| Message ID | 81d66ceaa2763cfc1e5ccb605bb3a4194b947f0d.1574073572.git.baolin.wang7@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add MMC software queue support | expand |
On Mon, Nov 18, 2019 at 11:43 AM Baolin Wang <baolin.wang7@gmail.com> wrote: > > From: Baolin Wang <baolin.wang@linaro.org> > > Now the MMC read/write stack will always wait for previous request is > completed by mmc_blk_rw_wait(), before sending a new request to hardware, > or queue a work to complete request, that will bring context switching > overhead, especially for high I/O per second rates, to affect the IO > performance. > > Thus this patch introduces MMC software queue interface based on the > hardware command queue engine's interfaces, which is similar with the > hardware command queue engine's idea, that can remove the context > switching. Moreover we set the default queue depth as 32 for software > queue, which allows more requests to be prepared, merged and inserted > into IO scheduler to improve performance, but we only allow 2 requests > in flight, that is enough to let the irq handler always trigger the > next request without a context switch, as well as avoiding a long latency. > > From the fio testing data in cover letter, we can see the software > queue can improve some performance with 4K block size, increasing > about 16% for random read, increasing about 90% for random write, > though no obvious improvement for sequential read and write. > > Moreover we can expand the software queue interface to support MMC > packed request or packed command in future. > > Signed-off-by: Baolin Wang <baolin.wang@linaro.org> > Signed-off-by: Baolin Wang <baolin.wang7@gmail.com> Overall, this looks like enough of a win that I think we should just use the current version for the moment, while still working on all the other improvements. My biggest concern is the naming of "software queue", which is a concept that runs against the idea of doing all the heavy lifting, in particular the queueing in bfq. Then again, it does not /actually/ do much queuing at all, beyond preparing a single request so it can fire it off early. Even with the packed command support added in, there is not really any queuing beyond what it has to do anyway. Using the infrastructure that was added for cqe seems like a good compromise, as this already has a way to hand down multiple requests to the hardware and is overall more modern than the existing support. I still think we should do all the other things I mentioned in my earlier reply today, but they can be done as add-ons: - remove all blocking calls from the queue_rq() function: partition-change, retune, etc should become non-blocking operations that return busy in the queue_rq function. - get bfq to send down multiple requests all the way into the device driver, so we don't have to actually queue them here at all to do packed commands - add packed command support - submit cmds from hardirq context if this is advantageous, and move everything else in the irq handler into irqthread context in order to remove all other workqueue and softirq processing from the request processing path. If we can agree on this as the rough plan for the future, feel free to add my Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Hi Arnd, On Fri, Nov 22, 2019 at 6:32 PM Arnd Bergmann <arnd@arndb.de> wrote: > > On Mon, Nov 18, 2019 at 11:43 AM Baolin Wang <baolin.wang7@gmail.com> wrote: > > > > From: Baolin Wang <baolin.wang@linaro.org> > > > > Now the MMC read/write stack will always wait for previous request is > > completed by mmc_blk_rw_wait(), before sending a new request to hardware, > > or queue a work to complete request, that will bring context switching > > overhead, especially for high I/O per second rates, to affect the IO > > performance. > > > > Thus this patch introduces MMC software queue interface based on the > > hardware command queue engine's interfaces, which is similar with the > > hardware command queue engine's idea, that can remove the context > > switching. Moreover we set the default queue depth as 32 for software > > queue, which allows more requests to be prepared, merged and inserted > > into IO scheduler to improve performance, but we only allow 2 requests > > in flight, that is enough to let the irq handler always trigger the > > next request without a context switch, as well as avoiding a long latency. > > > > From the fio testing data in cover letter, we can see the software > > queue can improve some performance with 4K block size, increasing > > about 16% for random read, increasing about 90% for random write, > > though no obvious improvement for sequential read and write. > > > > Moreover we can expand the software queue interface to support MMC > > packed request or packed command in future. > > > > Signed-off-by: Baolin Wang <baolin.wang@linaro.org> > > Signed-off-by: Baolin Wang <baolin.wang7@gmail.com> > > Overall, this looks like enough of a win that I think we should just > use the current version for the moment, while still working on all the > other improvements. > > My biggest concern is the naming of "software queue", which is > a concept that runs against the idea of doing all the heavy lifting, > in particular the queueing in bfq. > > Then again, it does not /actually/ do much queuing at all, beyond > preparing a single request so it can fire it off early. Even with the > packed command support added in, there is not really any queuing > beyond what it has to do anyway. Yes. But can not find any better name until now and 'software queue' was suggested by Adrian. > > Using the infrastructure that was added for cqe seems like a good > compromise, as this already has a way to hand down multiple > requests to the hardware and is overall more modern than the > existing support. > > I still think we should do all the other things I mentioned in my > earlier reply today, but they can be done as add-ons: > > - remove all blocking calls from the queue_rq() function: > partition-change, retune, etc should become non-blocking > operations that return busy in the queue_rq function. > > - get bfq to send down multiple requests all the way into > the device driver, so we don't have to actually queue them > here at all to do packed commands > > - add packed command support > > - submit cmds from hardirq context if this is advantageous, > and move everything else in the irq handler into irqthread > context in order to remove all other workqueue and softirq > processing from the request processing path. > > If we can agree on this as the rough plan for the future, > feel free to add my Yes, I agree with your plan. Thast's what we should do in future. > > Reviewed-by: Arnd Bergmann <arnd@arndb.de> Thanks for your reviewing and good suggestion. Ulf, I am not sure if there is any chance to merge this patch set into V5.5, I've tested for a long time and did not find any resession. Thanks.
Hi Ulf, On Fri, Nov 22, 2019 at 6:42 PM Baolin Wang <baolin.wang7@gmail.com> wrote: > > Hi Arnd, > > On Fri, Nov 22, 2019 at 6:32 PM Arnd Bergmann <arnd@arndb.de> wrote: > > > > On Mon, Nov 18, 2019 at 11:43 AM Baolin Wang <baolin.wang7@gmail.com> wrote: > > > > > > From: Baolin Wang <baolin.wang@linaro.org> > > > > > > Now the MMC read/write stack will always wait for previous request is > > > completed by mmc_blk_rw_wait(), before sending a new request to hardware, > > > or queue a work to complete request, that will bring context switching > > > overhead, especially for high I/O per second rates, to affect the IO > > > performance. > > > > > > Thus this patch introduces MMC software queue interface based on the > > > hardware command queue engine's interfaces, which is similar with the > > > hardware command queue engine's idea, that can remove the context > > > switching. Moreover we set the default queue depth as 32 for software > > > queue, which allows more requests to be prepared, merged and inserted > > > into IO scheduler to improve performance, but we only allow 2 requests > > > in flight, that is enough to let the irq handler always trigger the > > > next request without a context switch, as well as avoiding a long latency. > > > > > > From the fio testing data in cover letter, we can see the software > > > queue can improve some performance with 4K block size, increasing > > > about 16% for random read, increasing about 90% for random write, > > > though no obvious improvement for sequential read and write. > > > > > > Moreover we can expand the software queue interface to support MMC > > > packed request or packed command in future. > > > > > > Signed-off-by: Baolin Wang <baolin.wang@linaro.org> > > > Signed-off-by: Baolin Wang <baolin.wang7@gmail.com> > > > > Overall, this looks like enough of a win that I think we should just > > use the current version for the moment, while still working on all the > > other improvements. > > > > My biggest concern is the naming of "software queue", which is > > a concept that runs against the idea of doing all the heavy lifting, > > in particular the queueing in bfq. > > > > Then again, it does not /actually/ do much queuing at all, beyond > > preparing a single request so it can fire it off early. Even with the > > packed command support added in, there is not really any queuing > > beyond what it has to do anyway. > > Yes. But can not find any better name until now and 'software queue' > was suggested by Adrian. > > > > > Using the infrastructure that was added for cqe seems like a good > > compromise, as this already has a way to hand down multiple > > requests to the hardware and is overall more modern than the > > existing support. > > > > I still think we should do all the other things I mentioned in my > > earlier reply today, but they can be done as add-ons: > > > > - remove all blocking calls from the queue_rq() function: > > partition-change, retune, etc should become non-blocking > > operations that return busy in the queue_rq function. > > > > - get bfq to send down multiple requests all the way into > > the device driver, so we don't have to actually queue them > > here at all to do packed commands > > > > - add packed command support > > > > - submit cmds from hardirq context if this is advantageous, > > and move everything else in the irq handler into irqthread > > context in order to remove all other workqueue and softirq > > processing from the request processing path. > > > > If we can agree on this as the rough plan for the future, > > feel free to add my > > Yes, I agree with your plan. Thast's what we should do in future. > > > > > Reviewed-by: Arnd Bergmann <arnd@arndb.de> > > Thanks for your reviewing and good suggestion. > > Ulf, > > I am not sure if there is any chance to merge this patch set into > V5.5, I've tested for a long time and did not find any resession. > Thanks. Could you apply this patchset if no objection from your side? Or do you need me to rebase and resend? Thanks.
