From: Chris Wilson <chris.p.wil...@intel.com>
Extract the callstack tracking of intel_runtime_pm.c into its own
utility so that that we can reuse it for other online debugging of
scoped wakerefs.
Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk>
Signed-off-by: Andrzej Hajda <andrzej.ha...@intel.com>
---
drivers/gpu/drm/i915/Kconfig.debug | 9 +
drivers/gpu/drm/i915/Makefile | 4 +
drivers/gpu/drm/i915/intel_runtime_pm.c | 244 +++------------------------
drivers/gpu/drm/i915/intel_runtime_pm.h | 10 +-
drivers/gpu/drm/i915/intel_wakeref.h | 6 +-
drivers/gpu/drm/i915/intel_wakeref_tracker.c | 234 +++++++++++++++++++++++++
drivers/gpu/drm/i915/intel_wakeref_tracker.h | 76 +++++++++
7 files changed, 355 insertions(+), 228 deletions(-)
diff --git a/drivers/gpu/drm/i915/Kconfig.debug
b/drivers/gpu/drm/i915/Kconfig.debug
index 93dfb7ed970547..5fde52107e3b44 100644
--- a/drivers/gpu/drm/i915/Kconfig.debug
+++ b/drivers/gpu/drm/i915/Kconfig.debug
@@ -25,6 +25,7 @@ config DRM_I915_DEBUG
select PREEMPT_COUNT
select I2C_CHARDEV
select STACKDEPOT
+ select STACKTRACE
select DRM_DP_AUX_CHARDEV
select X86_MSR # used by igt/pm_rpm
select DRM_VGEM # used by igt/prime_vgem (dmabuf interop checks)
@@ -37,6 +38,7 @@ config DRM_I915_DEBUG
select DRM_I915_DEBUG_GEM
select DRM_I915_DEBUG_GEM_ONCE
select DRM_I915_DEBUG_MMIO
+ select DRM_I915_TRACK_WAKEREF
select DRM_I915_DEBUG_RUNTIME_PM
select DRM_I915_SW_FENCE_DEBUG_OBJECTS
select DRM_I915_SELFTEST
@@ -227,11 +229,18 @@ config DRM_I915_DEBUG_VBLANK_EVADE
If in doubt, say "N".
+config DRM_I915_TRACK_WAKEREF
+ depends on STACKDEPOT
+ depends on STACKTRACE
+ bool
+
config DRM_I915_DEBUG_RUNTIME_PM
bool "Enable extra state checking for runtime PM"
depends on DRM_I915
default n
select STACKDEPOT
+ select STACKTRACE
+ select DRM_I915_TRACK_WAKEREF
help
Choose this option to turn on extra state checking for the
runtime PM functionality. This may introduce overhead during
diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index b2f91a1f826858..42daff6d575a82 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -81,6 +81,10 @@ i915-$(CONFIG_DEBUG_FS) += \
i915_debugfs_params.o \
display/intel_display_debugfs.o \
display/intel_pipe_crc.o
+
+i915-$(CONFIG_DRM_I915_TRACK_WAKEREF) += \
+ intel_wakeref_tracker.o
+
i915-$(CONFIG_PERF_EVENTS) += i915_pmu.o
# "Graphics Technology" (aka we talk to the gpu)
diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c
b/drivers/gpu/drm/i915/intel_runtime_pm.c
index 129746713d072f..72887e2bb03c21 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -52,182 +52,37 @@
#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM)
-#include <linux/sort.h>
-
-#define STACKDEPTH 8
-
-static noinline depot_stack_handle_t __save_depot_stack(void)
-{
- unsigned long entries[STACKDEPTH];
- unsigned int n;
-
- n = stack_trace_save(entries, ARRAY_SIZE(entries), 1);
- return stack_depot_save(entries, n, GFP_NOWAIT | __GFP_NOWARN);
-}
-
static void init_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm)
{
- spin_lock_init(&rpm->debug.lock);
- stack_depot_init();
+ intel_wakeref_tracker_init(&rpm->debug);
}
-static noinline depot_stack_handle_t
+static intel_wakeref_t
track_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm)
{
- depot_stack_handle_t stack, *stacks;
- unsigned long flags;
-
- if (rpm->no_wakeref_tracking)
- return -1;
-
- stack = __save_depot_stack();
- if (!stack)
+ if (!rpm->available)
return -1;
- spin_lock_irqsave(&rpm->debug.lock, flags);
-
- if (!rpm->debug.count)
- rpm->debug.last_acquire = stack;
-
- 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;
- } else {
- stack = -1;
- }
