Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936428AbcLOPKs (ORCPT ); Thu, 15 Dec 2016 10:10:48 -0500 Received: from mx1.redhat.com ([209.132.183.28]:41336 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758035AbcLOPKp (ORCPT ); Thu, 15 Dec 2016 10:10:45 -0500 Subject: Re: [PATCH V4 08/11] megaraid_sas: Enable or Disable Fast path based on the PCI Threshold Bandwidth To: Sasikumar PC , jejb@kernel.org, hch@infradead.org References: <1481065220-18431-1-git-send-email-sasikumar.pc@broadcom.com> <1481065220-18431-9-git-send-email-sasikumar.pc@broadcom.com> <5e8d0157-51e1-1727-6ebb-2917b0d333c5@redhat.com> <459befddaf0e9f9ad1f597f1037f82ba@mail.gmail.com> Cc: linux-scsi@vger.kernel.org, Sathya Prakash Veerichetty , linux-kernel@vger.kernel.org, Christopher Owens , Kiran Kumar Kasturi From: Tomas Henzl Message-ID: Date: Thu, 15 Dec 2016 16:10:26 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <459befddaf0e9f9ad1f597f1037f82ba@mail.gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Thu, 15 Dec 2016 15:10:29 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 11297 Lines: 314 On 14.12.2016 22:54, Sasikumar PC wrote: > Hi Tomas, > > Please see my response inline > > Thanks > sasi > > -----Original Message----- > From: Tomas Henzl [mailto:thenzl@redhat.com] > Sent: Friday, December 09, 2016 8:59 AM > To: Sasikumar Chandrasekaran; jejb@kernel.org; hch@infradead.org > Cc: linux-scsi@vger.kernel.org; Sathya.Prakash@broadcom.com; > linux-kernel@vger.kernel.org; christopher.owens@broadcom.com; > kiran-kumar.kasturi@broadcom.com > Subject: Re: [PATCH V4 08/11] megaraid_sas: Enable or Disable Fast path > based on the PCI Threshold Bandwidth > > On 7.12.2016 00:00, Sasikumar Chandrasekaran wrote: >> Large SEQ IO workload should sent as non fast path commands >> >> This patch is depending on patch 7 >> >> Signed-off-by: Sasikumar Chandrasekaran >> --- >> drivers/scsi/megaraid/megaraid_sas.h | 8 +++++ >> drivers/scsi/megaraid/megaraid_sas_base.c | 48 > +++++++++++++++++++++++++++++ >> drivers/scsi/megaraid/megaraid_sas_fp.c | 11 +++++-- >> drivers/scsi/megaraid/megaraid_sas_fusion.c | 20 +++++++----- >> drivers/scsi/megaraid/megaraid_sas_fusion.h | 2 +- >> 5 files changed, 78 insertions(+), 11 deletions(-) >> >> diff --git a/drivers/scsi/megaraid/megaraid_sas.h >> b/drivers/scsi/megaraid/megaraid_sas.h >> index 3e087ab..eb5be2b 100644 >> --- a/drivers/scsi/megaraid/megaraid_sas.h >> +++ b/drivers/scsi/megaraid/megaraid_sas.h >> @@ -1429,6 +1429,8 @@ enum FW_BOOT_CONTEXT { >> #define MFI_1068_FW_HANDSHAKE_OFFSET 0x64 >> #define MFI_1068_FW_READY 0xDDDD0000 >> >> +#define MEGASAS_RAID1_FAST_PATH_STATUS_CHECK_INTERVAL HZ >> + >> #define MR_MAX_REPLY_QUEUES_OFFSET 0X0000001F >> #define MR_MAX_REPLY_QUEUES_EXT_OFFSET 0X003FC000 >> #define MR_MAX_REPLY_QUEUES_EXT_OFFSET_SHIFT 14 >> @@ -2101,6 +2103,10 @@ struct megasas_instance { >> atomic_t ldio_outstanding; >> atomic_t fw_reset_no_pci_access; >> >> + atomic64_t bytes_wrote; /* used for raid1 fast path enable or > disable */ >> + atomic_t r1_write_fp_capable; > Is a an atomic variable needed for a just boolean variable? > Sasi - As we need to synchronize timer thread and IO issue threads, > With atomic, at any point of time the value will be definitive. > With boolean, it depends, the value could be in transit while > one thread is reading and other is writing. This explanation is I think not good enough, as a write of a char value is atomic on all architectures. If you need synchronisation you probably need a spinlock. tomash > >> + >> + >> struct megasas_instance_template *instancet; >> struct tasklet_struct isr_tasklet; >> struct work_struct work_init; >> @@ -2143,6 +2149,7 @@ struct megasas_instance { >> long reset_flags; >> struct mutex reset_mutex; >> struct timer_list sriov_heartbeat_timer; >> + struct timer_list r1_fp_hold_timer; >> char skip_heartbeat_timer_del; >> u8 requestorId; >> char PlasmaFW111; >> @@ -2159,6 +2166,7 @@ struct megasas_instance { >> bool is_ventura; >> bool msix_combined; >> u16 max_raid_mapsize; >> + u64 pci_threshold_bandwidth; /* used to control the fp writes */ >> }; >> struct MR_LD_VF_MAP { >> u32 size; >> diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c >> b/drivers/scsi/megaraid/megaraid_sas_base.c >> index 8aafb59..899d25c 100644 >> --- a/drivers/scsi/megaraid/megaraid_sas_base.c >> +++ b/drivers/scsi/megaraid/megaraid_sas_base.c >> @@ -1940,6 +1940,9 @@ void megaraid_sas_kill_hba(struct megasas_instance > *instance) >> } >> /* Complete outstanding ioctls when adapter is killed */ >> megasas_complete_outstanding_ioctls(instance); >> + if (instance->is_ventura) >> + del_timer_sync(&instance->r1_fp_hold_timer); >> + >> } >> >> /** >> @@ -2438,6 +2441,24 @@ void megasas_sriov_heartbeat_handler(unsigned > long instance_addr) >> } >> } >> >> +/*Handler for disabling/enabling raid 1 fast paths*/ void >> +megasas_change_r1_fp_status(unsigned long instance_addr) { >> + struct megasas_instance *instance = >> + (struct megasas_instance *)instance_addr; >> + if (atomic64_read(&instance->bytes_wrote) >= >> + instance->pci_threshold_bandwidth) > { >> + >> + atomic64_set(&instance->bytes_wrote, 0); >> + atomic_set(&instance->r1_write_fp_capable, 0); >> + } else { >> + atomic64_set(&instance->bytes_wrote, 0); >> + atomic_set(&instance->r1_write_fp_capable, 1); >> + } >> + mod_timer(&instance->r1_fp_hold_timer, >> + jiffies + MEGASAS_RAID1_FAST_PATH_STATUS_CHECK_INTERVAL); >> +} >> + >> /** >> * megasas_wait_for_outstanding - Wait for all outstanding cmds >> * @instance: Adapter soft state >> @@ -5371,6 +5392,17 @@ static int megasas_init_fw(struct > megasas_instance *instance) >> instance->skip_heartbeat_timer_del = 1; >> } >> >> + if (instance->is_ventura) { >> + atomic64_set(&instance->bytes_wrote, 0); >> + atomic_set(&instance->r1_write_fp_capable, 1); >> + megasas_start_timer(instance, >> + &instance->r1_fp_hold_timer, >> + megasas_change_r1_fp_status, >> + > MEGASAS_RAID1_FAST_PATH_STATUS_CHECK_INTERVAL); >> + dev_info(&instance->pdev->dev, "starting > the raid 1 fp timer with interval %d\n", >> + > MEGASAS_RAID1_FAST_PATH_STATUS_CHECK_INTERVAL); >> + } >> + >> return 0; >> >> fail_get_ld_pd_list: >> @@ -6161,6 +6193,9 @@ static void megasas_shutdown_controller(struct > megasas_instance *instance, >> if (instance->requestorId && !instance->skip_heartbeat_timer_del) >> del_timer_sync(&instance->sriov_heartbeat_timer); >> >> + if (instance->is_ventura) >> + del_timer_sync(&instance->r1_fp_hold_timer); >> + >> megasas_flush_cache(instance); >> megasas_shutdown_controller(instance, MR_DCMD_HIBERNATE_SHUTDOWN); >> >> @@ -6280,6 +6315,16 @@ static void megasas_shutdown_controller(struct > megasas_instance *instance, >> megasas_setup_jbod_map(instance); >> instance->unload = 0; >> >> + if (instance->is_ventura) { >> + atomic64_set(&instance->bytes_wrote, 0); >> + atomic_set(&instance->r1_write_fp_capable, 1); >> + megasas_start_timer(instance, >> + &instance->r1_fp_hold_timer, >> + megasas_change_r1_fp_status, >> + > MEGASAS_RAID1_FAST_PATH_STATUS_CHECK_INTERVAL); >> + } >> + >> + >> /* >> * Initiate AEN (Asynchronous Event Notification) >> */ >> @@ -6368,6 +6413,9 @@ static void megasas_detach_one(struct pci_dev > *pdev) >> if (instance->requestorId && !instance->skip_heartbeat_timer_del) >> del_timer_sync(&instance->sriov_heartbeat_timer); >> >> + if (instance->is_ventura) >> + del_timer_sync(&instance->r1_fp_hold_timer); >> + >> if (instance->fw_crash_state != UNAVAILABLE) >> megasas_free_host_crash_buffer(instance); >> scsi_remove_host(instance->host); >> diff --git a/drivers/scsi/megaraid/megaraid_sas_fp.c >> b/drivers/scsi/megaraid/megaraid_sas_fp.c >> index a6957a3..7da4685 100644 >> --- a/drivers/scsi/megaraid/megaraid_sas_fp.c >> +++ b/drivers/scsi/megaraid/megaraid_sas_fp.c >> @@ -197,14 +197,19 @@ void MR_PopulateDrvRaidMap(struct >> megasas_instance *instance) >> >> if (instance->max_raid_mapsize) { >> fw_map_dyn = fusion->ld_map[(instance->map_id & 1)]; >> + if (fw_map_dyn->pci_threshold_bandwidth) >> + instance->pci_threshold_bandwidth = >> + le64_to_cpu(fw_map_dyn->pci_threshold_bandwidth); >> #if VD_EXT_DEBUG >> dev_dbg(&instance->pdev->dev, >> " raidMapSize 0x%x fw_map_dyn->descTableOffset 0x%x, " >> - " descTableSize 0x%x descTableNumElements 0x%x\n", >> + " descTableSize 0x%x descTableNumElements 0x%x, " >> + " PCIThreasholdBandwidth %llu\n", >> le32_to_cpu(fw_map_dyn->raid_map_size), >> le32_to_cpu(fw_map_dyn->desc_table_offset), >> le32_to_cpu(fw_map_dyn->desc_table_size), >> - le32_to_cpu(fw_map_dyn->desc_table_num_elements)); >> + le32_to_cpu(fw_map_dyn->desc_table_num_elements), >> + instance->pci_threshold_bandwidth); >> dev_dbg(&instance->pdev->dev, >> "drv map %p ldCount %d\n", drv_map, fw_map_dyn->ld_count); > #endif >> @@ -434,6 +439,8 @@ void MR_PopulateDrvRaidMap(struct megasas_instance > *instance) >> sizeof(struct MR_DEV_HANDLE_INFO) * >> MAX_RAIDMAP_PHYSICAL_DEVICES); >> } >> + if (instance->is_ventura && !instance->pci_threshold_bandwidth) >> + instance->pci_threshold_bandwidth = ULLONG_MAX; >> } >> >> /* >> diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.c >> b/drivers/scsi/megaraid/megaraid_sas_fusion.c >> index f968a23..5992153 100644 >> --- a/drivers/scsi/megaraid/megaraid_sas_fusion.c >> +++ b/drivers/scsi/megaraid/megaraid_sas_fusion.c >> @@ -95,6 +95,7 @@ void megasas_start_timer(struct megasas_instance >> *instance, 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); >> +void megasas_change_r1_fp_status(unsigned long instance_addr); >> >> >> >> @@ -2633,8 +2634,9 @@ void megasas_prepare_secondRaid1_IO(struct > megasas_instance *instance, >> * to get new command >> */ >> if (cmd->is_raid_1_fp_write && >> - atomic_inc_return(&instance->fw_outstanding) > >> - (instance->host->can_queue)) { >> + (atomic_inc_return(&instance->fw_outstanding) > >> + (instance->host->can_queue) || >> + (!atomic_read(&instance->r1_write_fp_capable)))) { >> megasas_fpio_to_ldio(instance, cmd, cmd->scmd); >> atomic_dec(&instance->fw_outstanding); >> } else if (cmd->is_raid_1_fp_write) { @@ -2643,17 +2645,19 @@ void >> megasas_prepare_secondRaid1_IO(struct megasas_instance *instance, >> megasas_prepare_secondRaid1_IO(instance, cmd, r1_cmd); >> } >> >> - >> /* >> - * Issue the command to the FW >> - */ >> + * Issue the command to the FW >> + */ >> + if (scmd->sc_data_direction == PCI_DMA_TODEVICE && > instance->is_ventura) >> + atomic64_add(scsi_bufflen(scmd), &instance->bytes_wrote); > You count the bytes written to the ventura card and based on that it is > asynchronously decided whether the r1_write_fp_capable bit is set in a > timer function. > Please explain what should be achieved with this. > > Sasi - I am working on this and will be posting the update soon > > Thanks, > Tomas > > > > >> megasas_fire_cmd_fusion(instance, req_desc, instance->is_ventura); >> >> - if (r1_cmd) >> + if (r1_cmd) { >> + atomic64_add(scsi_bufflen(scmd), &instance->bytes_wrote); >> megasas_fire_cmd_fusion(instance, r1_cmd->request_desc, >> - instance->is_ventura); >> - >> + instance->is_ventura); >> + } >> >> return 0; >> } >> diff --git a/drivers/scsi/megaraid/megaraid_sas_fusion.h >> b/drivers/scsi/megaraid/megaraid_sas_fusion.h >> index c39c4ed..da05790 100644 >> --- a/drivers/scsi/megaraid/megaraid_sas_fusion.h >> +++ b/drivers/scsi/megaraid/megaraid_sas_fusion.h >> @@ -977,7 +977,7 @@ struct MR_FW_RAID_MAP_DYNAMIC { >> u32 desc_table_size; /* Total Size of desc table */ >> /* Total Number of elements in the desc table */ >> u32 desc_table_num_elements; >> - u64 reserved1; >> + u64 pci_threshold_bandwidth; >> u32 reserved2[3]; /*future use */ >> /* timeout value used by driver in FP IOs */ >> u8 fp_pd_io_timeout_sec; > -- > To unsubscribe from this list: send the line "unsubscribe linux-scsi" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html