+ linux-mmc On Thu, 19 Dec 2019 at 08:26, (Exiting) Baolin Wang <baolin.wang@linaro.org> wrote: > > Hi Ulf, > > On Fri, 13 Dec 2019 at 09:53, (Exiting) Baolin Wang > <baolin.wang@linaro.org> wrote: > > > > Hi Ulf, > > > > On Thu, 12 Dec 2019 at 23:30, Ulf Hansson <ulf.hansson@linaro.org> wrote: > > > > > > [...] > > > > > > > > > > > Ulf, > > > > > > > > > > > > > > > > I am not sure if there is any chance to merge this patch set into > > > > > > > > V5.5, I've tested for a long time and did not find any resession. > > > > > > > > Thanks. > > > > > > > > > > > > > > Could you apply this patchset if no objection from your side? Or do > > > > > > > you need me to rebase and resend? Thanks. > > > > > > > > > > > > Sorry for troubling you in this way. Just want to make sure you did > > > > > > not miss my V7 patchset for the MMC software queue, since it was > > > > > > pending for a while, and I got a consensus with Arnd and Adrian > > > > > > finally. Could you apply them if no objection from your side? As we > > > > > > talked before, there are some packed request support patches will > > > > > > depend on the MMC software queue. Thanks a lot. > > > > > > > > > > Thanks for reminding me! Apologize for the delays, just been too busy! > > > > > > > > No worries, I understood :) > > > > > > > > > > > > > > Sounds promising! Let me have a closer look, by the end of this week. > > > > > > > > OK. Thank you very much. > > > > > > Baolin, I am looking at your series, but I need some more time. Yes, > > > even more, sorry. > > > > > > I am out most of tomorrow and the entire weekend, so it seems like I > > > will have to continue reviewing on Monday. > > > > Thanks for letting me know the patches' status. OK, no problem. > > > > Apologize for reminding you again. :) > > I know next week will be your holiday, not sure if this patch set will > be still pending for another long time. And the idea of the solution > was discussed with Arnd and you, so I thought we all got a consensus > about how to add the packed request support step by step. Moreover > this patch set will not impact the normal routine without enabling MMC > software queue and I already did lots of stable testing (including > request handling, tuning and recovering). Did you test system suspend/resume, while also having an ongoing file/dd operations towards the mmc/sd card? In any case, I am aware of the consensus - it looks promising. More importantly, I appreciate the work you are doing here. Don't get me wrong on that, even if I am causing these long an unacceptable delays - sorry about that! I have spent most of my reviewing time this week, looking at your series, but it's not a trivial review and I want to take my time to review it thoroughly. And fore sure, I fully respects Arnd and Adrian reviews that is made already. That said, I am sorry to disappoint you, but I am just not ready to apply it yet. In regards to the holidays, don't worry, I will be working. Well, except for those days that are public holidays in Sweden. :-) > > We really want to use the packed request support with adding ADMA3 > transfer mode to improve the IO performance on our platform ASAP, and > I think we still have more work and potential discussion to add the > packed request support (maybe need optimize the blk-mq to support > batch requests handling), but as we discussed before, we should > introduce the MMC software queue first, then I can move on to the next > step. I am sorry again to troubling you. To help you out a bit in regards to this, I have hosted a separate branch in my git tree that have the series applied (based on today's "next" branch). The branch is namned "next_host_sq". I may decide to merge it to next, to get some test coverage, but let's see about that. In any case, feel free to base AMDA3 (packed command) support on the new branch, at least for now. Kind regards Uffe
Hi Ulf, On Thu, 19 Dec 2019 at 23:22, Ulf Hansson <ulf.hansson@linaro.org> wrote: > > + linux-mmc > > On Thu, 19 Dec 2019 at 08:26, (Exiting) Baolin Wang > <baolin.wang@linaro.org> wrote: > > > > Hi Ulf, > > > > On Fri, 13 Dec 2019 at 09:53, (Exiting) Baolin Wang > > <baolin.wang@linaro.org> wrote: > > > > > > Hi Ulf, > > > > > > On Thu, 12 Dec 2019 at 23:30, Ulf Hansson <ulf.hansson@linaro.org> wrote: > > > > > > > > [...] > > > > > > > > > > > > > Ulf, > > > > > > > > > > > > > > > > > > I am not sure if there is any chance to merge this patch set into > > > > > > > > > V5.5, I've tested for a long time and did not find any resession. > > > > > > > > > Thanks. > > > > > > > > > > > > > > > > Could you apply this patchset if no objection from your side? Or do > > > > > > > > you need me to rebase and resend? Thanks. > > > > > > > > > > > > > > Sorry for troubling you in this way. Just want to make sure you did > > > > > > > not miss my V7 patchset for the MMC software queue, since it was > > > > > > > pending for a while, and I got a consensus with Arnd and Adrian > > > > > > > finally. Could you apply them if no objection from your side? As we > > > > > > > talked before, there are some packed request support patches will > > > > > > > depend on the MMC software queue. Thanks a lot. > > > > > > > > > > > > Thanks for reminding me! Apologize for the delays, just been too busy! > > > > > > > > > > No worries, I understood :) > > > > > > > > > > > > > > > > > Sounds promising! Let me have a closer look, by the end of this week. > > > > > > > > > > OK. Thank you very much. > > > > > > > > Baolin, I am looking at your series, but I need some more time. Yes, > > > > even more, sorry. > > > > > > > > I am out most of tomorrow and the entire weekend, so it seems like I > > > > will have to continue reviewing on Monday. > > > > > > Thanks for letting me know the patches' status. OK, no problem. > > > > > > > Apologize for reminding you again. :) > > > > I know next week will be your holiday, not sure if this patch set will > > be still pending for another long time. And the idea of the solution > > was discussed with Arnd and you, so I thought we all got a consensus > > about how to add the packed request support step by step. Moreover > > this patch set will not impact the normal routine without enabling MMC > > software queue and I already did lots of stable testing (including > > request handling, tuning and recovering). > > Did you test system suspend/resume, while also having an ongoing > file/dd operations towards the mmc/sd card? Yes, I did and it can work. > > In any case, I am aware of the consensus - it looks promising. More > importantly, I appreciate the work you are doing here. Don't get me > wrong on that, even if I am causing these long an unacceptable delays > - sorry about that! > > I have spent most of my reviewing time this week, looking at your > series, but it's not a trivial review and I want to take my time to Thanks for spending time on this patch set. > review it thoroughly. And fore sure, I fully respects Arnd and Adrian > reviews that is made already. > > That said, I am sorry to disappoint you, but I am just not ready to > apply it yet. > > In regards to the holidays, don't worry, I will be working. Well, > except for those days that are public holidays in Sweden. :-) > > > > > We really want to use the packed request support with adding ADMA3 > > transfer mode to improve the IO performance on our platform ASAP, and > > I think we still have more work and potential discussion to add the > > packed request support (maybe need optimize the blk-mq to support > > batch requests handling), but as we discussed before, we should > > introduce the MMC software queue first, then I can move on to the next > > step. I am sorry again to troubling you. > > To help you out a bit in regards to this, I have hosted a separate > branch in my git tree that have the series applied (based on today's > "next" branch). The branch is namned "next_host_sq". I may decide to > merge it to next, to get some test coverage, but let's see about that. > > In any case, feel free to base AMDA3 (packed command) support on the > new branch, at least for now. Great, thanks for your help. -- Baolin Wang Best Regards
