Still missing: Updated kerneldoc and integration into the docbook. Also, this isn't a full review yet.
Should be squashed into Rob's patch.
Signed-off-by: Daniel Vetter daniel.vetter@ffwll.ch --- drivers/gpu/drm/drm_crtc.c | 4 +- drivers/gpu/drm/drm_modeset_lock.c | 72 ++++++++++++------------------------ drivers/gpu/drm/i915/intel_display.c | 3 +- include/drm/drm_modeset_lock.h | 41 +------------------- include/uapi/drm/drm_mode.h | 3 -- 5 files changed, 28 insertions(+), 95 deletions(-)
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index cf622f6de07c..9e826aa5fc5c 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -39,6 +39,7 @@ #include <drm/drm_fourcc.h> #include <drm/drm_modeset_lock.h>
+#include "drm_crtc_internal.h"
/** * drm_modeset_lock_all - take all modeset locks @@ -60,7 +61,7 @@ void drm_modeset_lock_all(struct drm_device *dev)
mutex_lock(&config->mutex);
- drm_modeset_acquire_init(ctx, false, false); + drm_modeset_acquire_init(ctx);
retry: ret = drm_modeset_lock(&config->connection_mutex, ctx); @@ -105,7 +106,6 @@ void drm_modeset_unlock_all(struct drm_device *dev)
config->acquire_ctx = NULL; drm_modeset_drop_locks(ctx); - ww_acquire_fini(&ctx->ww_ctx); drm_modeset_acquire_fini(ctx);
kfree(ctx); diff --git a/drivers/gpu/drm/drm_modeset_lock.c b/drivers/gpu/drm/drm_modeset_lock.c index 6580d6ce8f63..81607ccebd89 100644 --- a/drivers/gpu/drm/drm_modeset_lock.c +++ b/drivers/gpu/drm/drm_modeset_lock.c @@ -26,32 +26,21 @@ #include <drm/drm_modeset_lock.h>
-void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx, - bool nolock, bool nonblock) +void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx) { ww_acquire_init(&ctx->ww_ctx, &crtc_ww_class); INIT_LIST_HEAD(&ctx->locked); - mutex_init(&ctx->mutex); - ctx->nolock = nolock; - ctx->nonblock = nonblock; } EXPORT_SYMBOL(drm_modeset_acquire_init);
void drm_modeset_acquire_fini(struct drm_modeset_acquire_ctx *ctx) { - WARN_ON(ctx->contended); - /* - * NOTE: it is intentional that ww_acquire_fini() is not called - * here.. due to the way lock handover works in drm_atomic - */ - mutex_destroy(&ctx->mutex); + ww_acquire_fini(&ctx->ww_ctx); } EXPORT_SYMBOL(drm_modeset_acquire_fini);
void drm_modeset_drop_locks(struct drm_modeset_acquire_ctx *ctx) { - WARN_ON(ctx->contended); - mutex_lock(&ctx->mutex); while (!list_empty(&ctx->locked)) { struct drm_modeset_lock *lock;
@@ -60,45 +49,31 @@ void drm_modeset_drop_locks(struct drm_modeset_acquire_ctx *ctx)
drm_modeset_unlock(lock); } - mutex_unlock(&ctx->mutex); } EXPORT_SYMBOL(drm_modeset_drop_locks);
static int modeset_lock(struct drm_modeset_lock *lock, - struct drm_modeset_acquire_ctx *ctx, - bool interruptible, bool slow) + struct drm_modeset_acquire_ctx *ctx, + bool interruptible) { int ret;
- if (ctx->nolock) - return 0; - - WARN_ON(ctx->frozen); /* all locks should be held by now! */ - WARN_ON(ctx->contended); - -retry: if (interruptible) { ret = ww_mutex_lock_interruptible(&lock->mutex, &ctx->ww_ctx); - } else if (slow) { - ww_mutex_lock_slow(&lock->mutex, &ctx->ww_ctx); - ret = 0; } else { ret = ww_mutex_lock(&lock->mutex, &ctx->ww_ctx); } - if (!ret) { - if (lock->atomic_pending) { - /* some other pending update with dropped locks */ - ww_mutex_unlock(&lock->mutex); - if (ctx->nonblock) - return -EBUSY; - wait_event(lock->event, !lock->atomic_pending); - goto retry; - } - lock->atomic_pending = true; - WARN_ON(!list_empty(&lock->head)); + + if (ret == 0) { list_add(&lock->head, &ctx->locked); } else if (ret == -EALREADY) { - /* we already hold the lock.. this is fine */ + /* + * We already hold the lock. This is only fine if it's the lock + * we've contended on. + */ + WARN_ON(ctx->contended != lock); + ctx->contended = NULL; + ret = 0; } else if (ret == -EDEADLK) { ctx->contended = lock; @@ -109,18 +84,19 @@ retry:
void drm_modeset_backoff(struct drm_modeset_acquire_ctx *ctx) { - struct drm_modeset_lock *contended = ctx->contended; - - ctx->contended = NULL; + drm_modeset_drop_locks(ctx);
- if (WARN_ON(!contended)) - return; + ww_mutex_lock_slow(&ctx->contended->mutex, ctx); +} +EXPORT_SYMBOL(drm_modeset_backoff);
+void drm_modeset_backoff_interruptible(struct drm_modeset_acquire_ctx *ctx) +{ drm_modeset_drop_locks(ctx);
- modeset_lock(contended, ctx, false, true); + ww_mutex_lock_slow(&ctx->contended->mutex, ctx); } -EXPORT_SYMBOL(drm_modeset_backoff); +EXPORT_SYMBOL(drm_modeset_backoff_interruptible);
