drm/i915: Finally remove obj->mm.lock.

With all callers and selftests fixed to use ww locking, we can now
finally remove this lock.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210323155059.628690-62-maarten.lankhorst@linux.intel.com

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c
index 821cb40f8d73c239b0761522ac36d2e61e9e2dd5..ea74cbca95be0db54867bc7aaac616a688852053 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c
@@ -62,8 +62,6 @@ void i915_gem_object_init(struct drm_i915_gem_object *obj,
                          const struct drm_i915_gem_object_ops *ops,
                          struct lock_class_key *key, unsigned flags)
 {
-       mutex_init(&obj->mm.lock);
-
        spin_lock_init(&obj->vma.lock);
        INIT_LIST_HEAD(&obj->vma.list);
 

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
index 2be6e02e91e1d5e9a748b331259e7dddb6dd0e18..0f9ec3e0707e45a412ec6381da48a9a96daecbed 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
@@ -129,7 +129,7 @@ static inline void assert_object_held_shared(struct drm_i915_gem_object *obj)
         */
        if (IS_ENABLED(CONFIG_LOCKDEP) &&
            kref_read(&obj->base.refcount) > 0)
-               lockdep_assert_held(&obj->mm.lock);
+               assert_object_held(obj);
 }
 
 static inline int __i915_gem_object_lock(struct drm_i915_gem_object *obj,
@@ -358,7 +358,7 @@ int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj);
 static inline int __must_check
 i915_gem_object_pin_pages(struct drm_i915_gem_object *obj)
 {
-       might_lock(&obj->mm.lock);
+       assert_object_held(obj);
 
        if (atomic_inc_not_zero(&obj->mm.pages_pin_count))
                return 0;
@@ -404,7 +404,6 @@ i915_gem_object_unpin_pages(struct drm_i915_gem_object *obj)
 }
 
 int __i915_gem_object_put_pages(struct drm_i915_gem_object *obj);
-int __i915_gem_object_put_pages_locked(struct drm_i915_gem_object *obj);
 void i915_gem_object_truncate(struct drm_i915_gem_object *obj);
 void i915_gem_object_writeback(struct drm_i915_gem_object *obj);
 

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
index dbe12951fa1cd25f97e66dc7dafccdba74519802..8e485cb3343c45ecd93075e39d5a214e3ebfcaf6 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
@@ -216,7 +216,6 @@ struct drm_i915_gem_object {
                 * Protects the pages and their use. Do not use directly, but
                 * instead go through the pin/unpin interfaces.
                 */
-               struct mutex lock;
                atomic_t pages_pin_count;
                atomic_t shrink_pin;
 

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pages.c b/drivers/gpu/drm/i915/gem/i915_gem_pages.c
index 5b8af8f83ee3917002dba616628689d05b3b9f6b..aed8a37ccdc938ea4022b758d59c3a654f2e9bd9 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_pages.c
@@ -70,7 +70,7 @@ void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj,
                struct list_head *list;
                unsigned long flags;
 
-               lockdep_assert_held(&obj->mm.lock);
+               assert_object_held(obj);
                spin_lock_irqsave(&i915->mm.obj_lock, flags);
 
                i915->mm.shrink_count++;
@@ -117,9 +117,7 @@ int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj)
 {
        int err;
 
-       err = mutex_lock_interruptible(&obj->mm.lock);
-       if (err)
-               return err;
+       assert_object_held(obj);
 
        assert_object_held_shared(obj);
 
@@ -128,15 +126,13 @@ int __i915_gem_object_get_pages(struct drm_i915_gem_object *obj)
 
                err = ____i915_gem_object_get_pages(obj);
                if (err)
-                       goto unlock;
+                       return err;
 
                smp_mb__before_atomic();
        }
        atomic_inc(&obj->mm.pages_pin_count);
 
