* [PATCH] drm/panfrost:modify 'break' to 'continue' to traverse the circulation @ 2021-06-17 8:04 ` ChunyouTang 0 siblings, 0 replies; 7+ messages in thread From: ChunyouTang @ 2021-06-17 8:04 UTC (permalink / raw) To: robh, tomeu.vizoso, steven.price, alyssa.rosenzweig, airlied, daniel Cc: dri-devel, linux-kernel, ChunyouTang From: ChunyouTang <tangchunyou@icubecorp.cn> The 'break' can cause 'Memory manager not clean during takedown' It cannot use break to finish the circulation,it should use continue to traverse the circulation.it should put every mapping which is not NULL. Signed-off-by: ChunyouTang <tangchunyou@icubecorp.cn> --- drivers/gpu/drm/panfrost/panfrost_job.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c index 6003cfeb1322..52bccc1d2d42 100644 --- a/drivers/gpu/drm/panfrost/panfrost_job.c +++ b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -281,7 +281,7 @@ static void panfrost_job_cleanup(struct kref *ref) if (job->mappings) { for (i = 0; i < job->bo_count; i++) { if (!job->mappings[i]) - break; + continue; atomic_dec(&job->mappings[i]->obj->gpu_usecount); panfrost_gem_mapping_put(job->mappings[i]); -- 2.25.1 ^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH] drm/panfrost:modify 'break' to 'continue' to traverse the circulation @ 2021-06-17 8:04 ` ChunyouTang 0 siblings, 0 replies; 7+ messages in thread From: ChunyouTang @ 2021-06-17 8:04 UTC (permalink / raw) To: robh, tomeu.vizoso, steven.price, alyssa.rosenzweig, airlied, daniel Cc: ChunyouTang, linux-kernel, dri-devel From: ChunyouTang <tangchunyou@icubecorp.cn> The 'break' can cause 'Memory manager not clean during takedown' It cannot use break to finish the circulation,it should use continue to traverse the circulation.it should put every mapping which is not NULL. Signed-off-by: ChunyouTang <tangchunyou@icubecorp.cn> --- drivers/gpu/drm/panfrost/panfrost_job.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c index 6003cfeb1322..52bccc1d2d42 100644 --- a/drivers/gpu/drm/panfrost/panfrost_job.c +++ b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -281,7 +281,7 @@ static void panfrost_job_cleanup(struct kref *ref) if (job->mappings) { for (i = 0; i < job->bo_count; i++) { if (!job->mappings[i]) - break; + continue; atomic_dec(&job->mappings[i]->obj->gpu_usecount); panfrost_gem_mapping_put(job->mappings[i]); -- 2.25.1 ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH] drm/panfrost:modify 'break' to 'continue' to traverse the circulation 2021-06-17 8:04 ` ChunyouTang (?) @ 2021-06-18 12:43 ` Steven Price 2021-06-19 3:09 ` Chunyou Tang -1 siblings, 1 reply; 7+ messages in thread From: Steven Price @ 2021-06-18 12:43 UTC (permalink / raw) To: ChunyouTang, robh, tomeu.vizoso, alyssa.rosenzweig, airlied, daniel Cc: ChunyouTang, linux-kernel, dri-devel On 17/06/2021 09:04, ChunyouTang wrote: > From: ChunyouTang <tangchunyou@icubecorp.cn> > > The 'break' can cause 'Memory manager not clean during takedown' > > It cannot use break to finish the circulation,it should use > > continue to traverse the circulation.it should put every mapping > > which is not NULL. You don't appear to have answered my question about whether you've actually seen this happen (and ideally what circumstances). In my previous email[1] I explained why I don't think this is needed. You need to convince me that I've overlooked something. Thanks, Steve [1] https://lore.kernel.org/r/31644881-134a-2d6e-dddf-e658a3a8176b%40arm.com > Signed-off-by: ChunyouTang <tangchunyou@icubecorp.cn> > --- > drivers/gpu/drm/panfrost/panfrost_job.