* [PATCH v5 0/4] Enabling ATA Command Priorities
From: Adam Manzanares @ 2016-10-13 23:00 UTC (permalink / raw)
To: axboe, tj, dan.j.williams, hare, martin.petersen, mchristi,
toshi.kani, ming.lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani
Cc: linux-block, linux-ide, linux-kernel, MPT-FusionLinux.pdl,
linux-scsi, Adam Manzanares
This patch builds ATA commands with high priority if the iocontext of a process
is set to real time. The goal of the patch is to improve tail latencies of
workloads that use higher queue depths. This requires setting the iocontext
ioprio on the request when it is initialized.
This patch has been tested with an Ultrastar HE8 HDD and cuts the
the p99.99 tail latency of foreground IO from 2s down to 72ms when
using the deadline scheduler. This patch works independently of the
scheduler so it can be used with all of the currently available
request based schedulers.
Foreground IO, for the previously described results, is an async fio job
submitting 4K read requests at a QD of 1 to the HDD. The foreground IO is set
with the iopriority class of real time. The background workload is another fio
job submitting read requests at a QD of 32 to the same HDD with default
iopriority.
This feature is enabled for ATA devices by setting the ata enable_prio device
attribute to 1. An ATA device is also checked to see if the device supports per
command priority.
v5:
- Updated block patch commit message to explain the why
v4:
- Added blk_rq_set_prio function to associate request prio with ioc prio
- In init_request_from_bio use bio_prio if it is valid
- Removed queue flag used to enable prio
- Added ata enable_prio dev attribute to sysfs to enable prioritized commands
v3:
- Removed null dereference issue in blk-core
- Renamed queue sysfs entries for clarity
- Added documentation for sysfs queue entry
v2:
- Add queue flag to set iopriority going to the request
- If queue flag set, send iopriority class to ata_build_rw_tf
- Remove redundant code in ata_ncq_prio_enabled function.
Adam Manzanares (4):
block: Add iocontext priority to request
fusion: remove iopriority handling
ata: Enabling ATA Command Priorities
ata: ATA Command Priority Disabled By Default
block/blk-core.c | 4 ++-
drivers/ata/libahci.c | 1 +
drivers/ata/libata-core.c | 35 +++++++++++++++++-
drivers/ata/libata-scsi.c | 74 ++++++++++++++++++++++++++++++++++++++-
drivers/ata/libata.h | 2 +-
drivers/message/fusion/mptscsih.c | 5 ---
include/linux/ata.h | 6 ++++
include/linux/blkdev.h | 14 ++++++++
include/linux/libata.h | 26 ++++++++++++++
9 files changed, 158 insertions(+), 9 deletions(-)
--
2.1.4
^ permalink raw reply
* Re: [PATCH v4 2/4] fusion: remove iopriority handling
From: Adam Manzanares @ 2016-10-13 22:12 UTC (permalink / raw)
To: Sathya Prakash Veerichetty
Cc: Adam Manzanares, axboe, tj, dan.j.williams, hare, martin.petersen,
mchristi, toshi.kani, ming.lei, Chaitra Basappa,
Suganath Prabu Subramani, linux-block, linux-ide, linux-kernel,
PDL-MPT-FUSIONLINUX, linux-scsi
In-Reply-To: <8338586db99fd444337d27f9abc3a777@mail.gmail.com>
The 10/13/2016 15:05, Sathya Prakash Veerichetty wrote:
> By removing the code below, we put all the commands for all the types of
> devices (SAS/SATA) as simple-Q (requeue as the device require) and I am
> not sure whether it is the intention of this change.
>
This is the intention of the change. I don't think the iopriority of the
request is being used correctly. What does it mean to use 0x7 as an
indicator that a command should be put at the head of the queue? This
would be clearer if it was using some of the macros from ioprio. If
0x7 means something special I think this should be some #define in the
includes of the fusion driver with some documentation.
> -----Original Message-----
> From: Adam Manzanares [mailto:adam.manzanares@hgst.com]
> Sent: Thursday, October 13, 2016 1:54 PM
> To: axboe@kernel.dk; tj@kernel.org; dan.j.williams@intel.com;
> hare@suse.de; martin.petersen@oracle.com; mchristi@redhat.com;
> toshi.kani@hpe.com; ming.lei@canonical.com; sathya.prakash@broadcom.com;
> chaitra.basappa@broadcom.com; suganath-prabu.subramani@broadcom.com
> Cc: linux-block@vger.kernel.org; linux-ide@vger.kernel.org;
> linux-kernel@vger.kernel.org; MPT-FusionLinux.pdl@broadcom.com;
> linux-scsi@vger.kernel.org; Adam Manzanares; Adam Manzanares
> Subject: [PATCH v4 2/4] fusion: remove iopriority handling
>
> The request priority is now by default coming from the ioc. It was not
> clear what this code was trying to do based upon the iopriority class or
> data. The driver should check that a device supports priorities and use
> them according to the specificiations of ioprio.
>
> Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
> ---
> drivers/message/fusion/mptscsih.c | 5 -----
> 1 file changed, 5 deletions(-)
>
> diff --git a/drivers/message/fusion/mptscsih.c
> b/drivers/message/fusion/mptscsih.c
> index 6c9fc11..4740bb6 100644
> --- a/drivers/message/fusion/mptscsih.c
> +++ b/drivers/message/fusion/mptscsih.c
> @@ -1369,11 +1369,6 @@ mptscsih_qcmd(struct scsi_cmnd *SCpnt)
> if ((vdevice->vtarget->tflags & MPT_TARGET_FLAGS_Q_YES)
> && (SCpnt->device->tagged_supported)) {
> scsictl = scsidir | MPI_SCSIIO_CONTROL_SIMPLEQ;
> - if (SCpnt->request && SCpnt->request->ioprio) {
> - if (((SCpnt->request->ioprio & 0x7) == 1) ||
> - !(SCpnt->request->ioprio & 0x7))
> - scsictl |= MPI_SCSIIO_CONTROL_HEADOFQ;
> - }
> } else
> scsictl = scsidir | MPI_SCSIIO_CONTROL_UNTAGGED;
>
> --
> 2.1.4
>
> Western Digital Corporation (and its subsidiaries) E-mail Confidentiality
> Notice & Disclaimer:
>
> This e-mail and any files transmitted with it may contain confidential or
> legally privileged information of WDC and/or its affiliates, and are
> intended solely for the use of the individual or entity to which they are
> addressed. If you are not the intended recipient, any disclosure, copying,
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Take care,
Adam
^ permalink raw reply
* Re: [PATCH v4 1/4] block: Add iocontext priority to request
From: Adam Manzananares @ 2016-10-13 22:02 UTC (permalink / raw)
To: Jens Axboe
Cc: Dan Williams, Adam Manzanares, Tejun Heo, Hannes Reinecke,
Martin K. Petersen, mchristi, Toshi Kani, Ming Lei,
sathya.prakash, chaitra.basappa, suganath-prabu.subramani,
linux-block, IDE/ATA development list,
linux-kernel@vger.kernel.org, MPT-FusionLinux.pdl, linux-scsi
In-Reply-To: <068e03c4-3558-a6b1-2008-d13bde4958a1@kernel.dk>
The 10/13/2016 14:09, Jens Axboe wrote:
> On 10/13/2016 02:06 PM, Dan Williams wrote:
> >On Thu, Oct 13, 2016 at 12:53 PM, Adam Manzanares
> ><adam.manzanares@hgst.com> wrote:
> >>Patch adds an association between iocontext ioprio and the ioprio of a
> >>request. This value is set in blk_rq_set_prio which takes the request and
> >>the ioc as arguments. If the ioc is valid in blk_rq_set_prio then the
> >>iopriority of the request is set as the iopriority of the ioc. In
> >>init_request_from_bio a check is made to see if the ioprio of the bio is
> >>valid and if so then the request prio comes from the bio.
> >>
> >>Signed-off-by: Adam Manzananares <adam.manzanares@wdc.com>
> >>---
> >> block/blk-core.c | 4 +++-
> >> include/linux/blkdev.h | 14 ++++++++++++++
> >> 2 files changed, 17 insertions(+), 1 deletion(-)
> >>
> >>diff --git a/block/blk-core.c b/block/blk-core.c
> >>index 14d7c07..361b1b9 100644
> >>--- a/block/blk-core.c
> >>+++ b/block/blk-core.c
> >>@@ -1153,6 +1153,7 @@ static struct request *__get_request(struct request_list *rl, int op,
> >>
> >> blk_rq_init(q, rq);
> >> blk_rq_set_rl(rq, rl);
> >>+ blk_rq_set_prio(rq, ioc);
> >> req_set_op_attrs(rq, op, op_flags | REQ_ALLOCED);
> >>
> >> /* init elvpriv */
> >>@@ -1656,7 +1657,8 @@ void init_request_from_bio(struct request *req, struct bio *bio)
> >>
> >> req->errors = 0;
> >> req->__sector = bio->bi_iter.bi_sector;
> >>- req->ioprio = bio_prio(bio);
> >>+ if (ioprio_valid(bio_prio(bio)))
> >>+ req->ioprio = bio_prio(bio);
> >
> >Should we use ioprio_best() here? If req->ioprio and bio_prio()
> >disagree one side has explicitly asked for a higher priority.
>
> It's a good question - but if priority has been set in the bio, it makes
> sense that that would take priority over the general setting for the
> task/io context. So I think the patch is correct as-is.
>
> Adam, you'll want to rewrite the commit message though. A good commit
> message should explain WHY the change is made, not detail the code
> implementation of it.
Got it I'll send something out soon.
>
> --
> Jens Axboe
>
Take care,
Adam
^ permalink raw reply
* Re: [PATCH v4 1/4] block: Add iocontext priority to request
From: Jens Axboe @ 2016-10-13 21:07 UTC (permalink / raw)
To: Dan Williams
Cc: Adam Manzanares, Tejun Heo, Hannes Reinecke, Martin K. Petersen,
mchristi, Toshi Kani, Ming Lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani, linux-block, IDE/ATA development list,
linux-kernel@vger.kernel.org, MPT-FusionLinux.pdl, linux-scsi,
Adam Manzananares
In-Reply-To: <CAPcyv4i1ZgPTfewtpsegdvedc4aEwPDvMNjD97UUAEVZUC-jzQ@mail.gmail.com>
On 10/13/2016 02:59 PM, Dan Williams wrote:
> On Thu, Oct 13, 2016 at 1:24 PM, Jens Axboe <axboe@kernel.dk> wrote:
>> On 10/13/2016 02:19 PM, Dan Williams wrote:
>>>
>>> On Thu, Oct 13, 2016 at 1:09 PM, Jens Axboe <axboe@kernel.dk> wrote:
>>>>
>>>> On 10/13/2016 02:06 PM, Dan Williams wrote:
>>>>>
>>>>>
>>>>> On Thu, Oct 13, 2016 at 12:53 PM, Adam Manzanares
>>>>> <adam.manzanares@hgst.com> wrote:
>>>>>>
>>>>>>
>>>>>> Patch adds an association between iocontext ioprio and the ioprio of a
>>>>>> request. This value is set in blk_rq_set_prio which takes the request
>>>>>> and
>>>>>> the ioc as arguments. If the ioc is valid in blk_rq_set_prio then the
>>>>>> iopriority of the request is set as the iopriority of the ioc. In
>>>>>> init_request_from_bio a check is made to see if the ioprio of the bio
>>>>>> is
>>>>>> valid and if so then the request prio comes from the bio.
