drivers/accel/habanalabs/common/device.c | 2 +- drivers/accel/habanalabs/common/habanalabs.h | 2 +- .../accel/habanalabs/common/habanalabs_drv.c | 17 ++++++++++------- 3 files changed, 12 insertions(+), 9 deletions(-)
Now that the driver core allows for struct class to be in read-only
memory, we should make all 'class' structures declared at build time
placing them into read-only memory, instead of having to be dynamically
allocated at runtime.
This requires some passing of const struct class * around in the common
habanalabs code as well as converting the structure itself.
Cc: Dafna Hirschfeld <dhirschfeld@habana.ai>
Cc: Dani Liberman <dliberman@habana.ai>
Cc: Koby Elbaz <kelbaz@habana.ai>
Cc: Oded Gabbay <ogabbay@kernel.org>
Cc: Ofir Bitton <obitton@habana.ai>
Cc: Ohad Sharabi <osharabi@habana.ai>
Cc: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
Cc: Tal Cohen <talcohen@habana.ai>
Cc: Tomer Tayar <ttayar@habana.ai>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/accel/habanalabs/common/device.c | 2 +-
drivers/accel/habanalabs/common/habanalabs.h | 2 +-
.../accel/habanalabs/common/habanalabs_drv.c | 17 ++++++++++-------
3 files changed, 12 insertions(+), 9 deletions(-)
diff --git a/drivers/accel/habanalabs/common/device.c b/drivers/accel/habanalabs/common/device.c
index b97339d1f7c6..4c28d8cfbb68 100644
--- a/drivers/accel/habanalabs/common/device.c
+++ b/drivers/accel/habanalabs/common/device.c
@@ -652,7 +652,7 @@ static void device_release_func(struct device *dev)
*
* Initialize a cdev and a Linux device for habanalabs's device.
*/
-static int device_init_cdev(struct hl_device *hdev, struct class *class,
+static int device_init_cdev(struct hl_device *hdev, const struct class *class,
int minor, const struct file_operations *fops,
char *name, struct cdev *cdev,
struct device **dev)
diff --git a/drivers/accel/habanalabs/common/habanalabs.h b/drivers/accel/habanalabs/common/habanalabs.h
index 2f027d5a8206..f1c78555e611 100644
--- a/drivers/accel/habanalabs/common/habanalabs.h
+++ b/drivers/accel/habanalabs/common/habanalabs.h
@@ -3308,7 +3308,7 @@ struct hl_device {
u64 pcie_bar_phys[HL_PCI_NUM_BARS];
void __iomem *pcie_bar[HL_PCI_NUM_BARS];
void __iomem *rmmio;
- struct class *hclass;
+ const struct class *hclass;
struct cdev cdev;
struct cdev cdev_ctrl;
struct device *dev;
diff --git a/drivers/accel/habanalabs/common/habanalabs_drv.c b/drivers/accel/habanalabs/common/habanalabs_drv.c
index 7263e84c1a4d..4f1fdff3843d 100644
--- a/drivers/accel/habanalabs/common/habanalabs_drv.c
+++ b/drivers/accel/habanalabs/common/habanalabs_drv.c
@@ -27,7 +27,11 @@ MODULE_DESCRIPTION(HL_DRIVER_DESC);
MODULE_LICENSE("GPL v2");
static int hl_major;
-static struct class *hl_class;
+
+static const struct class hl_class = {
+ .name = HL_NAME,
+};
+
static DEFINE_IDR(hl_devs_idr);
static DEFINE_MUTEX(hl_devs_idr_lock);
@@ -317,7 +321,7 @@ static void copy_kernel_module_params_to_device(struct hl_device *hdev)
hdev->asic_prop.fw_security_enabled = is_asic_secured(hdev->asic_type);
hdev->major = hl_major;
- hdev->hclass = hl_class;
+ hdev->hclass = &hl_class;
hdev->memory_scrub = memory_scrub;
hdev->reset_on_lockup = reset_on_lockup;
hdev->boot_error_status_mask = boot_error_status_mask;
@@ -691,10 +695,9 @@ static int __init hl_init(void)
hl_major = MAJOR(dev);
- hl_class = class_create(HL_NAME);
- if (IS_ERR(hl_class)) {
+ rc = class_register(&hl_class);
+ if (rc) {
pr_err("failed to allocate class\n");
- rc = PTR_ERR(hl_class);
goto remove_major;
}
@@ -712,7 +715,7 @@ static int __init hl_init(void)
remove_debugfs:
hl_debugfs_fini();
- class_destroy(hl_class);
+ class_unregister(&hl_class);
remove_major:
unregister_chrdev_region(MKDEV(hl_major, 0), HL_MAX_MINORS);
return rc;
@@ -732,7 +735,7 @@ static void __exit hl_exit(void)
*/
hl_debugfs_fini();
- class_destroy(hl_class);
+ class_unregister(&hl_class);
unregister_chrdev_region(MKDEV(hl_major, 0), HL_MAX_MINORS);
idr_destroy(&hl_devs_idr);
--
2.42.0On Fri, Oct 6, 2023 at 4:57 PM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> Now that the driver core allows for struct class to be in read-only
> memory, we should make all 'class' structures declared at build time
> placing them into read-only memory, instead of having to be dynamically
> allocated at runtime.
>
> This requires some passing of const struct class * around in the common
> habanalabs code as well as converting the structure itself.
Hi Greg,
Thanks for the patch but if you look at our tip of habanalabs-next
branch (to be merged in 6.7), you will see the hl_class related code
no longer exists, as we moved completely to the new accel char device
class.