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c > index 6003cfeb1322..52bccc1d2d42 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_job.c > +++ b/drivers/gpu/drm/panfrost/panfrost_job.c > @@ -281,7 +281,7 @@ static void panfrost_job_cleanup(struct kref *ref) > if (job->mappings) { > for (i = 0; i < job->bo_count; i++) { > if (!job->mappings[i]) > - break; > + continue; > > atomic_dec(&job->mappings[i]->obj->gpu_usecount); > panfrost_gem_mapping_put(job->mappings[i]); > ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] drm/panfrost:modify 'break' to 'continue' to traverse the circulation 2021-06-18 12:43 ` Steven Price @ 2021-06-19 3:09 ` Chunyou Tang 0 siblings, 0 replies; 7+ messages in thread From: Chunyou Tang @ 2021-06-19 3:09 UTC (permalink / raw) To: Steven Price Cc: robh, tomeu.vizoso, alyssa.rosenzweig, airlied, daniel, ChunyouTang, linux-kernel, dri-devel [-- Warning: decoded text below may be mangled, UTF-8 assumed --] [-- Attachment #1: Type: text/plain; charset=GB18030, Size: 3368 bytes --] Hi Steve, 1, from https://lore.kernel.org/lkml/31644881-134a-2d6e-dddf-e658a3a8176b@arm.com/ I can see what your sent,I used a wrong email address,Now it correct. 2, > >Unless I'm mistaken the situation where some mappings may be NULL is > >caused by the loop in panfrost_lookup_bos() not completing > >successfully > >(panfrost_gem_mapping_get() returning NULL). In this case if > >mappings[i] > >is NULL then all following mappings must also be NULL. So 'break' > >allows > >us to skip the later ones. Admittedly the performance here isn't > >important so I'm not sure it's worth the optimisation, but AIUI this > >code isn't actually wrong. from panfrost_lookup_bos(),you can see: for (i = 0; i < job->bo_count; i++) { struct panfrost_gem_mapping *mapping; bo = to_panfrost_bo(job->bos[i]); ICUBE_DEBUG_PRINTK("panfrost bo gem handle=0x%x is_dumb=%d\n", bo->gem_handle, bo->is_dumb); if (!bo->is_dumb) { mapping = panfrost_gem_mapping_get(bo, priv); if (!mapping) { ret = -EINVAL; break; } atomic_inc(&bo->gpu_usecount); job->mappings[i] = mapping; } else { atomic_inc(&bo->gpu_usecount); job->mappings[i] = NULL; } } if bo->is_dumb is TRUE,the job->mappings[i] will set to NULL,and the while will be continue,so if job->mappings[i] is NULL,the following can not be NULL. 3, I've had this problem in our project,the value of is_dumb like these: 0 0 0 1 0 0 0 so,when job->mappings[i] is NULL,we can not break the while in panfrost_job_cleanup(). thanks Chunyou ÓÚ Fri, 18 Jun 2021 13:43:25 +0100 Steven Price <steven.price@arm.com> дµÀ: > On 17/06/2021 09:04, ChunyouTang wrote: > > From: ChunyouTang <tangchunyou@icubecorp.cn> > > > > The 'break' can cause 'Memory manager not clean during takedown' > > > > It cannot use break to finish the circulation,it should use > > > > continue to traverse the circulation.it should put every mapping > > > > which is not NULL. > > You don't appear to have answered my question about whether you've > actually seen this happen (and ideally what circumstances). In my > previous email[1] I explained why I don't think this is needed. You > need to convince me that I've overlooked something. > > Thanks, > > Steve > > [1] > https://lore.kernel.org/r/31644881-134a-2d6e-dddf-e658a3a8176b%40arm.com > > > Signed-off-by: ChunyouTang <tangchunyou@icubecorp.cn> > > --- > > drivers/gpu/drm/panfrost/panfrost_job.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c > > b/drivers/gpu/drm/panfrost/panfrost_job.c index > > 6003cfeb1322..52bccc1d2d42 100644 --- > > a/drivers/gpu/drm/panfrost/panfrost_job.c +++ > > b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -281,7 +281,7 @@ > > static void panfrost_job_cleanup(struct kref *ref) if > > (job->mappings) { for (i = 0; i < job->bo_count; i++) { > > if (!job->mappings[i]) > > - break; > > + continue; > > > > atomic_dec(&job->mappings[i]->obj->gpu_usecount); > > panfrost_gem_mapping_put(job->mappings[i]); > > ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] drm/panfrost:modify 'break' to 'continue' to traverse the circulation @ 2021-06-19 3:09 ` Chunyou Tang 0 siblings, 0 replies; 7+ messages in thread From: Chunyou Tang @ 2021-06-19 3:09 UTC (permalink / raw) To: Steven Price Cc: tomeu.vizoso, airlied, linux-kernel, dri-devel, alyssa.rosenzweig, ChunyouTang [-- Warning: decoded text below may be mangled, UTF-8 assumed --] [-- Attachment #1: Type: text/plain; charset=GB18030, Size: 3368 bytes --] Hi Steve, 1, from https://lore.kernel.org/lkml/31644881-134a-2d6e-dddf-e658a3a8176b@arm.com/ I can see what your sent,I used a wrong email address,Now it correct. 