On Mon, 18 Nov 2019 at 11:43, Baolin Wang <baolin.wang7@gmail.com> wrote: > > From: Baolin Wang <baolin.wang@linaro.org> > > Now the MMC read/write stack will always wait for previous request is > completed by mmc_blk_rw_wait(), before sending a new request to hardware, > or queue a work to complete request, that will bring context switching > overhead, especially for high I/O per second rates, to affect the IO > performance. > > Thus this patch introduces MMC software queue interface based on the > hardware command queue engine's interfaces, which is similar with the > hardware command queue engine's idea, that can remove the context > switching. Moreover we set the default queue depth as 32 for software > queue, which allows more requests to be prepared, merged and inserted > into IO scheduler to improve performance, but we only allow 2 requests > in flight, that is enough to let the irq handler always trigger the > next request without a context switch, as well as avoiding a long latency. > > From the fio testing data in cover letter, we can see the software > queue can improve some performance with 4K block size, increasing > about 16% for random read, increasing about 90% for random write, > though no obvious improvement for sequential read and write. > > Moreover we can expand the software queue interface to support MMC > packed request or packed command in future. > > Signed-off-by: Baolin Wang <baolin.wang@linaro.org> > Signed-off-by: Baolin Wang <baolin.wang7@gmail.com> > --- > drivers/mmc/core/block.c | 61 ++++++++ > drivers/mmc/core/mmc.c | 13 +- > drivers/mmc/core/queue.c | 33 ++++- > drivers/mmc/host/Kconfig | 7 + > drivers/mmc/host/Makefile | 1 + > drivers/mmc/host/mmc_hsq.c | 344 ++++++++++++++++++++++++++++++++++++++++++++ > drivers/mmc/host/mmc_hsq.h | 30 ++++ > include/linux/mmc/host.h | 3 + > 8 files changed, 482 insertions(+), 10 deletions(-) > create mode 100644 drivers/mmc/host/mmc_hsq.c > create mode 100644 drivers/mmc/host/mmc_hsq.h > > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c > index 2c71a43..870462c 100644 > --- a/drivers/mmc/core/block.c > +++ b/drivers/mmc/core/block.c > @@ -168,6 +168,11 @@ struct mmc_rpmb_data { > > static inline int mmc_blk_part_switch(struct mmc_card *card, > unsigned int part_type); > +static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq, > + struct mmc_card *card, > + int disable_multi, > + struct mmc_queue *mq); > +static void mmc_blk_swq_req_done(struct mmc_request *mrq); We have debated whether swq ("software queue") is a good name - and just to confirm, I also don't have a great better suggestion. However, I do like the name of new host interface though, host software queue, "hsq". That makes sense to me. One option, to possibly make the core code more aligned to the hsq interface, could be to stick with the "hsq" acronym for the core layer as well. In other words, the above function (and its new friends introduced in the series) could be renamed to mmc_blk_hsq_req_done(). What do you think about that? > > static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk) > { > @@ -1569,9 +1574,30 @@ static int mmc_blk_cqe_issue_flush(struct mmc_queue *mq, struct request *req) > return mmc_blk_cqe_start_req(mq->card->host, mrq); > } > > +static int mmc_blk_swq_issue_rw_rq(struct mmc_queue *mq, struct request *req) > +{ > + struct mmc_queue_req *mqrq = req_to_mmc_queue_req(req); > + struct mmc_host *host = mq->card->host; > + int err; > + > + mmc_blk_rw_rq_prep(mqrq, mq->card, 0, mq); > + mqrq->brq.mrq.done = mmc_blk_swq_req_done; > + mmc_pre_req(host, &mqrq->brq.mrq); > + > + err = mmc_cqe_start_req(host, &mqrq->brq.mrq); > + if (err) > + mmc_post_req(host, &mqrq->brq.mrq, err); > + > + return err; > +} > + > static int mmc_blk_cqe_issue_rw_rq(struct mmc_queue *mq, struct request *req) > { > struct mmc_queue_req *mqrq = req_to_mmc_queue_req(req); > + struct mmc_host *host = mq->card->host; > + > + if (host->swq_enabled) If we switch to use "hsq", this would then be "hsq_enabled". > + return mmc_blk_swq_issue_rw_rq(mq, req); > > mmc_blk_data_prep(mq, mqrq, 0, NULL, NULL); > > @@ -1957,6 +1983,41 @@ static void mmc_blk_urgent_bkops(struct mmc_queue *mq, > mmc_run_bkops(mq->card); > } > > +static void mmc_blk_swq_req_done(struct mmc_request *mrq) > +{ > + struct mmc_queue_req *mqrq = > + container_of(mrq, struct mmc_queue_req, brq.mrq); > + struct request *req = mmc_queue_req_to_req(mqrq); > + struct request_queue *q = req->q; > + struct mmc_queue *mq = q->queuedata; > + struct mmc_host *host = mq->card->host; > + unsigned long flags; > + > + if (mmc_blk_rq_error(&mqrq->brq) || > + mmc_blk_urgent_bkops_needed(mq, mqrq)) { > + spin_lock_irqsave(&mq->lock, flags); > + mq->recovery_needed = true; > + mq->recovery_req = req; > + spin_unlock_irqrestore(&mq->lock, flags); > + > + host->cqe_ops->cqe_recovery_start(host); > + > + schedule_work(&mq->recovery_work); > + return; > + } > + > + mmc_blk_rw_reset_success(mq, req); > + > + /* > + * Block layer timeouts race with completions which means the normal > + * completion path cannot be used during recovery. > + */ > + if (mq->in_recovery) > + mmc_blk_cqe_complete_rq(mq, req); > + else > + blk_mq_complete_request(req); > +} > + > void mmc_blk_mq_complete(struct request *req) > { > struct mmc_queue *mq = req->q->queuedata; > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > index c880489..8eac1a2 100644 > --- a/drivers/mmc/core/mmc.c > +++ b/drivers/mmc/core/mmc.c > @@ -1852,15 +1852,22 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, > */ > card->reenable_cmdq = card->ext_csd.cmdq_en; > > - if (card->ext_csd.cmdq_en && !host->cqe_enabled) { > + if (host->cqe_ops && !host->cqe_enabled) { The doesn't looks entirely correct to me, as it means enabling the CQE hardware for hosts with MMC_CAP2_CQE set, but no matter of whether the eMMC card really supports CMDQ (or if we failed to enabled CMDQ for the card). More comments below. > err = host->cqe_ops->cqe_enable(host, card); > if (err) { > pr_err("%s: Failed to enable CQE, error %d\n", > mmc_hostname(host), err); > } else { > host->cqe_enabled = true; > - pr_info("%s: Command Queue Engine enabled\n", > - mmc_hostname(host)); > + > + if (card->ext_csd.cmdq_en) { > + pr_info("%s: Command Queue Engine enabled\n", > + mmc_hostname(host)); > + } else { > + host->swq_enabled = true; > + pr_info("%s: Software Queue enabled\n", > + mmc_hostname(host)); A few questions around the above code. 1. Let's assume the host supports MMC_CAP2_CQE, but the eMMC card doesn't support CMDQ. In this case, we still want to allow the host to use the software variant (the hsq) of the interface. In principle that is what the code above already tries to implement, but then you also need to update the support in drivers/mmc/host/cqhci.[ch] to support that dynamically. For example, the ->cqe_enable() callback should check "card->ext_csd.cmdq_en" and adjust its behavior accordingly, depending if the flag has been set or not. 2. I also notice that you are enabling the use of the hsq path, solely for eMMC cards. I am guessing hsq is beneficial to use for SD cards as well, don't you think? Of course, I am fine by enabling that in a step-by-step approach, so no need to add that as a part of $subject patch. Although, at least make it a part of the series. > + } > } > } > > diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c > index 9edc086..d9086c1 100644 > --- a/drivers/mmc/core/queue.c > +++ b/drivers/mmc/core/queue.c > @@ -62,7 +62,7 @@ enum mmc_issue_type mmc_issue_type(struct mmc_queue *mq, struct request *req) > { > struct mmc_host *host = mq->card->host; > > - if (mq->use_cqe) > + if (mq->use_cqe && !host->swq_enabled) > return mmc_cqe_issue_type(host, req); > > if (req_op(req) == REQ_OP_READ || req_op(req) == REQ_OP_WRITE) > @@ -124,12 +124,14 @@ static enum blk_eh_timer_return mmc_mq_timed_out(struct request *req, > { > struct request_queue *q = req->q; > struct mmc_queue *mq = q->queuedata; > + struct mmc_card *card = mq->card; > + struct mmc_host *host = card->host; > unsigned long flags; > int ret; > > spin_lock_irqsave(&mq->lock, flags); > > - if (mq->recovery_needed || !mq->use_cqe) > + if (mq->recovery_needed || !mq->use_cqe || host->swq_enabled) > ret = BLK_EH_RESET_TIMER; > else > ret = mmc_cqe_timed_out(req); > @@ -144,12 +146,13 @@ static void mmc_mq_recovery_handler(struct work_struct *work) > struct mmc_queue *mq = container_of(work, struct mmc_queue, > recovery_work); > struct request_queue *q = mq->queue; > + struct mmc_host *host = mq->card->host; > > mmc_get_card(mq->card, &mq->ctx); > > mq->in_recovery = true; > > - if (mq->use_cqe) > + if (mq->use_cqe && !host->swq_enabled) > mmc_blk_cqe_recovery(mq); > else > mmc_blk_mq_recovery(mq); > @@ -160,6 +163,9 @@ static void mmc_mq_recovery_handler(struct work_struct *work) > mq->recovery_needed = false; > spin_unlock_irq(&mq->lock); > > + if (host->swq_enabled) > + host->cqe_ops->cqe_recovery_finish(host); > + > mmc_put_card(mq->card, &mq->ctx); > > blk_mq_run_hw_queues(q, true); > @@ -279,6 +285,14 @@ static blk_status_t mmc_mq_queue_rq(struct blk_mq_hw_ctx *hctx, > } > break; > case MMC_ISSUE_ASYNC: > + /* > + * For MMC host software queue, we only allow 2 requests in > + * flight to avoid a long latency. > + */ > + if (host->swq_enabled && mq->in_flight[issue_type] > 2) { > + spin_unlock_irq(&mq->lock); > + return BLK_STS_RESOURCE; > + } > break; > default: > /* > @@ -430,11 +444,16 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card) > * The queue depth for CQE must match the hardware because the request > * tag is used to index the hardware queue. > */ > - if (mq->use_cqe) > - mq->tag_set.queue_depth = > - min_t(int, card->ext_csd.cmdq_depth, host->cqe_qdepth); > - else > + if (mq->use_cqe) { > + if (host->swq_enabled) > + mq->tag_set.queue_depth = host->cqe_qdepth; I don't think we need to treat the hsq as special case in regards to the .queue_depth. It should be fine to use the default MMC_QUEUE_DEPTH (64), don't you think? > + else > + mq->tag_set.queue_depth = > + min_t(int, card->ext_csd.cmdq_depth, host->cqe_qdepth); > + } else { > mq->tag_set.queue_depth = MMC_QUEUE_DEPTH; > + } > + > mq->tag_set.numa_node = NUMA_NO_NODE; > mq->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_BLOCKING; > mq->tag_set.nr_hw_queues = 1; > diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig > index 49ea02c..efa4019 100644 > --- a/drivers/mmc/host/Kconfig > +++ b/drivers/mmc/host/Kconfig > @@ -936,6 +936,13 @@ config MMC_CQHCI > > If unsure, say N. > > +config MMC_HSQ > + tristate "MMC Host Software Queue support" > + help > + This selects the Software Queue support. > + > + If unsure, say N. > + > config MMC_TOSHIBA_PCI > tristate "Toshiba Type A SD/MMC Card Interface Driver" > depends on PCI > diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile > index 11c4598..c14b439 100644 > --- a/drivers/mmc/host/Makefile > +++ b/drivers/mmc/host/Makefile > @@ -98,6 +98,7 @@ obj-$(CONFIG_MMC_SDHCI_BRCMSTB) += sdhci-brcmstb.o > obj-$(CONFIG_MMC_SDHCI_OMAP) += sdhci-omap.o > obj-$(CONFIG_MMC_SDHCI_SPRD) += sdhci-sprd.o > obj-$(CONFIG_MMC_CQHCI) += cqhci.o > +obj-$(CONFIG_MMC_HSQ) += mmc_hsq.o > > ifeq ($(CONFIG_CB710_DEBUG),y) > CFLAGS-cb710-mmc += -DDEBUG > diff --git a/drivers/mmc/host/mmc_hsq.c b/drivers/mmc/host/mmc_hsq.c > new file mode 100644 > index 0000000..f5a4f93 > --- /dev/null > +++ b/drivers/mmc/host/mmc_hsq.c > @@ -0,0 +1,344 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * MMC software queue support based on command queue interfaces > + * > + * Copyright (C) 2019 Linaro, Inc. > + * Author: Baolin Wang <baolin.wang@linaro.org> > + */ > + > +#include <linux/mmc/card.h> > +#include <linux/mmc/host.h> > + > +#include "mmc_hsq.h" > + > +#define HSQ_NUM_SLOTS 32 > +#define HSQ_INVALID_TAG HSQ_NUM_SLOTS > + > +static void mmc_hsq_pump_requests(struct mmc_hsq *hsq) > +{ > + struct mmc_host *mmc = hsq->mmc; > + struct hsq_slot *slot; > + unsigned long flags; > + > + spin_lock_irqsave(&hsq->lock, flags); > + > + /* Make sure we are not already running a request now */ > + if (hsq->mrq) { > + spin_unlock_irqrestore(&hsq->lock, flags); > + return; > + } > + > + /* Make sure there are remain requests need to pump */ > + if (!hsq->qcnt || !hsq->enabled) { > + spin_unlock_irqrestore(&hsq->lock, flags); > + return; > + } > + > + slot = &hsq->slot[hsq->next_tag]; > + hsq->mrq = slot->mrq; > + hsq->qcnt--; > + > + spin_unlock_irqrestore(&hsq->lock, flags); > + > + mmc->ops->request(mmc, hsq->mrq); > +} > + > +static void mmc_hsq_update_next_tag(struct mmc_hsq *hsq, int remains) > +{ > + struct hsq_slot *slot; > + int tag; > + > + /* > + * If there are no remain requests in software queue, then set a invalid > + * tag. > + */ > + if (!remains) { > + hsq->next_tag = HSQ_INVALID_TAG; > + return; > + } > + > + /* > + * Increasing the next tag and check if the corresponding request is > + * available, if yes, then we found a candidate request. > + */ > + if (++hsq->next_tag != HSQ_INVALID_TAG) { > + slot = &hsq->slot[hsq->next_tag]; > + if (slot->mrq) > + return; > + } > + > + /* Othersie we should iterate all slots to find a available tag. */ > + for (tag = 0; tag < HSQ_NUM_SLOTS; tag++) { > + slot = &hsq->slot[tag]; > + if (slot->mrq) > + break; > + } > + > + if (tag == HSQ_NUM_SLOTS) > + tag = HSQ_INVALID_TAG; > + > + hsq->next_tag = tag; > +} > + > +static void mmc_hsq_post_request(struct mmc_hsq *hsq) > +{ > + unsigned long flags; > + int remains; > + > + spin_lock_irqsave(&hsq->lock, flags); > + > + remains = hsq->qcnt; > + hsq->mrq = NULL; > + > + /* Update the next available tag to be queued. */ > + mmc_hsq_update_next_tag(hsq, remains); > + > + if (hsq->waiting_for_idle && !remains) { > + hsq->waiting_for_idle = false; > + wake_up(&hsq->wait_queue); > + } > + > + /* Do not pump new request in recovery mode. */ > + if (hsq->recovery_halt) { > + spin_unlock_irqrestore(&hsq->lock, flags); > + return; > + } > + > + spin_unlock_irqrestore(&hsq->lock, flags); > + > + /* > + * Try to pump new request to host controller as fast as possible, > + * after completing previous request. > + */ > + if (remains > 0) > + mmc_hsq_pump_requests(hsq); > +} > + > +/** > + * mmc_hsq_finalize_request - finalize one request if the request is done > + * @mmc: the host controller > + * @mrq: the request need to be finalized > + * > + * Return true if we finalized the corresponding request in software queue, > + * otherwise return false. > + */ > +bool mmc_hsq_finalize_request(struct mmc_host *mmc, struct mmc_request *mrq) > +{ > + struct mmc_hsq *hsq = mmc->cqe_private; > + unsigned long flags; > + > + spin_lock_irqsave(&hsq->lock, flags); > + > + if (!hsq->enabled || !hsq->mrq || hsq->mrq != mrq) { > + spin_unlock_irqrestore(&hsq->lock, flags); > + return false; > + } > + > + /* > + * Clear current completed slot request to make a room for new request. > + */ > + hsq->slot[hsq->next_tag].mrq = NULL; > + > + spin_unlock_irqrestore(&hsq->lock, flags); > + > + mmc_cqe_request_done(mmc, hsq->mrq); > + > + mmc_hsq_post_request(hsq); > + > + return true; > +} > +EXPORT_SYMBOL_GPL(mmc_hsq_finalize_request); > + > +static void mmc_hsq_recovery_start(struct mmc_host *mmc) > +{ > + struct mmc_hsq *hsq = mmc->cqe_private; > + unsigned long flags; > + > + spin_lock_irqsave(&hsq->lock, flags); > + > + hsq->recovery_halt = true; > + > + spin_unlock_irqrestore(&hsq->lock, flags); > +} > + > +static void mmc_hsq_recovery_finish(struct mmc_host *mmc) > +{ > + struct mmc_hsq *hsq = mmc->cqe_private; > + int remains; > + > + spin_lock_irq(&hsq->lock); > + > + hsq->recovery_halt = false; > + remains = hsq->qcnt; > + > + spin_unlock_irq(&hsq->lock); > + > + /* > + * Try to pump new request if there are request pending in software > + * queue after finishing recovery. > + */ > + if (remains > 0) > + mmc_hsq_pump_requests(hsq); > +} > + > +static int mmc_hsq_request(struct mmc_host *mmc, struct mmc_request *mrq) > +{ > + struct mmc_hsq *hsq = mmc->cqe_private; > + int tag = mrq->tag; > + > + spin_lock_irq(&hsq->lock); > + > + if (!hsq->enabled) { > + spin_unlock_irq(&hsq->lock); > + return -ESHUTDOWN; > + } > + > + /* Do not queue any new requests in recovery mode. */ > + if (hsq->recovery_halt) { > + spin_unlock_irq(&hsq->lock); > + return -EBUSY; > + } > + > + hsq->slot[tag].mrq = mrq; > + > + /* > + * Set the next tag as current request tag if no available > + * next tag. > + */ > + if (hsq->next_tag == HSQ_INVALID_TAG) > + hsq->next_tag = tag; > + > + hsq->qcnt++; > + > + spin_unlock_irq(&hsq->lock); > + > + mmc_hsq_pump_requests(hsq); > + > + return 0; > +} > + > +static void mmc_hsq_post_req(struct mmc_host *mmc, struct mmc_request *mrq) > +{ > + if (mmc->ops->post_req) > + mmc->ops->post_req(mmc, mrq, 0); > +} > + > +static bool mmc_hsq_queue_is_idle(struct mmc_hsq *hsq, int *ret) > +{ > + bool is_idle; > + > + spin_lock_irq(&hsq->lock); > + > + is_idle = (!hsq->mrq && !hsq->qcnt) || > + hsq->recovery_halt; > + > + *ret = hsq->recovery_halt ? -EBUSY : 0; > + hsq->waiting_for_idle = !is_idle; > + > + spin_unlock_irq(&hsq->lock); > + > + return is_idle; > +} > + > +static int mmc_hsq_wait_for_idle(struct mmc_host *mmc) > +{ > + struct mmc_hsq *hsq = mmc->cqe_private; > + int ret; > + > + wait_event(hsq->wait_queue, > + mmc_hsq_queue_is_idle(hsq, &ret)); > + > + return ret; > +} > + > +static void mmc_hsq_disable(struct mmc_host *mmc) > +{ > + struct mmc_hsq *hsq = mmc->cqe_private; > + u32 timeout = 500; > + int ret; > + > + spin_lock_irq(&hsq->lock); > + > + if (!hsq->enabled) { > + spin_unlock_irq(&hsq->lock); > + return; > + } > + > + spin_unlock_irq(&hsq->lock); > + > + ret = wait_event_timeout(hsq->wait_queue, > + mmc_hsq_queue_is_idle(hsq, &ret), > + msecs_to_jiffies(timeout)); > + if (ret == 0) { > + pr_warn("could not stop mmc software queue\n"); > + return; > + } > + > + spin_lock_irq(&hsq->lock); > + > + hsq->enabled = false; > + > + spin_unlock_irq(&hsq->lock); > +} > + > +static int mmc_hsq_enable(struct mmc_host *mmc, struct mmc_card *card) > +{ > + struct mmc_hsq *hsq = mmc->cqe_private; > + > + spin_lock_irq(&hsq->lock); > + > + if (hsq->enabled) { > + spin_unlock_irq(&hsq->lock); > + return -EBUSY; > + } > + > + hsq->enabled = true; > + > + spin_unlock_irq(&hsq->lock); > + > + return 0; > +} > + > +static const struct mmc_cqe_ops mmc_hsq_ops = { > + .cqe_enable = mmc_hsq_enable, > + .cqe_disable = mmc_hsq_disable, > + .cqe_request = mmc_hsq_request, > + .cqe_post_req = mmc_hsq_post_req, > + .cqe_wait_for_idle = mmc_hsq_wait_for_idle, > + .cqe_recovery_start = mmc_hsq_recovery_start, > + .cqe_recovery_finish = mmc_hsq_recovery_finish, > +}; > + > +int mmc_hsq_init(struct mmc_hsq *hsq, struct mmc_host *mmc) > +{ > + hsq->num_slots = HSQ_NUM_SLOTS; > + hsq->next_tag = HSQ_INVALID_TAG; > + mmc->cqe_qdepth = HSQ_NUM_SLOTS; > + > + hsq->slot = devm_kcalloc(mmc_dev(mmc), hsq->num_slots, > + sizeof(struct hsq_slot), GFP_KERNEL); > + if (!hsq->slot) > + return -ENOMEM; > + > + hsq->mmc = mmc; > + hsq->mmc->cqe_private = hsq; > + mmc->cqe_ops = &mmc_hsq_ops; > + > + spin_lock_init(&hsq->lock); > + init_waitqueue_head(&hsq->wait_queue); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(mmc_hsq_init); > + > +void mmc_hsq_suspend(struct mmc_host *mmc) > +{ > + mmc_hsq_disable(mmc); > +} > +EXPORT_SYMBOL_GPL(mmc_hsq_suspend); > + > +int mmc_hsq_resume(struct mmc_host *mmc) > +{ > + return mmc_hsq_enable(mmc, NULL); > +} > +EXPORT_SYMBOL_GPL(mmc_hsq_resume); > diff --git a/drivers/mmc/host/mmc_hsq.h b/drivers/mmc/host/mmc_hsq.h > new file mode 100644 > index 0000000..d51beb7 > --- /dev/null > +++ b/drivers/mmc/host/mmc_hsq.h > @@ -0,0 +1,30 @@ > +// SPDX-License-Identifier: GPL-2.0 > +#ifndef LINUX_MMC_HSQ_H > +#define LINUX_MMC_HSQ_H > + > +struct hsq_slot { > + struct mmc_request *mrq; > +}; > + > +struct mmc_hsq { > + struct mmc_host *mmc; > + struct mmc_request *mrq; > + wait_queue_head_t wait_queue; > + struct hsq_slot *slot; > + spinlock_t lock; > + > + int next_tag; > + int num_slots; > + int qcnt; > + > + bool enabled; > + bool waiting_for_idle; > + bool recovery_halt; > +}; > + > +int mmc_hsq_init(struct mmc_hsq *hsq, struct mmc_host *mmc); > +void mmc_hsq_suspend(struct mmc_host *mmc); > +int mmc_hsq_resume(struct mmc_host *mmc); > +bool mmc_hsq_finalize_request(struct mmc_host *mmc, struct mmc_request *mrq); > + > +#endif > diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h > index ba70338..3931aa3 100644 > --- a/include/linux/mmc/host.h > +++ b/include/linux/mmc/host.h > @@ -462,6 +462,9 @@ struct mmc_host { > bool cqe_enabled; > bool cqe_on; > > + /* Software Queue support */ > + bool swq_enabled; > + > unsigned long private[0] ____cacheline_aligned; > }; > > -- > 1.7.9.5 > Other than the above, this looks indeed very promising! I have no further comment for the rest of the patches in the series. And again, apologize for the delays! Kind regards Uffe
Hi Ulf, (Sorry for the late reply due to my holidays). On Tue, 21 Jan 2020 at 19:52, Ulf Hansson <ulf.hansson@linaro.org> wrote: > > On Mon, 18 Nov 2019 at 11:43, Baolin Wang <baolin.wang7@gmail.com> wrote: > > > > From: Baolin Wang <baolin.wang@linaro.org> > > > > Now the MMC read/write stack will always wait for previous request is > > completed by mmc_blk_rw_wait(), before sending a new request to hardware, > > or queue a work to complete request, that will bring context switching > > overhead, especially for high I/O per second rates, to affect the IO > > performance. > > > > Thus this patch introduces MMC software queue interface based on the > > hardware command queue engine's interfaces, which is similar with the > > hardware command queue engine's idea, that can remove the context > > switching. Moreover we set the default queue depth as 32 for software > > queue, which allows more requests to be prepared, merged and inserted > > into IO scheduler to improve performance, but we only allow 2 requests > > in flight, that is enough to let the irq handler always trigger the > > next request without a context switch, as well as avoiding a long latency. > > > > From the fio testing data in cover letter, we can see the software > > queue can improve some performance with 4K block size, increasing > > about 16% for random read, increasing about 90% for random write, > > though no obvious improvement for sequential read and write. > > > > Moreover we can expand the software queue interface to support MMC > > packed request or packed command in future. > > > > Signed-off-by: Baolin Wang <baolin.wang@linaro.org> > > Signed-off-by: Baolin Wang <baolin.wang7@gmail.com> > > --- > > drivers/mmc/core/block.c | 61 ++++++++ > > drivers/mmc/core/mmc.c | 13 +- > > drivers/mmc/core/queue.c | 33 ++++- > > drivers/mmc/host/Kconfig | 7 + > > drivers/mmc/host/Makefile | 1 + > > drivers/mmc/host/mmc_hsq.c | 344 ++++++++++++++++++++++++++++++++++++++++++++ > > drivers/mmc/host/mmc_hsq.h | 30 ++++ > > include/linux/mmc/host.h | 3 + > > 8 files changed, 482 insertions(+), 10 deletions(-) > > create mode 100644 drivers/mmc/host/mmc_hsq.c > > create mode 100644 drivers/mmc/host/mmc_hsq.h > > > > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c > > index 2c71a43..870462c 100644 > > --- a/drivers/mmc/core/block.c > > +++ b/drivers/mmc/core/block.c > > @@ -168,6 +168,11 @@ struct mmc_rpmb_data { > > > > static inline int mmc_blk_part_switch(struct mmc_card *card, > > unsigned int part_type); > > +static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq, > > + struct mmc_card *card, > > + int disable_multi, > > + struct mmc_queue *mq); > > +static void mmc_blk_swq_req_done(struct mmc_request *mrq); > > We have debated whether swq ("software queue") is a good name - and > just to confirm, I also don't have a great better suggestion. > > However, I do like the name of new host interface though, host > software queue, "hsq". That makes sense to me. > > One option, to possibly make the core code more aligned to the hsq > interface, could be to stick with the "hsq" acronym for the core layer > as well. Sure. > > In other words, the above function (and its new friends introduced in > the series) could be renamed to mmc_blk_hsq_req_done(). What do you > think about that? Yes, totally agree with you. Will change in the next version. > > > > static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk) > > { > > @@ -1569,9 +1574,30 @@ static int mmc_blk_cqe_issue_flush(struct mmc_queue *mq, struct request *req) > > return mmc_blk_cqe_start_req(mq->card->host, mrq); > > } > > > > +static int mmc_blk_swq_issue_rw_rq(struct mmc_queue *mq, struct request *req) > > +{ > > + struct mmc_queue_req *mqrq = req_to_mmc_queue_req(req); > > + struct mmc_host *host = mq->card->host; > > + int err; > > + > > + mmc_blk_rw_rq_prep(mqrq, mq->card, 0, mq); > > + mqrq->brq.mrq.done = mmc_blk_swq_req_done; > > + mmc_pre_req(host, &mqrq->brq.mrq); > > + > > + err = mmc_cqe_start_req(host, &mqrq->brq.mrq); > > + if (err) > > + mmc_post_req(host, &mqrq->brq.mrq, err); > > + > > + return err; > > +} > > + > > static int mmc_blk_cqe_issue_rw_rq(struct mmc_queue *mq, struct request *req) > > { > > struct mmc_queue_req *mqrq = req_to_mmc_queue_req(req); > > + struct mmc_host *host = mq->card->host; > > + > > + if (host->swq_enabled) > > If we switch to use "hsq", this would then be "hsq_enabled". Sure. > > > + return