/** * drm_modeset_lock - take modeset lock @@ -136,7 +112,7 @@ int drm_modeset_lock(struct drm_modeset_lock *lock, struct drm_modeset_acquire_ctx *ctx) { if (ctx) - return modeset_lock(lock, ctx, false, false); + return modeset_lock(lock, ctx, false);
ww_mutex_lock(&lock->mutex, NULL); return 0; @@ -147,7 +123,7 @@ int drm_modeset_lock_interruptible(struct drm_modeset_lock *lock, struct drm_modeset_acquire_ctx *ctx) { if (ctx) - return modeset_lock(lock, ctx, true, false); + return modeset_lock(lock, ctx, true);
return ww_mutex_lock_interruptible(&lock->mutex, NULL); } @@ -160,9 +136,7 @@ EXPORT_SYMBOL(drm_modeset_lock_interruptible); void drm_modeset_unlock(struct drm_modeset_lock *lock) { list_del_init(&lock->head); - lock->atomic_pending = false; ww_mutex_unlock(&lock->mutex); - wake_up_all(&lock->event); } EXPORT_SYMBOL(drm_modeset_unlock);
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index ba6cbbbfe596..9d12e3e15dfa 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -7990,7 +7990,7 @@ bool intel_get_load_detect_pipe(struct drm_connector *connector, connector->base.id, drm_get_connector_name(connector), encoder->base.id, drm_get_encoder_name(encoder));
- drm_modeset_acquire_init(ctx, false, false); + drm_modeset_acquire_init(ctx);
retry: ret = drm_modeset_lock(&config->connection_mutex, ctx); @@ -8103,7 +8103,6 @@ fail_unlock: }
drm_modeset_drop_locks(ctx); - ww_acquire_fini(&ctx->ww_ctx); drm_modeset_acquire_fini(ctx);
return false; diff --git a/include/drm/drm_modeset_lock.h b/include/drm/drm_modeset_lock.h index 2630da3ef1b4..e67fb815b610 100644 --- a/include/drm/drm_modeset_lock.h +++ b/include/drm/drm_modeset_lock.h @@ -32,15 +32,6 @@ struct drm_modeset_acquire_ctx {
struct ww_acquire_ctx ww_ctx;
- bool nolock : 1; - bool nonblock : 1; - - /* just for debugging, the context is 'frozen' in drm_atomic_check() - * to catch anyone who might be trying to acquire a lock after it is - * too late. - */ - bool frozen : 1; - /* contended lock: if a lock is contended you should only call * drm_modeset_backoff() which drops locks and slow-locks the * contended lock. @@ -49,16 +40,6 @@ struct drm_modeset_acquire_ctx {
/* list of 'struct drm_modeset_lock': */ struct list_head locked; - - /* currently simply for protecting against 'locked' list manipulation - * between original thread calling atomic->end() and driver thread - * calling back drm_atomic_commit_unlocked(). - * - * Other spots are sufficiently synchronized by virtue of holding - * the lock's ww_mutex. But during the lock/resource hand-over to the - * driver thread (drop_locks()/grab_locks()), we cannot rely on this. - */ - struct mutex mutex; };
/** @@ -78,42 +59,24 @@ struct drm_modeset_lock { struct ww_mutex mutex;
/** - * Are we busy (pending asynchronous/NONBLOCK update)? Any further - * asynchronous update will return -EBUSY if it also needs to acquire - * this lock. While a synchronous update will block until the pending - * async update completes. - * - * Drivers must ensure the update is completed before sending vblank - * event to userspace. Typically this just means don't send event - * before drm_atomic_commit_unlocked() returns. - */ - bool atomic_pending; - - /** * Resources that are locked as part of an atomic update are added * to a list (so we know what to unlock at the end). */ struct list_head head; - - /** - * For waiting on atomic_pending locks, if not a NONBLOCK operation. - */ - wait_queue_head_t event; };
extern struct ww_class crtc_ww_class;
-void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx, - bool nolock, bool nonblock); +void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx); void drm_modeset_acquire_fini(struct drm_modeset_acquire_ctx *ctx); void drm_modeset_drop_locks(struct drm_modeset_acquire_ctx *ctx); void drm_modeset_backoff(struct drm_modeset_acquire_ctx *ctx); +void drm_modeset_backoff_interruptible(struct drm_modeset_acquire_ctx *ctx);
static inline void drm_modeset_lock_init(struct drm_modeset_lock *lock) { ww_mutex_init(&lock->mutex, &crtc_ww_class); INIT_LIST_HEAD(&lock->head); - init_waitqueue_head(&lock->event); }
static inline void drm_modeset_lock_fini(struct drm_modeset_lock *lock) diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h index 6421edcd27a8..ded505ede145 100644 --- a/include/uapi/drm/drm_mode.h +++ b/include/uapi/drm/drm_mode.h @@ -511,7 +511,4 @@ struct drm_mode_destroy_dumb { uint32_t handle; };
-#define DRM_MODE_ATOMIC_NONBLOCK 0x0200 -#define DRM_MODE_ATOMIC_NOLOCK 0x8000 /* only used internally */ - #endif