2, > >Unless I'm mistaken the situation where some mappings may be NULL is > >caused by the loop in panfrost_lookup_bos() not completing > >successfully > >(panfrost_gem_mapping_get() returning NULL). In this case if > >mappings[i] > >is NULL then all following mappings must also be NULL. So 'break' > >allows > >us to skip the later ones. Admittedly the performance here isn't > >important so I'm not sure it's worth the optimisation, but AIUI this > >code isn't actually wrong. from panfrost_lookup_bos(),you can see: for (i = 0; i < job->bo_count; i++) { struct panfrost_gem_mapping *mapping; bo = to_panfrost_bo(job->bos[i]); ICUBE_DEBUG_PRINTK("panfrost bo gem handle=0x%x is_dumb=%d\n", bo->gem_handle, bo->is_dumb); if (!bo->is_dumb) { mapping = panfrost_gem_mapping_get(bo, priv); if (!mapping) { ret = -EINVAL; break; } atomic_inc(&bo->gpu_usecount); job->mappings[i] = mapping; } else { atomic_inc(&bo->gpu_usecount); job->mappings[i] = NULL; } } if bo->is_dumb is TRUE,the job->mappings[i] will set to NULL,and the while will be continue,so if job->mappings[i] is NULL,the following can not be NULL. 3, I've had this problem in our project,the value of is_dumb like these: 0 0 0 1 0 0 0 so,when job->mappings[i] is NULL,we can not break the while in panfrost_job_cleanup(). thanks Chunyou ÓÚ Fri, 18 Jun 2021 13:43:25 +0100 Steven Price <steven.price@arm.com> дµÀ: > On 17/06/2021 09:04, ChunyouTang wrote: > > From: ChunyouTang <tangchunyou@icubecorp.cn> > > > > The 'break' can cause 'Memory manager not clean during takedown' > > > > It cannot use break to finish the circulation,it should use > > > > continue to traverse the circulation.it should put every mapping > > > > which is not NULL. > > You don't appear to have answered my question about whether you've > actually seen this happen (and ideally what circumstances). In my > previous email[1] I explained why I don't think this is needed. You > need to convince me that I've overlooked something. > > Thanks, > > Steve > > [1] > https://lore.kernel.org/r/31644881-134a-2d6e-dddf-e658a3a8176b%40arm.com > > > Signed-off-by: ChunyouTang <tangchunyou@icubecorp.cn> > > --- > > drivers/gpu/drm/panfrost/panfrost_job.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c > > b/drivers/gpu/drm/panfrost/panfrost_job.c index > > 6003cfeb1322..52bccc1d2d42 100644 --- > > a/drivers/gpu/drm/panfrost/panfrost_job.c +++ > > b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -281,7 +281,7 @@ > > static void panfrost_job_cleanup(struct kref *ref) if > > (job->mappings) { for (i = 0; i < job->bo_count; i++) { > > if (!job->mappings[i]) > > - break; > > + continue; > > > > atomic_dec(&job->mappings[i]->obj->gpu_usecount); > > panfrost_gem_mapping_put(job->mappings[i]); > > ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] drm/panfrost:modify 'break' to 'continue' to traverse the circulation 2021-06-19 3:09 ` Chunyou Tang (?) @ 2021-06-21 10:45 ` Steven Price 2021-06-22 1:31 ` Chunyou Tang -1 siblings, 1 reply; 7+ messages in thread From: Steven Price @ 2021-06-21 10:45 UTC (permalink / raw) To: Chunyou Tang Cc: tomeu.vizoso, airlied, linux-kernel, dri-devel, alyssa.rosenzweig, ChunyouTang [-- Warning: decoded text below may be mangled, UTF-8 assumed --] [-- Attachment #1: Type: text/plain; charset=gb18030, Size: 3886 bytes --] On 19/06/2021 04:09, Chunyou Tang wrote: > Hi Steve, > 1, > from > https://lore.kernel.org/lkml/31644881-134a-2d6e-dddf-e658a3a8176b@arm.com/ > I can see what your sent,I used a wrong email address,Now it correct. > 2, >>> Unless I'm mistaken the situation where some mappings may be NULL is >>> caused by the loop in panfrost_lookup_bos() not completing >>> successfully >>> (panfrost_gem_mapping_get() returning NULL). In