Everytime we take a wakeref, record the stack trace of where it was taken; clearing the set if we ever drop back to no owners. For debugging a rpm leak, we can look at all the current wakerefs and check if they have a matching rpm_put. Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/Kconfig.debug | 2 +- drivers/gpu/drm/i915/i915_debugfs.c | 6 + drivers/gpu/drm/i915/i915_drv.c | 8 +- drivers/gpu/drm/i915/i915_drv.h | 7 + drivers/gpu/drm/i915/intel_drv.h | 44 ++- drivers/gpu/drm/i915/intel_runtime_pm.c | 267 ++++++++++++++++-- .../gpu/drm/i915/selftests/mock_gem_device.c | 8 +- 7 files changed, 292 insertions(+), 50 deletions(-) diff --git a/drivers/gpu/drm/i915/Kconfig.debug b/drivers/gpu/drm/i915/Kconfig.debug index 9e36ffb5eb7c..a97929c47466 100644 --- a/drivers/gpu/drm/i915/Kconfig.debug +++ b/drivers/gpu/drm/i915/Kconfig.debug @@ -21,11 +21,11 @@ config DRM_I915_DEBUG select DEBUG_FS select PREEMPT_COUNT select I2C_CHARDEV + select STACKDEPOT select DRM_DP_AUX_CHARDEV select X86_MSR # used by igt/pm_rpm select DRM_VGEM # used by igt/prime_vgem (dmabuf interop checks) select DRM_DEBUG_MM if DRM=y - select STACKDEPOT if DRM=y # for DRM_DEBUG_MM select DRM_DEBUG_SELFTEST select SW_SYNC # signaling validation framework (igt/syncobj*) select DRM_I915_SW_FENCE_DEBUG_OBJECTS diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 39f319c49def..6d2e1cc61906 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -2699,6 +2699,12 @@ static int i915_runtime_pm_status(struct seq_file *m, void *unused) pci_power_name(pdev->current_state), pdev->current_state); + if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM)) { + struct drm_printer p = drm_seq_file_printer(m); + + print_intel_runtime_pm_wakeref(dev_priv, &p); + } + return 0; } diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 5dd7fc582e6f..5b1bf78ced59 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -895,6 +895,7 @@ static int i915_driver_init_early(struct drm_i915_private *dev_priv) mutex_init(&dev_priv->pps_mutex); i915_memcpy_init_early(dev_priv); + intel_runtime_pm_init_early(dev_priv); ret = i915_workqueues_init(dev_priv); if (ret < 0) @@ -1489,8 +1490,7 @@ void i915_driver_unload(struct drm_device *dev) i915_driver_cleanup_mmio(dev_priv); enable_rpm_wakeref_asserts(dev_priv); - - WARN_ON(atomic_read(&dev_priv->runtime_pm.wakeref_count)); + intel_runtime_pm_cleanup(dev_priv); } static void i915_driver_release(struct drm_device *dev) @@ -1694,6 +1694,8 @@ static int i915_drm_suspend_late(struct drm_device *dev, bool hibernation) out: enable_rpm_wakeref_asserts(dev_priv); + if (!dev_priv->uncore.user_forcewake.count) + intel_runtime_pm_cleanup(dev_priv); return ret; } @@ -2648,7 +2650,7 @@ static int intel_runtime_suspend(struct device *kdev) } enable_rpm_wakeref_asserts(dev_priv); - WARN_ON_ONCE(atomic_read(&dev_priv->runtime_pm.wakeref_count)); + intel_runtime_pm_cleanup(dev_priv); if (intel_uncore_arm_unclaimed_mmio_detection(dev_priv)) DRM_ERROR("Unclaimed access detected prior to suspending\n"); diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 5c833a45682d..11879d5c764d 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -45,6 +45,7 @@ #include <linux/pm_qos.h> #include <linux/reservation.h> #include <linux/shmem_fs.h> +#include <linux/stackdepot.h> #include <drm/drmP.h> #include <drm/intel-gtt.h> @@ -1288,6 +1289,12 @@ struct i915_runtime_pm { atomic_t wakeref_count; bool suspended; bool irqs_enabled; + +#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM) + spinlock_t debug_lock; + depot_stack_handle_t *debug_owners; + unsigned long debug_count; +#endif }; enum intel_pipe_crc_source { diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index f5731215210a..6d64f78f821d 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -41,6 +41,8 @@ #include <drm/drm_atomic.h> #include <media/cec-notifier.h> +struct drm_printer; + /** * __wait_for - magic wait macro * @@ -1958,6 +1960,7 @@ int intel_psr_wait_for_idle(const struct intel_crtc_state *new_crtc_state, u32 *out_value); /* intel_runtime_pm.c */ +void intel_runtime_pm_init_early(struct drm_i915_private *dev_priv); int intel_power_domains_init(struct drm_i915_private *); void intel_power_domains_cleanup(struct drm_i915_private *dev_priv); void intel_power_domains_init_hw(struct drm_i915_private *dev_priv, bool resume); @@ -1978,6 +1981,7 @@ void bxt_display_core_init(struct drm_i915_private *dev_priv, bool resume); void bxt_display_core_uninit(struct drm_i915_private *dev_priv); void intel_runtime_pm_enable(struct drm_i915_private *dev_priv); void intel_runtime_pm_disable(struct drm_i915_private *dev_priv); +void intel_runtime_pm_cleanup(struct drm_i915_private *dev_priv); const char * intel_display_power_domain_str(enum intel_display_power_domain domain); @@ -1995,23 +1999,23 @@ void icl_dbuf_slices_update(struct drm_i915_private *dev_priv, u8 req_slices); static inline void -assert_rpm_device_not_suspended(struct drm_i915_private *dev_priv) +assert_rpm_device_not_suspended(struct drm_i915_private *i915) { - WARN_ONCE(dev_priv->runtime_pm.suspended, + WARN_ONCE(i915->runtime_pm.suspended, "Device suspended during HW access\n"); } static inline void -assert_rpm_wakelock_held(struct drm_i915_private *dev_priv) +assert_rpm_wakelock_held(struct drm_i915_private *i915) { - assert_rpm_device_not_suspended(dev_priv); - WARN_ONCE(!atomic_read(&dev_priv->runtime_pm.wakeref_count), + assert_rpm_device_not_suspended(i915); + WARN_ONCE(!atomic_read(&i915->runtime_pm.wakeref_count), "RPM wakelock ref not held during HW access"); } /** * disable_rpm_wakeref_asserts - disable the RPM assert checks - * @dev_priv: i915 device instance + * @i915: i915 device instance * * This function disable asserts that check if we hold an RPM wakelock * reference, while keeping the device-not-suspended checks still enabled. @@ -2028,14 +2032,14 @@ assert_rpm_wakelock_held(struct drm_i915_private *dev_priv) * enable_rpm_wakeref_asserts(). */ static inline void -disable_rpm_wakeref_asserts(struct drm_i915_private *dev_priv) +disable_rpm_wakeref_asserts(struct drm_i915_private *i915) { - atomic_inc(&dev_priv->runtime_pm.wakeref_count); + atomic_inc(&i915->runtime_pm.wakeref_count); } /** * enable_rpm_wakeref_asserts - re-enable the RPM assert checks - * @dev_priv: i915 device instance + * @i915: i915 device instance * * This function re-enables the RPM assert checks after disabling them with * disable_rpm_wakeref_asserts. It's meant to be used only in special @@ -2045,15 +2049,25 @@ disable_rpm_wakeref_asserts(struct drm_i915_private *dev_priv) * disable_rpm_wakeref_asserts(). */ static inline void -enable_rpm_wakeref_asserts(struct drm_i915_private *dev_priv) +enable_rpm_wakeref_asserts(struct drm_i915_private *i915) { - atomic_dec(&dev_priv->runtime_pm.wakeref_count); + atomic_dec(&i915->runtime_pm.wakeref_count); } -void intel_runtime_pm_get(struct drm_i915_private *dev_priv); -bool intel_runtime_pm_get_if_in_use(struct drm_i915_private *dev_priv); -void intel_runtime_pm_get_noresume(struct drm_i915_private *dev_priv); -void intel_runtime_pm_put(struct drm_i915_private *dev_priv); +void intel_runtime_pm_get(struct drm_i915_private *i915); +bool intel_runtime_pm_get_if_in_use(struct drm_i915_private *i915); +void intel_runtime_pm_get_noresume(struct drm_i915_private *i915); +void intel_runtime_pm_put(struct drm_i915_private *i915); + +#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM) +void print_intel_runtime_pm_wakeref(struct drm_i915_private *i915, + struct drm_printer *p); +#else +static inline void print_intel_runtime_pm_wakeref(struct drm_i915_private *i915, + struct drm_printer *p) +{ +} +#endif void chv_phy_powergate_lanes(struct intel_encoder *encoder, bool override, unsigned int mask); diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c index 480dadb1047b..7d9455619db6 100644 --- a/drivers/gpu/drm/i915/intel_runtime_pm.c +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c @@ -29,6 +29,8 @@ #include <linux/pm_runtime.h> #include <linux/vgaarb.h> +#include <drm/drm_print.h> + #include "i915_drv.h" #include "intel_drv.h" @@ -49,6 +51,189 @@ * present for a given platform. */ +#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM) + +#include <linux/sort.h> + +#define STACKDEPTH 8 + +static void init_intel_runtime_pm_wakeref(struct drm_i915_private *i915) +{ + spin_lock_init(&i915->runtime_pm.debug_lock); +} + +static noinline void +track_intel_runtime_pm_wakeref(struct drm_i915_private *i915) +{ + struct i915_runtime_pm *rpm = &i915->runtime_pm; + unsigned long entries[STACKDEPTH]; + struct stack_trace trace = { + .entries = entries, + .max_entries = ARRAY_SIZE(entries), + .skip = 1 + }; + unsigned long flags; + depot_stack_handle_t stack, *stacks; + + if (!HAS_RUNTIME_PM(i915)) + return; + + save_stack_trace(&trace); + if (trace.nr_entries && + trace.entries[trace.nr_entries - 1] == ULONG_MAX) + trace.nr_entries--; + + stack = depot_save_stack(&trace, GFP_NOWAIT | __GFP_NOWARN); + if (!stack) + return; + + spin_lock_irqsave(&rpm->debug_lock, flags); + stacks = krealloc(rpm->debug_owners, + (rpm->debug_count + 1) * sizeof(*stacks), + GFP_NOWAIT | __GFP_NOWARN); + if (stacks) { + stacks[rpm->debug_count++] = stack; + rpm->debug_owners = stacks; + } + spin_unlock_irqrestore(&rpm->debug_lock, flags); +} + +static void untrack_intel_runtime_pm_wakeref(struct drm_i915_private *i915) +{ + struct i915_runtime_pm *rpm = &i915->runtime_pm; + depot_stack_handle_t *stacks; + unsigned long flags; + + spin_lock_irqsave(&rpm->debug_lock, flags); + stacks = fetch_and_zero(&rpm->debug_owners); + rpm->debug_count = 0; + spin_unlock_irqrestore(&rpm->debug_lock, flags); + + kfree(stacks); +} + +static int cmphandle(const void *_a, const void *_b) +{ + const depot_stack_handle_t * const a = _a, * const b = _b; + + if (*a < *b) + return -1; + else if (*a > *b) + return 