| Message ID | 20180227115000.4105-4-christian.koenig@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi guys, at least on amdgpu and radeon the page array allocated by ttm_dma_tt_init is completely unused in the case of DMA-buf sharing. So I'm trying to get rid of that by only allocating the DMA address array. Now the only other user of DMA-buf together with ttm_dma_tt_init is Nouveau. So my question is are you guys using the page array anywhere in your kernel driver in case of a DMA-buf sharing? If no then I could just make this the default behavior for all drivers and save quite a bit of memory for everybody. Thanks, Christian. Am 27.02.2018 um 12:49 schrieb Christian König: > This allows drivers to only allocate dma addresses, but not a page > array. > > Signed-off-by: Christian König <christian.koenig@amd.com> > --- > drivers/gpu/drm/ttm/ttm_tt.c | 54 ++++++++++++++++++++++++++++++++++++-------- > include/drm/ttm/ttm_tt.h | 2 ++ > 2 files changed, 47 insertions(+), 9 deletions(-) > > diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c > index 8e0b525cda00..971133106ec2 100644 > --- a/drivers/gpu/drm/ttm/ttm_tt.c > +++ b/drivers/gpu/drm/ttm/ttm_tt.c > @@ -108,6 +108,16 @@ static int ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm) > return 0; > } > > +static int ttm_sg_tt_alloc_page_directory(struct ttm_dma_tt *ttm) > +{ > + ttm->dma_address = kvmalloc_array(ttm->ttm.num_pages, > + sizeof(*ttm->dma_address), > + GFP_KERNEL | __GFP_ZERO); > + if (!ttm->dma_address) > + return -ENOMEM; > + return 0; > +} > + > #ifdef CONFIG_X86 > static inline int ttm_tt_set_page_caching(struct page *p, > enum ttm_caching_state c_old, > @@ -227,8 +237,8 @@ void ttm_tt_destroy(struct ttm_tt *ttm) > ttm->func->destroy(ttm); > } > > -int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, > - unsigned long size, uint32_t page_flags) > +void ttm_tt_init_fields(struct ttm_tt *ttm, struct ttm_bo_device *bdev, > + unsigned long size, uint32_t page_flags) > { > ttm->bdev = bdev; > ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; > @@ -236,6 +246,12 @@ int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, > ttm->page_flags = page_flags; > ttm->state = tt_unpopulated; > ttm->swap_storage = NULL; > +} > + > +int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, > + unsigned long size, uint32_t page_flags) > +{ > + ttm_tt_init_fields(ttm, bdev, size, page_flags); > > if (ttm_tt_alloc_page_directory(ttm)) { > ttm_tt_destroy(ttm); > @@ -258,12 +274,7 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, > { > struct ttm_tt *ttm = &ttm_dma->ttm; > > - ttm->bdev = bdev; > - ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; > - ttm->caching_state = tt_cached; > - ttm->page_flags = page_flags; > - ttm->state = tt_unpopulated; > - ttm->swap_storage = NULL; > + ttm_tt_init_fields(ttm, bdev, size, page_flags); > > INIT_LIST_HEAD(&ttm_dma->pages_list); > if (ttm_dma_tt_alloc_page_directory(ttm_dma)) { > @@ -275,11 +286,36 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, > } > EXPORT_SYMBOL(ttm_dma_tt_init); > > +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, > + unsigned long size, uint32_t page_flags) > +{ > + struct ttm_tt *ttm = &ttm_dma->ttm; > + int ret; > + > + ttm_tt_init_fields(ttm, bdev, size, page_flags); > + > + INIT_LIST_HEAD(&ttm_dma->pages_list); > + if (page_flags & TTM_PAGE_FLAG_SG) > + ret = ttm_sg_tt_alloc_page_directory(ttm_dma); > + else > + ret = ttm_dma_tt_alloc_page_directory(ttm_dma); > + if (ret) { > + ttm_tt_destroy(ttm); > + pr_err("Failed