This series introduces support for big and super pages in V3D. The V3D MMU has support for 64KB and 1MB pages, called big pages and super pages, which are currently not used. Therefore, this patchset has the intention to enable big and super pages in V3D. The advantage of enabling big and super pages is that if any entry for a page within a big/super page is cached in the MMU, it will be used for the translation of all virtual addresses in the range of that super page without requiring fetching any other entries.
Big/Super pages essentially mean a slightly better performance for users, especially in applications with high memory requirements (e.g. applications that use multiple large BOs). Using a Raspberry Pi 4 (with a PAGE_SIZE=4KB downstream kernel), when running traces from multiple applications, we were able to see the following improvements: fps_avg helped: warzone2100.70secs.1024x768.trace: 1.98 -> 2.42 (22.19%) fps_avg helped: warzone2100.30secs.1024x768.trace: 2 -> 2.45 (21.96%) fps_avg helped: supertuxkart-menus_1024x768.trace: 123.12 -> 128.39 (4.28%) fps_avg helped: vkQuake_capture_frames_1_through_1200_1280x720.gfxr: 61.26 -> 62.89 (2.67%) fps_avg helped: quake2-gles3-1280x720.trace: 63.42 -> 64.86 (2.27%) fps_avg helped: ue4_sun_temple_640x480.gfxr: 25.15 -> 25.63 (1.89%) fps_avg helped: ue4_shooter_game_high_quality_640x480.gfxr: 19.28 -> 19.61 (1.72%) fps_avg helped: ue4_shooter_game_shooting_high_quality_640x480.gfxr: 23.58 -> 23.91 (1.39%) fps_avg helped: quake3e_capture_frames_1_through_1800_1920x1080.gfxr: 61.40 -> 62.00 (0.96%) fps_avg helped: serious_sam_trace02_1280x720.gfxr: 49.41 -> 49.84 (0.86%) fps_avg helped: supertuxkart-racing_1024x768.trace: 8.69 -> 8.74 (0.56%) fps_avg helped: sponza_demo01_800x600.gfxr: 17.55 -> 17.64 (0.50%) fps_avg helped: quake2-gl1.4-1280x720.trace: 36.43 -> 36.58 (0.43%) fps_avg helped: quake3e-1280x720.trace: 94.49 -> 94.87 (0.40%) fps_avg helped: sponza_demo02_800x600.gfxr: 19.79 -> 19.87 (0.39%) Using a Raspberry Pi 5 (with a PAGE_SIZE=16KB downstream kernel), when running traces from multiple applications, we were able to see the following improvements: fps_avg helped: warzone2100.30secs.1024x768.trace: 4.40 -> 4.95 (12.58%) fps_avg helped: vkQuake_capture_frames_1_through_1200_1280x720.gfxr: 135.05 -> 141.21 (4.56%) fps_avg helped: supertuxkart-menus_1024x768.trace: 291.73 -> 302.05 (3.54%) fps_avg helped: quake2-gles3-1280x720.trace: 148.90 -> 153.57 (3.13%) fps_avg helped: quake2-gl1.4-1280x720.trace: 82.60 -> 84.46 (2.25%) fps_avg helped: ue4_shooter_game_shooting_low_quality_640x480.gfxr: 49.59 -> 50.54 (1.92%) fps_avg helped: ue4_shooter_game_shooting_high_quality_640x480.gfxr: 51.03 -> 51.93 (1.76%) fps_avg helped: ue4_shooter_game_high_quality_640x480.gfxr: 31.15 -> 31.64 (1.60%) fps_avg helped: ue4_sun_temple_640x480.gfxr: 40.26 -> 40.88 (1.54%) fps_avg helped: sponza_demo01_800x600.gfxr: 43.23 -> 43.84 (1.40%) fps_avg helped: warzone2100.70secs.1024x768.trace: 4.36 -> 4.42 (1.39%) fps_avg helped: sponza_demo02_800x600.gfxr: 48.94 -> 49.51 (1.17%) fps_avg helped: quake3e_capture_frames_1_through_1800_1920x1080.gfxr: 162.11 -> 163.13 (0.63%) fps_avg helped: quake3e-1280x720.trace: 229.82 -> 231.00 (0.51%) fps_avg helped: supertuxkart-racing_1024x768.trace: 20.42 -> 20.48 (0.30%) fps_avg helped: quake3e_capture_frames_1800_through_2400_1920x1080.gfxr: 157.45 -> 157.61 (0.10%) fps_avg helped: serious_sam_trace02_1280x720.gfxr: 59.99 -> 60.02 (0.05%) This series also introduces changes in the GEM helpers, in order to enable V3D to have a separate mount point for shmfs GEM objects. Any feedback from the community about the changes in the GEM helpers is welcomed! v1 -> v2: https://lore.kernel.org/dri-devel/20240311100959.205545-1-mca...