1; + else + return 0; +} + +static void __print_intel_runtime_pm_wakeref(struct drm_printer *p, + depot_stack_handle_t *stacks, + unsigned long count) +{ + unsigned long entries[STACKDEPTH]; + unsigned long i; + char *buf; + + drm_printf(p, "Wakeref count: %lu\n", count); + + buf = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!buf) + return; + + sort(stacks, count, sizeof(*stacks), cmphandle, NULL); + + for (i = 0; i < count; i++) { + struct stack_trace trace = { + .entries = entries, + .max_entries = ARRAY_SIZE(entries), + }; + depot_stack_handle_t stack = stacks[i]; + unsigned long rep; + + rep = 1; + while (i + 1 < count && stacks[i + 1] == stack) + rep++, i++; + depot_fetch_stack(stack, &trace); + snprint_stack_trace(buf, PAGE_SIZE, &trace, 2); + drm_printf(p, "Wakeref x%lu taken at:\n%s", rep, buf); + } + + kfree(buf); +} + +static void show_intel_runtime_pm_wakeref(struct drm_i915_private *i915) +{ + struct i915_runtime_pm *rpm = &i915->runtime_pm; + depot_stack_handle_t *stacks; + unsigned long flags, count; + struct drm_printer p; + + spin_lock_irqsave(&rpm->debug_lock, flags); + stacks = fetch_and_zero(&rpm->debug_owners); + count = fetch_and_zero(&rpm->debug_count); + spin_unlock_irqrestore(&rpm->debug_lock, flags); + if (!count) + return; + + p = drm_debug_printer("i915"); + __print_intel_runtime_pm_wakeref(&p, stacks, count); + + kfree(stacks); +} + +void print_intel_runtime_pm_wakeref(struct drm_i915_private *i915, + struct drm_printer *p) +{ + depot_stack_handle_t *stacks = NULL; + unsigned long count = 0; + + do { + struct i915_runtime_pm *rpm = &i915->runtime_pm; + unsigned long alloc = count; + depot_stack_handle_t *s; + + spin_lock_irq(&rpm->debug_lock); + count = rpm->debug_count; + if (count == alloc) { + memcpy(stacks, + rpm->debug_owners, + count * sizeof(*stacks)); + } + spin_unlock_irq(&rpm->debug_lock); + if (count == alloc) + break; + + s = krealloc(stacks, count * sizeof(*stacks), GFP_KERNEL); + if (!s) + goto out; + + stacks = s; + } while (1); + + __print_intel_runtime_pm_wakeref(p, stacks, count); + +out: + kfree(stacks); +} + +#else + +static void init_intel_runtime_pm_wakeref(struct drm_i915_private *i915) +{ +} + +static void track_intel_runtime_pm_wakeref(struct drm_i915_private *i915) +{ +} + +static void untrack_intel_runtime_pm_wakeref(struct drm_i915_private *i915) +{ +} + +static void show_intel_runtime_pm_wakeref(struct drm_i915_private *i915) +{ +} + +#endif + bool intel_display_power_well_is_enabled(struct drm_i915_private *dev_priv, enum i915_power_well_id power_well_id); @@ -4000,7 +4185,7 @@ static void intel_power_domains_verify_state(struct drm_i915_private *dev_priv) /** * intel_runtime_pm_get - grab a runtime pm reference - * @dev_priv: i915 device instance + * @i915: i915 device instance * * This function grabs a device-level runtime pm reference (mostly used for GEM * code to ensure the GTT or GT is on) and ensures that it is powered up. @@ -4008,22 +4193,24 @@ static void intel_power_domains_verify_state(struct drm_i915_private *dev_priv) * Any runtime pm reference obtained by this function must have a symmetric * call to intel_runtime_pm_put() to release the reference again. */ -void intel_runtime_pm_get(struct drm_i915_private *dev_priv) +void intel_runtime_pm_get(struct