allocating page table\n"); > + return -ENOMEM; > + } > + return 0; > +} > +EXPORT_SYMBOL(ttm_sg_tt_init); > + > void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma) > { > struct ttm_tt *ttm = &ttm_dma->ttm; > > - kvfree(ttm->pages); > + if (ttm->pages) > + kvfree(ttm->pages); > + else > + kvfree(ttm_dma->dma_address); > ttm->pages = NULL; > ttm_dma->dma_address = NULL; > } > diff --git a/include/drm/ttm/ttm_tt.h b/include/drm/ttm/ttm_tt.h > index 9c78556b488e..1cf316a4257c 100644 > --- a/include/drm/ttm/ttm_tt.h > +++ b/include/drm/ttm/ttm_tt.h > @@ -163,6 +163,8 @@ int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, > unsigned long size, uint32_t page_flags); > int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, > unsigned long size, uint32_t page_flags); > +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, > + unsigned long size, uint32_t page_flags); > > /** > * ttm_tt_fini
Ping? Am 27.02.2018 um 13:07 schrieb Christian König: > Hi guys, > > at least on amdgpu and radeon the page array allocated by > ttm_dma_tt_init is completely unused in the case of DMA-buf sharing. > So I'm trying to get rid of that by only allocating the DMA address > array. > > Now the only other user of DMA-buf together with ttm_dma_tt_init is > Nouveau. So my question is are you guys using the page array anywhere > in your kernel driver in case of a DMA-buf sharing? > > If no then I could just make this the default behavior for all drivers > and save quite a bit of memory for everybody. > > Thanks, > Christian. > > Am 27.02.2018 um 12:49 schrieb Christian König: >> This allows drivers to only allocate dma addresses, but not a page >> array. >> >> Signed-off-by: Christian König <christian.koenig@amd.com> >> --- >> drivers/gpu/drm/ttm/ttm_tt.c | 54 >> ++++++++++++++++++++++++++++++++++++-------- >> include/drm/ttm/ttm_tt.h | 2 ++ >> 2 files changed, 47 insertions(+), 9 deletions(-) >> >> diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c >> index 8e0b525cda00..971133106ec2 100644 >> --- a/drivers/gpu/drm/ttm/ttm_tt.c >> +++ b/drivers/gpu/drm/ttm/ttm_tt.c >> @@ -108,6 +108,16 @@ static int >> ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm) >> return 0; >> } >> +static int ttm_sg_tt_alloc_page_directory(struct ttm_dma_tt *ttm) >> +{ >> + ttm->dma_address = kvmalloc_array(ttm->ttm.num_pages, >> + sizeof(*ttm->dma_address), >> + GFP_KERNEL | __GFP_ZERO); >> + if (!ttm->dma_address) >> + return -ENOMEM; >> + return 0; >> +} >> + >> #ifdef CONFIG_X86 >> static inline int ttm_tt_set_page_caching(struct page *p, >> enum ttm_caching_state c_old, >> @@ -227,8 +237,8 @@ void ttm_tt_destroy(struct ttm_tt *ttm) >> ttm->func->destroy(ttm); >> } >> -int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, >> - unsigned long size, uint32_t page_flags) >> +void ttm_tt_init_fields(struct ttm_tt *ttm, struct ttm_bo_device *bdev, >> + unsigned long size, uint32_t page_flags) >> { >> ttm->bdev = bdev; >> ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; >> @@ -236,6 +246,12 @@ int ttm_tt_init(struct ttm_tt *ttm, struct >> ttm_bo_device *bdev, >> ttm->page_flags = page_flags; >> ttm->state = tt_unpopulated; >> ttm->swap_storage = NULL; >> +} >> + >> +int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, >> + unsigned long size, uint32_t page_flags) >> +{ >> + ttm_tt_init_fields(ttm, bdev, size, page_flags); >> if (ttm_tt_alloc_page_directory(ttm)) { >> ttm_tt_destroy(ttm); >> @@ -258,12 +274,7 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, >> struct