>>>>>>
>>>>>> Signed-off-by: Adam Manzananares <adam.manzanares@wdc.com>
>>>>>> ---
>>>>>> block/blk-core.c | 4 +++-
>>>>>> include/linux/blkdev.h | 14 ++++++++++++++
>>>>>> 2 files changed, 17 insertions(+), 1 deletion(-)
>>>>>>
>>>>>> diff --git a/block/blk-core.c b/block/blk-core.c
>>>>>> index 14d7c07..361b1b9 100644
>>>>>> --- a/block/blk-core.c
>>>>>> +++ b/block/blk-core.c
>>>>>> @@ -1153,6 +1153,7 @@ static struct request *__get_request(struct
>>>>>> request_list *rl, int op,
>>>>>>
>>>>>> blk_rq_init(q, rq);
>>>>>> blk_rq_set_rl(rq, rl);
>>>>>> + blk_rq_set_prio(rq, ioc);
>>>>>> req_set_op_attrs(rq, op, op_flags | REQ_ALLOCED);
>>>>>>
>>>>>> /* init elvpriv */
>>>>>> @@ -1656,7 +1657,8 @@ void init_request_from_bio(struct request *req,
>>>>>> struct bio *bio)
>>>>>>
>>>>>> req->errors = 0;
>>>>>> req->__sector = bio->bi_iter.bi_sector;
>>>>>> - req->ioprio = bio_prio(bio);
>>>>>> + if (ioprio_valid(bio_prio(bio)))
>>>>>> + req->ioprio = bio_prio(bio);
>>>>>
>>>>>
>>>>>
>>>>> Should we use ioprio_best() here? If req->ioprio and bio_prio()
>>>>> disagree one side has explicitly asked for a higher priority.
>>>>
>>>>
>>>>
>>>> It's a good question - but if priority has been set in the bio, it makes
>>>> sense that that would take priority over the general setting for the
>>>> task/io context. So I think the patch is correct as-is.
>>>
>>>
>>> Assuming you always trust the kernel to know the right priority...
>>
>>
>> If it set it in the bio, it better know what it's doing. Besides,
>> there's nothing stopping the caller from checking the task priority when
>> it sets it. If we do ioprio_best(), then we are effectively preventing
>> anyone from submitting a bio with a lower priority than the task has
>> generally set.
>
> Ah, that makes sense. Move the ioprio_best() decision out to whatever
> code is setting bio_prio() to allow for cases where the kernel knows
> best.
Yes, precisely.
--
Jens Axboe
^ permalink raw reply
* RE: [PATCH v4 2/4] fusion: remove iopriority handling
From: Sathya Prakash Veerichetty @ 2016-10-13 21:05 UTC (permalink / raw)
To: Adam Manzanares, axboe, tj, dan.j.williams, hare, martin.petersen,
mchristi, toshi.kani, ming.lei, Chaitra Basappa,
Suganath Prabu Subramani
Cc: linux-block, linux-ide, linux-kernel, PDL-MPT-FUSIONLINUX,
linux-scsi, Adam Manzanares
In-Reply-To: <1476388433-2539-3-git-send-email-adam.manzanares@hgst.com>
By removing the code below, we put all the commands for all the types of
devices (SAS/SATA) as simple-Q (requeue as the device require) and I am
not sure whether it is the intention of this change.
-----Original Message-----
From: Adam Manzanares [mailto:adam.manzanares@hgst.com]
Sent: Thursday, October 13, 2016 1:54 PM
To: axboe@kernel.dk; tj@kernel.org; dan.j.williams@intel.com;
hare@suse.de; martin.petersen@oracle.com; mchristi@redhat.com;
toshi.kani@hpe.com; ming.lei@canonical.com; sathya.prakash@broadcom.com;
chaitra.basappa@broadcom.com; suganath-prabu.subramani@broadcom.com
Cc: linux-block@vger.kernel.org; linux-ide@vger.kernel.org;
linux-kernel@vger.kernel.org; MPT-FusionLinux.pdl@broadcom.com;
linux-scsi@vger.kernel.org; Adam Manzanares; Adam Manzanares
Subject: [PATCH v4 2/4] fusion: remove iopriority handling
The request priority is now by default coming from the ioc. It was not
clear what this code was trying to do based upon the iopriority class or
data. The driver should check that a device supports priorities and use
them according to the specificiations of ioprio.
Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
---
drivers/message/fusion/mptscsih.c | 5 -----
1 file changed, 5 deletions(-)
diff --git a/drivers/message/fusion/mptscsih.c
b/drivers/message/fusion/mptscsih.c
index 6c9fc11..4740bb6 100644
--- a/drivers/message/fusion/mptscsih.c
+++ b/drivers/message/fusion/mptscsih.c
@@ -1369,11 +1369,6 @@ mptscsih_qcmd(struct scsi_cmnd *SCpnt)
if ((vdevice->vtarget->tflags & MPT_TARGET_FLAGS_Q_YES)
&& (SCpnt->device->tagged_supported)) {
scsictl = scsidir | MPI_SCSIIO_CONTROL_SIMPLEQ;
- if (SCpnt->request && SCpnt->request->ioprio) {
- if (((SCpnt->request->ioprio & 0x7) == 1) ||
- !(SCpnt->request->ioprio & 0x7))
- scsictl |= MPI_SCSIIO_CONTROL_HEADOFQ;
- }
} else
scsictl = scsidir | MPI_SCSIIO_CONTROL_UNTAGGED;
--
2.1.4
Western Digital Corporation (and its subsidiaries) E-mail Confidentiality
Notice & Disclaimer:
This e-mail and any files transmitted with it may contain confidential or
legally privileged information of WDC and/or its affiliates, and are
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^ permalink raw reply related
* Re: [PATCH v4 1/4] block: Add iocontext priority to request
From: Dan Williams @ 2016-10-13 20:59 UTC (permalink / raw)
To: Jens Axboe
Cc: Adam Manzanares, Tejun Heo, Hannes Reinecke, Martin K. Petersen,
mchristi, Toshi Kani, Ming Lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani, linux-block, IDE/ATA development list,
linux-kernel@vger.kernel.org, MPT-FusionLinux.pdl, linux-scsi,
Adam Manzananares
In-Reply-To: <094ff78d-b410-b2ac-ad60-2af09cf47523@kernel.dk>
On Thu, Oct 13, 2016 at 1:24 PM, Jens Axboe <axboe@kernel.dk> wrote:
> On 10/13/2016 02:19 PM, Dan Williams wrote:
>>
>> On Thu, Oct 13, 2016 at 1:09 PM, Jens Axboe <axboe@kernel.dk> wrote:
>>>
>>> On 10/13/2016 02:06 PM, Dan Williams wrote:
>>>>
>>>>
>>>> On Thu, Oct 13, 2016 at 12:53 PM, Adam Manzanares
>>>> <adam.manzanares@hgst.com> wrote:
>>>>>
>>>>>
>>>>> Patch adds an association between iocontext ioprio and the ioprio of a
>>>>> request. This value is set in blk_rq_set_prio which takes the request
>>>>> and
>>>>> the ioc as arguments. If the ioc is valid in blk_rq_set_prio then the
>>>>> iopriority of the request is set as the iopriority of the ioc. In
>>>>> init_request_from_bio a check is made to see if the ioprio of the bio
>>>>> is
>>>>> valid and if so then the request prio comes from the bio.
>>>>>
>>>>> Signed-off-by: Adam Manzananares <adam.manzanares@wdc.com>
>>>>> ---
>>>>> block/blk-core.c | 4 +++-
>>>>> include/linux/blkdev.h | 14 ++++++++++++++
>>>>> 2 files changed, 17 insertions(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/block/blk-core.c b/block/blk-core.c
>>>>> index 14d7c07..361b1b9 100644
>>>>> --- a/block/blk-core.c
>>>>> +++ b/block/blk-core.c
>>>>> @@ -1153,6 +1153,7 @@ static struct request *__get_request(struct
>>>>> request_list *rl, int op,
>>>>>
>>>>> blk_rq_init(q, rq);
>>>>> blk_rq_set_rl(rq, rl);
>>>>> + blk_rq_set_prio(rq, ioc);
>>>>> req_set_op_attrs(rq, op, op_flags | REQ_ALLOCED);
>>>>>
>>>>> /* init elvpriv */
>>>>> @@ -1656,7 +1657,8 @@ void init_request_from_bio(struct request *req,
>>>>> struct bio *bio)
>>>>>
>>>>> req->errors = 0;
>>>>> req->__sector = bio->bi_iter.bi_sector;
>>>>> - req->ioprio = bio_prio(bio);
>>>>> + if (ioprio_valid(bio_prio(bio)))
>>>>> + req->ioprio = bio_prio(bio);
>>>>
>>>>
>>>>
>>>> Should we use ioprio_best() here? If req->ioprio and bio_prio()
>>>> disagree one side has explicitly asked for a higher priority.
>>>
>>>
>>>
>>> It's a good question - but if priority has been set in the bio, it makes
>>> sense that that would take priority over the general setting for the
>>> task/io context. So I think the patch is correct as-is.
>>
>>
>> Assuming you always trust the kernel to know the right priority...
>
>
> If it set it in the bio, it better know what it's doing. Besides,
> there's nothing stopping the caller from checking the task priority when
> it sets it. If we do ioprio_best(), then we are effectively preventing
> anyone from submitting a bio with a lower priority than the task has
> generally set.
Ah, that makes sense. Move the ioprio_best() decision out to whatever
code is setting bio_prio() to allow for cases where the kernel knows
best.