-unlock:
-       mutex_unlock(&obj->mm.lock);
-       return err;
+       return 0;
 }
 
 int i915_gem_object_pin_pages_unlocked(struct drm_i915_gem_object *obj)
@@ -223,7 +219,7 @@ __i915_gem_object_unset_pages(struct drm_i915_gem_object *obj)
        return pages;
 }
 
-int __i915_gem_object_put_pages_locked(struct drm_i915_gem_object *obj)
+int __i915_gem_object_put_pages(struct drm_i915_gem_object *obj)
 {
        struct sg_table *pages;
 
@@ -254,21 +250,6 @@ int __i915_gem_object_put_pages_locked(struct drm_i915_gem_object *obj)
        return 0;
 }
 
-int __i915_gem_object_put_pages(struct drm_i915_gem_object *obj)
-{
-       int err;
-
-       if (i915_gem_object_has_pinned_pages(obj))
-               return -EBUSY;
-
-       /* May be called by shrinker from within get_pages() (on another bo) */
-       mutex_lock(&obj->mm.lock);
-       err = __i915_gem_object_put_pages_locked(obj);
-       mutex_unlock(&obj->mm.lock);
-
-       return err;
-}
-
 /* The 'mapping' part of i915_gem_object_pin_map() below */
 static void *i915_gem_object_map_page(struct drm_i915_gem_object *obj,
                                      enum i915_map_type type)
@@ -371,9 +352,7 @@ void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj,
            !i915_gem_object_type_has(obj, I915_GEM_OBJECT_HAS_IOMEM))
                return ERR_PTR(-ENXIO);
 
-       err = mutex_lock_interruptible(&obj->mm.lock);
-       if (err)
-               return ERR_PTR(err);
+       assert_object_held(obj);
 
        pinned = !(type & I915_MAP_OVERRIDE);
        type &= ~I915_MAP_OVERRIDE;
@@ -383,10 +362,8 @@ void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj,
                        GEM_BUG_ON(i915_gem_object_has_pinned_pages(obj));
 
                        err = ____i915_gem_object_get_pages(obj);
-                       if (err) {
-                               ptr = ERR_PTR(err);
-                               goto out_unlock;
-                       }
+                       if (err)
+                               return ERR_PTR(err);
 
                        smp_mb__before_atomic();
                }
@@ -421,13 +398,11 @@ void *i915_gem_object_pin_map(struct drm_i915_gem_object *obj,
                obj->mm.mapping = page_pack_bits(ptr, type);
        }
 
-out_unlock:
-       mutex_unlock(&obj->mm.lock);
        return ptr;
 
 err_unpin:
        atomic_dec(&obj->mm.pages_pin_count);
-       goto out_unlock;
+       return ptr;
 }
 
 void *i915_gem_object_pin_map_unlocked(struct drm_i915_gem_object *obj,

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_phys.c b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
index 92297362fad80ab57481c716b00477ba4568de48..81dc2bf59bc33a9371d3ba19c8275533317564c6 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_phys.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
@@ -234,40 +234,22 @@ int i915_gem_object_attach_phys(struct drm_i915_gem_object *obj, int align)
        if (err)
                return err;
 
-       err = mutex_lock_interruptible(&obj->mm.lock);
-       if (err)
-               return err;
-
-       if (unlikely(!i915_gem_object_has_struct_page(obj)))
-               goto out;
-
-       if (obj->mm.madv != I915_MADV_WILLNEED) {
-               err = -EFAULT;
-               goto out;
-       }
+       if (obj->mm.madv != I915_MADV_WILLNEED)
+               return -EFAULT;
 
-       if (i915_gem_object_has_tiling_quirk(obj)) {
-               err = -EFAULT;
-               goto out;
-       }
+       if (i915_gem_object_has_tiling_quirk(obj))
+               return -EFAULT;
 
-       if (obj->mm.mapping || i915_gem_object_has_pinned_pages(obj)) {
-               err = -EBUSY;
-               goto out;
-       }
+       if (obj->mm.mapping || i915_gem_object_has_pinned_pages(obj))
+               return -EBUSY;
 
        if (unlikely(obj->mm.madv != I915_MADV_WILLNEED)) {
                drm_dbg(obj->base.dev,
                        "Attempting to obtain a purgeable object\n");
-               err = -EFAULT;
-               goto out;
+               return -EFAULT;
        }
 