ttm_bo_device *bdev, >> { >> struct ttm_tt *ttm = &ttm_dma->ttm; >> - ttm->bdev = bdev; >> - ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; >> - ttm->caching_state = tt_cached; >> - ttm->page_flags = page_flags; >> - ttm->state = tt_unpopulated; >> - ttm->swap_storage = NULL; >> + ttm_tt_init_fields(ttm, bdev, size, page_flags); >> INIT_LIST_HEAD(&ttm_dma->pages_list); >> if (ttm_dma_tt_alloc_page_directory(ttm_dma)) { >> @@ -275,11 +286,36 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, >> struct ttm_bo_device *bdev, >> } >> EXPORT_SYMBOL(ttm_dma_tt_init); >> +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct >> ttm_bo_device *bdev, >> + unsigned long size, uint32_t page_flags) >> +{ >> + struct ttm_tt *ttm = &ttm_dma->ttm; >> + int ret; >> + >> + ttm_tt_init_fields(ttm, bdev, size, page_flags); >> + >> + INIT_LIST_HEAD(&ttm_dma->pages_list); >> + if (page_flags & TTM_PAGE_FLAG_SG) >> + ret = ttm_sg_tt_alloc_page_directory(ttm_dma); >> + else >> + ret = ttm_dma_tt_alloc_page_directory(ttm_dma); >> + if (ret) { >> + ttm_tt_destroy(ttm); >> + pr_err("Failed allocating page table\n"); >> + return -ENOMEM; >> + } >> + return 0; >> +} >> +EXPORT_SYMBOL(ttm_sg_tt_init); >> + >> void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma) >> { >> struct ttm_tt *ttm = &ttm_dma->ttm; >> - kvfree(ttm->pages); >> + if (ttm->pages) >> + kvfree(ttm->pages); >> + else >> + kvfree(ttm_dma->dma_address); >> ttm->pages = NULL; >> ttm_dma->dma_address = NULL; >> } >> diff --git a/include/drm/ttm/ttm_tt.h b/include/drm/ttm/ttm_tt.h >> index 9c78556b488e..1cf316a4257c 100644 >> --- a/include/drm/ttm/ttm_tt.h >> +++ b/include/drm/ttm/ttm_tt.h >> @@ -163,6 +163,8 @@ int ttm_tt_init(struct ttm_tt *ttm, struct >> ttm_bo_device *bdev, >> unsigned long size, uint32_t page_flags); >> int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct >> ttm_bo_device *bdev, >> unsigned long size, uint32_t page_flags); >> +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device >> *bdev, >> + unsigned long size, uint32_t page_flags); >> /** >> * ttm_tt_fini >
On Mon, Mar 5, 2018 at 10:06 PM, Christian König <christian.koenig@amd.com> wrote: > Ping? On a quick look, it looks like both are used sometimes. I believe this had something to do with the addition of Tegra support, but I'll need some time to look into the details of why/how these things are used again. Ben. > > > Am 27.02.2018 um 13:07 schrieb Christian König: >> >> Hi guys, >> >> at least on amdgpu and radeon the page array allocated by ttm_dma_tt_init >> is completely unused in the case of DMA-buf sharing. So I'm trying to get >> rid of that by only allocating the DMA address array. >> >> Now the only other user of DMA-buf together with ttm_dma_tt_init is >> Nouveau. So my question is are you guys using the page array anywhere in >> your kernel driver in case of a DMA-buf sharing? >> >> If no then I could just make this the default behavior for all drivers and >> save quite a bit of memory for everybody. >> >> Thanks, >> Christian. >> >> Am 27.02.2018 um 12:49 schrieb Christian König: >>> >>> This allows drivers to only allocate dma addresses, but not a page >>> array. >>> >>> Signed-off-by: Christian König <christian.koenig@amd.com> >>> --- >>> drivers/gpu/drm/ttm/ttm_tt.c | 54 >>> ++++++++++++++++++++++++++++++++++++-------- >>> include/drm/ttm/ttm_tt.h | 2 ++ >>> 2 files changed, 47 insertions(+), 9 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c >>> index 8e0b525cda00..971133106ec2 100644 >>> --- a/drivers/gpu/drm/ttm/ttm_tt.c >>> +++ b/drivers/gpu/drm/ttm/ttm_tt.c >>> @@ -108,6 +108,16 @@ static int ttm_dma_tt_alloc_page_directory(struct >>> ttm_dma_tt *ttm) >>> return 0; >>> } >>> +static int ttm_sg_tt_alloc_page_directory(struct ttm_dma_tt *ttm) >>> +{ >>> + ttm->dma_address = kvmalloc_array(ttm->ttm.num_pages, >>> + sizeof(*ttm->dma_address), >>> + GFP_KERNEL | __GFP_ZERO); >>> + if (!ttm->dma_address) >>> + return -ENOMEM; >>> + return 0; >>> +} >>> + >>> #ifdef CONFIG_X86 >>> static inline int ttm_tt_set_page_caching(struct page *p, >>> enum ttm_caching_state c_old, >>> @@ -227,8 +237,8 @@ void ttm_tt_destroy(struct ttm_tt *ttm) >>> ttm->func->destroy(ttm); >>> } >>> -int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, >>> - unsigned long size, uint32_t page_flags) >>> +void ttm_tt_init_fields(struct ttm_tt *ttm, struct ttm_bo_device *bdev, >>> + unsigned long size, uint32_t page_flags) >>> { >>> ttm->bdev = bdev; >>> ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; >>> @@ -236,6 +246,12 @@ int ttm_tt_init(struct ttm_tt *ttm, struct >>> ttm_bo_device *bdev, >>> ttm->page_flags = page_flags; >>> ttm->state = tt_unpopulated; >>> ttm->swap_storage = NULL; >>> +} >>> + >>> +int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, >>> + unsigned long size, uint32_t page_flags) >>> +{ >>> + ttm_tt_init_fields(ttm, bdev, size, page_flags); >>> if (ttm_tt_alloc_page_directory(ttm)) { >>> ttm_tt_destroy(ttm); >>> @@ -258,12 +274,7 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, >>> struct ttm_bo_device *bdev, >>> { >>> struct ttm_tt *ttm = &ttm_dma->ttm; >>> - ttm->bdev = bdev; >>> - ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; >>> - ttm->caching_state = tt_cached; >>> - ttm->page_flags = page_flags; >>> - ttm->state = tt_unpopulated; >>> - ttm->swap_storage = NULL; >>> + ttm_tt_init_fields(ttm, bdev, size, page_flags); >>> INIT_LIST_HEAD(&ttm_dma->pages_list); >>> if (ttm_dma_tt_alloc_page_directory(ttm_dma)) { >>> @@ -275,11 +286,36 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, >>> struct ttm_bo_device *bdev, >>> } >>> EXPORT_SYMBOL(ttm_dma_tt_init); >>> +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device >>> *bdev, >>> + unsigned long size, uint32_t page_flags) >>> +{ >>> + struct ttm_tt *ttm = &ttm_dma->ttm; >>> + int ret; >>> + >>> + ttm_tt_init_fields(ttm, bdev, size, page_flags); >>> + >>> + INIT_LIST_HEAD(&ttm_dma->pages_list); >>> + if (page_flags & TTM_PAGE_FLAG_SG) >>> + ret = ttm_sg_tt_alloc_page_directory(ttm_dma); >>> + else >>> + ret = ttm_dma_tt_alloc_page_directory(ttm_dma); >>> + if (ret) { >>> + ttm_tt_destroy(ttm); >>> + pr_err("Failed allocating page table\n"); >>> + return -ENOMEM; >>> + } >>> + return 0; >>> +} >>> +EXPORT_SYMBOL(ttm_sg_tt_init); >>> + >>> void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma) >>> { >>> struct ttm_tt *ttm = &ttm_dma->ttm; >>> - kvfree(ttm->pages); >>> + if (ttm->pages) >>> + kvfree(ttm->pages); >>> + else >>> + kvfree(ttm_dma->dma_address); >>> ttm->pages = NULL; >>> ttm_dma->dma_address = NULL; >>> } >>> diff --git a/include/drm/ttm/ttm_tt.h b/include/drm/ttm/ttm_tt.h >>> index 9c78556b488e..1cf316a4257c 100644 >>> --- a/include/drm/ttm/ttm_tt.h >>> +++ b/include/drm/ttm/ttm_tt.h >>> @@ -163,6 +163,8 @@ int ttm_tt_init(struct ttm_tt *ttm, struct >>> ttm_bo_device *bdev, >>> unsigned long size, uint32_t page_flags); >>> int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device >>> *bdev, >>> unsigned long size, uint32_t page_flags); >>> +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device >>> *bdev, >>> + unsigned long size, uint32_t page_flags); >>> /** >>> * ttm_tt_fini >> >> >