^ permalink raw reply
* Re: [PATCH v4 1/4] block: Add iocontext priority to request
From: Jens Axboe @ 2016-10-13 20:24 UTC (permalink / raw)
To: Dan Williams
Cc: Adam Manzanares, Tejun Heo, Hannes Reinecke, Martin K. Petersen,
mchristi, Toshi Kani, Ming Lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani, linux-block, IDE/ATA development list,
linux-kernel@vger.kernel.org, MPT-FusionLinux.pdl, linux-scsi,
Adam Manzananares
In-Reply-To: <CAPcyv4jtxp5yFUGqLOmch6EH=CzKtZr4Qb-qnjHb=xLpU5LspQ@mail.gmail.com>
On 10/13/2016 02:19 PM, Dan Williams wrote:
> On Thu, Oct 13, 2016 at 1:09 PM, Jens Axboe <axboe@kernel.dk> wrote:
>> On 10/13/2016 02:06 PM, Dan Williams wrote:
>>>
>>> On Thu, Oct 13, 2016 at 12:53 PM, Adam Manzanares
>>> <adam.manzanares@hgst.com> wrote:
>>>>
>>>> Patch adds an association between iocontext ioprio and the ioprio of a
>>>> request. This value is set in blk_rq_set_prio which takes the request and
>>>> the ioc as arguments. If the ioc is valid in blk_rq_set_prio then the
>>>> iopriority of the request is set as the iopriority of the ioc. In
>>>> init_request_from_bio a check is made to see if the ioprio of the bio is
>>>> valid and if so then the request prio comes from the bio.
>>>>
>>>> Signed-off-by: Adam Manzananares <adam.manzanares@wdc.com>
>>>> ---
>>>> block/blk-core.c | 4 +++-
>>>> include/linux/blkdev.h | 14 ++++++++++++++
>>>> 2 files changed, 17 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/block/blk-core.c b/block/blk-core.c
>>>> index 14d7c07..361b1b9 100644
>>>> --- a/block/blk-core.c
>>>> +++ b/block/blk-core.c
>>>> @@ -1153,6 +1153,7 @@ static struct request *__get_request(struct
>>>> request_list *rl, int op,
>>>>
>>>> blk_rq_init(q, rq);
>>>> blk_rq_set_rl(rq, rl);
>>>> + blk_rq_set_prio(rq, ioc);
>>>> req_set_op_attrs(rq, op, op_flags | REQ_ALLOCED);
>>>>
>>>> /* init elvpriv */
>>>> @@ -1656,7 +1657,8 @@ void init_request_from_bio(struct request *req,
>>>> struct bio *bio)
>>>>
>>>> req->errors = 0;
>>>> req->__sector = bio->bi_iter.bi_sector;
>>>> - req->ioprio = bio_prio(bio);
>>>> + if (ioprio_valid(bio_prio(bio)))
>>>> + req->ioprio = bio_prio(bio);
>>>
>>>
>>> Should we use ioprio_best() here? If req->ioprio and bio_prio()
>>> disagree one side has explicitly asked for a higher priority.
>>
>>
>> It's a good question - but if priority has been set in the bio, it makes
>> sense that that would take priority over the general setting for the
>> task/io context. So I think the patch is correct as-is.
>
> Assuming you always trust the kernel to know the right priority...
If it set it in the bio, it better know what it's doing. Besides,
there's nothing stopping the caller from checking the task priority when
it sets it. If we do ioprio_best(), then we are effectively preventing
anyone from submitting a bio with a lower priority than the task has
generally set.
Now, this depends on the priority being set in req->ioprio is
exclusively inherited from ioc->ioprio. That's the case for file system
requests, but if someone allocated a request and set the priority
otherwise, then ioprio_best() would be correct.
--
Jens Axboe
^ permalink raw reply
* Re: [PATCH v4 1/4] block: Add iocontext priority to request
From: Dan Williams @ 2016-10-13 20:19 UTC (permalink / raw)
To: Jens Axboe
Cc: Adam Manzanares, Tejun Heo, Hannes Reinecke, Martin K. Petersen,
mchristi, Toshi Kani, Ming Lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani, linux-block, IDE/ATA development list,
linux-kernel@vger.kernel.org, MPT-FusionLinux.pdl, linux-scsi,
Adam Manzananares
In-Reply-To: <068e03c4-3558-a6b1-2008-d13bde4958a1@kernel.dk>
On Thu, Oct 13, 2016 at 1:09 PM, Jens Axboe <axboe@kernel.dk> wrote:
> On 10/13/2016 02:06 PM, Dan Williams wrote:
>>
>> On Thu, Oct 13, 2016 at 12:53 PM, Adam Manzanares
>> <adam.manzanares@hgst.com> wrote:
>>>
>>> Patch adds an association between iocontext ioprio and the ioprio of a
>>> request. This value is set in blk_rq_set_prio which takes the request and
>>> the ioc as arguments. If the ioc is valid in blk_rq_set_prio then the
>>> iopriority of the request is set as the iopriority of the ioc. In
>>> init_request_from_bio a check is made to see if the ioprio of the bio is
>>> valid and if so then the request prio comes from the bio.
>>>
>>> Signed-off-by: Adam Manzananares <adam.manzanares@wdc.com>
>>> ---
>>> block/blk-core.c | 4 +++-
>>> include/linux/blkdev.h | 14 ++++++++++++++
>>> 2 files changed, 17 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/block/blk-core.c b/block/blk-core.c
>>> index 14d7c07..361b1b9 100644
>>> --- a/block/blk-core.c
>>> +++ b/block/blk-core.c
>>> @@ -1153,6 +1153,7 @@ static struct request *__get_request(struct
>>> request_list *rl, int op,
>>>
>>> blk_rq_init(q, rq);
>>> blk_rq_set_rl(rq, rl);
>>> + blk_rq_set_prio(rq, ioc);
>>> req_set_op_attrs(rq, op, op_flags | REQ_ALLOCED);
>>>
>>> /* init elvpriv */
>>> @@ -1656,7 +1657,8 @@ void init_request_from_bio(struct request *req,
>>> struct bio *bio)
>>>
>>> req->errors = 0;
>>> req->__sector = bio->bi_iter.bi_sector;
>>> - req->ioprio = bio_prio(bio);
>>> + if (ioprio_valid(bio_prio(bio)))
>>> + req->ioprio = bio_prio(bio);
>>
>>
>> Should we use ioprio_best() here? If req->ioprio and bio_prio()
>> disagree one side has explicitly asked for a higher priority.
>
>
> It's a good question - but if priority has been set in the bio, it makes
> sense that that would take priority over the general setting for the
> task/io context. So I think the patch is correct as-is.
Assuming you always trust the kernel to know the right priority...
^ permalink raw reply
* Re: [PATCH v4 1/4] block: Add iocontext priority to request
From: Jens Axboe @ 2016-10-13 20:09 UTC (permalink / raw)
To: Dan Williams, Adam Manzanares
Cc: Tejun Heo, Hannes Reinecke, Martin K. Petersen, mchristi,
Toshi Kani, Ming Lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani, linux-block, IDE/ATA development list,
linux-kernel@vger.kernel.org, MPT-FusionLinux.pdl, linux-scsi,
Adam Manzananares
In-Reply-To: <CAPcyv4giMwLRkP9YDcOo4st2RqxPXsYYyTOJ2_U8ywQPteM5gQ@mail.gmail.com>
On 10/13/2016 02:06 PM, Dan Williams wrote:
> On Thu, Oct 13, 2016 at 12:53 PM, Adam Manzanares
> <adam.manzanares@hgst.com> wrote:
>> Patch adds an association between iocontext ioprio and the ioprio of a
>> request. This value is set in blk_rq_set_prio which takes the request and
>> the ioc as arguments. If the ioc is valid in blk_rq_set_prio then the
>> iopriority of the request is set as the iopriority of the ioc. In
>> init_request_from_bio a check is made to see if the ioprio of the bio is
>> valid and if so then the request prio comes from the bio.
>>
>> Signed-off-by: Adam Manzananares <adam.manzanares@wdc.com>
>> ---
>> block/blk-core.c | 4 +++-
>> include/linux/blkdev.h | 14 ++++++++++++++
>> 2 files changed, 17 insertions(+), 1 deletion(-)
>>
>> diff --git a/block/blk-core.c b/block/blk-core.c
>> index 14d7c07..361b1b9 100644
>> --- a/block/blk-core.c
>> +++ b/block/blk-core.c
>> @@ -1153,6 +1153,7 @@ static struct request *__get_request(struct request_list *rl, int op,
>>
>> blk_rq_init(q, rq);
>> blk_rq_set_rl(rq, rl);
>> + blk_rq_set_prio(rq, ioc);
>> req_set_op_attrs(rq, op, op_flags | REQ_ALLOCED);
>>
>> /* init elvpriv */
>> @@ -1656,7 +1657,8 @@ void init_request_from_bio(struct request *req, struct bio *bio)
>>
>> req->errors = 0;
>> req->__sector = bio->bi_iter.bi_sector;
>> - req->ioprio = bio_prio(bio);
>> + if (ioprio_valid(bio_prio(bio)))
>> + req->ioprio = bio_prio(bio);
>
> Should we use ioprio_best() here? If req->ioprio and bio_prio()
> disagree one side has explicitly asked for a higher priority.
It's a good question - but if priority has been set in the bio, it makes
sense that that would take priority over the general setting for the
task/io context. So I think the patch is correct as-is.
Adam, you'll want to rewrite the commit message though. A good commit
message should explain WHY the change is made, not detail the code
implementation of it.
--
Jens Axboe
^ permalink raw reply
* Re: [PATCH v4 1/4] block: Add iocontext priority to request
From: Dan Williams @ 2016-10-13 20:06 UTC (permalink / raw)
To: Adam Manzanares
Cc: Jens Axboe, Tejun Heo, Hannes Reinecke, Martin K. Petersen,
mchristi, Toshi Kani, Ming Lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani, linux-block, IDE/ATA development list,
linux-kernel@vger.kernel.org, MPT-FusionLinux.pdl, linux-scsi,
Adam Manzananares
In-Reply-To: <1476388433-2539-2-git-send-email-adam.manzanares@hgst.com>
On Thu, Oct 13, 2016 at 12:53 PM, Adam Manzanares
<adam.manzanares@hgst.com> wrote:
> Patch adds an association between iocontext ioprio and the ioprio of a
> request. This value is set in blk_rq_set_prio which takes the request and
> the ioc as arguments. If the ioc is valid in blk_rq_set_prio then the
> iopriority of the request is set as the iopriority of the ioc. In
> init_request_from_bio a check is made to see if the ioprio of the bio is
> valid and if so then the request prio comes from the bio.