this case if >>> mappings[i] >>> is NULL then all following mappings must also be NULL. So 'break' >>> allows >>> us to skip the later ones. Admittedly the performance here isn't >>> important so I'm not sure it's worth the optimisation, but AIUI this >>> code isn't actually wrong. > > from panfrost_lookup_bos(),you can see: > for (i = 0; i < job->bo_count; i++) { > struct panfrost_gem_mapping *mapping; > > bo = to_panfrost_bo(job->bos[i]); > ICUBE_DEBUG_PRINTK("panfrost bo gem handle=0x%x > is_dumb=%d\n", bo->gem_handle, bo->is_dumb); > if (!bo->is_dumb) { > mapping = panfrost_gem_mapping_get(bo, priv); > if (!mapping) { > ret = -EINVAL; > break; > } > > atomic_inc(&bo->gpu_usecount); > job->mappings[i] = mapping; > } else { > atomic_inc(&bo->gpu_usecount); > job->mappings[i] = NULL; > } > } This code isn't upstream - in drm-misc/drm-misc-next (and all mainline kernels from what I can tell) this doesn't have any "is_dumb" test. Which branch are you using? > if bo->is_dumb is TRUE,the job->mappings[i] will set to NULL,and the > while will be continue,so if job->mappings[i] is NULL,the following > can not be NULL. I agree that with the above code the panfrost_job_cleanup() would need changing. But we don't (currently) have this code upstream, so this change doesn't make sense upstream. Thanks, Steve > 3, > I've had this problem in our project,the value of is_dumb like these: > 0 > 0 > 0 > 1 > 0 > 0 > 0 > so,when job->mappings[i] is NULL,we can not break the while in > panfrost_job_cleanup(). > > thanks > Chunyou > > ÓÚ Fri, 18 Jun 2021 13:43:25 +0100 > Steven Price <steven.price@arm.com> дµÀ: > >> On 17/06/2021 09:04, ChunyouTang wrote: >>> From: ChunyouTang <tangchunyou@icubecorp.cn> >>> >>> The 'break' can cause 'Memory manager not clean during takedown' >>> >>> It cannot use break to finish the circulation,it should use >>> >>> continue to traverse the circulation.it should put every mapping >>> >>> which is not NULL. >> >> You don't appear to have answered my question about whether you've >> actually seen this happen (and ideally what circumstances). In my >> previous email[1] I explained why I don't think this is needed. You >> need to convince me that I've overlooked something. >> >> Thanks, >> >> Steve >> >> [1] >> https://lore.kernel.org/r/31644881-134a-2d6e-dddf-e658a3a8176b%40arm.com >> >>> Signed-off-by: ChunyouTang <tangchunyou@icubecorp.cn> >>> --- >>> drivers/gpu/drm/panfrost/panfrost_job.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c >>> b/drivers/gpu/drm/panfrost/panfrost_job.c index >>> 6003cfeb1322..52bccc1d2d42 100644 --- >>> a/drivers/gpu/drm/panfrost/panfrost_job.c +++ >>> b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -281,7 +281,7 @@ >>> static void panfrost_job_cleanup(struct kref *ref) if >>> (job->mappings) { for (i = 0; i < job->bo_count; i++) { >>> if (!job->mappings[i]) >>> - break; >>> + continue; >>> >>> atomic_dec(&job->mappings[i]->obj->gpu_usecount); >>> panfrost_gem_mapping_put(job->mappings[i]); >>> > > ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] drm/panfrost:modify 'break' to 'continue' to traverse the circulation 2021-06-21 10:45 ` Steven Price @ 2021-06-22 1:31 ` Chunyou Tang 0 siblings, 0 replies; 7+ messages in thread From: Chunyou Tang @ 2021-06-22 1:31 UTC (permalink / raw) To: Steven Price Cc: tomeu.vizoso, airlied, linux-kernel, dri-devel, alyssa.rosenzweig, ChunyouTang [-- Warning: decoded text below may be mangled, UTF-8 assumed --] [-- Attachment #1: Type: text/plain; charset=GB18030, Size: 4305 bytes --] Hi Steve, I make a mistake about the code branch,I will test it later, thinks for your reply. Chunyou ÓÚ Mon, 21 Jun 2021 11:45:18 +0100 Steven Price <steven.price@arm.com> дµÀ: > On 19/06/2021 04:09, Chunyou Tang wrote: > > Hi Steve, > > 1, > > from > > https://lore.kernel.org/lkml/31644881-134a-2d6e-dddf-e658a3a8176b@arm.com/ > > I can see what your sent,I used a wrong email address,Now it > > correct. 