Nice work, but a few comments. First of all you need to reorder the patches. Adding the exceptions to the restrictions should come first, then the restriction itself. Otherwise we might break a setup in between the patches and that is bad for bisecting. Then make all values configurable, e.g. take a closer look at ttm_memory.c. Just add attributes directly under the memory_accounting directory (see ttm_mem_global_init). Additional to that you can't put device specific information (the no_retry flag) into ttm_mem_global, that is driver unspecific and won't work like this. Move the new call out of ttm_mem_global_reserve() and into ttm_page_alloc.c or ttm_page_alloc_dma.c (but keep it in ttm_memory.c). ttm_mem_global_reserve() is called for each page allocated and si_mem_available() is a bit to heavy for that. Maybe name TTM_OPT_FLAG_ALLOW_ALLOC_ANYWAY something like _FORCE_ALLOCATION or _ALLOW_OOM. And please also try if a criteria like (si_mem_available() + get_nr_swap_pages()) < limit works as well. This way we would have only a single new limit. Regards, Christian. Am 06.02.2018 um 10:04 schrieb Roger He: > currently ttm code has no any allocation limit. So it allows pages > allocatation unlimited until OOM. Because if swap space is full > of swapped pages and then system memory will be filled up with ttm > pages. and then any memory allocation request will trigger OOM. > > > the following patches is for prevent OOM triggered by TTM. > the basic idea is when allocating TTM pages, check the free swap space > firt. if it is less than the fixe limit, reject the allocation request. > but there are two exceptions which should allow it regardless of zone > memory account limit. > a. page fault > for ttm_mem_global_reserve if serving for page fault routine, > because page fault routing already grabbed system memory so the > allowance of this exception is harmless. Otherwise, it will trigger > OOM killer. > b. suspend > anyway, we should allow suspend success always. > > > at last, if bdev.no_retry is false (by defaut), keep the original behavior > no any change. > > Roger He (5): > drm/ttm: check if the free swap space is under limit 256MB > drm/ttm: keep original behavior except with flag no_retry > drm/ttm: use bit flag to replace allow_reserved_eviction in > ttm_operation_ctx > drm/ttm: add bit flag TTM_OPT_FLAG_ALLOW_ALLOC_ANYWAY > drm/ttm: add input parameter allow_allo_anyway for ttm_bo_evict_mm > > drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 4 +-- > drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 2 +- > drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 4 +-- > drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 10 +++--- > drivers/gpu/drm/amd/amdgpu/amdgpu_object.h | 2 +- > drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 8 +++-- > drivers/gpu/drm/nouveau/nouveau_drm.c | 2 +- > drivers/gpu/drm/qxl/qxl_object.c | 4 +-- > drivers/gpu/drm/radeon/radeon_device.c | 6 ++-- > drivers/gpu/drm/radeon/radeon_object.c | 6 ++-- > drivers/gpu/drm/radeon/radeon_object.h | 3 +- > drivers/gpu/drm/ttm/ttm_bo.c | 19 +++++++---- > drivers/gpu/drm/ttm/ttm_bo_vm.c | 6 ++-- > drivers/gpu/drm/ttm/ttm_memory.c | 51 ++++++++++++++++++++++++++--- > drivers/gpu/drm/ttm/ttm_page_alloc_dma.c | 1 - > drivers/gpu/drm/vmwgfx/vmwgfx_drv.c | 6 ++-- > include/drm/ttm/ttm_bo_api.h | 14 ++++++-- > include/drm/ttm/ttm_memory.h | 6 ++++ > 18 files changed, 111 insertions(+), 43 deletions(-) >