>
> Signed-off-by: Adam Manzananares <adam.manzanares@wdc.com>
> ---
> block/blk-core.c | 4 +++-
> include/linux/blkdev.h | 14 ++++++++++++++
> 2 files changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/block/blk-core.c b/block/blk-core.c
> index 14d7c07..361b1b9 100644
> --- a/block/blk-core.c
> +++ b/block/blk-core.c
> @@ -1153,6 +1153,7 @@ static struct request *__get_request(struct request_list *rl, int op,
>
> blk_rq_init(q, rq);
> blk_rq_set_rl(rq, rl);
> + blk_rq_set_prio(rq, ioc);
> req_set_op_attrs(rq, op, op_flags | REQ_ALLOCED);
>
> /* init elvpriv */
> @@ -1656,7 +1657,8 @@ void init_request_from_bio(struct request *req, struct bio *bio)
>
> req->errors = 0;
> req->__sector = bio->bi_iter.bi_sector;
> - req->ioprio = bio_prio(bio);
> + if (ioprio_valid(bio_prio(bio)))
> + req->ioprio = bio_prio(bio);
Should we use ioprio_best() here? If req->ioprio and bio_prio()
disagree one side has explicitly asked for a higher priority.
^ permalink raw reply
* [PATCH v4 3/4] ata: Enabling ATA Command Priorities
From: Adam Manzanares @ 2016-10-13 19:53 UTC (permalink / raw)
To: axboe, tj, dan.j.williams, hare, martin.petersen, mchristi,
toshi.kani, ming.lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani
Cc: linux-block, linux-ide, linux-kernel, MPT-FusionLinux.pdl,
linux-scsi, Adam Manzanares, Adam Manzanares
In-Reply-To: <1476388433-2539-1-git-send-email-adam.manzanares@hgst.com>
This patch checks to see if an ATA device supports NCQ command priorities.
If so and the user has specified an iocontext that indicates IO_PRIO_CLASS_RT
then we build a tf with a high priority command.
Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
---
drivers/ata/libata-core.c | 35 ++++++++++++++++++++++++++++++++++-
drivers/ata/libata-scsi.c | 6 +++++-
drivers/ata/libata.h | 2 +-
include/linux/ata.h | 6 ++++++
include/linux/libata.h | 18 ++++++++++++++++++
5 files changed, 64 insertions(+), 3 deletions(-)
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 223a770..181b530 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -739,6 +739,7 @@ u64 ata_tf_read_block(const struct ata_taskfile *tf, struct ata_device *dev)
* @n_block: Number of blocks
* @tf_flags: RW/FUA etc...
* @tag: tag
+ * @class: IO priority class
*
* LOCKING:
* None.
@@ -753,7 +754,7 @@ u64 ata_tf_read_block(const struct ata_taskfile *tf, struct ata_device *dev)
*/
int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
u64 block, u32 n_block, unsigned int tf_flags,
- unsigned int tag)
+ unsigned int tag, int class)
{
tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
tf->flags |= tf_flags;
@@ -785,6 +786,12 @@ int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
tf->device = ATA_LBA;
if (tf->flags & ATA_TFLAG_FUA)
tf->device |= 1 << 7;
+
+ if (ata_ncq_prio_enabled(dev)) {
+ if (class == IOPRIO_CLASS_RT)
+ tf->hob_nsect |= ATA_PRIO_HIGH <<
+ ATA_SHIFT_PRIO;
+ }
} else if (dev->flags & ATA_DFLAG_LBA) {
tf->flags |= ATA_TFLAG_LBA;
@@ -2156,6 +2163,30 @@ static void ata_dev_config_ncq_non_data(struct ata_device *dev)
}
}
+static void ata_dev_config_ncq_prio(struct ata_device *dev)
+{
+ struct ata_port *ap = dev->link->ap;
+ unsigned int err_mask;
+
+ err_mask = ata_read_log_page(dev,
+ ATA_LOG_SATA_ID_DEV_DATA,
+ ATA_LOG_SATA_SETTINGS,
+ ap->sector_buf,
+ 1);
+ if (err_mask) {
+ ata_dev_dbg(dev,
+ "failed to get Identify Device data, Emask 0x%x\n",
+ err_mask);
+ return;
+ }
+
+ if (ap->sector_buf[ATA_LOG_NCQ_PRIO_OFFSET] & BIT(3))
+ dev->flags |= ATA_DFLAG_NCQ_PRIO;
+ else
+ ata_dev_dbg(dev, "SATA page does not support priority\n");
+
+}
+
static int ata_dev_config_ncq(struct ata_device *dev,
char *desc, size_t desc_sz)
{
@@ -2205,6 +2236,8 @@ static int ata_dev_config_ncq(struct ata_device *dev,
ata_dev_config_ncq_send_recv(dev);
if (ata_id_has_ncq_non_data(dev->id))
ata_dev_config_ncq_non_data(dev);
+ if (ata_id_has_ncq_prio(dev->id))
+ ata_dev_config_ncq_prio(dev);
}
return 0;
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index e207b33..18629e8 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -50,6 +50,7 @@
#include <linux/uaccess.h>
#include <linux/suspend.h>
#include <asm/unaligned.h>
+#include <linux/ioprio.h>
#include "libata.h"
#include "libata-transport.h"
@@ -1757,6 +1758,8 @@ static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
{
struct scsi_cmnd *scmd = qc->scsicmd;
const u8 *cdb = scmd->cmnd;
+ struct request *rq = scmd->request;
+ int class = IOPRIO_PRIO_CLASS(req_get_ioprio(rq));
unsigned int tf_flags = 0;
u64 block;
u32 n_block;
@@ -1823,7 +1826,8 @@ static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
qc->nbytes = n_block * scmd->device->sector_size;
rc = ata_build_rw_tf(&qc->tf, qc->dev, block, n_block, tf_flags,
- qc->tag);
+ qc->tag, class);
+
if (likely(rc == 0))
return 0;
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 3b301a4..8f3a559 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -66,7 +66,7 @@ extern u64 ata_tf_to_lba48(const struct ata_taskfile *tf);
extern struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag);
extern int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
u64 block, u32 n_block, unsigned int tf_flags,
- unsigned int tag);
+ unsigned int tag, int class);
extern u64 ata_tf_read_block(const struct ata_taskfile *tf,
struct ata_device *dev);
extern unsigned ata_exec_internal(struct ata_device *dev,
diff --git a/include/linux/ata.h b/include/linux/ata.h
index adbc812..ebe4c3b 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -347,6 +347,7 @@ enum {
ATA_LOG_DEVSLP_DETO = 0x01,
ATA_LOG_DEVSLP_VALID = 0x07,
ATA_LOG_DEVSLP_VALID_MASK = 0x80,
+ ATA_LOG_NCQ_PRIO_OFFSET = 0x09,
/* NCQ send and receive log */
ATA_LOG_NCQ_SEND_RECV_SUBCMDS_OFFSET = 0x00,
@@ -897,6 +898,11 @@ static inline bool ata_id_has_ncq_non_data(const u16 *id)
return id[ATA_ID_SATA_CAPABILITY_2] & BIT(5);
}
+static inline bool ata_id_has_ncq_prio(const u16 *id)
+{
+ return id[ATA_ID_SATA_CAPABILITY] & BIT(12);
+}
+
static inline bool ata_id_has_trim(const u16 *id)
{
if (ata_id_major_version(id) >= 7 &&
diff --git a/include/linux/libata.h b/include/linux/libata.h
index e37d4f9..244f261 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -165,6 +165,7 @@ enum {
ATA_DFLAG_NO_UNLOAD = (1 << 17), /* device doesn't support unload */
ATA_DFLAG_UNLOCK_HPA = (1 << 18), /* unlock HPA */
ATA_DFLAG_NCQ_SEND_RECV = (1 << 19), /* device supports NCQ SEND and RECV */
+ ATA_DFLAG_NCQ_PRIO = (1 << 20), /* device supports NCQ priority */
ATA_DFLAG_INIT_MASK = (1 << 24) - 1,
ATA_DFLAG_DETACH = (1 << 24),
@@ -341,7 +342,9 @@ enum {
ATA_SHIFT_PIO = 0,
ATA_SHIFT_MWDMA = ATA_SHIFT_PIO + ATA_NR_PIO_MODES,
ATA_SHIFT_UDMA = ATA_SHIFT_MWDMA + ATA_NR_MWDMA_MODES,
+ ATA_SHIFT_PRIO = 6,
+ ATA_PRIO_HIGH = 2,
/* size of buffer to pad xfers ending on unaligned boundaries */
ATA_DMA_PAD_SZ = 4,
@@ -1609,6 +1612,21 @@ static inline int ata_ncq_enabled(struct ata_device *dev)
ATA_DFLAG_NCQ)) == ATA_DFLAG_NCQ;
}
+/**
+ * ata_ncq_prio_enabled - Test whether NCQ prio is enabled
+ * @dev: ATA device to test for
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ *
+ * RETURNS:
+ * 1 if NCQ prio is enabled for @dev, 0 otherwise.
+ */
+static inline int ata_ncq_prio_enabled(struct ata_device *dev)
+{
+ return (dev->flags & ATA_DFLAG_NCQ_PRIO) == ATA_DFLAG_NCQ_PRIO;
+}
+
static inline bool ata_fpdma_dsm_supported(struct ata_device *dev)
{
return (dev->flags & ATA_DFLAG_NCQ_SEND_RECV) &&
--
2.1.4
^ permalink raw reply related
* [PATCH v4 4/4] ata: ATA Command Priority Disabled By Default
From: Adam Manzanares @ 2016-10-13 19:53 UTC (permalink / raw)
To: axboe, tj, dan.j.williams, hare, martin.petersen, mchristi,
toshi.kani, ming.lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani
Cc: linux-block, linux-ide, linux-kernel, MPT-FusionLinux.pdl,
linux-scsi, Adam Manzanares, Adam Manzanares
In-Reply-To: <1476388433-2539-1-git-send-email-adam.manzanares@hgst.com>
Add a sysfs entry to turn on priority information being passed
to a ATA device. By default this feature is turned off.
