From 6f56103d7e95f96568a460493ff6c0ced45f538b Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Wed, 24 Jan 2018 11:36:07 +0000 Subject: [PATCH] drm/i915: Track the number of times we have woken the GPU up By counting the number of times we have woken up, we have a very simple means of defining an epoch, which will come in handy if we want to perform deferred tasks at the end of an epoch (i.e. while we are going to sleep) without imposing on the next activity cycle. v2: No reason to specify precise number of bits here. v3: Take Tvrtko's advice and reserve 0 as an invalid epoch. Signed-off-by: Chris Wilson Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20180124113608.14909-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_debugfs.c | 7 ++++--- drivers/gpu/drm/i915/i915_drv.h | 6 ++++++ drivers/gpu/drm/i915/i915_gem_request.c | 2 ++ 3 files changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 80dc679..3387352 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -2717,7 +2717,8 @@ static int i915_runtime_pm_status(struct seq_file *m, void *unused) if (!HAS_RUNTIME_PM(dev_priv)) seq_puts(m, "Runtime power management not supported\n"); - seq_printf(m, "GPU idle: %s\n", yesno(!dev_priv->gt.awake)); + seq_printf(m, "GPU idle: %s (epoch %u)\n", + yesno(!dev_priv->gt.awake), dev_priv->gt.epoch); seq_printf(m, "IRQs disabled: %s\n", yesno(!intel_irqs_enabled(dev_priv))); #ifdef CONFIG_PM @@ -3150,8 +3151,8 @@ static int i915_engine_info(struct seq_file *m, void *unused) intel_runtime_pm_get(dev_priv); - seq_printf(m, "GT awake? %s\n", - yesno(dev_priv->gt.awake)); + seq_printf(m, "GT awake? %s (epoch %u)\n", + yesno(dev_priv->gt.awake), dev_priv->gt.epoch); seq_printf(m, "Global active requests: %d\n", dev_priv->gt.active_requests); seq_printf(m, "CS timestamp frequency: %u kHz\n", diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index c707eee..1f9df28 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -2313,6 +2313,12 @@ struct drm_i915_private { bool awake; /** + * The number of times we have woken up. + */ + unsigned int epoch; +#define I915_EPOCH_INVALID 0 + + /** * We leave the user IRQ off as much as possible, * but this means that requests will finish and never * be retired once the system goes idle. Set a timer to diff --git a/drivers/gpu/drm/i915/i915_gem_request.c b/drivers/gpu/drm/i915/i915_gem_request.c index a0f451b..06ec27a6 100644 --- a/drivers/gpu/drm/i915/i915_gem_request.c +++ b/drivers/gpu/drm/i915/i915_gem_request.c @@ -274,6 +274,8 @@ static void mark_busy(struct drm_i915_private *i915) intel_display_power_get(i915, POWER_DOMAIN_GT_IRQ); i915->gt.awake = true; + if (unlikely(++i915->gt.epoch == 0)) /* keep 0 as invalid */ + i915->gt.epoch = 1; intel_enable_gt_powersave(i915); i915_update_gfx_val(i915); -- 2.7.4