-
- spin_unlock_irqrestore(&rpm->debug.lock, flags);
-
- return stack;
+ return intel_wakeref_tracker_add(&rpm->debug);
}
static void untrack_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm,
- depot_stack_handle_t stack)
+ intel_wakeref_t wakeref)
{
- struct drm_i915_private *i915 = container_of(rpm,
- struct drm_i915_private,
- runtime_pm);
- unsigned long flags, n;
- bool found = false;
-
- if (unlikely(stack == -1))
- return;
-
- spin_lock_irqsave(&rpm->debug.lock, flags);
- for (n = rpm->debug.count; n--; ) {
- if (rpm->debug.owners[n] == stack) {
- memmove(rpm->debug.owners + n,
- rpm->debug.owners + n + 1,
- (--rpm->debug.count - n) * sizeof(stack));
- found = true;
- break;
- }
- }
- spin_unlock_irqrestore(&rpm->debug.lock, flags);
-
- if (drm_WARN(&i915->drm, !found,
- "Unmatched wakeref (tracking %lu), count %u\n",
- rpm->debug.count, atomic_read(&rpm->wakeref_count))) {
- char *buf;
-
- buf = kmalloc(PAGE_SIZE, GFP_NOWAIT | __GFP_NOWARN);
- if (!buf)
- return;
-
- stack_depot_snprint(stack, buf, PAGE_SIZE, 2);
- DRM_DEBUG_DRIVER("wakeref %x from\n%s", stack, buf);
-
- stack = READ_ONCE(rpm->debug.last_release);
- if (stack) {
- stack_depot_snprint(stack, buf, PAGE_SIZE, 2);
- DRM_DEBUG_DRIVER("wakeref last released at\n%s", buf);
- }
-
- kfree(buf);
- }
+ intel_wakeref_tracker_remove(&rpm->debug, wakeref);
}
-static int cmphandle(const void *_a, const void *_b)
+static void untrack_all_intel_runtime_pm_wakerefs(struct intel_runtime_pm *rpm)
{
- const depot_stack_handle_t * const a = _a, * const b = _b;
+ struct drm_printer p = drm_debug_printer("i915");
- 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,
- const struct intel_runtime_pm_debug *dbg)
-{
- unsigned long i;
- char *buf;
-
- buf = kmalloc(PAGE_SIZE, GFP_NOWAIT | __GFP_NOWARN);
- if (!buf)
- return;
-
- if (dbg->last_acquire) {
- stack_depot_snprint(dbg->last_acquire, buf, PAGE_SIZE, 2);
- drm_printf(p, "Wakeref last acquired:\n%s", buf);
- }
-
- if (dbg->last_release) {
- stack_depot_snprint(dbg->last_release, buf, PAGE_SIZE, 2);
- drm_printf(p, "Wakeref last released:\n%s", buf);
- }
-
- drm_printf(p, "Wakeref count: %lu\n", dbg->count);
-
- sort(dbg->owners, dbg->count, sizeof(*dbg->owners), cmphandle, NULL);
-
- for (i = 0; i < dbg->count; i++) {
- depot_stack_handle_t stack = dbg->owners[i];
- unsigned long rep;
-
- rep = 1;
- while (i + 1 < dbg->count && dbg->owners[i + 1] == stack)
- rep++, i++;
- stack_depot_snprint(stack, buf, PAGE_SIZE, 2);
- drm_printf(p, "Wakeref x%lu taken at:\n%s", rep, buf);
- }
-
- kfree(buf);
-}
-
-static noinline void
-__untrack_all_wakerefs(struct intel_runtime_pm_debug *debug,
- struct intel_runtime_pm_debug *saved)
-{
- *saved = *debug;
-
- debug->owners = NULL;
- debug->count = 0;
- debug->last_release = __save_depot_stack();
-}
-
-static void
-dump_and_free_wakeref_tracking(struct intel_runtime_pm_debug *debug)
-{
- if (debug->count) {
- struct drm_printer p = drm_debug_printer("i915");
-
- __print_intel_runtime_pm_wakeref(&p, debug);
- }
-
- kfree(debug->owners);
+ intel_wakeref_tracker_reset(&rpm->debug, &p);
}
static noinline void
__intel_wakeref_dec_and_check_tracking(struct intel_runtime_pm *rpm)
{
- struct intel_runtime_pm_debug dbg = {};
+ struct intel_wakeref_tracker saved;
unsigned long flags;
if (!atomic_dec_and_lock_irqsave(&rpm->wakeref_count,
@@ -235,60 +90,21 @@ __intel_wakeref_dec_and_check_tracking(struct
intel_runtime_pm *rpm)
flags))
return;
- __untrack_all_wakerefs(&rpm->debug, &dbg);
+ saved = __intel_wakeref_tracker_reset(&rpm->debug);
spin_unlock_irqrestore(&rpm->debug.lock, flags);
- dump_and_free_wakeref_tracking(&dbg);