This patch depends on ata: Enabling ATA Command Priorities
Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
---
drivers/ata/libahci.c | 1 +
drivers/ata/libata-core.c | 2 +-
drivers/ata/libata-scsi.c | 68 +++++++++++++++++++++++++++++++++++++++++++++++
include/linux/libata.h | 8 ++++++
4 files changed, 78 insertions(+), 1 deletion(-)
diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index dcf2c72..383adf7 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -140,6 +140,7 @@ EXPORT_SYMBOL_GPL(ahci_shost_attrs);
struct device_attribute *ahci_sdev_attrs[] = {
&dev_attr_sw_activity,
&dev_attr_unload_heads,
+ &dev_attr_enable_prio,
NULL
};
EXPORT_SYMBOL_GPL(ahci_sdev_attrs);
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 181b530..d0cf987 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -787,7 +787,7 @@ int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
if (tf->flags & ATA_TFLAG_FUA)
tf->device |= 1 << 7;
- if (ata_ncq_prio_enabled(dev)) {
+ if (ata_ncq_prio_enabled(dev) && ata_prio_enabled(dev)) {
if (class == IOPRIO_CLASS_RT)
tf->hob_nsect |= ATA_PRIO_HIGH <<
ATA_SHIFT_PRIO;
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 18629e8..10ba118 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -271,6 +271,73 @@ DEVICE_ATTR(unload_heads, S_IRUGO | S_IWUSR,
ata_scsi_park_show, ata_scsi_park_store);
EXPORT_SYMBOL_GPL(dev_attr_unload_heads);
+static ssize_t ata_enable_prio_show(struct device *device,
+ struct device_attribute *attr, char *buf)
+{
+ struct scsi_device *sdev = to_scsi_device(device);
+ struct ata_port *ap;
+ struct ata_device *dev;
+ int rc = 0;
+ int enable_prio;
+
+ ap = ata_shost_to_port(sdev->host);
+
+ spin_lock_irq(ap->lock);
+ dev = ata_scsi_find_dev(ap, sdev);
+ if (!dev) {
+ rc = -ENODEV;
+ goto unlock;
+ }
+
+ enable_prio = ata_prio_enabled(dev);
+
+unlock:
+ spin_unlock_irq(ap->lock);
+
+ return rc ? rc : snprintf(buf, 20, "%u\n", enable_prio);
+}
+
+static ssize_t ata_enable_prio_store(struct device *device,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct scsi_device *sdev = to_scsi_device(device);
+ struct ata_port *ap;
+ struct ata_device *dev;
+ long int input;
+ unsigned long flags;
+ int rc;
+
+ rc = kstrtol(buf, 10, &input);
+ if (rc)
+ return rc;
+ if ((input < 0) || (input > 1))
+ return -EINVAL;
+
+ ap = ata_shost_to_port(sdev->host);
+
+ spin_lock_irqsave(ap->lock, flags);
+ dev = ata_scsi_find_dev(ap, sdev);
+ if (unlikely(!dev)) {
+ rc = -ENODEV;
+ goto unlock;
+ }
+
+ if (input)
+ dev->flags |= ATA_DFLAG_ENABLE_PRIO;
+ else
+ dev->flags &= ~ATA_DFLAG_ENABLE_PRIO;
+
+unlock:
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ return rc ? rc : len;
+}
+
+DEVICE_ATTR(enable_prio, S_IRUGO | S_IWUSR,
+ ata_enable_prio_show, ata_enable_prio_store);
+EXPORT_SYMBOL_GPL(dev_attr_enable_prio);
+
void ata_scsi_set_sense(struct ata_device *dev, struct scsi_cmnd *cmd,
u8 sk, u8 asc, u8 ascq)
{
@@ -402,6 +469,7 @@ EXPORT_SYMBOL_GPL(dev_attr_sw_activity);
struct device_attribute *ata_common_sdev_attrs[] = {
&dev_attr_unload_heads,
+ &dev_attr_enable_prio,
NULL
};
EXPORT_SYMBOL_GPL(ata_common_sdev_attrs);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 244f261..c8acb16 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -166,6 +166,7 @@ enum {
ATA_DFLAG_UNLOCK_HPA = (1 << 18), /* unlock HPA */
ATA_DFLAG_NCQ_SEND_RECV = (1 << 19), /* device supports NCQ SEND and RECV */
ATA_DFLAG_NCQ_PRIO = (1 << 20), /* device supports NCQ priority */
+ ATA_DFLAG_ENABLE_PRIO = (1 << 21), /* User enable device priority */
ATA_DFLAG_INIT_MASK = (1 << 24) - 1,
ATA_DFLAG_DETACH = (1 << 24),
@@ -544,6 +545,7 @@ typedef void (*ata_postreset_fn_t)(struct ata_link *link, unsigned int *classes)
extern struct device_attribute dev_attr_link_power_management_policy;
extern struct device_attribute dev_attr_unload_heads;
+extern struct device_attribute dev_attr_enable_prio;
extern struct device_attribute dev_attr_em_message_type;
extern struct device_attribute dev_attr_em_message;
extern struct device_attribute dev_attr_sw_activity;
@@ -1627,6 +1629,12 @@ static inline int ata_ncq_prio_enabled(struct ata_device *dev)
return (dev->flags & ATA_DFLAG_NCQ_PRIO) == ATA_DFLAG_NCQ_PRIO;
}
+static inline int ata_prio_enabled(struct ata_device *dev)
+{
+ return ((dev->flags & ATA_DFLAG_ENABLE_PRIO) ==
+ ATA_DFLAG_ENABLE_PRIO);
+}
+
static inline bool ata_fpdma_dsm_supported(struct ata_device *dev)
{
return (dev->flags & ATA_DFLAG_NCQ_SEND_RECV) &&
--
2.1.4
^ permalink raw reply related
* [PATCH v4 2/4] fusion: remove iopriority handling
From: Adam Manzanares @ 2016-10-13 19:53 UTC (permalink / raw)
To: axboe, tj, dan.j.williams, hare, martin.petersen, mchristi,
toshi.kani, ming.lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani
Cc: linux-block, linux-ide, linux-kernel, MPT-FusionLinux.pdl,
linux-scsi, Adam Manzanares, Adam Manzanares
In-Reply-To: <1476388433-2539-1-git-send-email-adam.manzanares@hgst.com>
The request priority is now by default coming from the ioc. It was not
clear what this code was trying to do based upon the iopriority class or
data. The driver should check that a device supports priorities and use
them according to the specificiations of ioprio.
Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
---
drivers/message/fusion/mptscsih.c | 5 -----
1 file changed, 5 deletions(-)
diff --git a/drivers/message/fusion/mptscsih.c b/drivers/message/fusion/mptscsih.c
index 6c9fc11..4740bb6 100644
--- a/drivers/message/fusion/mptscsih.c
+++ b/drivers/message/fusion/mptscsih.c
@@ -1369,11 +1369,6 @@ mptscsih_qcmd(struct scsi_cmnd *SCpnt)
if ((vdevice->vtarget->tflags & MPT_TARGET_FLAGS_Q_YES)
&& (SCpnt->device->tagged_supported)) {
scsictl = scsidir | MPI_SCSIIO_CONTROL_SIMPLEQ;
- if (SCpnt->request && SCpnt->request->ioprio) {
- if (((SCpnt->request->ioprio & 0x7) == 1) ||
- !(SCpnt->request->ioprio & 0x7))
- scsictl |= MPI_SCSIIO_CONTROL_HEADOFQ;
- }
} else
scsictl = scsidir | MPI_SCSIIO_CONTROL_UNTAGGED;
--
2.1.4
^ permalink raw reply related
* [PATCH v4 1/4] block: Add iocontext priority to request
From: Adam Manzanares @ 2016-10-13 19:53 UTC (permalink / raw)
To: axboe, tj, dan.j.williams, hare, martin.petersen, mchristi,
toshi.kani, ming.lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani
Cc: linux-block, linux-ide, linux-kernel, MPT-FusionLinux.pdl,
linux-scsi, Adam Manzanares, Adam Manzananares
In-Reply-To: <1476388433-2539-1-git-send-email-adam.manzanares@hgst.com>
Patch adds an association between iocontext ioprio and the ioprio of a
request. This value is set in blk_rq_set_prio which takes the request and
the ioc as arguments. If the ioc is valid in blk_rq_set_prio then the
iopriority of the request is set as the iopriority of the ioc. In
init_request_from_bio a check is made to see if the ioprio of the bio is
valid and if so then the request prio comes from the bio.
Signed-off-by: Adam Manzananares <adam.manzanares@wdc.com>
---
block/blk-core.c | 4 +++-
include/linux/blkdev.h | 14 ++++++++++++++
2 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index 14d7c07..361b1b9 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1153,6 +1153,7 @@ static struct request *__get_request(struct request_list *rl, int op,
blk_rq_init(q, rq);
blk_rq_set_rl(rq, rl);
+ blk_rq_set_prio(rq, ioc);
req_set_op_attrs(rq, op, op_flags | REQ_ALLOCED);
/* init elvpriv */
@@ -1656,7 +1657,8 @@ void init_request_from_bio(struct request *req, struct bio *bio)
req->errors = 0;
req->__sector = bio->bi_iter.bi_sector;
- req->ioprio = bio_prio(bio);
+ if (ioprio_valid(bio_prio(bio)))
+ req->ioprio = bio_prio(bio);
blk_rq_bio_prep(req->q, req, bio);
}
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index c47c358..9a0ceaa 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -934,6 +934,20 @@ static inline unsigned int blk_rq_count_bios(struct request *rq)
}
/*
+ * blk_rq_set_prio - associate a request with prio from ioc
+ * @rq: request of interest
+ * @ioc: target iocontext
+ *
+ * Assocate request prio with ioc prio so request based drivers
+ * can leverage priority information.
+ */
+static inline void blk_rq_set_prio(struct request *rq, struct io_context *ioc)
+{
+ if (ioc)
+ rq->ioprio = ioc->ioprio;
+}
+
+/*
* Request issue related functions.
*/
extern struct request *blk_peek_request(struct request_queue *q);
--
2.1.4
^ permalink raw reply related
* [PATCH v4 0/4] Enabling ATA Command Priorities
From: Adam Manzanares @ 2016-10-13 19:53 UTC (permalink / raw)
To: axboe, tj, dan.j.williams, hare, martin.petersen, mchristi,
toshi.kani, ming.lei, sathya.prakash, chaitra.basappa,
suganath-prabu.subramani
Cc: linux-block, linux-ide, linux-kernel, MPT-FusionLinux.pdl,
linux-scsi, Adam Manzanares
This patch builds ATA commands with high priority if the iocontext
of a process is set to real time. The goal of the patch is to
improve tail latencies of workloads that use higher queue depths.
This required setting the iocontext ioprio on the request when
the request is initialized.
This patch has been tested with an Ultrastar HE8 HDD and cuts the
the p99.99 tail latency of foreground IO from 2s down to 72ms when
using the deadline scheduler. This patch works independently of the
scheduler so it can be used with all of the currently available
request based schedulers.
Foreground IO, for the previously described results, is an async fio job
submitting 4K read requests at a QD of 1 to the HDD. The foreground IO is set
with the iopriority class of real time. The background workload is another fio
job submitting read requests at a QD of 32 to the same HDD with default
iopriority.
This feature is enabled for ATA devices by setting the ata enable_prio device
attribute to 1. An ATA device is also checked to see if the device supports per
command priority.
v4:
- Added blk_rq_set_prio function to associate request prio with ioc prio
- In init_request_from_bio use bio_prio if it is valid
- Added ata enable_prio dev attribute to sysfs to enable prioritized commands
v3:
- Removed null dereference issue in blk-core
- Renamed queue sysfs entries for clarity
- Added documentation for sysfs queue entry
v2:
- Add queue flag to set iopriority going to the request
- If queue flag set, send iopriority class to ata_build_rw_tf
- Remove redundant code in ata_ncq_prio_enabled function.