drm_i915_private *i915) { - struct pci_dev *pdev = dev_priv->drm.pdev; + struct pci_dev *pdev = i915->drm.pdev; struct device *kdev = &pdev->dev; int ret; ret = pm_runtime_get_sync(kdev); WARN_ONCE(ret < 0, "pm_runtime_get_sync() failed: %d\n", ret); - atomic_inc(&dev_priv->runtime_pm.wakeref_count); - assert_rpm_wakelock_held(dev_priv); + atomic_inc(&i915->runtime_pm.wakeref_count); + assert_rpm_wakelock_held(i915); + + track_intel_runtime_pm_wakeref(i915); } /** * intel_runtime_pm_get_if_in_use - grab a runtime pm reference if device in use - * @dev_priv: i915 device instance + * @i915: i915 device instance * * This function grabs a device-level runtime pm reference if the device is * already in use and ensures that it is powered up. It is illegal to try @@ -4034,10 +4221,10 @@ void intel_runtime_pm_get(struct drm_i915_private *dev_priv) * * Returns: True if the wakeref was acquired, or False otherwise. */ -bool intel_runtime_pm_get_if_in_use(struct drm_i915_private *dev_priv) +bool intel_runtime_pm_get_if_in_use(struct drm_i915_private *i915) { if (IS_ENABLED(CONFIG_PM)) { - struct pci_dev *pdev = dev_priv->drm.pdev; + struct pci_dev *pdev = i915->drm.pdev; struct device *kdev = &pdev->dev; /* @@ -4050,15 +4237,17 @@ bool intel_runtime_pm_get_if_in_use(struct drm_i915_private *dev_priv) return false; } - atomic_inc(&dev_priv->runtime_pm.wakeref_count); - assert_rpm_wakelock_held(dev_priv); + atomic_inc(&i915->runtime_pm.wakeref_count); + assert_rpm_wakelock_held(i915); + + track_intel_runtime_pm_wakeref(i915); return true; } /** * intel_runtime_pm_get_noresume - grab a runtime pm reference - * @dev_priv: i915 device instance + * @i915: i915 device instance * * This function grabs a device-level runtime pm reference (mostly used for GEM * code to ensure the GTT or GT is on). @@ -4073,32 +4262,35 @@ bool intel_runtime_pm_get_if_in_use(struct drm_i915_private *dev_priv) * Any runtime pm reference obtained by this function must have a symmetric * call to intel_runtime_pm_put() to release the reference again. */ -void intel_runtime_pm_get_noresume(struct drm_i915_private *dev_priv) +void intel_runtime_pm_get_noresume(struct drm_i915_private *i915) { - struct pci_dev *pdev = dev_priv->drm.pdev; + struct pci_dev *pdev = i915->drm.pdev; struct device *kdev = &pdev->dev; - assert_rpm_wakelock_held(dev_priv); + assert_rpm_wakelock_held(i915); pm_runtime_get_noresume(kdev); - atomic_inc(&dev_priv->runtime_pm.wakeref_count); + atomic_inc(&i915->runtime_pm.wakeref_count); + + track_intel_runtime_pm_wakeref(i915); } /** * intel_runtime_pm_put - release a runtime pm reference - * @dev_priv: i915 device instance + * @i915: i915 device instance * * This function drops the device-level runtime pm reference obtained by * intel_runtime_pm_get() and might power down the corresponding * hardware block right away if this is the last reference. */ -void intel_runtime_pm_put(struct drm_i915_private *dev_priv) +void intel_runtime_pm_put(struct drm_i915_private *i915) { - struct pci_dev *pdev = dev_priv->drm.pdev; + struct pci_dev *pdev = i915->drm.pdev; struct device *kdev = &pdev->dev; - assert_rpm_wakelock_held(dev_priv); - atomic_dec(&dev_priv->runtime_pm.wakeref_count); + assert_rpm_wakelock_held(i915); + if (atomic_dec_and_test(&i915->runtime_pm.wakeref_count)) + untrack_intel_runtime_pm_wakeref(i915); pm_runtime_mark_last_busy(kdev); pm_runtime_put_autosuspend(kdev); @@ -4106,7 +4298,7 @@ void intel_runtime_pm_put(struct drm_i915_private *dev_priv) /** * intel_runtime_pm_enable - enable runtime pm - * @dev_priv: i915 device instance + * @i915: i915 device instance * * This function enables runtime pm at the end of the driver load sequence. * @@ -4114,9 +4306,9 @@ void intel_runtime_pm_put(struct drm_i915_private *dev_priv) * subordinate display power domains. That is done by * intel_power_domains_enable(). */ -void intel_runtime_pm_enable(struct drm_i915_private *dev_priv) +void intel_runtime_pm_enable(struct drm_i915_private *i915) { - struct pci_dev *pdev = dev_priv->drm.pdev; + struct pci_dev *pdev = i915->drm.pdev; struct device *kdev = &pdev->dev; /* @@ -4138,7 +4330,7 @@ void intel_runtime_pm_enable(struct drm_i915_private *dev_priv) * so the driver's own RPM reference tracking asserts also work on * platforms without RPM support. */ - if (!HAS_RUNTIME_PM(dev_priv)) { + if (!HAS_RUNTIME_PM(i915)) { int ret; pm_runtime_dont_use_autosuspend(kdev); @@ -4156,17 +4348,36 @@ void intel_runtime_pm_enable(struct drm_i915_private *dev_priv) pm_runtime_put_autosuspend(kdev); } -void intel_runtime_pm_disable(struct drm_i915_private *dev_priv) +void intel_runtime_pm_disable(struct drm_i915_private *i915) { - struct pci_dev *pdev = dev_priv->drm.pdev; + struct pci_dev *pdev = i915->drm.pdev; struct device *kdev = &pdev->dev; /* Transfer rpm ownership back to core */ - WARN(pm_runtime_get_sync(&dev_priv->drm.pdev->dev) < 0, + WARN(pm_runtime_get_sync(kdev) < 0, "Failed to pass rpm ownership back to core\n"); pm_runtime_dont_use_autosuspend(kdev); - if (!HAS_RUNTIME_PM(dev_priv)) + if (!HAS_RUNTIME_PM(i915)) pm_runtime_put(kdev); } + +void intel_runtime_pm_cleanup(struct drm_i915_private *i915) +{ + struct i915_runtime_pm *rpm = &i915->runtime_pm; + + if (WARN(atomic_read(&rpm->wakeref_count), + "i915->runtime_pm.wakeref_count=%d on cleanup\n", + atomic_read(&rpm->wakeref_count))) { + show_intel_runtime_pm_wakeref(i915); + atomic_set(&rpm->wakeref_count, 0); + } + + untrack_intel_runtime_pm_wakeref(i915); +} + +void intel_runtime_pm_init_early(struct drm_i915_private *i915) +{ + init_intel_runtime_pm_wakeref(i915); +} diff --git a/drivers/gpu/drm/i915/selftests/mock_gem_device.c b/drivers/gpu/drm/i915/selftests/mock_gem_device.c index 43ed8b28aeaa..0eb283e7fc96 100644 --- a/drivers/gpu/drm/i915/selftests/mock_gem_device.c +++ b/drivers/gpu/drm/i915/selftests/mock_gem_device.c @@ -154,15 +154,17 @@ struct drm_i915_private *mock_gem_device(void) pdev->dev.archdata.iommu = (void *)-1; #endif + i915 = (struct drm_i915_private *)(pdev + 1); + pci_set_drvdata(pdev, i915); + + intel_runtime_pm_init_early(i915); + dev_pm_domain_set(&pdev->dev, &pm_domain); pm_runtime_enable(&pdev->dev); pm_runtime_dont_use_autosuspend(&pdev->dev); if (pm_runtime_enabled(&pdev->dev)) WARN_ON(pm_runtime_get_sync(&pdev->dev)); - i915 = (struct drm_i915_private *)(pdev + 1); - pci_set_drvdata(pdev, i915); - err = drm_dev_init(&i915->drm, &mock_driver, &pdev->dev); if (err) { pr_err("Failed to initialise mock GEM device: err=%d\n", err); -- 2.19.0.rc2 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx