From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 918C4C433E0 for ; Fri, 8 Jan 2021 00:14:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5A722236F9 for ; Fri, 8 Jan 2021 00:14:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729413AbhAHAOw (ORCPT ); Thu, 7 Jan 2021 19:14:52 -0500 Received: from mx2.suse.de ([195.135.220.15]:59226 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727300AbhAHAOw (ORCPT ); Thu, 7 Jan 2021 19:14:52 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1610064845; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=hu4rSXkvZ1sXcugdUlNC0iqpiJTDdy9XPlTgIh8vy/8=; b=cNtgYIjZFTNqzGTGWnO6lV3d6Ohe83Ru+oYJBLXL+s0I0C5/UAmf8zgfZ1qaaQmUs7Fe3t VX5MGXhRU4m+bWr6TDXA/PR3p/XCJ5ZO2epCH2HJY5imVbW8jwMrpY2M9kOwnw7oXjfwzc IFHOg9vot88b91/+5lMD6boA5DbvSPc= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id A99D5B77D; Fri, 8 Jan 2021 00:14:05 +0000 (UTC) Message-ID: <8912abe0d7b0b39bfe2efff16db58ec888a8d6d6.camel@suse.com> Subject: Re: [PATCH V3 10/25] smartpqi: add stream detection From: Martin Wilck To: Don Brace , Kevin.Barnett@microchip.com, scott.teel@microchip.com, Justin.Lindley@microchip.com, scott.benesh@microchip.com, gerry.morong@microchip.com, mahesh.rajashekhara@microchip.com, hch@infradead.org, jejb@linux.vnet.ibm.com, joseph.szczypek@hpe.com, POSWALD@suse.com Cc: linux-scsi@vger.kernel.org Date: Fri, 08 Jan 2021 01:14:04 +0100 In-Reply-To: <160763251860.26927.14463337801880165741.stgit@brunhilda> References: <160763241302.26927.17487238067261230799.stgit@brunhilda> <160763251860.26927.14463337801880165741.stgit@brunhilda> Content-Type: text/plain; charset="ISO-8859-15" User-Agent: Evolution 3.38.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On Thu, 2020-12-10 at 14:35 -0600, Don Brace wrote: > * Enhance performance by adding sequential stream detection. >   for R5/R6 sequential write requests. >   * Reduce stripe lock contention with full-stripe write >     operations. I suppose that "stripe lock" is used by the firmware? Could you elaborate a bit more how this technique improves performance? > > Reviewed-by: Scott Benesh > Reviewed-by: Scott Teel > Signed-off-by: Don Brace > --- >  drivers/scsi/smartpqi/smartpqi.h      |    8 +++ >  drivers/scsi/smartpqi/smartpqi_init.c |   87 > +++++++++++++++++++++++++++++++-- >  2 files changed, 89 insertions(+), 6 deletions(-) > > diff --git a/drivers/scsi/smartpqi/smartpqi.h > b/drivers/scsi/smartpqi/smartpqi.h > index a5e271dd2742..343f06e44220 100644 > --- a/drivers/scsi/smartpqi/smartpqi.h > +++ b/drivers/scsi/smartpqi/smartpqi.h > @@ -1042,6 +1042,12 @@ struct pqi_scsi_dev_raid_map_data { >   >  #define RAID_CTLR_LUNID                "\0\0\0\0\0\0\0\0" >   > +#define NUM_STREAMS_PER_LUN    8 > + > +struct pqi_stream_data { > +       u64     next_lba; > +       u32     last_accessed; > +}; >   >  struct pqi_scsi_dev { >         int     devtype;                /* as reported by INQUIRY > commmand */ > @@ -1097,6 +1103,7 @@ struct pqi_scsi_dev { >         struct list_head add_list_entry; >         struct list_head delete_list_entry; >   > +       struct pqi_stream_data stream_data[NUM_STREAMS_PER_LUN]; >         atomic_t scsi_cmds_outstanding; >         atomic_t raid_bypass_cnt; >  }; > @@ -1296,6 +1303,7 @@ struct pqi_ctrl_info { >         u8              enable_r5_writes : 1; >         u8              enable_r6_writes : 1; >         u8              lv_drive_type_mix_valid : 1; > +       u8              enable_stream_detection : 1; >   >         u8              ciss_report_log_flags; >         u32             max_transfer_encrypted_sas_sata; > diff --git a/drivers/scsi/smartpqi/smartpqi_init.c > b/drivers/scsi/smartpqi/smartpqi_init.c > index fc8fafab480d..96383d047a88 100644 > --- a/drivers/scsi/smartpqi/smartpqi_init.c > +++ b/drivers/scsi/smartpqi/smartpqi_init.c > @@ -5721,8 +5721,82 @@ void pqi_prep_for_scsi_done(struct scsi_cmnd > *scmd) >         atomic_dec(&device->scsi_cmds_outstanding); >  } >   > -static int pqi_scsi_queue_command(struct Scsi_Host *shost, > +static bool pqi_is_parity_write_stream(struct pqi_ctrl_info > *ctrl_info, >         