Adam Manzanares (4):
block: Add iocontext priority to request
fusion: remove iopriority handling
ata: Enabling ATA Command Priorities
ata: ATA Command Priority Disabled By Default
block/blk-core.c | 4 ++-
drivers/ata/libahci.c | 1 +
drivers/ata/libata-core.c | 35 +++++++++++++++++-
drivers/ata/libata-scsi.c | 74 ++++++++++++++++++++++++++++++++++++++-
drivers/ata/libata.h | 2 +-
drivers/message/fusion/mptscsih.c | 5 ---
include/linux/ata.h | 6 ++++
include/linux/blkdev.h | 14 ++++++++
include/linux/libata.h | 26 ++++++++++++++
9 files changed, 158 insertions(+), 9 deletions(-)
--
2.1.4
^ permalink raw reply
* Re: [PATCH v3 1/2] block: Add iocontext priority to request
From: Jens Axboe @ 2016-10-12 21:05 UTC (permalink / raw)
To: Adam Manzanares; +Cc: Adam Manzanares, tj, linux-block, linux-ide
In-Reply-To: <20161012175830.GA4072@hgst.com>
On 10/12/2016 11:58 AM, Adam Manzanares wrote:
> The 10/12/2016 08:49, Jens Axboe wrote:
>> On 10/11/2016 02:40 PM, Adam Manzanares wrote:
>>> Patch adds an association between iocontext ioprio and the ioprio of
>>> a request. This feature is only enabled if a queue flag is set to
>>> indicate that requests should have ioprio associated with them. The
>>> queue flag is exposed as the req_prio queue sysfs entry.
>>
>> Honestly, I don't get this patchset. For the normal file system path, we
>> inherit the iocontext priority into the bio. That in turns gets
>> inherited by the request. Why is this any different?
>>
> I was hoping this was true before I started looking into this, but the
> iocontext priority is not set on the bio. I did look into setting the
> iocontext priority on the bio, and this would have do be done close
> in the call stack to init_request_from_bio so I chose to set it here.
>
> If I missed where this occurs I would appreciate it if you pointed me
> to the code where the bio gets the iopriority from the iocontext.
It currently happens in CFQ, since that is what deals with priorities.
But we should just make that the case, generically. The rule is that if
priority is set in a bio, that is what we'll use. But if not, we'll
use what the application has set in general, and that is available in
the io context.
>> It'd be much cleaner to just have 'rq' inherit the IO priority from the
>> io context when the 'rq' is allocated, and ensuring that we inherit and
>> override this if the bio has one set instead. It should already work
>> like that.
>
> I looked into the request allocation code and the only place I see where
> the iocontext is associated with the request is through a icq. Looking at
> the documentation of the icq it states that the icq_size of the elevator
> has to be set in order for block core to manage this. The only scheduler
> using this currently is the cfq scheduler and I think prioritized requests
> should be independent of the scheduler used.
Agree, see above, it should just happen generically.
>> And in no way should we add some sysfs file to control this, that is
>> nuts.
>
> My concern is that we will now be exposing priority information to lower
> layers and if there happens to be code that uses the priority now it will
> actually make an impact. My example being the fusion mptsas driver.
>
> The second issue I foresee is that lower level drivers will need a sysfs
> file to control whether or not we send prioritized commands to the device.
> We are wary of sending prioritized commands by default when we are unsure
> of how the device will respond to these prioritized commands.
>
> The reason I propose a sysfs file in the queue is that it solves these two
> issues at the same time.
>
> I would appreciate it if you could suggest an alternative fix for
> these issues or an explanation of why these concerns are not valid.
At that point it should be a driver knob, it's not something that should
be part of the generic block layer.
--
Jens Axboe
^ permalink raw reply
* Re: [PATCH v3 1/2] block: Add iocontext priority to request
From: Adam Manzanares @ 2016-10-12 17:58 UTC (permalink / raw)
To: Jens Axboe; +Cc: Adam Manzanares, tj, linux-block, linux-ide
In-Reply-To: <4b60fe5d-113f-9361-bbae-7473002500ba@kernel.dk>
The 10/12/2016 08:49, Jens Axboe wrote:
> On 10/11/2016 02:40 PM, Adam Manzanares wrote:
> >Patch adds an association between iocontext ioprio and the ioprio of
> >a request. This feature is only enabled if a queue flag is set to
> >indicate that requests should have ioprio associated with them. The
> >queue flag is exposed as the req_prio queue sysfs entry.
>
> Honestly, I don't get this patchset. For the normal file system path, we
> inherit the iocontext priority into the bio. That in turns gets
> inherited by the request. Why is this any different?
>
I was hoping this was true before I started looking into this, but the
iocontext priority is not set on the bio. I did look into setting the
iocontext priority on the bio, and this would have do be done close
in the call stack to init_request_from_bio so I chose to set it here.
If I missed where this occurs I would appreciate it if you pointed me to the
code where the bio gets the iopriority from the iocontext.
> It'd be much cleaner to just have 'rq' inherit the IO priority from the
> io context when the 'rq' is allocated, and ensuring that we inherit and
> override this if the bio has one set instead. It should already work
> like that.
I looked into the request allocation code and the only place I see where
the iocontext is associated with the request is through a icq. Looking at
the documentation of the icq it states that the icq_size of the elevator
has to be set in order for block core to manage this. The only scheduler
using this currently is the cfq scheduler and I think prioritized requests
should be independent of the scheduler used.
I agree that this should make it into the code where the rq is allocated.
Again if I have missed something please point me to the relevant code and
I will modify the patch as necessary.
>
> And in no way should we add some sysfs file to control this, that is
> nuts.
My concern is that we will now be exposing priority information to lower
layers and if there happens to be code that uses the priority now it will
actually make an impact. My example being the fusion mptsas driver.
The second issue I foresee is that lower level drivers will need a sysfs
file to control whether or not we send prioritized commands to the device.
We are wary of sending prioritized commands by default when we are unsure
of how the device will respond to these prioritized commands.
The reason I propose a sysfs file in the queue is that it solves these two
issues at the same time.
I would appreciate it if you could suggest an alternative fix for these issues
or an explanation of why these concerns are not valid.
>
> --
> Jens Axboe
>
Take care,
Adam
^ permalink raw reply
* Re: [PATCH v3 1/2] block: Add iocontext priority to request
From: Jens Axboe @ 2016-10-12 14:49 UTC (permalink / raw)
To: Adam Manzanares, tj; +Cc: linux-block, linux-ide
In-Reply-To: <1476218427-4021-2-git-send-email-adam.manzanares@hgst.com>
On 10/11/2016 02:40 PM, Adam Manzanares wrote:
> Patch adds an association between iocontext ioprio and the ioprio of
> a request. This feature is only enabled if a queue flag is set to
> indicate that requests should have ioprio associated with them. The
> queue flag is exposed as the req_prio queue sysfs entry.
Honestly, I don't get this patchset. For the normal file system path, we
inherit the iocontext priority into the bio. That in turns gets
inherited by the request. Why is this any different?
It'd be much cleaner to just have 'rq' inherit the IO priority from the
io context when the 'rq' is allocated, and ensuring that we inherit and
override this if the bio has one set instead. It should already work
like that.
And in no way should we add some sysfs file to control this, that is
nuts.
--
Jens Axboe
^ permalink raw reply
* [PATCH] Fix interface autodetection in legacy IDE driver (trial #2)
From: Luiz Carlos Ramos @ 2016-10-12 1:12 UTC (permalink / raw)
To: linux-ide@vger.kernel.org
Hello,
This humble patch was sent one or two months before, and had no actions,
except for a colleague reply which friendly pointed out some formatting
problems (which were solved in a second message).
It relates to an old code, the legacy IDE driver, but the bug it
addresses is real. The code, although rarely used, is
still there to be compiled if one chooses to do so (like me).
Also, the fix has a very low risk of present collateral effects IMHO.
It is already compiled and tested in some embedded machines.
So, again IMHO, it is worth be fixed.
This email is a second trial with it. I hope it can help the one or two
guys out there which are still running the legacy IDE driver and
haven't noticed the former email.
Best regards,
Signed-off-by: Luiz Carlos Ramos <lramos.prof@yahoo.com.br>
---
drivers/ide/ide-generic.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/ide/ide-generic.c b/drivers/ide/ide-generic.c
index 54d7c4685d23aa5e62ce606e7b994a57bb54b08a..419818a39c270d3ad219e8f7b5df56a9aea3d640 100644
--- a/drivers/ide/ide-generic.c
+++ b/drivers/ide/ide-generic.c
@@ -96,10 +96,10 @@ static int __init ide_generic_init(void)
printk(KERN_INFO DRV_NAME ": please use \"probe_mask=0x3f\" "
"module parameter for probing all legacy ISA IDE ports\n");
- if (primary == 0)
+ if (primary)
probe_mask |= 0x1;
- if (secondary == 0)
+ if (secondary)
probe_mask |= 0x2;
} else
printk(KERN_INFO DRV_NAME ": enforcing probing of I/O ports "
--
2.8.2
^ permalink raw reply related
* [PATCH v3 0/2] Enabling ATA Command Priorities
From: Adam Manzanares @ 2016-10-11 20:40 UTC (permalink / raw)
To: axboe, tj; +Cc: linux-block, linux-ide, Adam Manzanares
This patch builds ATA commands with high priority if the iocontext
of a process is set to real time. The goal of the patch is to
improve tail latencies of workloads that use higher queue depths.
This patch has been tested with an Ultrastar HE8 HDD and cuts the
the p99.99 tail latency of foreground IO from 2s down to 72ms when
using the deadline scheduler. This patch works independently of the
scheduler so it can be used with all of the currently available
request based schedulers.
Foreground IO, for the previously described results, is an async fio job
submitting 4K read requests at a QD of 1 to the HDD. The foreground IO is set
with the iopriority class of real time. The background workload is another fio
job submitting read requests at a QD of 32 to the same HDD with default
iopriority.
This feature is enabled by setting a queue flag that is exposed as a sysfs
entry named rq_ioc_prio. If this feature is enabled, and the submission
iocontext exists, and the bio_prio is not valid then the request ioprio is
set to the iocontext prio.
v3:
- Removed null dereference issue in blk-core
- Renamed queue sysfs entries for clarity
- Added documentation for sysfs queue entry
v2:
- Add queue flag to set iopriority going to the request
- If queue flag set, send iopriority class to ata_build_rw_tf
- Remove redundant code in ata_ncq_prio_enabled function.