mmc_blk_swq_issue_rw_rq(mq, req); > > > > mmc_blk_data_prep(mq, mqrq, 0, NULL, NULL); > > > > @@ -1957,6 +1983,41 @@ static void mmc_blk_urgent_bkops(struct mmc_queue *mq, > > mmc_run_bkops(mq->card); > > } > > > > +static void mmc_blk_swq_req_done(struct mmc_request *mrq) > > +{ > > + struct mmc_queue_req *mqrq = > > + container_of(mrq, struct mmc_queue_req, brq.mrq); > > + struct request *req = mmc_queue_req_to_req(mqrq); > > + struct request_queue *q = req->q; > > + struct mmc_queue *mq = q->queuedata; > > + struct mmc_host *host = mq->card->host; > > + unsigned long flags; > > + > > + if (mmc_blk_rq_error(&mqrq->brq) || > > + mmc_blk_urgent_bkops_needed(mq, mqrq)) { > > + spin_lock_irqsave(&mq->lock, flags); > > + mq->recovery_needed = true; > > + mq->recovery_req = req; > > + spin_unlock_irqrestore(&mq->lock, flags); > > + > > + host->cqe_ops->cqe_recovery_start(host); > > + > > + schedule_work(&mq->recovery_work); > > + return; > > + } > > + > > + mmc_blk_rw_reset_success(mq, req); > > + > > + /* > > + * Block layer timeouts race with completions which means the normal > > + * completion path cannot be used during recovery. > > + */ > > + if (mq->in_recovery) > > + mmc_blk_cqe_complete_rq(mq, req); > > + else > > + blk_mq_complete_request(req); > > +} > > + > > void mmc_blk_mq_complete(struct request *req) > > { > > struct mmc_queue *mq = req->q->queuedata; > > diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c > > index c880489..8eac1a2 100644 > > --- a/drivers/mmc/core/mmc.c > > +++ b/drivers/mmc/core/mmc.c > > @@ -1852,15 +1852,22 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, > > */ > > card->reenable_cmdq = card->ext_csd.cmdq_en; > > > > - if (card->ext_csd.cmdq_en && !host->cqe_enabled) { > > + if (host->cqe_ops && !host->cqe_enabled) { > > The doesn't looks entirely correct to me, as it means enabling the CQE > hardware for hosts with MMC_CAP2_CQE set, but no matter of whether the > eMMC card really supports CMDQ (or if we failed to enabled CMDQ for > the card). More comments below. > > > err = host->cqe_ops->cqe_enable(host, card); > > if (err) { > > pr_err("%s: Failed to enable CQE, error %d\n", > > mmc_hostname(host), err); > > } else { > > host->cqe_enabled = true; > > - pr_info("%s: Command Queue Engine enabled\n", > > - mmc_hostname(host)); > > + > > + if (card->ext_csd.cmdq_en) { > > + pr_info("%s: Command Queue Engine enabled\n", > > + mmc_hostname(host)); > > + } else { > > + host->swq_enabled = true; > > + pr_info("%s: Software Queue enabled\n", > > + mmc_hostname(host)); > > A few questions around the above code. > > 1. > Let's assume the host supports MMC_CAP2_CQE, but the eMMC card doesn't > support CMDQ. > > In this case, we still want to allow the host to use the software > variant (the hsq) of the interface. In principle that is what the code > above already tries to implement, but then you also need to update the > support in drivers/mmc/host/cqhci.[ch] to support that dynamically. > For example, the ->cqe_enable() callback should check > "card->ext_csd.cmdq_en" and adjust its behavior accordingly, depending > if the flag has been set or not. Right. I will add "card->ext_csd.cmdq_en" checking in drivers/mmc/host/cqhci.c to fix this issue. > 2. > I also notice that you are enabling the use of the hsq path, solely > for eMMC cards. I am guessing hsq is beneficial to use for SD cards as > well, don't you think? Right. > > Of course, I am fine by enabling that in a step-by-step approach, so > no need to add that as a part of $subject patch. Although, at least > make it a part of the series. Yes, that's what I thought. The SD card related patch was already in my local tree, and I will post it if this patch set was accepted. > > > + } > > } > > } > > > > diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c > > index 9edc086..d9086c1 100644 > > --- a/drivers/mmc/core/queue.c > > +++ b/drivers/mmc/core/queue.c > > @@ -62,7 +62,7 @@ enum mmc_issue_type mmc_issue_type(struct mmc_queue *mq, struct request *req) > > { > > struct mmc_host *host = mq->card->host; > > > > - if (mq->use_cqe) > > + if (mq->use_cqe && !host->swq_enabled) > > return mmc_cqe_issue_type(host, req); > > > > if (req_op(req) == REQ_OP_READ || req_op(req) == REQ_OP_WRITE) > > @@ -124,12 +124,14 @@ static enum blk_eh_timer_return mmc_mq_timed_out(struct request *req, > > { > > struct request_queue *q = req->q; > > struct mmc_queue *mq = q->queuedata; > > + struct mmc_card *card = mq->card; > > + struct mmc_host *host = card->host; > > unsigned long flags; > > int ret; > > > > spin_lock_irqsave(&mq->lock, flags); > > > > - if (mq->recovery_needed || !mq->use_cqe) > > + if (mq->recovery_needed || !mq->use_cqe || host->swq_enabled) > > ret = BLK_EH_RESET_TIMER; > > else > > ret = mmc_cqe_timed_out(req); > > @@ -144,12 +146,13 @@ static void mmc_mq_recovery_handler(struct work_struct *work) > > struct mmc_queue *mq = container_of(work, struct mmc_queue, > > recovery_work); > > struct request_queue *q = mq->queue; > > + struct mmc_host *host = mq->card->host; > > > > mmc_get_card(mq->card, &mq->ctx); > > > > mq->in_recovery = true; > > > > - if (mq->use_cqe) > > + if (mq->use_cqe && !host->swq_enabled) > > mmc_blk_cqe_recovery(mq); > > else > > mmc_blk_mq_recovery(mq); > > @@ -160,6 +163,9 @@ static void mmc_mq_recovery_handler(struct work_struct *work) > > mq->recovery_needed = false; > > spin_unlock_irq(&mq->lock); > > > > + if (host->swq_enabled) > > + host->cqe_ops->cqe_recovery_finish(host); > > + > > mmc_put_card(mq->card, &mq->ctx); > > > > blk_mq_run_hw_queues(q, true); > > @@ -279,6 +285,14 @@ static blk_status_t mmc_mq_queue_rq(struct blk_mq_hw_ctx *hctx, > > } > > break; > > case MMC_ISSUE_ASYNC: > > + /* > > + * For MMC host software queue, we only allow 2 requests in > > + * flight to avoid a long latency. > > + */ > > + if (host->swq_enabled && mq->in_flight[issue_type] > 2) { > > + spin_unlock_irq(&mq->lock); > > + return BLK_STS_RESOURCE; > > + } > > break; > > default: > > /* > > @@ -430,11 +444,16 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card) > > * The queue depth for CQE must match the hardware because the request > > * tag is used to index the hardware queue. > > */ > > - if (mq->use_cqe) > > - mq->tag_set.queue_depth = > > - min_t(int, card->ext_csd.cmdq_depth, host->cqe_qdepth); > > - else > > + if (mq->use_cqe) { > > + if (host->swq_enabled) > > + mq->tag_set.queue_depth = host->cqe_qdepth; > > I don't think we need to treat the hsq as special case in regards to > the .queue_depth. > > It should be fine to use the default MMC_QUEUE_DEPTH (64), don't you think? Yes, I agree. > > + else > > + mq->tag_set.queue_depth = > > + min_t(int, card->ext_csd.cmdq_depth, host->cqe_qdepth); > > + } else { > > mq->tag_set.queue_depth = MMC_QUEUE_DEPTH; > > + } > > + > > mq->tag_set.numa_node = NUMA_NO_NODE; > > mq->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_BLOCKING; > > mq->tag_set.nr_hw_queues = 1; > > diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig > > index 49ea02c..efa4019 100644 > > --- a/drivers/mmc/host/Kconfig > > +++ b/drivers/mmc/host/Kconfig > > @@ -936,6 +936,13 @@ config MMC_CQHCI > > > > If unsure, say N. > > > > +config MMC_HSQ > > + tristate "MMC Host Software Queue support" > > + help > > + This selects the Software Queue support. > > + > > + If unsure, say N. > > + > > config MMC_TOSHIBA_PCI > > tristate "Toshiba Type A SD/MMC Card Interface Driver" > > depends on PCI > > diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile > > index 11c4598..c14b439 100644 > > --- a/drivers/mmc/host/Makefile > > +++ b/drivers/mmc/host/Makefile > > @@ -98,6 +98,7 @@ obj-$(CONFIG_MMC_SDHCI_BRCMSTB) += sdhci-brcmstb.o > > obj-$(CONFIG_MMC_SDHCI_OMAP) += sdhci-omap.o > > obj-$(CONFIG_MMC_SDHCI_SPRD) += sdhci-sprd.o > > obj-$(CONFIG_MMC_CQHCI) += cqhci.o > > +obj-$(CONFIG_MMC_HSQ) += mmc_hsq.o > > > > ifeq ($(CONFIG_CB710_DEBUG),y) > > CFLAGS-cb710-mmc += -DDEBUG > > diff --git a/drivers/mmc/host/mmc_hsq.c b/drivers/mmc/host/mmc_hsq.c > > new file mode 100644 > > index 0000000..f5a4f93 > > --- /dev/null > > +++ b/drivers/mmc/host/mmc_hsq.c > > @@ -0,0 +1,344 @@ > > Other than the above, this looks indeed very promising! I have no > further comment for the rest of the patches in the series. Very appreciated for your good suggestion. I will send out the next version after my holidays with addressing your comments. Thanks.
