diff mbox series

[NDCTL,v3,2/2] cxl: Add check for regions before disabling memdev

Message ID 170138109724.2882696.123294980050048623.stgit@djiang5-mobl3
State New, archived
Headers show
Series None | expand

Commit Message

Dave Jiang Nov. 30, 2023, 9:51 p.m. UTC
Add a check for memdev disable to see if there are active regions present
before disabling the device. This is necessary now regions are present to
fulfill the TODO that was left there. The best way to determine if a
region is active is to see if there are decoders enabled for the mem
device. This is also best effort as the state is only a snapshot the
kernel provides and is not atomic WRT the memdev disable operation. The
expectation is the admin issuing the command has full control of the mem
device and there are no other agents also attempt to control the device.

Reviewed-by: Quanquan Cao <caoqq@fujitsu.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
v3:
- Add emission of warning for forcing operation. (Quanquan)
v2:
- Warn if active region regardless of -f. (Alison)
- Expound on -f behavior in man page. (Vishal)
---
 Documentation/cxl/cxl-disable-memdev.txt |    4 +++-
 cxl/memdev.c                             |   20 +++++++++++++++++---
 2 files changed, 20 insertions(+), 4 deletions(-)

Comments

Xingtao Yao (Fujitsu) April 17, 2024, 6:46 a.m. UTC | #1
Hi Dave,
  I have applied this patch in my env, and done a lot of testing, this
feature is currently working fine. 
  But it is not merged into master branch yet, are there any updates
on this feature?

Associated patches:
https://lore.kernel.org/linux-cxl/170112921107.2687457.2741231995154639197.stgit@djiang5-mobl3/
https://lore.kernel.org/linux-cxl/170120423159.2725915.14670830315829916850.stgit@djiang5-mobl3/

Thanks
Xingtao
Verma, Vishal L April 17, 2024, 6:14 p.m. UTC | #2
On Wed, 2024-04-17 at 02:46 -0400, Yao Xingtao wrote:
> 
> Hi Dave,
>   I have applied this patch in my env, and done a lot of testing,
> this
> feature is currently working fine. 
>   But it is not merged into master branch yet, are there any updates
> on this feature?

Hi Xingtao,

Turns out that I had applied this to a branch but forgot to merge and
push it. Thanks for the ping - done now, and pushed to pending.

> 
> Associated patches:
> https://lore.kernel.org/linux-cxl/170112921107.2687457.2741231995154639197.stgit@djiang5-mobl3/
> https://lore.kernel.org/linux-cxl/170120423159.2725915.14670830315829916850.stgit@djiang5-mobl3/
> 
> Thanks
> Xingtao
Xingtao Yao (Fujitsu) April 22, 2024, 7:26 a.m. UTC | #3
> -----Original Message-----
> From: Verma, Vishal L <vishal.l.verma@intel.com>
> Sent: Thursday, April 18, 2024 2:14 AM
> To: Jiang, Dave <dave.jiang@intel.com>; Yao, Xingtao/姚 幸涛
> <yaoxt.fnst@fujitsu.com>
> Cc: Cao, Quanquan/曹 全全 <caoqq@fujitsu.com>; linux-cxl@vger.kernel.org;
> nvdimm@lists.linux.dev
> Subject: Re:
> 
> On Wed, 2024-04-17 at 02:46 -0400, Yao Xingtao wrote:
> >
> > Hi Dave,
> >   I have applied this patch in my env, and done a lot of testing,
> > this
> > feature is currently working fine.
> >   But it is not merged into master branch yet, are there any updates
> > on this feature?
> 
> Hi Xingtao,
> 
> Turns out that I had applied this to a branch but forgot to merge and
> push it. Thanks for the ping - done now, and pushed to pending.
Awesome, many thanks!!!

> 
> >
> > Associated patches:
> >
> https://lore.kernel.org/linux-cxl/170112921107.2687457.2741231995154639197.st
> git@djiang5-mobl3/
> >
> https://lore.kernel.org/linux-cxl/170120423159.2725915.14670830315829916850.s
> tgit@djiang5-mobl3/
> >
> > Thanks
> > Xingtao
Zhijian Li (Fujitsu) April 25, 2024, 5:30 a.m. UTC | #4
Hi Verma,


On 18/04/2024 02:14, Verma, Vishal L wrote:
> On Wed, 2024-04-17 at 02:46 -0400, Yao Xingtao wrote:
>>
>> Hi Dave,
>>    I have applied this patch in my env, and done a lot of testing,
>> this
>> feature is currently working fine.
>>    But it is not merged into master branch yet, are there any updates
>> on this feature?
> 
> Hi Xingtao,
> 
> Turns out that I had applied this to a branch but forgot to merge and
> push it. Thanks for the ping - done now, and pushed to pending.


May I know when the next version of NDCTL will be released. It seems like
it's been a very long time since the last release.