Adam Manzanares (2):
block: Add iocontext priority to request
ata: Enabling ATA Command Priorities
Documentation/block/queue-sysfs.txt | 12 ++++++++++++
block/blk-core.c | 5 +++++
block/blk-sysfs.c | 32 ++++++++++++++++++++++++++++++++
drivers/ata/libata-core.c | 35 ++++++++++++++++++++++++++++++++++-
drivers/ata/libata-scsi.c | 10 +++++++++-
drivers/ata/libata.h | 2 +-
include/linux/ata.h | 6 ++++++
include/linux/blkdev.h | 3 +++
include/linux/libata.h | 18 ++++++++++++++++++
9 files changed, 120 insertions(+), 3 deletions(-)
--
2.1.4
^ permalink raw reply
* [PATCH v3 2/2] ata: Enabling ATA Command Priorities
From: Adam Manzanares @ 2016-10-11 20:40 UTC (permalink / raw)
To: axboe, tj; +Cc: linux-block, linux-ide, Adam Manzanares
In-Reply-To: <1476218427-4021-1-git-send-email-adam.manzanares@hgst.com>
This patch checks to see if an ATA device supports NCQ command priorities.
If so and the user has specified an iocontext that indicates IO_PRIO_CLASS_RT
and also enables request priorities in the block queue then we build a tf
with a high priority command.
This patch depends on patch block-Add-iocontext-priority-to-request
Signed-off-by: Adam Manzanares <adam.manzanares@hgst.com>
---
drivers/ata/libata-core.c | 35 ++++++++++++++++++++++++++++++++++-
drivers/ata/libata-scsi.c | 10 +++++++++-
drivers/ata/libata.h | 2 +-
include/linux/ata.h | 6 ++++++
include/linux/libata.h | 18 ++++++++++++++++++
5 files changed, 68 insertions(+), 3 deletions(-)
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 223a770..181b530 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -739,6 +739,7 @@ u64 ata_tf_read_block(const struct ata_taskfile *tf, struct ata_device *dev)
* @n_block: Number of blocks
* @tf_flags: RW/FUA etc...
* @tag: tag
+ * @class: IO priority class
*
* LOCKING:
* None.
@@ -753,7 +754,7 @@ u64 ata_tf_read_block(const struct ata_taskfile *tf, struct ata_device *dev)
*/
int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
u64 block, u32 n_block, unsigned int tf_flags,
- unsigned int tag)
+ unsigned int tag, int class)
{
tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
tf->flags |= tf_flags;
@@ -785,6 +786,12 @@ int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
tf->device = ATA_LBA;
if (tf->flags & ATA_TFLAG_FUA)
tf->device |= 1 << 7;
+
+ if (ata_ncq_prio_enabled(dev)) {
+ if (class == IOPRIO_CLASS_RT)
+ tf->hob_nsect |= ATA_PRIO_HIGH <<
+ ATA_SHIFT_PRIO;
+ }
} else if (dev->flags & ATA_DFLAG_LBA) {
tf->flags |= ATA_TFLAG_LBA;
@@ -2156,6 +2163,30 @@ static void ata_dev_config_ncq_non_data(struct ata_device *dev)
}
}
+static void ata_dev_config_ncq_prio(struct ata_device *dev)
+{
+ struct ata_port *ap = dev->link->ap;
+ unsigned int err_mask;
+
+ err_mask = ata_read_log_page(dev,
+ ATA_LOG_SATA_ID_DEV_DATA,
+ ATA_LOG_SATA_SETTINGS,
+ ap->sector_buf,
+ 1);
+ if (err_mask) {
+ ata_dev_dbg(dev,
+ "failed to get Identify Device data, Emask 0x%x\n",
+ err_mask);
+ return;
+ }
+
+ if (ap->sector_buf[ATA_LOG_NCQ_PRIO_OFFSET] & BIT(3))
+ dev->flags |= ATA_DFLAG_NCQ_PRIO;
+ else
+ ata_dev_dbg(dev, "SATA page does not support priority\n");
+
+}
+
static int ata_dev_config_ncq(struct ata_device *dev,
char *desc, size_t desc_sz)
{
@@ -2205,6 +2236,8 @@ static int ata_dev_config_ncq(struct ata_device *dev,
ata_dev_config_ncq_send_recv(dev);
if (ata_id_has_ncq_non_data(dev->id))
ata_dev_config_ncq_non_data(dev);
+ if (ata_id_has_ncq_prio(dev->id))
+ ata_dev_config_ncq_prio(dev);
}
return 0;
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index e207b33..4304694 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -50,6 +50,7 @@
#include <linux/uaccess.h>
#include <linux/suspend.h>
#include <asm/unaligned.h>
+#include <linux/ioprio.h>
#include "libata.h"
#include "libata-transport.h"
@@ -1757,6 +1758,8 @@ static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
{
struct scsi_cmnd *scmd = qc->scsicmd;
const u8 *cdb = scmd->cmnd;
+ struct request *rq = scmd->request;
+ int class = 0;
unsigned int tf_flags = 0;
u64 block;
u32 n_block;
@@ -1822,8 +1825,13 @@ static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc)
qc->flags |= ATA_QCFLAG_IO;
qc->nbytes = n_block * scmd->device->sector_size;
+ /* If queue supports req prio pass it onto the task file */
+ if (blk_queue_rq_ioc_prio(rq->q))
+ class = IOPRIO_PRIO_CLASS(req_get_ioprio(rq));
+
rc = ata_build_rw_tf(&qc->tf, qc->dev, block, n_block, tf_flags,
- qc->tag);
+ qc->tag, class);
+
if (likely(rc == 0))
return 0;
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index 3b301a4..8f3a559 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -66,7 +66,7 @@ extern u64 ata_tf_to_lba48(const struct ata_taskfile *tf);
extern struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag);
extern int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
u64 block, u32 n_block, unsigned int tf_flags,
- unsigned int tag);
+ unsigned int tag, int class);
extern u64 ata_tf_read_block(const struct ata_taskfile *tf,
struct ata_device *dev);
extern unsigned ata_exec_internal(struct ata_device *dev,
diff --git a/include/linux/ata.h b/include/linux/ata.h
index adbc812..ebe4c3b 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -347,6 +347,7 @@ enum {
ATA_LOG_DEVSLP_DETO = 0x01,
ATA_LOG_DEVSLP_VALID = 0x07,
ATA_LOG_DEVSLP_VALID_MASK = 0x80,
+ ATA_LOG_NCQ_PRIO_OFFSET = 0x09,
/* NCQ send and receive log */
ATA_LOG_NCQ_SEND_RECV_SUBCMDS_OFFSET = 0x00,
@@ -897,6 +898,11 @@ static inline bool ata_id_has_ncq_non_data(const u16 *id)
return id[ATA_ID_SATA_CAPABILITY_2] & BIT(5);
}
+static inline bool ata_id_has_ncq_prio(const u16 *id)
+{
+ return id[ATA_ID_SATA_CAPABILITY] & BIT(12);
+}
+
static inline bool ata_id_has_trim(const u16 *id)
{
if (ata_id_major_version(id) >= 7 &&
diff --git a/include/linux/libata.h b/include/linux/libata.h
index e37d4f9..244f261 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -165,6 +165,7 @@ enum {
ATA_DFLAG_NO_UNLOAD = (1 << 17), /* device doesn't support unload */
ATA_DFLAG_UNLOCK_HPA = (1 << 18), /* unlock HPA */
ATA_DFLAG_NCQ_SEND_RECV = (1 << 19), /* device supports NCQ SEND and RECV */
+ ATA_DFLAG_NCQ_PRIO = (1 << 20), /* device supports NCQ priority */
ATA_DFLAG_INIT_MASK = (1 << 24) - 1,
ATA_DFLAG_DETACH = (1 << 24),
@@ -341,7 +342,9 @@ enum {
ATA_SHIFT_PIO = 0,
ATA_SHIFT_MWDMA = ATA_SHIFT_PIO + ATA_NR_PIO_MODES,
ATA_SHIFT_UDMA = ATA_SHIFT_MWDMA + ATA_NR_MWDMA_MODES,
+ ATA_SHIFT_PRIO = 6,
+ ATA_PRIO_HIGH = 2,
/* size of buffer to pad xfers ending on unaligned boundaries */
ATA_DMA_PAD_SZ = 4,
@@ -1609,6 +1612,21 @@ static inline int ata_ncq_enabled(struct ata_device *dev)
ATA_DFLAG_NCQ)) == ATA_DFLAG_NCQ;
}
+/**
+ * ata_ncq_prio_enabled - Test whether NCQ prio is enabled
+ * @dev: ATA device to test for
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ *
+ * RETURNS:
+ * 1 if NCQ prio is enabled for @dev, 0 otherwise.
+ */
+static inline int ata_ncq_prio_enabled(struct ata_device *dev)
+{
+ return (dev->flags & ATA_DFLAG_NCQ_PRIO) == ATA_DFLAG_NCQ_PRIO;
+}
+
static inline bool ata_fpdma_dsm_supported(struct ata_device *dev)
{
return (dev->flags & ATA_DFLAG_NCQ_SEND_RECV) &&
--
2.1.4
^ permalink raw reply related
* [PATCH v3 1/2] block: Add iocontext priority to request
From: Adam Manzanares @ 2016-10-11 20:40 UTC (permalink / raw)
To: axboe, tj; +Cc: linux-block, linux-ide, Adam Manzanares
In-Reply-To: <1476218427-4021-1-git-send-email-adam.manzanares@hgst.com>
Patch adds an association between iocontext ioprio and the ioprio of
a request. This feature is only enabled if a queue flag is set to
indicate that requests should have ioprio associated with them. The
queue flag is exposed as the req_prio queue sysfs entry.
Signed-off-by: Adam Mananzanares <adam.manzanares@hgst.com>
---
Documentation/block/queue-sysfs.txt | 12 ++++++++++++
block/blk-core.c | 5 +++++
block/blk-sysfs.c | 32 ++++++++++++++++++++++++++++++++
include/linux/blkdev.h | 3 +++
4 files changed, 52 insertions(+)
diff --git a/Documentation/block/queue-sysfs.txt b/Documentation/block/queue-sysfs.txt
index 2a39040..3ca4e8f 100644
--- a/Documentation/block/queue-sysfs.txt
+++ b/Documentation/block/queue-sysfs.txt
@@ -144,6 +144,18 @@ For storage configurations that need to maximize distribution of completion
processing setting this option to '2' forces the completion to run on the
requesting cpu (bypassing the "group" aggregation logic).
+rq_ioc_prio (RW)
+----------------
+If this option is '1', and there is a valid iocontext associated with the
+issuing context, and the bio we are processing does not have a valid
+prio, then we save the prio value from the iocontext with the request.
+
+This feature can be combined with device drivers that are aware of prio
+values in order to handle prio accordingly. An example would be if the ata
+layer recognizes prio and creates ata commands with high priority and sends
+them to the device. If the hardware supports priorities for commands then
+this has the potential to speed up response times for high priority IO.
