linux-dev/drivers/gpu/drm/ttm/ttm_memory.c, branch linus/master

drm/ttm: move memory accounting into vmwgfx v4

2021-02-09T16:27:33Z

This is just another feature which is only used by VMWGFX, so move it into the driver instead. I've tried to add the accounting sysfs file to the kobject of the drm minor, but I'm not 100% sure if this works as expected. v2: fix typo in KFD and avoid 64bit divide v3: fix init order in VMWGFX v4: use pdev sysfs reference instead of drm Signed-off-by: Christian König Reviewed-by: Zack Rusin (v3) Tested-by: Nirmoy Das Link: https://patchwork.freedesktop.org/patch/msgid/20210208133226.36955-2-christian.koenig@amd.com

drm/ttm: rework ttm_tt page limit v4

2021-02-09T16:27:12Z

TTM implements a rather extensive accounting of allocated memory. There are two reasons for this: 1. It tries to block userspace allocating a huge number of very small BOs without accounting for the kmalloced memory. 2. Make sure we don't over allocate and run into an OOM situation during swapout while trying to handle the memory shortage. This is only partially a good idea. First of all it is perfectly valid for an application to use all of system memory, limiting it to 50% is not really acceptable. What we need to take care of is that the application is held accountable for the memory it allocated. This is what control mechanisms like memcg and the normal Linux page accounting already do. Making sure that we don't run into an OOM situation while trying to cope with a memory shortage is still a good idea, but this is also not very well implemented since it means another opportunity of recursion from the driver back into TTM. So start to rework all of this by implementing a shrinker callback which allows for TT object to be swapped out if necessary. v2: Switch from limit to shrinker callback. v3: fix gfp mask handling, use atomic for swapable_pages, add debugfs v4: drop the extra gfp_mask checks Signed-off-by: Christian König Reviewed-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20210208133226.36955-1-christian.koenig@amd.com

drm/ttm/drivers: remove unecessary ttm_module.h include v2

2020-12-01T16:43:46Z

ttm_module.h deals with internals of TTM and should never be include outside of it. v2: also move the file around Signed-off-by: Christian König Acked-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/404885/

drm/ttm: replace context flags with bools v2

2020-11-04T10:23:25Z

The ttm_operation_ctx structure has a mixture of flags and bools. Drop the flags and replace them with bools as well. v2: fix typos, improve comments Signed-off-by: Christian König Reviewed-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/398686/

drm/ttm: nuke old page allocator

2020-10-29T14:57:57Z

Not used any more. Signed-off-by: Christian König Reviewed-by: Dave Airlie Reviewed-by: Madhav Chauhan Tested-by: Huang Rui Link: https://patchwork.freedesktop.org/patch/397087/?series=83051&rev=1

drm/ttm: wire up the new pool as default one v2

2020-10-29T14:56:45Z

Provide the necessary parameters by all drivers and use the new pool alloc when no driver specific function is provided. v2: fix the GEM VRAM helpers Signed-off-by: Christian König Reviewed-by: Dave Airlie Reviewed-by: Madhav Chauhan Tested-by: Huang Rui Link: https://patchwork.freedesktop.org/patch/397081/?series=83051&rev=1

drm/ttm: new TT backend allocation pool v3

2020-10-29T14:52:51Z

This replaces the spaghetti code in the two existing page pools. First of all depending on the allocation size it is between 3 (1GiB) and 5 (1MiB) times faster than the old implementation. It makes better use of buddy pages to allow for larger physical contiguous allocations which should result in better TLB utilization at least for amdgpu. Instead of a completely braindead approach of filling the pool with one CPU while another one is trying to shrink it we only give back freed pages. This also results in much less locking contention and a trylock free MM shrinker callback, so we can guarantee that pages are given back to the system when needed. Downside of this is that it takes longer for many small allocations until the pool is filled up. We could address this, but I couldn't find an use case where this actually matters. We also don't bother freeing large chunks of pages any more since the CPU overhead in that path isn't really that important. The sysfs files are replaced with a single module parameter, allowing users to override how many pages should be globally pooled in TTM. This unfortunately breaks the UAPI slightly, but as far as we know nobody ever depended on this. Zeroing memory coming from the pool was handled inconsistently. The alloc_pages() based pool was zeroing it, the dma_alloc_attr() based one wasn't. For now the new implementation isn't zeroing pages from the pool either and only sets the __GFP_ZERO flag when necessary. The implementation has only 768 lines of code compared to the over 2600 of the old one, and also allows for saving quite a bunch of code in the drivers since we don't need specialized handling there any more based on kernel config. Additional to all of that there was a neat bug with IOMMU, coherent DMA mappings and huge pages which is now fixed in the new code as well. v2: make ttm_pool_apply_caching static as reported by the kernel bot, add some more checks v3: fix some more checkpatch.pl warnings Signed-off-by: Christian König Reviewed-by: Dave Airlie Reviewed-by: Madhav Chauhan Tested-by: Huang Rui Link: https://patchwork.freedesktop.org/patch/397080/?series=83051&rev=1

drm/ttm: drop glob parameter from ttm_bo_swapout

2020-10-07T11:53:38Z

We can always access the global state. Signed-off-by: Christian König Acked-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/393499/

drm/ttm: update kernel-doc line comments

2020-09-21T09:20:13Z

Update kernel-doc line comments to fix warnings reported by make W=1. drivers/gpu/drm/ttm/ttm_memory.c:271: warning: Function parameter or member 'glob' not described in 'ttm_shrink' drivers/gpu/drm/ttm/ttm_memory.c:271: warning: Function parameter or member 'from_wq' not described in 'ttm_shrink' drivers/gpu/drm/ttm/ttm_memory.c:271: warning: Function parameter or member 'extra' not described in 'ttm_shrink' drivers/gpu/drm/ttm/ttm_memory.c:271: warning: Function parameter or member 'ctx' not described in 'ttm_shrink' Signed-off-by: Tian Tao Reviewed-by: Christian König Acked-by: Huang Rui Link: https://patchwork.freedesktop.org/patch/391317/ Signed-off-by: Christian König

drm/ttm: some cleanups

2020-09-17T09:44:04Z

Unexport ttm_check_under_lowerlimit. Make ttm_bo_acc_size static and unexport it. Remove ttm_get_kernel_zone_memory_size. Signed-off-by: Christian König Reviewed-by: Dave Airlie Link: https://patchwork.freedesktop.org/patch/390515/