Sean Paul d4da4e3334 drm: Measure Self Refresh Entry/Exit times to avoid thrashing ... Currently the self refresh idle timer is a const set by the crtc. This is fine if the self refresh entry/exit times are well-known for all panels used on that crtc. However panels and workloads can vary quite a bit, and a timeout which works well for one doesn't work well for another. In the extreme, if the timeout is too short we could get in a situation where the self refresh exits are taking so long we queue up a self refresh entry before the exit commit is even finished. This patch changes the idle timeout to a moving average of the entry times + a moving average of exit times + the crtc constant. This patch was tested on rockchip, with a kevin CrOS panel the idle delay averages out to about ~235ms (35 entry + 100 exit + 100 const). On the same board, the bob panel idle delay lands around ~340ms (90 entry + 150 exit + 100 const). WRT the dedicated mutex in self_refresh_data, it would be nice if we could rely on drm_crtc.mutex to protect the average times, but there are a few reasons why a separate lock is a better choice: - We can't rely on drm_crtc.mutex being held if we're doing a nonblocking commit - We can't grab drm_crtc.mutex since drm_modeset_lock() doesn't tell us whether the lock was already held in the acquire context (it eats -EALREADY), so we can't tell if we should drop it or not - We don't need such a heavy-handed lock for what we're trying to do, commit ordering doesn't matter, so a point-of-use lock will be less contentious Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Sean Paul <seanpaul@chromium.org> Link to v1: https://patchwork.freedesktop.org/patch/msgid/20190917200443.64481-2-sean@poorly.run Link: https://patchwork.freedesktop.org/patch/msgid/20190918200734.149876-2-sean@poorly.run Changes in v2: - Migrate locking explanation from comment to commit msg (Daniel) - Turf constant entry delay and multiply the avg times by 2 (Daniel)		2019-09-19 10:03:32 -04:00
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bridge
i2c
ttm
amd_asic_type.h
ati_pcigart.h
drm_agpsupport.h
drm_atomic_helper.h
drm_atomic_state_helper.h
drm_atomic_uapi.h
drm_atomic.h
drm_audio_component.h
drm_auth.h
drm_blend.h
drm_bridge.h
drm_cache.h
drm_client.h
drm_color_mgmt.h
drm_connector.h
drm_crtc_helper.h
drm_crtc.h	drm: Fix kerneldoc and remove unused struct member in self_refresh helper	2019-09-19 10:03:19 -04:00
drm_damage_helper.h
drm_debugfs_crc.h
drm_debugfs.h
drm_device.h
drm_displayid.h
drm_dp_dual_mode_helper.h
drm_dp_helper.h
drm_dp_mst_helper.h
drm_drv.h
drm_dsc.h
drm_edid.h
drm_encoder_slave.h
drm_encoder.h
drm_fb_cma_helper.h
drm_fb_helper.h
drm_file.h
drm_fixed.h
drm_flip_work.h
drm_format_helper.h
drm_fourcc.h
drm_framebuffer.h
drm_gem_cma_helper.h
drm_gem_framebuffer_helper.h
drm_gem_shmem_helper.h
drm_gem_vram_helper.h
drm_gem.h
drm_hashtab.h
drm_hdcp.h
drm_ioctl.h
drm_irq.h
drm_lease.h
drm_legacy.h
drm_mipi_dbi.h
drm_mipi_dsi.h
drm_mm.h
drm_mode_config.h
drm_mode_object.h
drm_modes.h
drm_modeset_helper_vtables.h
drm_modeset_helper.h
drm_modeset_lock.h
drm_of.h
drm_os_linux.h
drm_panel.h
drm_pci.h
drm_pciids.h
drm_plane_helper.h
drm_plane.h
drm_prime.h
drm_print.h
drm_probe_helper.h
drm_property.h
drm_rect.h
drm_scdc_helper.h
drm_self_refresh_helper.h	drm: Measure Self Refresh Entry/Exit times to avoid thrashing	2019-09-19 10:03:32 -04:00
drm_simple_kms_helper.h
drm_syncobj.h
drm_sysfs.h
drm_util.h
drm_utils.h
drm_vblank.h
drm_vma_manager.h
drm_vram_mm_helper.h
drm_writeback.h
drmP.h
gma_drm.h
gpu_scheduler.h
i915_component.h
i915_drm.h
i915_mei_hdcp_interface.h
i915_pciids.h
intel_lpe_audio.h
intel-gtt.h
spsc_queue.h