Patch 1: Acked-by: Roger He <Hongbo.He@amd.com> Patch 2~5: Reviewed-by: Roger He <Hongbo.He@amd.com> -----Original Message----- From: dri-devel [mailto:dri-devel-bounces@lists.freedesktop.org] On Behalf Of Christian K?nig Sent: Monday, March 05, 2018 8:07 PM To: dri-devel@lists.freedesktop.org; amd-gfx@lists.freedesktop.org; Ben Skeggs <bskeggs@redhat.com>; Ilia Mirkin <imirkin@alum.mit.edu>; nouveau <nouveau@lists.freedesktop.org> Subject: Re: [PATCH 4/5] drm/ttm: add ttm_sg_tt_init Ping? Am 27.02.2018 um 13:07 schrieb Christian König: > Hi guys, > > at least on amdgpu and radeon the page array allocated by > ttm_dma_tt_init is completely unused in the case of DMA-buf sharing. > So I'm trying to get rid of that by only allocating the DMA address > array. > > Now the only other user of DMA-buf together with ttm_dma_tt_init is > Nouveau. So my question is are you guys using the page array anywhere > in your kernel driver in case of a DMA-buf sharing? > > If no then I could just make this the default behavior for all drivers > and save quite a bit of memory for everybody. > > Thanks, > Christian. > > Am 27.02.2018 um 12:49 schrieb Christian König: >> This allows drivers to only allocate dma addresses, but not a page >> array. >> >> Signed-off-by: Christian König <christian.koenig@amd.com> >> --- >> drivers/gpu/drm/ttm/ttm_tt.c | 54 >> ++++++++++++++++++++++++++++++++++++-------- >> include/drm/ttm/ttm_tt.h | 2 ++ >> 2 files changed, 47 insertions(+), 9 deletions(-) >> >> diff --git a/drivers/gpu/drm/ttm/ttm_tt.c >> b/drivers/gpu/drm/ttm/ttm_tt.c index 8e0b525cda00..971133106ec2 >> 100644 >> --- a/drivers/gpu/drm/ttm/ttm_tt.c >> +++ b/drivers/gpu/drm/ttm/ttm_tt.c >> @@ -108,6 +108,16 @@ static int >> ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm) >> return 0; >> } >> +static int ttm_sg_tt_alloc_page_directory(struct ttm_dma_tt *ttm) >> +{ >> + ttm->dma_address = kvmalloc_array(ttm->ttm.num_pages, >> + sizeof(*ttm->dma_address), >> + GFP_KERNEL | __GFP_ZERO); >> + if (!ttm->dma_address) >> + return -ENOMEM; >> + return 0; >> +} >> + >> #ifdef CONFIG_X86 >> static inline int ttm_tt_set_page_caching(struct page *p, >> enum ttm_caching_state c_old, @@ -227,8 >> +237,8 @@ void ttm_tt_destroy(struct ttm_tt *ttm) >> ttm->func->destroy(ttm); >> } >> -int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, >> - unsigned long size, uint32_t page_flags) >> +void ttm_tt_init_fields(struct ttm_tt *ttm, struct ttm_bo_device >> +*bdev, >> + unsigned long size, uint32_t page_flags) >> { >> ttm->bdev = bdev; >> ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; @@ >> -236,6 +246,12 @@ int ttm_tt_init(struct ttm_tt *ttm, struct >> ttm_bo_device *bdev, >> ttm->page_flags = page_flags; >> ttm->state = tt_unpopulated; >> ttm->swap_storage = NULL; >> +} >> + >> +int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, >> + unsigned long size, uint32_t page_flags) { >> + ttm_tt_init_fields(ttm, bdev, size, page_flags); >> if (ttm_tt_alloc_page_directory(ttm)) { >> ttm_tt_destroy(ttm); >> @@ -258,12 +274,7 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, >> struct ttm_bo_device *bdev, >> { >> struct ttm_tt *ttm = &ttm_dma->ttm; >> - ttm->bdev = bdev; >> - ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; >> - ttm->caching_state = tt_cached; >> - ttm->page_flags = page_flags; >> - ttm->state = tt_unpopulated; >> - ttm->swap_storage = NULL; >> + ttm_tt_init_fields(ttm, bdev, size, page_flags); >> INIT_LIST_HEAD(&ttm_dma->pages_list); >> if (ttm_dma_tt_alloc_page_directory(ttm_dma)) { @@ -275,11 >> +286,36 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct >> ttm_bo_device *bdev, >> } >> EXPORT_SYMBOL(ttm_dma_tt_init); >> +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct >> ttm_bo_device *bdev, >> + unsigned long size, uint32_t page_flags) { >> + struct ttm_tt *ttm = &ttm_dma->ttm; >> + int ret; >> + >> + ttm_tt_init_fields(ttm, bdev, size, page_flags); >> + >> + INIT_LIST_HEAD(&ttm_dma->pages_list); >> + if (page_flags & TTM_PAGE_FLAG_SG) >> + ret = ttm_sg_tt_alloc_page_directory(ttm_dma); >> + else >> + ret = ttm_dma_tt_alloc_page_directory(ttm_dma); >> + if (ret) { >> + ttm_tt_destroy(ttm); >> + pr_err("Failed allocating page table\n"); >> + return -ENOMEM; >> + } >> + return 0; >> +} >> +EXPORT_SYMBOL(ttm_sg_tt_init); >> + >> void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma) >> { >> struct ttm_tt *ttm = &ttm_dma->ttm; >> - kvfree(ttm->pages); >> + if (ttm->pages) >> + kvfree(ttm->pages); >> + else >> + kvfree(ttm_dma->dma_address); >> ttm->pages = NULL; >> ttm_dma->dma_address = NULL; >> } >> diff --git a/include/drm/ttm/ttm_tt.h b/include/drm/ttm/ttm_tt.h >> index 9c78556b488e..1cf316a4257c 100644 >> --- a/include/drm/ttm/ttm_tt.h >> +++ b/include/drm/ttm/ttm_tt.h >> @@ -163,6 +163,8 @@ int ttm_tt_init(struct ttm_tt *ttm, struct >> ttm_bo_device *bdev, >> unsigned long size, uint32_t page_flags); >> int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct >> ttm_bo_device *bdev, >> unsigned long size, uint32_t page_flags); >> +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device >> *bdev, >> + unsigned long size, uint32_t page_flags); >> /** >> * ttm_tt_fini > _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
On Tue, Feb 27, 2018 at 01:07:06PM +0100, Christian König wrote: > Hi guys, > > at least on amdgpu and radeon the page array allocated by ttm_dma_tt_init is > completely unused in the case of DMA-buf sharing. So I'm trying to get rid > of that by only allocating the DMA address array. > > Now the only other user of DMA-buf together with ttm_dma_tt_init is Nouveau. > So my question is are you guys using the page array anywhere in your kernel > driver in case of a DMA-buf sharing? > > If no then I could just make this the default behavior for all drivers and > save quite a bit of memory for everybody. +1 on teaching ttm to no longer look at the struct page * in the dma-buf sgt, but only the dma_buf address. If there's still some need for in-kernel cpu or userspace mmap access then imo ttm needs to be fixed to delegate all that to the right dma-buf interfaces. The ttm abstraction is already there, it's just not passed through. I don't pretend to now enough of the details to review this stuff :-) -Daniel > > Thanks, > Christian. > > Am 27.02.2018 um 12:49 schrieb Christian König: > > This allows drivers to only allocate dma addresses, but not a page > > array. > > > > Signed-off-by: Christian König <christian.koenig@amd.com> > > --- > > drivers/gpu/drm/ttm/ttm_tt.c | 54 ++++++++++++++++++++++++++++++++++++-------- > > include/drm/ttm/ttm_tt.h | 2 ++ > > 2 files changed, 47 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c > > index 8e0b525cda00..971133106ec2 100644 > > --- a/drivers/gpu/drm/ttm/ttm_tt.c > > +++ b/drivers/gpu/drm/ttm/ttm_tt.c > > @@ -108,6 +108,16 @@ static int ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm) > > return 