So, I'm dropping this patch.
Oded
>
> Cc: Dafna Hirschfeld <dhirschfeld@habana.ai>
> Cc: Dani Liberman <dliberman@habana.ai>
> Cc: Koby Elbaz <kelbaz@habana.ai>
> Cc: Oded Gabbay <ogabbay@kernel.org>
> Cc: Ofir Bitton <obitton@habana.ai>
> Cc: Ohad Sharabi <osharabi@habana.ai>
> Cc: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
> Cc: Tal Cohen <talcohen@habana.ai>
> Cc: Tomer Tayar <ttayar@habana.ai>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
> drivers/accel/habanalabs/common/device.c | 2 +-
> drivers/accel/habanalabs/common/habanalabs.h | 2 +-
> .../accel/habanalabs/common/habanalabs_drv.c | 17 ++++++++++-------
> 3 files changed, 12 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/accel/habanalabs/common/device.c b/drivers/accel/habanalabs/common/device.c
> index b97339d1f7c6..4c28d8cfbb68 100644
> --- a/drivers/accel/habanalabs/common/device.c
> +++ b/drivers/accel/habanalabs/common/device.c
> @@ -652,7 +652,7 @@ static void device_release_func(struct device *dev)
> *
> * Initialize a cdev and a Linux device for habanalabs's device.
> */
> -static int device_init_cdev(struct hl_device *hdev, struct class *class,
> +static int device_init_cdev(struct hl_device *hdev, const struct class *class,
> int minor, const struct file_operations *fops,
> char *name, struct cdev *cdev,
> struct device **dev)
> diff --git a/drivers/accel/habanalabs/common/habanalabs.h b/drivers/accel/habanalabs/common/habanalabs.h
> index 2f027d5a8206..f1c78555e611 100644
> --- a/drivers/accel/habanalabs/common/habanalabs.h
> +++ b/drivers/accel/habanalabs/common/habanalabs.h
> @@ -3308,7 +3308,7 @@ struct hl_device {
> u64 pcie_bar_phys[HL_PCI_NUM_BARS];
> void __iomem *pcie_bar[HL_PCI_NUM_BARS];
> void __iomem *rmmio;
> - struct class *hclass;
> + const struct class *hclass;
> struct cdev cdev;
> struct cdev cdev_ctrl;
> struct device *dev;
> diff --git a/drivers/accel/habanalabs/common/habanalabs_drv.c b/drivers/accel/habanalabs/common/habanalabs_drv.c
> index 7263e84c1a4d..4f1fdff3843d 100644
> --- a/drivers/accel/habanalabs/common/habanalabs_drv.c
> +++ b/drivers/accel/habanalabs/common/habanalabs_drv.c
> @@ -27,7 +27,11 @@ MODULE_DESCRIPTION(HL_DRIVER_DESC);
> MODULE_LICENSE("GPL v2");
>
> static int hl_major;
> -static struct class *hl_class;
> +
> +static const struct class hl_class = {
> + .name = HL_NAME,
> +};
> +
> static DEFINE_IDR(hl_devs_idr);
> static DEFINE_MUTEX(hl_devs_idr_lock);
>
> @@ -317,7 +321,7 @@ static void copy_kernel_module_params_to_device(struct hl_device *hdev)
> hdev->asic_prop.fw_security_enabled = is_asic_secured(hdev->asic_type);
>
> hdev->major = hl_major;
> - hdev->hclass = hl_class;
> + hdev->hclass = &hl_class;
> hdev->memory_scrub = memory_scrub;
> hdev->reset_on_lockup = reset_on_lockup;
> hdev->boot_error_status_mask = boot_error_status_mask;
> @@ -691,10 +695,9 @@ static int __init hl_init(void)
>
> hl_major = MAJOR(dev);
>
> - hl_class = class_create(HL_NAME);
> - if (IS_ERR(hl_class)) {
> + rc = class_register(&hl_class);
> + if (rc) {
> pr_err("failed to allocate class\n");
> - rc = PTR_ERR(hl_class);
> goto remove_major;
> }
>
> @@ -712,7 +715,7 @@ static int __init hl_init(void)
>
> remove_debugfs:
> hl_debugfs_fini();
> - class_destroy(hl_class);
> + class_unregister(&hl_class);
> remove_major:
> unregister_chrdev_region(MKDEV(hl_major, 0), HL_MAX_MINORS);
> return rc;
> @@ -732,7 +735,7 @@ static void __exit hl_exit(void)
> */
> hl_debugfs_fini();
>
> - class_destroy(hl_class);
> + class_unregister(&hl_class);
> unregister_chrdev_region(MKDEV(hl_major, 0), HL_MAX_MINORS);
>
> idr_destroy(&hl_devs_idr);
> --
> 2.42.0
>
On Tue, Oct 10, 2023 at 09:07:53AM +0300, Oded Gabbay wrote: > On Fri, Oct 6, 2023 at 4:57 PM Greg Kroah-Hartman > <gregkh@linuxfoundation.org> wrote: > > > > Now that the driver core allows for struct class to be in read-only > > memory, we should make all 'class' structures declared at build time > > placing them into read-only memory, instead of having to be dynamically > > allocated at runtime. > > > > This requires some passing of const struct class * around in the common > > habanalabs code as well as converting the structure itself. > > Hi Greg, > Thanks for the patch but if you look at our tip of habanalabs-next > branch (to be merged in 6.7), you will see the hl_class related code > no longer exists, as we moved completely to the new accel char device > class. > So, I'm dropping this patch. Ah, no code is better, thanks! greg k-h
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