 > --- a/drivers/scsi/megaraid/megaraid_sas_fusion.c > +++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c > @@ -92,6 +92,7 @@ void megasas_start_timer(struct megasas_instance *instance, > void *fn, unsigned long interval); > extern struct megasas_mgmt_info megasas_mgmt_info; > extern int resetwaittime; > +extern unsigned int dual_qdepth_disable; > static void megasas_free_rdpq_fusion(struct megasas_instance *instance); > static void megasas_free_reply_fusion(struct megasas_instance *instance); > > @@ -208,6 +209,67 @@ megasas_fire_cmd_fusion(struct megasas_instance *instance, > } > > /** > + * megasas_fusion_update_can_queue - Do all Adapter Queue depth related calculations here > + * @instance: Adapter soft state > + * fw_boot_context: Whether this function called during probe or after OCR > + * > + * This function is only for fusion controllers. > + * Update host can queue, if firmware downgrade max supported firmware commands. > + * Firmware upgrade case will be skiped because underlying firmware has > + * more resource than exposed to the OS. > + * > + */ > +static void > +megasas_fusion_update_can_queue(struct megasas_instance *instance, int fw_boot_context) > +{ > + u16 cur_max_fw_cmds = 0; > + u16 ldio_threshold = 0; > + struct megasas_register_set __iomem *reg_set; > + > + reg_set = instance->reg_set; > + > + cur_max_fw_cmds = readl(&instance->reg_set->outbound_scratch_pad_3) & 0x00FFFF; > + > + if (dual_qdepth_disable || !cur_max_fw_cmds) > + cur_max_fw_cmds = instance->instancet->read_fw_status_reg(reg_set) & 0x00FFFF; > + else > + ldio_threshold = > + (instance->instancet->read_fw_status_reg(reg_set) & 0x00FFFF) - MEGASAS_FUSION_IOCTL_CMDS; > + > + dev_info(&instance->pdev->dev, > + "Current firmware maximum commands: %d\t LDIO thershold: %d\n", a typo in "thershold" > + cur_max_fw_cmds, ldio_threshold); > + > + if (fw_boot_context == OCR_CONTEXT) { > + cur_max_fw_cmds = cur_max_fw_cmds - 1; > + if (cur_max_fw_cmds <= instance->max_fw_cmds) { probably '<' instead of '<=" could be here ? > + instance->cur_can_queue = > + cur_max_fw_cmds - (MEGASAS_FUSION_INTERNAL_CMDS + > + MEGASAS_FUSION_IOCTL_CMDS); > + instance->host->can_queue = instance->cur_can_queue; > + instance->ldio_threshold = ldio_threshold; > + } > + } else { > + instance->max_fw_cmds = cur_max_fw_cmds; > + instance->ldio_threshold = ldio_threshold; > + > + if (!instance->is_rdpq) > + instance->max_fw_cmds = min_t(u16, instance->max_fw_cmds, 1024); > + > + /* > + * Reduce the max supported cmds by 1. This is to ensure that the > + * reply_q_sz (1 more than the max cmd that driver may send) > + * does not exceed max cmds that the FW can support > + */ > + instance->max_fw_cmds = instance->max_fw_cmds-1; > + > + instance->max_scsi_cmds = instance->max_fw_cmds - > + (MEGASAS_FUSION_INTERNAL_CMDS + > + MEGASAS_FUSION_IOCTL_CMDS); > + instance->cur_can_queue = instance->max_scsi_cmds; > + } > +} > +/** > * megasas_free_cmds_fusion - Free all the cmds in the free cmd pool > * @instance: Adapter soft state > */ > @@ -736,6 +798,8 @@ megasas_ioc_init_fusion(struct megasas_instance *instance) > drv_ops->mfi_capabilities.support_ext_io_size = 1; > > drv_ops->mfi_capabilities.support_fp_rlbypass = 1; > + if (!dual_qdepth_disable) > + drv_ops->mfi_capabilities.support_ext_queue_depth = 1; > > /* Convert capability to LE32 */ > cpu_to_le32s((u32 *)&init_frame->driver_operations.mfi_capabilities); > @@ -1151,15 +1215,7 @@ megasas_init_adapter_fusion(struct megasas_instance *instance) > > reg_set = instance->reg_set; > > - /* > - * Get various operational parameters from status register > - */ > - instance->max_fw_cmds = > - instance->instancet->read_fw_status_reg(reg_set) & 0x00FFFF; > - dev_info(&instance->pdev->dev, > - "firmware support max fw cmd\t: (%d)\n", instance->max_fw_cmds); > - if (!instance->is_rdpq) > - instance->max_fw_cmds = min_t(u16, instance->max_fw_cmds, 1024); > + megasas_fusion_update_can_queue(instance, PROBE_CONTEXT); > > /* > * Reduce the max supported cmds by 1. This is to ensure that the > @@ -2117,6 +2173,15 @@ megasas_build_and_issue_cmd_fusion(struct megasas_instance *instance, > > fusion = instance->ctrl_context; > > + if (megasas_cmd_type(scmd) == READ_WRITE_LDIO) { > + if (instance->ldio_threshold && > + (atomic_read(&instance->ldio_outstanding) >= > + instance->ldio_threshold)) This test above won't you protect when several processes read the same value in parallel, so it may happen that you get over the limit set for ldio_threshold. (You might use instead a construction with atomic_dec_and_test for example) tomash -- 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