From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sumit Saxena Subject: RE: [PATCH 09/15] megaraid_sas: Dual Queue depth support Date: Tue, 19 Jan 2016 19:14:32 +0530 Message-ID: <54361777a29aaf5a2c81a5456da0de50@mail.gmail.com> References: <1450445228-26571-1-git-send-email-Sumit.Saxena@avagotech.com> <1450445228-26571-10-git-send-email-Sumit.Saxena@avagotech.com> <569E3B51.9070103@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: Received: from mail-lf0-f53.google.com ([209.85.215.53]:36378 "EHLO mail-lf0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754706AbcASNof (ORCPT ); Tue, 19 Jan 2016 08:44:35 -0500 Received: by mail-lf0-f53.google.com with SMTP id h129so144267082lfh.3 for ; Tue, 19 Jan 2016 05:44:34 -0800 (PST) In-Reply-To: <569E3B51.9070103@redhat.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Tomas Henzl , jbottomley@parallels.com, hch@infradead.org, martin.petersen@oracle.com Cc: linux-scsi@vger.kernel.org, Kashyap Desai > -----Original Message----- > From: Tomas Henzl [mailto:thenzl@redhat.com] > Sent: Tuesday, January 19, 2016 7:04 PM > To: Sumit Saxena; jbottomley@parallels.com; hch@infradead.org; > martin.petersen@oracle.com > Cc: linux-scsi@vger.kernel.org; kashyap.desai@avagotech.com > Subject: Re: [PATCH 09/15] megaraid_sas: Dual Queue depth support > > 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 > > Signed-off-by: Kashyap Desai > > --- > > 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@avagotech.com"); > > @@ -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) Agree..I will fix this and send updated patch. > > tomash