[Intel-gfx] [RFC PATCH v3 07/17] drm/i915/vm_bind: Handle persistent vmas

Andi Shyti
2022-08-27T19:46:08Z

From: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>

Treat VM_BIND vmas as persistent across execbuf ioctl calls and handle
them during the request submission in the execbuff path.

Support eviction by maintaining a list of evicted persistent vmas
for rebinding during next submission.

Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_object.c | 1 +
.../drm/i915/gem/i915_gem_vm_bind_object.c | 8 +++
drivers/gpu/drm/i915/gt/intel_gtt.c | 2 +
drivers/gpu/drm/i915/gt/intel_gtt.h | 4 ++
drivers/gpu/drm/i915/i915_gem_gtt.c | 38 +++++++++++++
drivers/gpu/drm/i915/i915_gem_gtt.h | 3 +
drivers/gpu/drm/i915/i915_vma.c | 50 +++++++++++++++--
drivers/gpu/drm/i915/i915_vma.h | 56 +++++++++++++++----
drivers/gpu/drm/i915/i915_vma_types.h | 24 ++++++++
9 files changed, 169 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c
index 389e9f157ca5e..825dce41f7113 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c
@@ -38,6 +38,7 @@
#include "i915_gem_mman.h"
#include "i915_gem_object.h"
#include "i915_gem_ttm.h"
+#include "i915_gem_vm_bind.h"
#include "i915_memcpy.h"
#include "i915_trace.h"

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_vm_bind_object.c b/drivers/gpu/drm/i915/gem/i915_gem_vm_bind_object.c
index 9ff929f187cfd..3b45529fe8d4c 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_vm_bind_object.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_vm_bind_object.c
@@ -91,6 +91,13 @@ void i915_gem_vm_bind_remove(struct i915_vma *vma, bool release_obj)
{
lockdep_assert_held(&vma->vm->vm_bind_lock);

+ spin_lock(&vma->vm->vm_rebind_lock);
+ if (!list_empty(&vma->vm_rebind_link))
+ list_del_init(&vma->vm_rebind_link);
+ i915_vma_set_purged(vma);
+ i915_vma_set_freed(vma);
+ spin_unlock(&vma->vm->vm_rebind_lock);
+
if (!list_empty(&vma->vm_bind_link)) {
list_del_init(&vma->vm_bind_link);
list_del_init(&vma->non_priv_vm_bind_link);
@@ -190,6 +197,7 @@ static struct i915_vma *vm_bind_get_vma(struct i915_address_space *vm,

vma->start = va->start;
vma->last = va->start + va->length - 1;
+ i915_vma_set_persistent(vma);

return vma;
}
diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.c b/drivers/gpu/drm/i915/gt/intel_gtt.c
index c4f75826213ae..97cd0089b516d 100644
--- a/drivers/gpu/drm/i915/gt/intel_gtt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gtt.c
@@ -296,6 +296,8 @@ void i915_address_space_init(struct i915_address_space *vm, int subclass)
INIT_LIST_HEAD(&vm->non_priv_vm_bind_list);
vm->root_obj = i915_gem_object_create_internal(vm->i915, PAGE_SIZE);
GEM_BUG_ON(IS_ERR(vm->root_obj));
+ INIT_LIST_HEAD(&vm->vm_rebind_list);
+ spin_lock_init(&vm->vm_rebind_lock);
}

void *__px_vaddr(struct drm_i915_gem_object *p)
diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.h b/drivers/gpu/drm/i915/gt/intel_gtt.h
index 9a2665e4ec2e5..1f3b1967ec175 100644
--- a/drivers/gpu/drm/i915/gt/intel_gtt.h
+++ b/drivers/gpu/drm/i915/gt/intel_gtt.h
@@ -265,6 +265,10 @@ struct i915_address_space {
struct list_head vm_bind_list;
/** @vm_bound_list: List of vm_binding completed */
struct list_head vm_bound_list;
+ /* @vm_rebind_list: list of vmas to be rebinded */
+ struct list_head vm_rebind_list;
+ /* @vm_rebind_lock: protects vm_rebound_list */
+ spinlock_t vm_rebind_lock;
/* @va: tree of persistent vmas */
struct rb_root_cached va;
struct list_head non_priv_vm_bind_list;
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 329ff75b80b97..f083724163deb 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -25,6 +25,44 @@
#include "i915_trace.h"
#include "i915_vgpu.h"