-       err = i915_gem_object_shmem_to_phys(obj);
-
-out:
-       mutex_unlock(&obj->mm.lock);
-       return err;
+       return i915_gem_object_shmem_to_phys(obj);
 }
 
 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pm.c b/drivers/gpu/drm/i915/gem/i915_gem_pm.c
index 000e1cd8e9201d282ca23b78cd77365434ecc635..8b9d7d14c4bdad7877525b074f737186c3ccd07c 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_pm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_pm.c
@@ -116,7 +116,7 @@ int i915_gem_freeze_late(struct drm_i915_private *i915)
         */
 
        with_intel_runtime_pm(&i915->runtime_pm, wakeref)
-               i915_gem_shrink(i915, -1UL, NULL, ~0);
+               i915_gem_shrink(NULL, i915, -1UL, NULL, ~0);
        i915_gem_drain_freed_objects(i915);
 
        wbinvd_on_all_cpus();

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
index 59fb16a822705517b49e776fea90f586af8169cb..a9bfa66c8da1c0b63da1ca392ff93e6b9b5d8536 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c
@@ -99,7 +99,7 @@ rebuild_st:
                                goto err_sg;
                        }
 
-                       i915_gem_shrink(i915, 2 * page_count, NULL, *s++);
+                       i915_gem_shrink(NULL, i915, 2 * page_count, NULL, *s++);
 
                        /*
                         * We've tried hard to allocate the memory by reaping

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
index 11b8d4e69fc71e6e8882a6270376444099968487..3e248d3bd869b4ef8decd4ede84f6bcba6a447b5 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.c
@@ -94,7 +94,8 @@ static void try_to_writeback(struct drm_i915_gem_object *obj,
  * The number of pages of backing storage actually released.
  */
 unsigned long
-i915_gem_shrink(struct drm_i915_private *i915,
+i915_gem_shrink(struct i915_gem_ww_ctx *ww,
+               struct drm_i915_private *i915,
                unsigned long target,
                unsigned long *nr_scanned,
                unsigned int shrink)
@@ -113,6 +114,7 @@ i915_gem_shrink(struct drm_i915_private *i915,
        intel_wakeref_t wakeref = 0;
        unsigned long count = 0;
        unsigned long scanned = 0;
+       int err;
 
        trace_i915_gem_shrink(i915, target, shrink);
 
@@ -200,25 +202,40 @@ i915_gem_shrink(struct drm_i915_private *i915,
 
                        spin_unlock_irqrestore(&i915->mm.obj_lock, flags);
 
-                       if (unsafe_drop_pages(obj, shrink) &&
-                           mutex_trylock(&obj->mm.lock)) {
+                       err = 0;
+                       if (unsafe_drop_pages(obj, shrink)) {
                                /* May arrive from get_pages on another bo */
-                               if (!__i915_gem_object_put_pages_locked(obj)) {
+                               if (!ww) {
+                                       if (!i915_gem_object_trylock(obj))
+                                               goto skip;
+                               } else {
+                                       err = i915_gem_object_lock(obj, ww);
+                                       if (err)
+                                               goto skip;
+                               }
+
+                               if (!__i915_gem_object_put_pages(obj)) {
                                        try_to_writeback(obj, shrink);
                                        count += obj->base.size >> PAGE_SHIFT;
                                }
-                               mutex_unlock(&obj->mm.lock);
+                               if (!ww)
+                                       i915_gem_object_unlock(obj);
                        }
 
                        dma_resv_prune(obj->base.resv);
 
                        scanned += obj->base.size >> PAGE_SHIFT;
+skip:
                        i915_gem_object_put(obj);
 