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index 2c71a43..870462c 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -168,6 +168,11 @@ struct mmc_rpmb_data { static inline int mmc_blk_part_switch(struct mmc_card *card, unsigned int part_type); +static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq, + struct mmc_card *card, + int disable_multi, + struct mmc_queue *mq); +static void mmc_blk_swq_req_done(struct mmc_request *mrq); static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk) { @@ -1569,9 +1574,30 @@ static int mmc_blk_cqe_issue_flush(struct mmc_queue *mq, struct request *req) return mmc_blk_cqe_start_req(mq->card->host, mrq); } +static int mmc_blk_swq_issue_rw_rq(struct mmc_queue *mq, struct request *req) +{ + struct mmc_queue_req *mqrq = req_to_mmc_queue_req(req); + struct mmc_host *host = mq->card->host; + int err; + + mmc_blk_rw_rq_prep(mqrq, mq->card, 0, mq); + mqrq->brq.mrq.done = mmc_blk_swq_req_done; + mmc_pre_req(host, &mqrq->brq.mrq); + + err = mmc_cqe_start_req(host, &mqrq->brq.mrq); + if (err) + mmc_post_req(host, &mqrq->brq.mrq, err); + + return err; +} + static int mmc_blk_cqe_issue_rw_rq(struct mmc_queue *mq, struct request *req) { struct mmc_queue_req *mqrq = req_to_mmc_queue_req(req); + struct mmc_host *host = mq->card->host; + + if (host->swq_enabled) + return mmc_blk_swq_issue_rw_rq(mq, req); mmc_blk_data_prep(mq, mqrq, 0, NULL, NULL); @@ -1957,6 +1983,41 @@ static void mmc_blk_urgent_bkops(struct mmc_queue *mq, mmc_run_bkops(mq->card); } +static void mmc_blk_swq_req_done(struct mmc_request *mrq) +{ + struct mmc_queue_req *mqrq = + container_of(mrq, struct mmc_queue_req, brq.mrq); + struct request *req = mmc_queue_req_to_req(mqrq); + struct request_queue *q = req->q; + struct mmc_queue *mq = q->queuedata; + struct mmc_host *host = mq->card->host; + unsigned long flags; + + if (mmc_blk_rq_error(&mqrq->brq) || + mmc_blk_urgent_bkops_needed(mq, mqrq)) { + spin_lock_irqsave(&mq->lock, flags); + mq->recovery_needed = true; + mq->recovery_req = req; + spin_unlock_irqrestore(&mq->lock, flags); + + host->cqe_ops->cqe_recovery_start(host); + + schedule_work(&mq->recovery_work); + return; + } + + mmc_blk_rw_reset_success(mq, req); + + /* + * Block layer timeouts race with completions which means the normal + * completion path cannot be used during recovery. + */ + if (mq->in_recovery) + mmc_blk_cqe_complete_rq(mq, req); + else + blk_mq_complete_request(req); +} + void mmc_blk_mq_complete(struct request *req) { struct mmc_queue *mq = req->q->queuedata; diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index c880489..8eac1a2 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -1852,15 +1852,22 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, */ card->reenable_cmdq = card->ext_csd.cmdq_en; - if (card->ext_csd.cmdq_en && !host->cqe_enabled) { + if (host->cqe_ops && !host->cqe_enabled) { err = host->cqe_ops->cqe_enable(host, card); if (err) { pr_err("%s: Failed to enable CQE, error %d\n", mmc_hostname(host), err); } else { host->cqe_enabled = true; - pr_info("%s: Command Queue Engine enabled\n", - mmc_hostname(host)); + + if (card->ext_csd.cmdq_en) { + pr_info("%s: Command Queue Engine enabled\n", + mmc_hostname(host)); + } else { + host->swq_enabled = true; + pr_info("%s: Software Queue enabled\n", + mmc_hostname(host)); + } } } diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c index 9edc086..d9086c1 100644 --- a/drivers/mmc/core/queue.c +++ b/drivers/mmc/core/queue.c @@ -62,7 +62,7 @@ enum mmc_issue_type mmc_issue_type(struct mmc_queue *mq, struct request *req) { struct mmc_host *host = mq->card->host; - if (mq->use_cqe) + if (mq->use_cqe && !host->swq_enabled) return mmc_cqe_issue_type(host, req); if (req_op(req) == REQ_OP_READ || req_op(req) == REQ_OP_WRITE) @@ -124,12 +124,14 @@ static enum blk_eh_timer_return mmc_mq_timed_out(struct request *req, { struct request_queue *q = req->q; struct mmc_queue *mq = q->queuedata; + struct mmc_card *card = mq->card; + struct mmc_host *host = card->host; unsigned long flags; int ret; spin_lock_irqsave(&mq->lock, flags); - if (mq->recovery_needed || !mq->use_cqe) + if (mq->recovery_needed || !mq->use_cqe || host->swq_enabled) ret = BLK_EH_RESET_TIMER; else ret = mmc_cqe_timed_out(req); @@ -144,12 +146,13 @@ static void mmc_mq_recovery_handler(struct work_struct *work) struct mmc_queue *mq = container_of(work, struct mmc_queue, recovery_work); struct request_queue *q = mq->queue; + struct mmc_host *host = mq->card->host; mmc_get_card(mq->card, &mq->ctx); mq->in_recovery = true; - if (mq->use_cqe) + if (mq->use_cqe && !host->swq_enabled) mmc_blk_cqe_recovery(mq); else mmc_blk_mq_recovery(mq); @@ -160,6 +163,9 @@ static void mmc_mq_recovery_handler(struct work_struct *work) mq->recovery_needed = false; spin_unlock_irq(&mq->lock); + if (host->swq_enabled) + host->cqe_ops->cqe_recovery_finish(host); + mmc_put_card(mq->card, &mq->ctx); blk_mq_run_hw_queues(q, true); @@ -279,6 +285,14 @@ static blk_status_t mmc_mq_queue_rq(struct blk_mq_hw_ctx *hctx, } break; case MMC_ISSUE_ASYNC: + /* + * For MMC host software queue, we only allow 2 requests in + * flight to avoid a long latency. + */ + if (host->swq_enabled && mq->in_flight[issue_type] > 2) { + spin_unlock_irq(&mq->lock); + return BLK_STS_RESOURCE; + } break; default: /* @@ -430,11 +444,16 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card) * The queue depth for CQE must match the hardware because the request * tag is used to index the hardware queue. */ - if (mq->use_cqe) - mq->tag_set.queue_depth = - min_t(int, card->ext_csd.cmdq_depth, host->cqe_qdepth); - else + if (mq->use_cqe) { + if (host->swq_enabled) + mq->tag_set.queue_depth = host->cqe_qdepth; + else + mq->tag_set.queue_depth = + min_t(int, card->ext_csd.cmdq_depth, host->cqe_qdepth); + } else { mq->tag_set.queue_depth = MMC_QUEUE_DEPTH; + } + mq->tag_set.numa_node = NUMA_NO_NODE; mq->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_BLOCKING; mq->tag_set.nr_hw_queues = 1; diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig index 49ea02c..efa4019 100644 --- a/drivers/mmc/host/Kconfig +++ b/drivers/mmc/host/Kconfig @@ -936,6 +936,13 @@ config MMC_CQHCI If unsure, say N. +config MMC_HSQ + tristate "MMC Host Software Queue support" + help + This selects the Software Queue support. + + If unsure, say N. + config MMC_TOSHIBA_PCI tristate "Toshiba Type A SD/MMC Card Interface Driver" depends on PCI diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile index 11c4598..c14b439 100644 --- a/drivers/mmc/host/Makefile +++ b/drivers/mmc/host/Makefile @@ -98,6 +98,7 @@ obj-$(CONFIG_MMC_SDHCI_BRCMSTB) += sdhci-brcmstb.o obj-$(CONFIG_MMC_SDHCI_OMAP) += sdhci-omap.o obj-$(CONFIG_MMC_SDHCI_SPRD) += sdhci-sprd.o obj-$(CONFIG_MMC_CQHCI) += cqhci.o +obj-$(CONFIG_MMC_HSQ) += mmc_hsq.o ifeq ($(CONFIG_CB710_DEBUG),y) CFLAGS-cb710-mmc += -DDEBUG diff --git a/drivers/mmc/host/mmc_hsq.c b/drivers/mmc/host/mmc_hsq.c new file mode 100644 index 0000000..f5a4f93 --- /dev/null +++ b/drivers/mmc/host/mmc_hsq.c @@ -0,0 +1,344 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * MMC software queue support based on command queue interfaces + * + * Copyright (C) 2019 Linaro, Inc. + * Author: Baolin Wang <baolin.wang@linaro.org> + */ + +#include <linux/mmc/card.h> +#include <linux/mmc/host.h> + +#include "mmc_hsq.h" + +#define HSQ_NUM_SLOTS 32 +#define HSQ_INVALID_TAG HSQ_NUM_SLOTS + +static void mmc_hsq_pump_requests(struct mmc_hsq *hsq) +{ + struct mmc_host *mmc = hsq->mmc; + struct hsq_slot *slot; + unsigned long flags; + + spin_lock_irqsave(&hsq->lock, flags); + + /* Make sure we are not already running a request now */ + if (hsq->mrq) { + spin_unlock_irqrestore(&hsq->lock, flags); + return; + } + + /* Make sure there are remain requests need to