2, > >>> Unless I'm mistaken the situation where some mappings may be NULL > >>> is caused by the loop in panfrost_lookup_bos() not completing > >>> successfully > >>> (panfrost_gem_mapping_get() returning NULL). In this case if > >>> mappings[i] > >>> is NULL then all following mappings must also be NULL. So 'break' > >>> allows > >>> us to skip the later ones. Admittedly the performance here isn't > >>> important so I'm not sure it's worth the optimisation, but AIUI > >>> this code isn't actually wrong. > > > > from panfrost_lookup_bos(),you can see: > > for (i = 0; i < job->bo_count; i++) { > > struct panfrost_gem_mapping *mapping; > > > > bo = to_panfrost_bo(job->bos[i]); > > ICUBE_DEBUG_PRINTK("panfrost bo gem handle=0x%x > > is_dumb=%d\n", bo->gem_handle, bo->is_dumb); > > if (!bo->is_dumb) { > > mapping = panfrost_gem_mapping_get(bo, priv); > > if (!mapping) { > > ret = -EINVAL; > > break; > > } > > > > atomic_inc(&bo->gpu_usecount); > > job->mappings[i] = mapping; > > } else { > > atomic_inc(&bo->gpu_usecount); > > job->mappings[i] = NULL; > > } > > } > > This code isn't upstream - in drm-misc/drm-misc-next (and all mainline > kernels from what I can tell) this doesn't have any "is_dumb" test. > Which branch are you using? > > > if bo->is_dumb is TRUE,the job->mappings[i] will set to NULL,and the > > while will be continue,so if job->mappings[i] is NULL,the following > > can not be NULL. > > I agree that with the above code the panfrost_job_cleanup() would need > changing. But we don't (currently) have this code upstream, so this > change doesn't make sense upstream. > > Thanks, > > Steve > > > 3, > > I've had this problem in our project,the value of is_dumb like > > these: 0 > > 0 > > 0 > > 1 > > 0 > > 0 > > 0 > > so,when job->mappings[i] is NULL,we can not break the while in > > panfrost_job_cleanup(). > > > > thanks > > Chunyou > > > > ÓÚ Fri, 18 Jun 2021 13:43:25 +0100 > > Steven Price <steven.price@arm.com> дµÀ: > > > >> On 17/06/2021 09:04, ChunyouTang wrote: > >>> From: ChunyouTang <tangchunyou@icubecorp.cn> > >>> > >>> The 'break' can cause 'Memory manager not clean during takedown' > >>> > >>> It cannot use break to finish the circulation,it should use > >>> > >>> continue to traverse the circulation.it should put every mapping > >>> > >>> which is not NULL. > >> > >> You don't appear to have answered my question about whether you've > >> actually seen this happen (and ideally what circumstances). In my > >> previous email[1] I explained why I don't think this is needed. You > >> need to convince me that I've overlooked something. > >> > >> Thanks, > >> > >> Steve > >> > >> [1] > >> https://lore.kernel.org/r/31644881-134a-2d6e-dddf-e658a3a8176b%40arm.com > >> > >>> Signed-off-by: ChunyouTang <tangchunyou@icubecorp.cn> > >>> --- > >>> drivers/gpu/drm/panfrost/panfrost_job.c | 2 +- > >>> 1 file changed, 1 insertion(+), 1 deletion(-) > >>> > >>> diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c > >>> b/drivers/gpu/drm/panfrost/panfrost_job.c index > >>> 6003cfeb1322..52bccc1d2d42 100644 --- > >>> a/drivers/gpu/drm/panfrost/panfrost_job.c +++ > >>> b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -281,7 +281,7 @@ > >>> static void panfrost_job_cleanup(struct kref *ref) if > >>> (job->mappings) { for (i = 0; i < job->bo_count; i++) { > >>> if (!job->mappings[i]) > >>> - break; > >>> + continue; > >>> > >>> atomic_dec(&job->mappings[i]->obj->gpu_usecount); > >>> panfrost_gem_mapping_put(job->mappings[i]); > >>> > > > > ^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2021-06-22 1:47 UTC | newest] Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2021-06-17 8:04 [PATCH] drm/panfrost:modify 'break' to 'continue' to traverse the circulation ChunyouTang 2021-06-17 8:04 ` ChunyouTang 2021-06-18 12:43 ` Steven Price 2021-06-19 3:09 ` Chunyou Tang 2021-06-19 3:09 ` Chunyou Tang 2021-06-21 10:45 ` Steven Price 2021-06-22 1:31 ` Chunyou Tang
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