                        spin_lock_irqsave(&i915->mm.obj_lock, flags);
+                       if (err)
+                               break;
                }
                list_splice_tail(&still_in_list, phase->list);
                spin_unlock_irqrestore(&i915->mm.obj_lock, flags);
+               if (err)
+                       return err;
        }
 
        if (shrink & I915_SHRINK_BOUND)
@@ -249,7 +266,7 @@ unsigned long i915_gem_shrink_all(struct drm_i915_private *i915)
        unsigned long freed = 0;
 
        with_intel_runtime_pm(&i915->runtime_pm, wakeref) {
-               freed = i915_gem_shrink(i915, -1UL, NULL,
+               freed = i915_gem_shrink(NULL, i915, -1UL, NULL,
                                        I915_SHRINK_BOUND |
                                        I915_SHRINK_UNBOUND);
        }
@@ -295,7 +312,7 @@ i915_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
 
        sc->nr_scanned = 0;
 
-       freed = i915_gem_shrink(i915,
+       freed = i915_gem_shrink(NULL, i915,
                                sc->nr_to_scan,
                                &sc->nr_scanned,
                                I915_SHRINK_BOUND |
@@ -304,7 +321,7 @@ i915_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
                intel_wakeref_t wakeref;
 
                with_intel_runtime_pm(&i915->runtime_pm, wakeref) {
-                       freed += i915_gem_shrink(i915,
+                       freed += i915_gem_shrink(NULL, i915,
                                                 sc->nr_to_scan - sc->nr_scanned,
                                                 &sc->nr_scanned,
                                                 I915_SHRINK_ACTIVE |
@@ -329,7 +346,7 @@ i915_gem_shrinker_oom(struct notifier_block *nb, unsigned long event, void *ptr)
 
        freed_pages = 0;
        with_intel_runtime_pm(&i915->runtime_pm, wakeref)
-               freed_pages += i915_gem_shrink(i915, -1UL, NULL,
+               freed_pages += i915_gem_shrink(NULL, i915, -1UL, NULL,
                                               I915_SHRINK_BOUND |
                                               I915_SHRINK_UNBOUND |
                                               I915_SHRINK_WRITEBACK);
@@ -367,7 +384,7 @@ i915_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr
        intel_wakeref_t wakeref;
 
        with_intel_runtime_pm(&i915->runtime_pm, wakeref)
-               freed_pages += i915_gem_shrink(i915, -1UL, NULL,
+               freed_pages += i915_gem_shrink(NULL, i915, -1UL, NULL,
                                               I915_SHRINK_BOUND |
                                               I915_SHRINK_UNBOUND |
                                               I915_SHRINK_VMAPS);

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.h b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.h
index b397d7785789a1167eb2de905f1712ba1831624b..8512470f6fd6ba80f79b5994df8b90b6175b4b56 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_shrinker.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_shrinker.h
@@ -9,10 +9,12 @@
 #include <linux/bits.h>
 
 struct drm_i915_private;
+struct i915_gem_ww_ctx;
 struct mutex;
 
 /* i915_gem_shrinker.c */
-unsigned long i915_gem_shrink(struct drm_i915_private *i915,
+unsigned long i915_gem_shrink(struct i915_gem_ww_ctx *ww,
+                             struct drm_i915_private *i915,
                              unsigned long target,
                              unsigned long *nr_scanned,
                              unsigned flags);

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_tiling.c b/drivers/gpu/drm/i915/gem/i915_gem_tiling.c
index d589d3d81085dc4c1e524708d412e533fbbe01dc..9e89450130900983611431c51442b2a0b7f59d57 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_tiling.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_tiling.c
@@ -265,7 +265,6 @@ i915_gem_object_set_tiling(struct drm_i915_gem_object *obj,
         * pages to prevent them being swapped out and causing corruption
         * due to the change in swizzling.
         */
-       mutex_lock(&obj->mm.lock);
        if (i915_gem_object_has_pages(obj) &&
            obj->mm.madv == I915_MADV_WILLNEED &&
            i915->quirks & QUIRK_PIN_SWIZZLED_PAGES) {
@@ -280,7 +279,6 @@ i915_gem_object_set_tiling(struct drm_i915_gem_object *obj,
                        i915_gem_object_set_tiling_quirk(obj);
                }
        }
-       mutex_unlock(&obj->mm.lock);
 