pump */ + if (!hsq->qcnt || !hsq->enabled) { + spin_unlock_irqrestore(&hsq->lock, flags); + return; + } + + slot = &hsq->slot[hsq->next_tag]; + hsq->mrq = slot->mrq; + hsq->qcnt--; + + spin_unlock_irqrestore(&hsq->lock, flags); + + mmc->ops->request(mmc, hsq->mrq); +} + +static void mmc_hsq_update_next_tag(struct mmc_hsq *hsq, int remains) +{ + struct hsq_slot *slot; + int tag; + + /* + * If there are no remain requests in software queue, then set a invalid + * tag. + */ + if (!remains) { + hsq->next_tag = HSQ_INVALID_TAG; + return; + } + + /* + * Increasing the next tag and check if the corresponding request is + * available, if yes, then we found a candidate request. + */ + if (++hsq->next_tag != HSQ_INVALID_TAG) { + slot = &hsq->slot[hsq->next_tag]; + if (slot->mrq) + return; + } + + /* Othersie we should iterate all slots to find a available tag. */ + for (tag = 0; tag < HSQ_NUM_SLOTS; tag++) { + slot = &hsq->slot[tag]; + if (slot->mrq) + break; + } + + if (tag == HSQ_NUM_SLOTS) + tag = HSQ_INVALID_TAG; + + hsq->next_tag = tag; +} + +static void mmc_hsq_post_request(struct mmc_hsq *hsq) +{ + unsigned long flags; + int remains; + + spin_lock_irqsave(&hsq->lock, flags); + + remains = hsq->qcnt; + hsq->mrq = NULL; + + /* Update the next available tag to be queued. */ + mmc_hsq_update_next_tag(hsq, remains); + + if (hsq->waiting_for_idle && !remains) { + hsq->waiting_for_idle = false; + wake_up(&hsq->wait_queue); + } + + /* Do not pump new request in recovery mode. */ + if (hsq->recovery_halt) { + spin_unlock_irqrestore(&hsq->lock, flags); + return; + } + + spin_unlock_irqrestore(&hsq->lock, flags); + + /* + * Try to pump new request to host controller as fast as possible, + * after completing previous request. + */ + if (remains > 0) + mmc_hsq_pump_requests(hsq); +} + +/** + * mmc_hsq_finalize_request - finalize one request if the request is done + * @mmc: the host controller + * @mrq: the request need to be finalized + * + * Return true if we finalized the corresponding request in software queue, + * otherwise return false. + */ +bool mmc_hsq_finalize_request(struct mmc_host *mmc, struct mmc_request *mrq) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + unsigned long flags; + + spin_lock_irqsave(&hsq->lock, flags); + + if (!hsq->enabled || !hsq->mrq || hsq->mrq != mrq) { + spin_unlock_irqrestore(&hsq->lock, flags); + return false; + } + + /* + * Clear current completed slot request to make a room for new request. + */ + hsq->slot[hsq->next_tag].mrq = NULL; + + spin_unlock_irqrestore(&hsq->lock, flags); + + mmc_cqe_request_done(mmc, hsq->mrq); + + mmc_hsq_post_request(hsq); + + return true; +} +EXPORT_SYMBOL_GPL(mmc_hsq_finalize_request); + +static void mmc_hsq_recovery_start(struct mmc_host *mmc) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + unsigned long flags; + + spin_lock_irqsave(&hsq->lock, flags); + + hsq->recovery_halt = true; + + spin_unlock_irqrestore(&hsq->lock, flags); +} + +static void mmc_hsq_recovery_finish(struct mmc_host *mmc) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + int remains; + + spin_lock_irq(&hsq->lock); + + hsq->recovery_halt = false; + remains = hsq->qcnt; + + spin_unlock_irq(&hsq->lock); + + /* + * Try to pump new request if there are request pending in software + * queue after finishing recovery. + */ + if (remains > 0) + mmc_hsq_pump_requests(hsq); +} + +static int mmc_hsq_request(struct mmc_host *mmc, struct mmc_request *mrq) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + int tag = mrq->tag; + + spin_lock_irq(&hsq->lock); + + if (!hsq->enabled) { + spin_unlock_irq(&hsq->lock); + return -ESHUTDOWN; + } + + /* Do not queue any new requests in recovery mode. */ + if (hsq->recovery_halt) { + spin_unlock_irq(&hsq->lock); + return -EBUSY; + } + + hsq->slot[tag].mrq = mrq; + + /* + * Set the next tag as current request tag if no available + * next tag. + */ + if (hsq->next_tag == HSQ_INVALID_TAG) + hsq->next_tag = tag; + + hsq->qcnt++; + + spin_unlock_irq(&hsq->lock); + + mmc_hsq_pump_requests(hsq); + + return 0; +} + +static void mmc_hsq_post_req(struct mmc_host *mmc, struct mmc_request *mrq) +{ + if (mmc->ops->post_req) + mmc->ops->post_req(mmc, mrq, 0); +} + +static bool mmc_hsq_queue_is_idle(struct mmc_hsq *hsq, int *ret) +{ + bool is_idle; + + spin_lock_irq(&hsq->lock); + + is_idle = (!hsq->mrq && !hsq->qcnt) || + hsq->recovery_halt; + + *ret = hsq->recovery_halt ? -EBUSY : 0; + hsq->waiting_for_idle = !is_idle; + + spin_unlock_irq(&hsq->lock); + + return is_idle; +} + +static int mmc_hsq_wait_for_idle(struct mmc_host *mmc) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + int ret; + + wait_event(hsq->wait_queue, + mmc_hsq_queue_is_idle(hsq, &ret)); + + return ret; +} + +static void mmc_hsq_disable(struct mmc_host *mmc) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + u32 timeout = 500; + int ret; + + spin_lock_irq(&hsq->lock); + + if (!hsq->enabled) { + spin_unlock_irq(&hsq->lock); + return; + } + + spin_unlock_irq(&hsq->lock); + + ret = wait_event_timeout(hsq->wait_queue, + mmc_hsq_queue_is_idle(hsq, &ret), + msecs_to_jiffies(timeout)); + if (ret == 0) { + pr_warn("could not stop mmc software queue\n"); + return; + } + + spin_lock_irq(&hsq->lock); + + hsq->enabled = false; + + spin_unlock_irq(&hsq->lock); +} + +static int mmc_hsq_enable(struct mmc_host *mmc, struct mmc_card *card) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + + spin_lock_irq(&hsq->lock); + + if (hsq->enabled) { + spin_unlock_irq(&hsq->lock); + return -EBUSY; + } + + hsq->enabled = true; + + spin_unlock_irq(&hsq->lock); + + return 0; +} + +static const struct mmc_cqe_ops mmc_hsq_ops = { + .cqe_enable = mmc_hsq_enable, + .cqe_disable = mmc_hsq_disable, + .cqe_request = mmc_hsq_request, + .cqe_post_req = mmc_hsq_post_req, + .cqe_wait_for_idle = mmc_hsq_wait_for_idle, + .cqe_recovery_start = mmc_hsq_recovery_start, + .cqe_recovery_finish = mmc_hsq_recovery_finish, +}; + +int mmc_hsq_init(struct mmc_hsq *hsq, struct mmc_host *mmc) +{ + hsq->num_slots = HSQ_NUM_SLOTS; + hsq->next_tag = HSQ_INVALID_TAG; + mmc->cqe_qdepth = HSQ_NUM_SLOTS; + + hsq->slot = devm_kcalloc(mmc_dev(mmc), hsq->num_slots, + sizeof(struct hsq_slot), GFP_KERNEL); + if (!hsq->slot) + return -ENOMEM; + + hsq->mmc = mmc; + hsq->mmc->cqe_private = hsq; + mmc->cqe_ops = &mmc_hsq_ops; + + spin_lock_init(&hsq->lock); + init_waitqueue_head(&hsq->wait_queue); + + return 0; +} +EXPORT_SYMBOL_GPL(mmc_hsq_init); + +void mmc_hsq_suspend(struct mmc_host *mmc) +{ + mmc_hsq_disable(mmc); +} +EXPORT_SYMBOL_GPL(mmc_hsq_suspend); + +int mmc_hsq_resume(struct mmc_host *mmc) +{ + return mmc_hsq_enable(mmc, NULL); +} +EXPORT_SYMBOL_GPL(mmc_hsq_resume); diff --git a/drivers/mmc/host/mmc_hsq.h b/drivers/mmc/host/mmc_hsq.h new file mode 100644 index 0000000..d51beb7 --- /dev/null +++ b/drivers/mmc/host/mmc_hsq.h @@ -0,0 +1,30 @@ +// SPDX-License-Identifier: GPL-2.0 +#ifndef LINUX_MMC_HSQ_H +#define LINUX_MMC_HSQ_H + +struct hsq_slot { + struct mmc_request *mrq; +}; + +struct mmc_hsq { + struct mmc_host *mmc; + struct mmc_request *mrq; + wait_queue_head_t wait_queue; + struct hsq_slot *slot; + spinlock_t lock; + + int next_tag; + int num_slots; + int qcnt; + + bool enabled; + bool waiting_for_idle; + bool recovery_halt; +}; + +int mmc_hsq_init(struct mmc_hsq *hsq, struct mmc_host *mmc); +void mmc_hsq_suspend(struct mmc_host *mmc); +int mmc_hsq_resume(struct mmc_host *mmc); +bool mmc_hsq_finalize_request(struct mmc_host *mmc, struct mmc_request *mrq); + +#endif diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index ba70338..3931aa3 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -462,6 +462,9 @@ struct mmc_host { bool cqe_enabled; bool cqe_on; + /* Software Queue support */ + bool swq_enabled; + unsigned long private[0] ____cacheline_aligned; };