struct scsi_cmnd *scmd) > +{ > +       u32 oldest_jiffies; > +       u8 lru_index; > +       int i; > +       int rc; > +       struct pqi_scsi_dev *device; > +       struct pqi_stream_data *pqi_stream_data; > +       struct pqi_scsi_dev_raid_map_data rmd; > + > +       if (!ctrl_info->enable_stream_detection) > +               return false; > + > +       rc = pqi_get_aio_lba_and_block_count(scmd, &rmd); > +       if (rc) > +               return false; > + > +       /* Check writes only. */ > +       if (!rmd.is_write) > +               return false; > + > +       device = scmd->device->hostdata; > + > +       /* Check for RAID 5/6 streams. */ > +       if (device->raid_level != SA_RAID_5 && device->raid_level != > SA_RAID_6) > +               return false; > + > +       /* > +        * If controller does not support AIO RAID{5,6} writes, need > to send > +        * requests down non-AIO path. > +        */ > +       if ((device->raid_level == SA_RAID_5 && !ctrl_info- > >enable_r5_writes) || > +               (device->raid_level == SA_RAID_6 && !ctrl_info- > >enable_r6_writes)) > +               return true; > + > +       lru_index = 0; > +       oldest_jiffies = INT_MAX; > +       for (i = 0; i < NUM_STREAMS_PER_LUN; i++) { > +               pqi_stream_data = &device->stream_data[i]; > +               /* > +                * Check for adjacent request or request is within > +                * the previous request. > +                */ > +               if ((pqi_stream_data->next_lba && > +                       rmd.first_block >= pqi_stream_data->next_lba) > && > +                       rmd.first_block <= pqi_stream_data->next_lba > + > +                               rmd.block_cnt) { Here you seem to assume that the previous write had the same block_cnt. What's the justification for that? > +                       pqi_stream_data->next_lba = rmd.first_block + > +                               rmd.block_cnt; > +                       pqi_stream_data->last_accessed = jiffies; > +                       return true; > +               } > + > +               /* unused entry */ > +               if (pqi_stream_data->last_accessed == 0) { > +                       lru_index = i; > +                       break; > +               } > + > +               /* Find entry with oldest last accessed time. */ > +               if (pqi_stream_data->last_accessed <= oldest_jiffies) > { > +                       oldest_jiffies = pqi_stream_data- > >last_accessed; > +                       lru_index = i; > +               } > +       } > + > +       /* Set LRU entry. */ > +       pqi_stream_data = &device->stream_data[lru_index]; > +       pqi_stream_data->last_accessed = jiffies; > +       pqi_stream_data->next_lba = rmd.first_block + rmd.block_cnt; > + > +       return false; > +} > + > +static int pqi_scsi_queue_command(struct Scsi_Host *shost, struct > scsi_cmnd *scmd) >  { >         int rc; >         struct pqi_ctrl_info *ctrl_info; > @@ -5768,11 +5842,12 @@ static int pqi_scsi_queue_command(struct > Scsi_Host *shost, >                 raid_bypassed = false; >                 if (device->raid_bypass_enabled && >                         !blk_rq_is_passthrough(scmd->request)) { > -                       rc = > pqi_raid_bypass_submit_scsi_cmd(ctrl_info, device, > -                               scmd, queue_group); > -                       if (rc == 0 || rc == SCSI_MLQUEUE_HOST_BUSY) > { > -                               raid_bypassed = true; > -                               atomic_inc(&device->raid_bypass_cnt); > +                       if (!pqi_is_parity_write_stream(ctrl_info, > scmd)) { > +                               rc = > pqi_raid_bypass_submit_scsi_cmd(ctrl_info, device, scmd, > queue_group); > +                               if (rc == 0 || rc == > SCSI_MLQUEUE_HOST_BUSY) { > +                                       raid_bypassed = true; > +                                       atomic_inc(&device- > >raid_bypass_cnt); > +                               } >                         } >                 } >                 if (!raid_bypassed) >