@igalia.com/ * [1/6] Add Iago's R-b to PATCH 1/5 (Iago Toral) * [2/6] Create a new function `drm_gem_object_init_with_mnt()` to define the shmfs mountpoint. Now, we don't touch a bunch of drivers, as `drm_gem_object_init()` preserves its signature. (Tvrtko Ursulin) * [3/6] Use `huge=within_size` instead of `huge=always`, in order to avoid OOM. This also allow us to move away from the 2MB hack. (Tvrtko Ursulin) * [3/6] Add Iago's R-b to PATCH 3/5 (Iago Toral) * [5/6] Create a separate patch to reduce the alignment of the node allocation. (Iago Toral) * [6/6] Complete refactoring to the way that we iterate through the memory. (Tvrtko Ursulin) * [6/6] Don't use drm_prime_get_contiguous_size(), as it could give us misleading data. (Tvrtko Ursulin) * [6/6] Use both Big Pages (64K) and Super Pages (1MB). v2 -> v3: https://lore.kernel.org/dri-devel/20240405201753.1176914-1-mca...@igalia.com/T/ * [2/8] Add Tvrtko's R-b to PATCH 2/8 (Tvrtko Ursulin) * [4/8] Add Tvrtko's R-b to PATCH 4/8 (Tvrtko Ursulin) * [6/8] Now, PATCH 6/8 only adds support to big/super pages when writing out PTEs. BO creation with THP and addition of modparam are moved to other patches. (Tvrtko Ursulin) * [6/8] s/page_address/pfn (Tvrtko Ursulin) * [6/8] As `sg_dma_len()` returns `unsigned int`, then `len` must be `unsigned int` too. (Tvrtko Ursulin) * [6/8] `i` and `page_size` are `unsigned int` as well. (Tvrtko Ursulin) * [6/8] Move `i`, `page_prot` and `page_size` to the inner scope. (Tvrtko Ursulin) * [6/8] s/pte/page_address/ (Tvrtko Ursulin) * [7/8] New patch: Use gemfs/THP in BO creation if available (Tvrtko Ursulin) * [8/8] New patch: Add modparam for turning off Big/Super Pages (Tvrtko Ursulin) * [8/8] Don't expose the modparam `super_pages` unless CONFIG_TRANSPARENT_HUGEPAGE is enabled. (Tvrtko Ursulin) * [8/8] Use `v3d->gemfs` to check if the user disabled Super Pages support. (Tvrtko Ursulin) Best Regards, - Maíra Maíra Canal (8): drm/v3d: Fix return if scheduler initialization fails drm/gem: Create a drm_gem_object_init_with_mnt() function drm/v3d: Introduce gemfs drm/gem: Create shmem GEM object in a given mountpoint drm/v3d: Reduce the alignment of the node allocation drm/v3d: Support Big/Super Pages when writing out PTEs drm/v3d: Use gemfs/THP in BO creation if available drm/v3d: Add modparam for turning off Big/Super Pages drivers/gpu/drm/drm_gem.c | 34 +++++++++++++++-- drivers/gpu/drm/drm_gem_shmem_helper.c | 30 +++++++++++++-- drivers/gpu/drm/v3d/Makefile | 3 +- drivers/gpu/drm/v3d/v3d_bo.c | 21 ++++++++++- drivers/gpu/drm/v3d/v3d_drv.c | 8 ++++ drivers/gpu/drm/v3d/v3d_drv.h | 12 +++++- drivers/gpu/drm/v3d/v3d_gem.c | 6 ++- drivers/gpu/drm/v3d/v3d_gemfs.c | 51 +++++++++++++++++++++++++ drivers/gpu/drm/v3d/v3d_mmu.c | 52 +++++++++++++++++++------- include/drm/drm_gem.h | 3 ++ include/drm/drm_gem_shmem_helper.h | 3 ++ 11 files changed, 196 insertions(+), 27 deletions(-) create mode 100644 drivers/gpu/drm/v3d/v3d_gemfs.c -- 2.44.0