2020-11-04 15:16:40

by Deepak R Varma

Subject: [PATCH] drm/amdkfd: replace idr_init() by idr_init_base()

idr_init() uses base 0 which is an invalid identifier. The new function
idr_init_base allows IDR to set the ID lookup from base 1. This avoids
all lookups that otherwise starts from 0 since 0 is always unused.

References: commit 6ce711f27500 ("idr: Make 1-based IDRs more efficient")

Signed-off-by: Deepak R Varma <[email protected]>
---
drivers/gpu/drm/amd/amdkfd/kfd_events.c | 2 +-
drivers/gpu/drm/amd/amdkfd/kfd_process.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
index ba2c2ce0c55a..b3339b53c8ad 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_events.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
@@ -230,7 +230,7 @@ static int create_other_event(struct kfd_process *p, struct kfd_event *ev)
void kfd_event_init_process(struct kfd_process *p)
{
mutex_init(&p->event_mutex);
- idr_init(&p->event_idr);
+ idr_init_base(&p->event_idr, 1);
p->signal_page = NULL;
p->signal_event_count = 0;
}
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_process.c b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
index 65803e153a22..022e61babe30 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_process.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
@@ -1289,7 +1289,7 @@ struct kfd_process_device *kfd_create_process_device_data(struct kfd_dev *dev,
list_add(&pdd->per_device_list, &p->per_device_data);

/* Init idr used for memory handle translation */
- idr_init(&pdd->alloc_idr);
+ idr_init_base(&pdd->alloc_idr, 1);

return pdd;

--
2.25.1

2020-11-04 15:25:24

by Christian König

Subject: Re: [PATCH] drm/amdkfd: replace idr_init() by idr_init_base()

Am 04.11.20 um 16:13 schrieb Deepak R Varma:
> idr_init() uses base 0 which is an invalid identifier. The new function
> idr_init_base allows IDR to set the ID lookup from base 1. This avoids
> all lookups that otherwise starts from 0 since 0 is always unused.
>
> References: commit 6ce711f27500 ("idr: Make 1-based IDRs more efficient")
>
> Signed-off-by: Deepak R Varma <[email protected]>

Acked-by: Christian König <[email protected]>

> ---
> drivers/gpu/drm/amd/amdkfd/kfd_events.c | 2 +-
> drivers/gpu/drm/amd/amdkfd/kfd_process.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
> index ba2c2ce0c55a..b3339b53c8ad 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_events.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
> @@ -230,7 +230,7 @@ static int create_other_event(struct kfd_process *p, struct kfd_event *ev)
> void kfd_event_init_process(struct kfd_process *p)
> {
> mutex_init(&p->event_mutex);
> - idr_init(&p->event_idr);
> + idr_init_base(&p->event_idr, 1);
> p->signal_page = NULL;
> p->signal_event_count = 0;
> }
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_process.c b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> index 65803e153a22..022e61babe30 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> @@ -1289,7 +1289,7 @@ struct kfd_process_device *kfd_create_process_device_data(struct kfd_dev *dev,
> list_add(&pdd->per_device_list, &p->per_device_data);
>
> /* Init idr used for memory handle translation */
> - idr_init(&pdd->alloc_idr);
> + idr_init_base(&pdd->alloc_idr, 1);
>
> return pdd;
>

2020-11-05 01:33:58

by Felix Kuehling

Subject: Re: [PATCH] drm/amdkfd: replace idr_init() by idr_init_base()

On 2020-11-04 10:13 a.m., Deepak R Varma wrote:
> idr_init() uses base 0 which is an invalid identifier. The new function
> idr_init_base allows IDR to set the ID lookup from base 1. This avoids
> all lookups that otherwise starts from 0 since 0 is always unused.

I disagree. We call idr_alloc with start=0 for both these IDRs. That
means 0 seems to be a valid handle.

Regards,
  Felix


>
> References: commit 6ce711f27500 ("idr: Make 1-based IDRs more efficient")
>
> Signed-off-by: Deepak R Varma <[email protected]>
> ---
> drivers/gpu/drm/amd/amdkfd/kfd_events.c | 2 +-
> drivers/gpu/drm/amd/amdkfd/kfd_process.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
> index ba2c2ce0c55a..b3339b53c8ad 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_events.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
> @@ -230,7 +230,7 @@ static int create_other_event(struct kfd_process *p, struct kfd_event *ev)
> void kfd_event_init_process(struct kfd_process *p)
> {
> mutex_init(&p->event_mutex);
> - idr_init(&p->event_idr);
> + idr_init_base(&p->event_idr, 1);
> p->signal_page = NULL;
> p->signal_event_count = 0;
> }
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_process.c b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> index 65803e153a22..022e61babe30 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> @@ -1289,7 +1289,7 @@ struct kfd_process_device *kfd_create_process_device_data(struct kfd_dev *dev,
> list_add(&pdd->per_device_list, &p->per_device_data);
>
> /* Init idr used for memory handle translation */
> - idr_init(&pdd->alloc_idr);
> + idr_init_base(&pdd->alloc_idr, 1);
>
> return pdd;
>

2020-11-05 17:27:29

by Deepak R Varma

Subject: Re: [PATCH] drm/amdkfd: replace idr_init() by idr_init_base()

On Wed, Nov 04, 2020 at 03:01:17PM -0500, Felix Kuehling wrote:
> On 2020-11-04 10:13 a.m., Deepak R Varma wrote:
> > idr_init() uses base 0 which is an invalid identifier. The new function
> > idr_init_base allows IDR to set the ID lookup from base 1. This avoids
> > all lookups that otherwise starts from 0 since 0 is always unused.
>
> I disagree. We call idr_alloc with start=0 for both these IDRs. That means 0
> seems to be a valid handle.

Hello Felix,
You are correct. There are calls made to idr_alloc with start range from
0. So, for this driver, id=0 seems a valid use case. The change I
proposed is not relevant for this driver. You may please ignore the
patch.

Thank you,
./drv

>
> Regards,
> ? Felix
>
>
> >
> > References: commit 6ce711f27500 ("idr: Make 1-based IDRs more efficient")
> >
> > Signed-off-by: Deepak R Varma <[email protected]>
> > ---
> > drivers/gpu/drm/amd/amdkfd/kfd_events.c | 2 +-
> > drivers/gpu/drm/amd/amdkfd/kfd_process.c | 2 +-
> > 2 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
> > index ba2c2ce0c55a..b3339b53c8ad 100644
> > --- a/drivers/gpu/drm/amd/amdkfd/kfd_events.c
> > +++ b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
> > @@ -230,7 +230,7 @@ static int create_other_event(struct kfd_process *p, struct kfd_event *ev)
> > void kfd_event_init_process(struct kfd_process *p)
> > {
> > mutex_init(&p->event_mutex);
> > - idr_init(&p->event_idr);
> > + idr_init_base(&p->event_idr, 1);
> > p->signal_page = NULL;
> > p->signal_event_count = 0;
> > }
> > diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_process.c b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> > index 65803e153a22..022e61babe30 100644
> > --- a/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> > +++ b/drivers/gpu/drm/amd/amdkfd/kfd_process.c
> > @@ -1289,7 +1289,7 @@ struct kfd_process_device *kfd_create_process_device_data(struct kfd_dev *dev,
> > list_add(&pdd->per_device_list, &p->per_device_data);
> > /* Init idr used for memory handle translation */
> > - idr_init(&pdd->alloc_idr);
> > + idr_init_base(&pdd->alloc_idr, 1);
> > return pdd;