0; > > } > > +static int ttm_sg_tt_alloc_page_directory(struct ttm_dma_tt *ttm) > > +{ > > + ttm->dma_address = kvmalloc_array(ttm->ttm.num_pages, > > + sizeof(*ttm->dma_address), > > + GFP_KERNEL | __GFP_ZERO); > > + if (!ttm->dma_address) > > + return -ENOMEM; > > + return 0; > > +} > > + > > #ifdef CONFIG_X86 > > static inline int ttm_tt_set_page_caching(struct page *p, > > enum ttm_caching_state c_old, > > @@ -227,8 +237,8 @@ void ttm_tt_destroy(struct ttm_tt *ttm) > > ttm->func->destroy(ttm); > > } > > -int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, > > - unsigned long size, uint32_t page_flags) > > +void ttm_tt_init_fields(struct ttm_tt *ttm, struct ttm_bo_device *bdev, > > + unsigned long size, uint32_t page_flags) > > { > > ttm->bdev = bdev; > > ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; > > @@ -236,6 +246,12 @@ int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, > > ttm->page_flags = page_flags; > > ttm->state = tt_unpopulated; > > ttm->swap_storage = NULL; > > +} > > + > > +int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, > > + unsigned long size, uint32_t page_flags) > > +{ > > + ttm_tt_init_fields(ttm, bdev, size, page_flags); > > if (ttm_tt_alloc_page_directory(ttm)) { > > ttm_tt_destroy(ttm); > > @@ -258,12 +274,7 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, > > { > > struct ttm_tt *ttm = &ttm_dma->ttm; > > - ttm->bdev = bdev; > > - ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; > > - ttm->caching_state = tt_cached; > > - ttm->page_flags = page_flags; > > - ttm->state = tt_unpopulated; > > - ttm->swap_storage = NULL; > > + ttm_tt_init_fields(ttm, bdev, size, page_flags); > > INIT_LIST_HEAD(&ttm_dma->pages_list); > > if (ttm_dma_tt_alloc_page_directory(ttm_dma)) { > > @@ -275,11 +286,36 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, > > } > > EXPORT_SYMBOL(ttm_dma_tt_init); > > +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, > > + unsigned long size, uint32_t page_flags) > > +{ > > + struct ttm_tt *ttm = &ttm_dma->ttm; > > + int ret; > > + > > + ttm_tt_init_fields(ttm, bdev, size, page_flags); > > + > > + INIT_LIST_HEAD(&ttm_dma->pages_list); > > + if (page_flags & TTM_PAGE_FLAG_SG) > > + ret = ttm_sg_tt_alloc_page_directory(ttm_dma); > > + else > > + ret = ttm_dma_tt_alloc_page_directory(ttm_dma); > > + if (ret) { > > + ttm_tt_destroy(ttm); > > + pr_err("Failed allocating page table\n"); > > + return -ENOMEM; > > + } > > + return 0; > > +} > > +EXPORT_SYMBOL(ttm_sg_tt_init); > > + > > void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma) > > { > > struct ttm_tt *ttm = &ttm_dma->ttm; > > - kvfree(ttm->pages); > > + if (ttm->pages) > > + kvfree(ttm->pages); > > + else > > + kvfree(ttm_dma->dma_address); > > ttm->pages = NULL; > > ttm_dma->dma_address = NULL; > > } > > diff --git a/include/drm/ttm/ttm_tt.h b/include/drm/ttm/ttm_tt.h > > index 9c78556b488e..1cf316a4257c 100644 > > --- a/include/drm/ttm/ttm_tt.h > > +++ b/include/drm/ttm/ttm_tt.h > > @@ -163,6 +163,8 @@ int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, > > unsigned long size, uint32_t page_flags); > > int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, > > unsigned long size, uint32_t page_flags); > > +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, > > + unsigned long size, uint32_t page_flags); > > /** > > * ttm_tt_fini > > _______________________________________________ > Nouveau mailing list > Nouveau@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/nouveau
diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c index 8e0b525cda00..971133106ec2 100644 --- a/drivers/gpu/drm/ttm/ttm_tt.c +++ b/drivers/gpu/drm/ttm/ttm_tt.c @@ -108,6 +108,16 @@ static int ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm) return 0; } +static int ttm_sg_tt_alloc_page_directory(struct ttm_dma_tt *ttm) +{ + ttm->dma_address = kvmalloc_array(ttm->ttm.num_pages, + sizeof(*ttm->dma_address), + GFP_KERNEL | __GFP_ZERO); + if (!ttm->dma_address) + return -ENOMEM; + return 0; +} + #ifdef CONFIG_X86 static inline int ttm_tt_set_page_caching(struct page *p, enum ttm_caching_state c_old, @@ -227,8 +237,8 @@ void ttm_tt_destroy(struct ttm_tt *ttm) ttm->func->destroy(ttm); } -int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, - unsigned long size, uint32_t page_flags) +void ttm_tt_init_fields(struct ttm_tt *ttm, struct ttm_bo_device *bdev, + unsigned long size, uint32_t page_flags) { ttm->bdev = bdev; ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; @@ -236,6 +246,12 @@ int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, ttm->page_flags = page_flags; ttm->state = tt_unpopulated; ttm->swap_storage = NULL; +} + +int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, + unsigned long size, uint32_t page_flags) +{ + ttm_tt_init_fields(ttm, bdev, size, page_flags); if (ttm_tt_alloc_page_directory(ttm)) { ttm_tt_destroy(ttm); @@ -258,12 +274,7 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, { struct ttm_tt *ttm = &ttm_dma->ttm; - ttm->bdev = bdev; - ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; - ttm->caching_state = tt_cached; - ttm->page_flags = page_flags; - ttm->state = tt_unpopulated; - ttm->swap_storage = NULL; + ttm_tt_init_fields(ttm, bdev, size, page_flags); INIT_LIST_HEAD(&ttm_dma->pages_list); if (ttm_dma_tt_alloc_page_directory(ttm_dma)) { @@ -275,11 +286,36 @@ int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, } EXPORT_SYMBOL(ttm_dma_tt_init); +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, + unsigned long size, uint32_t page_flags) +{ + struct ttm_tt *ttm = &ttm_dma->ttm; + int ret; + + ttm_tt_init_fields(ttm, bdev, size, page_flags); + + INIT_LIST_HEAD(&ttm_dma->pages_list); + if (page_flags & TTM_PAGE_FLAG_SG) + ret = ttm_sg_tt_alloc_page_directory(ttm_dma); + else + ret = ttm_dma_tt_alloc_page_directory(ttm_dma); + if (ret) { + ttm_tt_destroy(ttm); + pr_err("Failed allocating page table\n"); + return -ENOMEM; + } + return 0; +} +EXPORT_SYMBOL(ttm_sg_tt_init); + void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma) { struct ttm_tt *ttm = &ttm_dma->ttm; - kvfree(ttm->pages); + if (ttm->pages) + kvfree(ttm->pages); + else + kvfree(ttm_dma->dma_address); ttm->pages = NULL; ttm_dma->dma_address = NULL; } diff --git a/include/drm/ttm/ttm_tt.h b/include/drm/ttm/ttm_tt.h index 9c78556b488e..1cf316a4257c 100644 --- a/include/drm/ttm/ttm_tt.h +++ b/include/drm/ttm/ttm_tt.h @@ -163,6 +163,8 @@ int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, unsigned long size, uint32_t page_flags); int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, unsigned long size, uint32_t page_flags); +int ttm_sg_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, + unsigned long size, uint32_t page_flags); /** * ttm_tt_fini
This allows drivers to only allocate dma addresses, but not a page array. Signed-off-by: Christian König <christian.koenig@amd.com> --- drivers/gpu/drm/ttm/ttm_tt.c | 54 ++++++++++++++++++++++++++++++++++++-------- include/drm/ttm/ttm_tt.h | 2 ++ 2 files changed, 47 insertions(+), 9 deletions(-)