-}
-
-static noinline void
-untrack_all_intel_runtime_pm_wakerefs(struct intel_runtime_pm *rpm)
-{
- struct intel_runtime_pm_debug dbg = {};
- unsigned long flags;
-
- spin_lock_irqsave(&rpm->debug.lock, flags);
- __untrack_all_wakerefs(&rpm->debug, &dbg);
- spin_unlock_irqrestore(&rpm->debug.lock, flags);
+ if (saved.count) {
+ struct drm_printer p = drm_debug_printer("i915");
- dump_and_free_wakeref_tracking(&dbg);
+ __intel_wakeref_tracker_show(&saved, &p);
+ intel_wakeref_tracker_fini(&saved);
+ }
}
void print_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm,
struct drm_printer *p)
{
- struct intel_runtime_pm_debug dbg = {};
-
- do {
- unsigned long alloc = dbg.count;
- depot_stack_handle_t *s;
-
- spin_lock_irq(&rpm->debug.lock);
- dbg.count = rpm->debug.count;
- if (dbg.count <= alloc) {
- memcpy(dbg.owners,
- rpm->debug.owners,
- dbg.count * sizeof(*s));
- }
- dbg.last_acquire = rpm->debug.last_acquire;
- dbg.last_release = rpm->debug.last_release;
- spin_unlock_irq(&rpm->debug.lock);
- if (dbg.count <= alloc)
- break;
-
- s = krealloc(dbg.owners,
- dbg.count * sizeof(*s),
- GFP_NOWAIT | __GFP_NOWARN);
- if (!s)
- goto out;
-
- dbg.owners = s;
- } while (1);
-
- __print_intel_runtime_pm_wakeref(p, &dbg);
-
-out:
- kfree(dbg.owners);
+ intel_wakeref_tracker_show(&rpm->debug, p);
}
#else
@@ -297,14 +113,14 @@ static void init_intel_runtime_pm_wakeref(struct
intel_runtime_pm *rpm)
{
}
-static depot_stack_handle_t
+static intel_wakeref_t
track_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm)
{
return -1;
}
static void untrack_intel_runtime_pm_wakeref(struct intel_runtime_pm *rpm,
- intel_wakeref_t wref)
+ intel_wakeref_t wakeref)
{
}
@@ -349,9 +165,8 @@ intel_runtime_pm_release(struct intel_runtime_pm *rpm, int wakelock)
static intel_wakeref_t __intel_runtime_pm_get(struct intel_runtime_pm *rpm,
bool wakelock)
{
- struct drm_i915_private *i915 = container_of(rpm,
- struct drm_i915_private,
- runtime_pm);
+ struct drm_i915_private *i915 =
+ container_of(rpm, struct drm_i915_private, runtime_pm);
int ret;
ret = pm_runtime_get_sync(rpm->kdev);
@@ -556,9 +371,8 @@ void intel_runtime_pm_put(struct intel_runtime_pm *rpm,
intel_wakeref_t wref)
*/
void intel_runtime_pm_enable(struct intel_runtime_pm *rpm)
{
- struct drm_i915_private *i915 = container_of(rpm,
- struct drm_i915_private,
- runtime_pm);
+ struct drm_i915_private *i915 =
+ container_of(rpm, struct drm_i915_private, runtime_pm);
struct device *kdev = rpm->kdev;
/*
@@ -611,9 +425,8 @@ void intel_runtime_pm_enable(struct intel_runtime_pm *rpm)
void intel_runtime_pm_disable(struct intel_runtime_pm *rpm)
{
- struct drm_i915_private *i915 = container_of(rpm,
- struct drm_i915_private,
- runtime_pm);
+ struct drm_i915_private *i915 =
+ container_of(rpm, struct drm_i915_private, runtime_pm);
struct device *kdev = rpm->kdev;
/* Transfer rpm ownership back to core */
@@ -628,9 +441,8 @@ void intel_runtime_pm_disable(struct intel_runtime_pm *rpm)
void intel_runtime_pm_driver_release(struct intel_runtime_pm *rpm)
{
- struct drm_i915_private *i915 = container_of(rpm,
- struct drm_i915_private,
- runtime_pm);
+ struct drm_i915_private *i915 =
+ container_of(rpm, struct drm_i915_private, runtime_pm);
int count = atomic_read(&rpm->wakeref_count);
intel_wakeref_auto_fini(&rpm->userfault_wakeref);
@@ -646,7 +458,7 @@ void intel_runtime_pm_driver_release(struct
intel_runtime_pm *rpm)
void intel_runtime_pm_init_early(struct intel_runtime_pm *rpm)
{
struct drm_i915_private *i915 =
- container_of(rpm, struct drm_i915_private, runtime_pm);
+ container_of(rpm, struct drm_i915_private, runtime_pm);