+
scheduler (RW)
--------------
When read, this file will display the current and available IO schedulers
diff --git a/block/blk-core.c b/block/blk-core.c
index 14d7c07..2e740c4 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -33,6 +33,7 @@
#include <linux/ratelimit.h>
#include <linux/pm_runtime.h>
#include <linux/blk-cgroup.h>
+#include <linux/ioprio.h>
#define CREATE_TRACE_POINTS
#include <trace/events/block.h>
@@ -1648,6 +1649,7 @@ unsigned int blk_plug_queued_count(struct request_queue *q)
void init_request_from_bio(struct request *req, struct bio *bio)
{
+ struct io_context *ioc = rq_ioc(bio);
req->cmd_type = REQ_TYPE_FS;
req->cmd_flags |= bio->bi_opf & REQ_COMMON_MASK;
@@ -1657,6 +1659,9 @@ void init_request_from_bio(struct request *req, struct bio *bio)
req->errors = 0;
req->__sector = bio->bi_iter.bi_sector;
req->ioprio = bio_prio(bio);
+ if (blk_queue_rq_ioc_prio(req->q) && !ioprio_valid(req->ioprio) && ioc)
+ req->ioprio = ioc->ioprio;
+
blk_rq_bio_prep(req->q, req, bio);
}
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 9cc8d7c..a9c5105 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -384,6 +384,31 @@ static ssize_t queue_dax_show(struct request_queue *q, char *page)
return queue_var_show(blk_queue_dax(q), page);
}
+static ssize_t queue_rq_ioc_prio_show(struct request_queue *q, char *page)
+{
+ return queue_var_show(blk_queue_rq_ioc_prio(q), page);
+}
+
+static ssize_t queue_rq_ioc_prio_store(struct request_queue *q,
+ const char *page, size_t count)
+{
+ unsigned long rq_ioc_prio_on;
+ ssize_t ret;
+
+ ret = queue_var_store(&rq_ioc_prio_on, page, count);
+ if (ret < 0)
+ return ret;
+
+ spin_lock_irq(q->queue_lock);
+ if (rq_ioc_prio_on)
+ queue_flag_set(QUEUE_FLAG_RQ_IOC_PRIO, q);
+ else
+ queue_flag_clear(QUEUE_FLAG_RQ_IOC_PRIO, q);
+ spin_unlock_irq(q->queue_lock);
+
+ return ret;
+}
+
static struct queue_sysfs_entry queue_requests_entry = {
.attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR },
.show = queue_requests_show,
@@ -526,6 +551,12 @@ static struct queue_sysfs_entry queue_dax_entry = {
.show = queue_dax_show,
};
+static struct queue_sysfs_entry queue_rq_ioc_prio_entry = {
+ .attr = {.name = "rq_ioc_prio", .mode = S_IRUGO | S_IWUSR },
+ .show = queue_rq_ioc_prio_show,
+ .store = queue_rq_ioc_prio_store,
+};
+
static struct attribute *default_attrs[] = {
&queue_requests_entry.attr,
&queue_ra_entry.attr,
@@ -553,6 +584,7 @@ static struct attribute *default_attrs[] = {
&queue_poll_entry.attr,
&queue_wc_entry.attr,
&queue_dax_entry.attr,
+ &queue_rq_ioc_prio_entry.attr,
NULL,
};
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index c47c358..63b842a 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -505,6 +505,7 @@ struct request_queue {
#define QUEUE_FLAG_FUA 24 /* device supports FUA writes */
#define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */
#define QUEUE_FLAG_DAX 26 /* device supports DAX */
+#define QUEUE_FLAG_RQ_IOC_PRIO 27 /* Use iocontext ioprio */
#define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
(1 << QUEUE_FLAG_STACKABLE) | \
@@ -595,6 +596,8 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
#define blk_queue_secure_erase(q) \
(test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
#define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
+#define blk_queue_rq_ioc_prio(q) \
+ test_bit(QUEUE_FLAG_RQ_IOC_PRIO, &(q)->queue_flags)
#define blk_noretry_request(rq) \
((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
--
2.1.4
^ permalink raw reply related
* Re: [PATCH v2 2/2] block: Add iocontext priority to request
From: Adam Manzanares @ 2016-10-10 20:37 UTC (permalink / raw)
To: Jeff Moyer; +Cc: axboe, tj, linux-block, linux-ide
In-Reply-To: <x49d1jdi7lz.fsf@segfault.boston.devel.redhat.com>
Hello Jeff,
The 10/06/2016 15:46, Jeff Moyer wrote:
> Hi, Adam,
>
> Adam Manzanares <adam.manzanares@hgst.com> writes:
>
> > Patch adds an association between iocontext ioprio and the ioprio of
> > a request. This feature is only enabled if a queue flag is set to
> > indicate that requests should have ioprio associated with them. The
> > queue flag is exposed as the req_prio queue sysfs entry.
> >
> > Signed-off-by: Adam Mananzanares <adam.manzanares@hgst.com>
>
> I like the idea of the patch, but I have a few comments.
>
> First, don't add a tunable, there's no need for it. (And in the future,
> if you do add tunables, document them.) That should make your patch
> much smaller.
>
I have a strong preference for making this a tunable for the following
reason. I am concerned that this could negatively impact performance if this
feature is not properly implemented on a device. In addition, this feature
can make a dramatic difference in the performance of prioritized vs
non-prioritized IO. Priority IO is improved, but it comes at the cost of
non-prioritized IO. If someone has tuned a system in such a way that things
work well as is, I do not want to cause any surprises.
I can see the argument for not having the tunable in the block layer, but
then we need to add a tunable to all request based drivers that may leverage
the iopriority information. This has the potential to generate a lot more
code and documentation. I also would like to use the tunable when the
iopriority is set on the request so we can preserve the default behavior.
This can be a concern when we have drivers that use request iopriority
information, such as the fusion mptsas driver.
I will also document the tunable :) if we agree that it is necessary.
> > @@ -1648,6 +1649,7 @@ out:
> >
> > void init_request_from_bio(struct request *req, struct bio *bio)
> > {
> > + struct io_context *ioc = rq_ioc(bio);
>
> That can return NULL, and you blindly dereference it later.
>
Ouch, this will be cleaned up in the next revision.
> > @@ -1656,7 +1658,11 @@ void init_request_from_bio(struct request *req, struct bio *bio)
> >
> > req->errors = 0;
> > req->__sector = bio->bi_iter.bi_sector;
> > - req->ioprio = bio_prio(bio);
> > + if (blk_queue_req_prio(req->q))
> > + req->ioprio = ioprio_best(bio_prio(bio), ioc->ioprio);
> > + else
> > + req->ioprio = bio_prio(bio);
> > +
>
> If the bio actually has an ioprio (only happens for bcache at this
> point), you should use it. Something like this:
>
> req->ioprio = bio_prio(bio);
> if (!req->ioprio && ioc)
> req->ioprio = ioc->ioprio;
>
I caught this in the explanation of the first patch I sent out. I am still
assuming that this will be a tunable, but I will have the bio_prio take
precedence in the next patch.
> Finally, please re-order your series as Hannes suggested.
Will do.
>
> Thanks!
> Jeff
Take care,
Adam
^ permalink raw reply
* [Bug 176931] ata failed to IDENTIFY, suspected regression
From: bugzilla-daemon @ 2016-10-10 13:04 UTC (permalink / raw)
To: linux-ide
In-Reply-To: <bug-176931-11633@https.bugzilla.kernel.org/>
https://bugzilla.kernel.org/show_bug.cgi?id=176931
Tejun Heo <tj@kernel.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |tj@kernel.org
--- Comment #1 from Tejun Heo <tj@kernel.org> ---
Does booting with "irqpoll" boot option change anything?
--
You are receiving this mail because:
You are watching the assignee of the bug.
^ permalink raw reply
* [PATCH] ahci: qoriq: added ls1046a platform support
From: yuantian.tang @ 2016-10-09 8:51 UTC (permalink / raw)
To: tj; +Cc: linux-ide, linux-kernel, Tang Yuantian, Tang Yuantian
From: Tang Yuantian <Yuantian.Tang@nxp.com>
Ls1046a is a new introduced soc which supports ATA3.0.
Signed-off-by: Tang Yuantian <yuantian.tang@nxp.com>
---
drivers/ata/ahci_qoriq.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/drivers/ata/ahci_qoriq.c b/drivers/ata/ahci_qoriq.c
index 1eba8df..9884c8c 100644
--- a/drivers/ata/ahci_qoriq.c
+++ b/drivers/ata/ahci_qoriq.c
@@ -46,11 +46,13 @@
#define LS1021A_AXICC_ADDR 0xC0
#define SATA_ECC_DISABLE 0x00020000
+#define LS1046A_SATA_ECC_DIS 0x80000000
enum ahci_qoriq_type {
AHCI_LS1021A,
AHCI_LS1043A,
AHCI_LS2080A,
+ AHCI_LS1046A,
};
struct ahci_qoriq_priv {
@@ -63,6 +65,7 @@ static const struct of_device_id ahci_qoriq_of_match[] = {
{ .compatible = "fsl,ls1021a-ahci", .data = (void *)AHCI_LS1021A},
{ .compatible = "fsl,ls1043a-ahci", .data = (void *)AHCI_LS1043A},
{ .compatible = "fsl,ls2080a-ahci", .data = (void *)AHCI_LS2080A},
+ { .compatible = "fsl,ls1046a-ahci", .data = (void *)AHCI_LS1046A},
{},
};
MODULE_DEVICE_TABLE(of, ahci_qoriq_of_match);
@@ -175,6 +178,13 @@ static int ahci_qoriq_phy_init(struct ahci_host_priv *hpriv)
writel(AHCI_PORT_TRANS_CFG, reg_base + PORT_TRANS);
writel(AHCI_PORT_AXICC_CFG, reg_base + PORT_AXICC);
break;
+
+ case AHCI_LS1046A:
+ writel(LS1046A_SATA_ECC_DIS, qpriv->ecc_addr);
+ writel(AHCI_PORT_PHY_1_CFG, reg_base + PORT_PHY1);
+ writel(AHCI_PORT_TRANS_CFG, reg_base + PORT_TRANS);
+ writel(AHCI_PORT_AXICC_CFG, reg_base + PORT_AXICC);
+ break;
}
return 0;
@@ -204,9 +214,9 @@ static int ahci_qoriq_probe(struct platform_device *pdev)
qoriq_priv->type = (enum ahci_qoriq_type)of_id->data;
- if (qoriq_priv->type == AHCI_LS1021A) {
- res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
- "sata-ecc");
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+ "sata-ecc");
+ if (res) {
qoriq_priv->ecc_addr = devm_ioremap_resource(dev, res);
if (IS_ERR(qoriq_priv->ecc_addr))
return PTR_ERR(qoriq_priv->ecc_addr);
--
2.1.0.27.g96db324
^ permalink raw reply related
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