Hi,
This is the second version where I only modified the commit message of
the first patch according to comments from Bjorn.
Original cover letter:
There is one user left for the API, so converting that to use software
node API instead, and removing the function.
thanks,
Heikki Krogerus (2):
PCI: Convert to device_create_managed_software_node()
device property: Remove device_add_properties() API
drivers/base/core.c | 1 -
drivers/base/property.c | 48 ----------------------------------------
drivers/pci/quirks.c | 2 +-
include/linux/property.h | 4 ----
4 files changed, 1 insertion(+), 54 deletions(-)
--
2.33.0
In quirk_huawei_pcie_sva(), use device_create_managed_software_node()
instead of device_add_properties() to set the "dma-can-stall"
property.
Reviewed-by: Andy Shevchenko <[email protected]>
Acked-by: Zhangfei Gao <[email protected]>
Signed-off-by: Heikki Krogerus <[email protected]>
---
Hi,
The commit message now says what Bjorn requested, except I left out
the claim that the patch fixes a lifetime issue.
There shouldn't be any functional impact.
thanks,
---
drivers/pci/quirks.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index b6b4c803bdc94..fe5eedba47908 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -1850,7 +1850,7 @@ static void quirk_huawei_pcie_sva(struct pci_dev *pdev)
* can set it directly.
*/
if (!pdev->dev.of_node &&
- device_add_properties(&pdev->dev, properties))
+ device_create_managed_software_node(&pdev->dev, properties, NULL))
pci_warn(pdev, "could not add stall property");
}
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa250, quirk_huawei_pcie_sva);
--
2.33.0
On Thu, Sep 30, 2021 at 03:12:45PM +0300, Heikki Krogerus wrote:
> In quirk_huawei_pcie_sva(), use device_create_managed_software_node()
> instead of device_add_properties() to set the "dma-can-stall"
> property.
>
> Reviewed-by: Andy Shevchenko <[email protected]>
> Acked-by: Zhangfei Gao <[email protected]>
> Signed-off-by: Heikki Krogerus <[email protected]>
> ---
> Hi,
>
> The commit message now says what Bjorn requested, except I left out
> the claim that the patch fixes a lifetime issue.
Thanks.
The commit log should help reviewers determine whether the change is
safe and necessary. So far it doesn't have any hints along that line.
Comparing device_add_properties() [1] and
device_create_managed_software_node() [2], the only difference in this
case is that the latter sets "swnode->managed = true". The function
comment says "managed" means the lifetime of the swnode is tied to the
lifetime of dev, hence my question about a lifetime issue.
I can see that one reason for this change is to remove the last caller
of device_add_properties(), so device_add_properties() itself can be
removed. That's a good reason for wanting to do it, and the commit
log could mention it.
But it doesn't help me figure out whether it's safe. For that,
I need to know the effect of setting "managed = true". Obviously
it means *something*, but I don't know what. It looks like the only
test is in software_node_notify():
device_del
device_platform_notify_remove
software_node_notify_remove
sysfs_remove_link(dev_name)
sysfs_remove_link("software_node")
if (swnode->managed) <--
set_secondary_fwnode(dev, NULL)
kobject_put(&swnode->kobj)
device_remove_properties
if (is_software_node())
fwnode_remove_software_node
kobject_put(&swnode->kobj)
set_secondary_fwnode(dev, NULL)
I'm not sure what's going on here; it looks like some redundancy with
multiple calls of kobject_put() and set_secondary_fwnode(). Maybe you
are in the process of removing device_remove_properties() as well as
device_add_properties()?
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/base/property.c?id=v5.14#n533
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/base/swnode.c?id=v5.14#n1083
> There shouldn't be any functional impact.
>
> thanks,
> ---
> drivers/pci/quirks.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index b6b4c803bdc94..fe5eedba47908 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -1850,7 +1850,7 @@ static void quirk_huawei_pcie_sva(struct pci_dev *pdev)
> * can set it directly.
> */
> if (!pdev->dev.of_node &&
> - device_add_properties(&pdev->dev, properties))
> + device_create_managed_software_node(&pdev->dev, properties, NULL))
> pci_warn(pdev, "could not add stall property");
> }
> DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa250, quirk_huawei_pcie_sva);
> --
> 2.33.0
>
On Thu, Sep 30, 2021 at 10:04:02AM -0500, Bjorn Helgaas wrote:
> On Thu, Sep 30, 2021 at 03:12:45PM +0300, Heikki Krogerus wrote:
> > In quirk_huawei_pcie_sva(), use device_create_managed_software_node()
> > instead of device_add_properties() to set the "dma-can-stall"
> > property.
> >
> > Reviewed-by: Andy Shevchenko <[email protected]>
> > Acked-by: Zhangfei Gao <[email protected]>
> > Signed-off-by: Heikki Krogerus <[email protected]>
> > ---
> > Hi,
> >
> > The commit message now says what Bjorn requested, except I left out
> > the claim that the patch fixes a lifetime issue.
>
> Thanks.
>
> The commit log should help reviewers determine whether the change is
> safe and necessary. So far it doesn't have any hints along that line.