        spin_lock(&obj->vma.lock);
        for_each_ggtt_vma(vma, obj) {

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
index f9209ebe27e4ce34bd0a3c1c806449038f31765d..4afd08c1fe097132a96443ef0204b25c778574b2 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
@@ -253,7 +253,7 @@ static int i915_gem_object_userptr_unbind(struct drm_i915_gem_object *obj, bool
        if (GEM_WARN_ON(i915_gem_object_has_pinned_pages(obj)))
                return -EBUSY;
 
-       mutex_lock(&obj->mm.lock);
+       assert_object_held(obj);
 
        pages = __i915_gem_object_unset_pages(obj);
        if (!IS_ERR_OR_NULL(pages))
@@ -261,7 +261,6 @@ static int i915_gem_object_userptr_unbind(struct drm_i915_gem_object *obj, bool
 
        if (get_pages)
                err = ____i915_gem_object_get_pages(obj);
-       mutex_unlock(&obj->mm.lock);
 
        return err;
 }

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 51133b8fabb4d225eacadbef78f69df1e4d2d319..b00c828f90a7ff8f3631f4dba951cfff0a7dd58d 100644 (file)
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -904,10 +904,10 @@ i915_drop_caches_set(void *data, u64 val)
 
        fs_reclaim_acquire(GFP_KERNEL);
        if (val & DROP_BOUND)
-               i915_gem_shrink(i915, LONG_MAX, NULL, I915_SHRINK_BOUND);
+               i915_gem_shrink(NULL, i915, LONG_MAX, NULL, I915_SHRINK_BOUND);
 
        if (val & DROP_UNBOUND)
-               i915_gem_shrink(i915, LONG_MAX, NULL, I915_SHRINK_UNBOUND);
+               i915_gem_shrink(NULL, i915, LONG_MAX, NULL, I915_SHRINK_UNBOUND);
 
        if (val & DROP_SHRINK_ALL)
                i915_gem_shrink_all(i915);

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 8027cb316d4b0681ec65f4611c69a6399a179030..b23f58e94cfb702a0ce41608ef6cc7a2d2692773 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -980,10 +980,6 @@ i915_gem_madvise_ioctl(struct drm_device *dev, void *data,
        if (err)
                goto out;
 
-       err = mutex_lock_interruptible(&obj->mm.lock);
-       if (err)
-               goto out_ww;
-
        if (i915_gem_object_has_pages(obj) &&
            i915_gem_object_is_tiled(obj) &&
            i915->quirks & QUIRK_PIN_SWIZZLED_PAGES) {
@@ -1026,9 +1022,7 @@ i915_gem_madvise_ioctl(struct drm_device *dev, void *data,
                i915_gem_object_truncate(obj);
 
        args->retained = obj->mm.madv != __I915_MADV_PURGED;
-       mutex_unlock(&obj->mm.lock);
 
-out_ww:
        i915_gem_object_unlock(obj);
 out:
        i915_gem_object_put(obj);

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 486c9953e5b65b4981b5bdff0a86eeac378db531..36489be4896b579052dab635e0bb7192004d017c 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -44,7 +44,7 @@ int i915_gem_gtt_prepare_pages(struct drm_i915_gem_object *obj,
                 * the DMA remapper, i915_gem_shrink will return 0.
                 */
                GEM_BUG_ON(obj->mm.pages == pages);
-       } while (i915_gem_shrink(to_i915(obj->base.dev),
+       } while (i915_gem_shrink(NULL, to_i915(obj->base.dev),
                                 obj->base.size >> PAGE_SHIFT, NULL,
                                 I915_SHRINK_BOUND |
                                 I915_SHRINK_UNBOUND));