- reduce the irq disabled section, even for a debugfs file this was
way too long.
- always disable irqs when taking the lock.
v2: Thou shalt not mistake locking for reference counting, so:
- reference count the error_state to protect from concurent freeeing.
This will be only really used in the next patch.
Signed-Off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
drivers/gpu/drm/i915/i915_debugfs.c | 13 ++++++++-----
drivers/gpu/drm/i915/i915_drv.h | 4 ++++
drivers/gpu/drm/i915/i915_irq.c | 12 +++++++-----
3 files changed, 19 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 3f6e28e..b46c198 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -701,12 +701,16 @@ static int i915_error_state(struct seq_file *m, void *unused)
int i, j, page, offset, elt;
spin_lock_irqsave(&dev_priv->error_lock, flags);
- if (!dev_priv->first_error) {
+ error = dev_priv->first_error;
+ if (error)
+ kref_get(&error->ref);
+ spin_unlock_irqrestore(&dev_priv->error_lock, flags);
+
+ if (!error) {
seq_printf(m, "no error state collected\n");
- goto out;
+ return 0;
}
- error = dev_priv->first_error;
seq_printf(m, "Time: %ld s %ld us\n", error->time.tv_sec,
error->time.tv_usec);
@@ -788,8 +792,7 @@ static int i915_error_state(struct seq_file *m, void *unused)
if (error->display)
intel_display_print_error_state(m, dev, error->display);
-out:
- spin_unlock_irqrestore(&dev_priv->error_lock, flags);
+ kref_put(&error->ref, i915_error_state_free);
return 0;
}
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 5e62b35..2aaa594 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -39,6 +39,7 @@
#include <drm/intel-gtt.h>
#include <linux/backlight.h>
#include <linux/intel-iommu.h>
+#include <linux/kref.h>
/* General customization:
*/
@@ -171,6 +172,7 @@ struct sdvo_device_mapping {
struct intel_display_error_state;
struct drm_i915_error_state {
+ struct kref ref;
u32 eir;
u32 pgtbl_er;
u32 pipestat[I915_MAX_PIPES];
@@ -466,6 +468,7 @@ typedef struct drm_i915_private {
unsigned int fsb_freq, mem_freq, is_ddr3;
spinlock_t error_lock;
+ /* Protected by dev->error_lock. */
struct drm_i915_error_state *first_error;
struct work_struct error_work;
struct completion error_completion;
@@ -1163,6 +1166,7 @@ extern int i915_vblank_pipe_get(struct drm_device *dev, void *data,
struct drm_file *file_priv);
extern int i915_vblank_swap(struct drm_device *dev, void *data,
struct drm_file *file_priv);
+void i915_error_state_free(struct kref *error_ref);
void
i915_enable_pipestat(drm_i915_private_t *dev_priv, int pipe, u32 mask);
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 5c360ee..b6c02eb 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -869,10 +869,11 @@ i915_error_object_free(struct drm_i915_error_object *obj)
kfree(obj);
}
-static void
-i915_error_state_free(struct drm_device *dev,
- struct drm_i915_error_state *error)
+void
+i915_error_state_free(struct kref *error_ref)
{
+ struct drm_i915_error_state *error = container_of(error_ref,
+ typeof(*error), ref);
int i;
for (i = 0; i < ARRAY_SIZE(error->ring); i++) {
@@ -1120,6 +1121,7 @@ static void i915_capture_error_state(struct drm_device *dev)
DRM_INFO("capturing error event; look for more information in /debug/dri/%d/i915_error_state\n",
dev->primary->index);
+ kref_init(&error->ref);
error->eir = I915_READ(EIR);
error->pgtbl_er = I915_READ(PGTBL_ER);
for_each_pipe(pipe)
@@ -1181,7 +1183,7 @@ static void i915_capture_error_state(struct drm_device *dev)
spin_unlock_irqrestore(&dev_priv->error_lock, flags);
if (error)
- i915_error_state_free(dev, error);
+ i915_error_state_free(&error->ref);
}
void i915_destroy_error_state(struct drm_device *dev)
@@ -1196,7 +1198,7 @@ void i915_destroy_error_state(struct drm_device *dev)
spin_unlock_irqrestore(&dev_priv->error_lock, flags);
if (error)
- i915_error_state_free(dev, error);
+ kref_put(&error->ref, i915_error_state_free);
}
#else
#define i915_capture_error_state(x)
--
1.7.9