Thanks
Zhijian




> 
>>
>> Associated patches:
>> https://lore.kernel.org/linux-cxl/170112921107.2687457.2741231995154639197.stgit@djiang5-mobl3/
>> https://lore.kernel.org/linux-cxl/170120423159.2725915.14670830315829916850.stgit@djiang5-mobl3/
>>
>> Thanks
>> Xingtao
>
Alison Schofield April 25, 2024, 4:52 p.m. UTC | #5
On Thu, Apr 25, 2024 at 05:30:40AM +0000, Zhijian Li (Fujitsu) wrote:
> Hi Verma,
> 
> 
> On 18/04/2024 02:14, Verma, Vishal L wrote:
> > On Wed, 2024-04-17 at 02:46 -0400, Yao Xingtao wrote:
> >>
> >> Hi Dave,
> >>    I have applied this patch in my env, and done a lot of testing,
> >> this
> >> feature is currently working fine.
> >>    But it is not merged into master branch yet, are there any updates
> >> on this feature?
> > 
> > Hi Xingtao,
> > 
> > Turns out that I had applied this to a branch but forgot to merge and
> > push it. Thanks for the ping - done now, and pushed to pending.
> 
> 
> May I know when the next version of NDCTL will be released. It seems like
> it's been a very long time since the last release.

Hi Zhijian,

We appreciate you working with the pending branch while waiting
for the next release. We are aiming to get the poison list feature
merged in the next release, and are getting closer. That's all I
can offer, no date prediction.

-- Alison

> 
> 
> Thanks
> Zhijian
> 
> 
> 
> 
> > 
> >>
> >> Associated patches:
> >> https://lore.kernel.org/linux-cxl/170112921107.2687457.2741231995154639197.stgit@djiang5-mobl3/
> >> https://lore.kernel.org/linux-cxl/170120423159.2725915.14670830315829916850.stgit@djiang5-mobl3/
> >>
> >> Thanks
> >> Xingtao
> >
Zhijian Li (Fujitsu) April 26, 2024, 1:57 a.m. UTC | #6
On 26/04/2024 00:52, Alison Schofield wrote:
> On Thu, Apr 25, 2024 at 05:30:40AM +0000, Zhijian Li (Fujitsu) wrote:
>> Hi Verma,
>>
>>
>> On 18/04/2024 02:14, Verma, Vishal L wrote:
>>> On Wed, 2024-04-17 at 02:46 -0400, Yao Xingtao wrote:
>>>>
>>>> Hi Dave,
>>>>     I have applied this patch in my env, and done a lot of testing,
>>>> this
>>>> feature is currently working fine.
>>>>     But it is not merged into master branch yet, are there any updates
>>>> on this feature?
>>>
>>> Hi Xingtao,
>>>
>>> Turns out that I had applied this to a branch but forgot to merge and
>>> push it. Thanks for the ping - done now, and pushed to pending.
>>
>>
>> May I know when the next version of NDCTL will be released. It seems like
>> it's been a very long time since the last release.
> 
> Hi Zhijian,
> 
> We appreciate you working with the pending branch while waiting
> for the next release. We are aiming to get the poison list feature
> merged in the next release, and are getting closer. That's all I
> can offer, no date prediction.

Understood, thanks for your information.


Thanks
Zhijian

> 
> -- Alison
> 
>>
>>
>> Thanks
>> Zhijian
>>
>>
>>
>>
>>>
>>>>
>>>> Associated patches:
>>>> https://lore.kernel.org/linux-cxl/170112921107.2687457.2741231995154639197.stgit@djiang5-mobl3/
>>>> https://lore.kernel.org/linux-cxl/170120423159.2725915.14670830315829916850.stgit@djiang5-mobl3/
>>>>
>>>> Thanks
>>>> Xingtao
>>>
diff mbox series

Patch

diff --git a/Documentation/cxl/cxl-disable-memdev.txt b/Documentation/cxl/cxl-disable-memdev.txt
index c4edb93ee94a..34b720288705 100644
--- a/Documentation/cxl/cxl-disable-memdev.txt
+++ b/Documentation/cxl/cxl-disable-memdev.txt
@@ -27,7 +27,9 @@  include::bus-option.txt[]
 	a device if the tool determines the memdev is in active usage. Recall
 	that CXL memory ranges might have been established by platform
 	firmware and disabling an active device is akin to force removing
-	memory from a running system.
+	memory from a running system. Going down this path does not offline
+	active memory if they are currently online. User is recommended to
+	offline and disable the appropriate regions before disabling the memdevs.
 
 -v::
 	Turn on verbose debug messages in the library (if libcxl was built with
diff --git a/cxl/memdev.c b/cxl/memdev.c
index 2dd2e7fcc4dd..ed962d478048 100644
--- a/cxl/memdev.c
+++ b/cxl/memdev.c
@@ -437,14 +437,28 @@  static int action_free_dpa(struct cxl_memdev *memdev,
 
 static int action_disable(struct cxl_memdev *memdev, struct action_context *actx)
 {
+	struct cxl_endpoint *ep;
+	struct cxl_port *port;
+
 	if (!cxl_memdev_is_enabled(memdev))
 		return 0;
 
-	if (!param.force) {
-		/* TODO: actually detect rather than assume active */
+	ep = cxl_memdev_get_endpoint(memdev);
+	if (!ep)
+		return -ENODEV;
+
+	port = cxl_endpoint_get_port(ep);
+	if (!port)
+		return -ENODEV;
+
+	if (cxl_port_decoders_committed(port)) {
 		log_err(&ml, "%s is part of an active region\n",
 			cxl_memdev_get_devname(memdev));
-		return -EBUSY;
+		if (!param.force)
+			return -EBUSY;
+
+		log_err(&ml, "Forcing %s disable with an active region!\n",
+			cxl_memdev_get_devname(memdev));
 	}
 
 	return cxl_memdev_disable_invalidate(memdev);