>
> Comparing device_add_properties() [1] and
> device_create_managed_software_node() [2], the only difference in this
> case is that the latter sets "swnode->managed = true". The function
> comment says "managed" means the lifetime of the swnode is tied to the
> lifetime of dev, hence my question about a lifetime issue.
>
> I can see that one reason for this change is to remove the last caller
> of device_add_properties(), so device_add_properties() itself can be
> removed. That's a good reason for wanting to do it, and the commit
> log could mention it.
Fair enough. I need to explain the why as well as the what.
I'll improve the commit message, but just to be clear, the goal is
actually not to get rid of device_add_properties(). It is removed in
the second patch together with device_remove_properties() because
there are simply no more users for that API.
> But it doesn't help me figure out whether it's safe. For that,
> I need to know the effect of setting "managed = true". Obviously
> it means *something*, but I don't know what. It looks like the only
> test is in software_node_notify():
>
> device_del
> device_platform_notify_remove
> software_node_notify_remove
> sysfs_remove_link(dev_name)
> sysfs_remove_link("software_node")
> if (swnode->managed) <--
> set_secondary_fwnode(dev, NULL)
> kobject_put(&swnode->kobj)
> device_remove_properties
> if (is_software_node())
> fwnode_remove_software_node
> kobject_put(&swnode->kobj)
> set_secondary_fwnode(dev, NULL)
>
> I'm not sure what's going on here; it looks like some redundancy with
> multiple calls of kobject_put() and set_secondary_fwnode(). Maybe you
> are in the process of removing device_remove_properties() as well as
> device_add_properties()?
It'll get removed, but that's not the goal. The goal is to get rid of
the call to it in device_del(), so not the function itself. That call
is the problem here as explained in commit 151f6ff78cdf ("software
node: Provide replacement for device_add_properties()").
I'll split the second patch, and first only remove that
device_remove_properties() call from device_del(), and only after
that remove the functions themselves.
thanks,
--
heikki
On Fri, Oct 1, 2021 at 12:36 PM Heikki Krogerus
<[email protected]> wrote:
>
> On Thu, Sep 30, 2021 at 10:04:02AM -0500, Bjorn Helgaas wrote:
> > On Thu, Sep 30, 2021 at 03:12:45PM +0300, Heikki Krogerus wrote:
> > > In quirk_huawei_pcie_sva(), use device_create_managed_software_node()
> > > instead of device_add_properties() to set the "dma-can-stall"
> > > property.
> > >
> > > Reviewed-by: Andy Shevchenko <[email protected]>
> > > Acked-by: Zhangfei Gao <[email protected]>
> > > Signed-off-by: Heikki Krogerus <[email protected]>
> > > ---
> > > Hi,
> > >
> > > The commit message now says what Bjorn requested, except I left out
> > > the claim that the patch fixes a lifetime issue.
> >
> > Thanks.
> >
> > The commit log should help reviewers determine whether the change is
> > safe and necessary. So far it doesn't have any hints along that line.
> >
> > Comparing device_add_properties() [1] and
> > device_create_managed_software_node() [2], the only difference in this
> > case is that the latter sets "swnode->managed = true". The function
> > comment says "managed" means the lifetime of the swnode is tied to the
> > lifetime of dev, hence my question about a lifetime issue.
> >
> > I can see that one reason for this change is to remove the last caller
> > of device_add_properties(), so device_add_properties() itself can be
> > removed. That's a good reason for wanting to do it, and the commit
> > log could mention it.
>
> Fair enough. I need to explain the why as well as the what.
>
> I'll improve the commit message, but just to be clear, the goal is
> actually not to get rid of device_add_properties(). It is removed in
> the second patch together with device_remove_properties() because
> there are simply no more users for that API.
>
> > But it doesn't help me figure out whether it's safe. For that,
> > I need to know the effect of setting "managed = true". Obviously
> > it means *something*, but I don't know what. It looks like the only
> > test is in software_node_notify():
> >
> > device_del
> > device_platform_notify_remove
> > software_node_notify_remove
> > sysfs_remove_link(dev_name)
> > sysfs_remove_link("software_node")
> > if (swnode->managed) <--
> > set_secondary_fwnode(dev, NULL)
> > kobject_put(&swnode->kobj)
> > device_remove_properties
> > if (is_software_node())
> > fwnode_remove_software_node
> > kobject_put(&swnode->kobj)
> > set_secondary_fwnode(dev, NULL)
> >
> > I'm not sure what's going on here; it looks like some redundancy with
> > multiple calls of kobject_put() and set_secondary_fwnode(). Maybe you
> > are in the process of removing device_remove_properties() as well as
> > device_add_properties()?
>
> It'll get removed, but that's not the goal. The goal is to get rid of
> the call to it in device_del(), so not the function itself. That call
> is the problem here as explained in commit 151f6ff78cdf ("software
> node: Provide replacement for device_add_properties()").
>
> I'll split the second patch, and first only remove that
> device_remove_properties() call from device_del(), and only after
> that remove the functions themselves.
So I'm expecting a v3 of this.
On Tue, Oct 05, 2021 at 04:04:48PM +0200, Rafael J. Wysocki wrote:
> So I'm expecting a v3 of this.
Yes, sorry for the delay. v3 coming up.
thanks,
--
heikki