+/**
+ * i915_vm_sync() - Wait for all requests on private vmas of a vm to be completed
+ * @vm: address space we need to wait for idle
+ *
+ * Waits till all requests of the vm_binded private objs are completed.
+ *
+ * Returns: 0 on success -ve errcode on failure
+ */
+int i915_vm_sync(struct i915_address_space *vm)
+{
+ int ret;
+
+ /* Wait for all requests under this vm to finish */
+ ret = dma_resv_wait_timeout(vm->root_obj->base.resv,
+ DMA_RESV_USAGE_BOOKKEEP, false,
+ MAX_SCHEDULE_TIMEOUT);
+ if (ret < 0)
+ return ret;
+ else if (ret > 0)
+ return 0;
+ else
+ return -ETIMEDOUT;
+}
+
+/**
+ * i915_vm_is_active() - Check for activeness of requests of vm
+ * @vm: address spece targetted
+ *
+ * Check whether all the requests related private vmas are completed or not
+ *
+ * Returns: True when requests are not completed yet. Flase otherwise.
+ */
+bool i915_vm_is_active(const struct i915_address_space *vm)
+{
+ return !dma_resv_test_signaled(vm->root_obj->base.resv,
+ DMA_RESV_USAGE_BOOKKEEP);
+}
+
int i915_gem_gtt_prepare_pages(struct drm_i915_gem_object *obj,
struct sg_table *pages)
{
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h
index 8c2f57eb5ddaa..a5bbdc59d9dfb 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -51,4 +51,7 @@ int i915_gem_gtt_insert(struct i915_address_space *vm,

#define PIN_OFFSET_MASK I915_GTT_PAGE_MASK

+int i915_vm_sync(struct i915_address_space *vm);
+bool i915_vm_is_active(const struct i915_address_space *vm);
+
#endif
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index 239346e0c07f2..0eb7727d62a6f 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -237,6 +237,7 @@ vma_create(struct drm_i915_gem_object *obj,

INIT_LIST_HEAD(&vma->vm_bind_link);
INIT_LIST_HEAD(&vma->non_priv_vm_bind_link);
+ INIT_LIST_HEAD(&vma->vm_rebind_link);
return vma;

err_unlock:
@@ -387,8 +388,31 @@ int i915_vma_wait_for_bind(struct i915_vma *vma)
return err;
}

-#if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
-static int i915_vma_verify_bind_complete(struct i915_vma *vma)
+/**
+ * i915_vma_sync() - Wait for the vma to be idle
+ * @vma: vma to be tested
+ *
+ * Returns 0 on success and error code on failure
+ */
+int i915_vma_sync(struct i915_vma *vma)
+{
+ int ret;
+
+ /* Wait for the asynchronous bindings and pending GPU reads */
+ ret = i915_active_wait(&vma->active);
+ if (ret || !i915_vma_is_persistent(vma) || i915_vma_is_purged(vma))
+ return ret;
+
+ return i915_vm_sync(vma->vm);
+}
+
+/**
+ * i915_vma_verify_bind_complete() - Check for the vm_bind completion of the vma
+ * @vma: vma submitted for vm_bind
+ *
+ * Returns: 0 if the vm_bind is completed. Error code otherwise.
+ */
+int i915_vma_verify_bind_complete(struct i915_vma *vma)
{
struct dma_fence *fence = i915_active_fence_get(&vma->active.excl);
int err;
@@ -405,9 +429,6 @@ static int i915_vma_verify_bind_complete(struct i915_vma *vma)

return err;
}
-#else
-#define i915_vma_verify_bind_complete(_vma) 0
-#endif

I915_SELFTEST_EXPORT void
i915_vma_resource_init_from_vma(struct i915_vma_resource *vma_res,
@@ -1654,6 +1675,13 @@ static void force_unbind(struct i915_vma *vma)
if (!drm_mm_node_allocated(&vma->node))
return;

+ /*
+ * Mark persistent vma as purged to avoid it waiting
+ * for VM to be released.
+ */
+ if (i915_vma_is_persistent(vma))
+ i915_vma_set_purged(vma);
+
atomic_and(~I915_VMA_PIN_MASK, &vma->flags);
WARN_ON(__i915_vma_unbind(vma));
GEM_BUG_ON(drm_mm_node_allocated(&vma->node));
@@ -1846,6 +1874,8 @@ int _i915_vma_move_to_active(struct i915_vma *vma,
int err;

assert_object_held(obj);
+ if (i915_vma_is_persistent(vma))
+ return -EINVAL;

GEM_BUG_ON(!vma->pages);

@@ -2014,6 +2044,16 @@ int __i915_vma_unbind(struct i915_vma *vma)
__i915_vma_evict(vma, false);

drm_mm_remove_node(&vma->node); /* pairs with i915_vma_release() */
+
+ if (i915_vma_is_persistent(vma)) {
+ spin_lock(&vma->vm->vm_rebind_lock);
+ if (list_empty(&vma->vm_rebind_link) &&
+ !i915_vma_is_purged(vma))
+ list_add_tail(&vma->vm_rebind_link,
+ &vma->vm->vm_rebind_list);
+ spin_unlock(&vma->vm->vm_rebind_lock);
+ }
+
return 0;
}

diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 15eac55a3e274..bf0b5b4abd919 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -47,12 +47,6 @@ i915_vma_instance(struct drm_i915_gem_object *obj,

void i915_vma_unpin_and_release(struct i915_vma **p_vma, unsigned int flags);
#define I915_VMA_RELEASE_MAP BIT(0)
-
-static inline bool i915_vma_is_active(const struct i915_vma *vma)
-{
- return !i915_active_is_idle(&vma->active);
-}
-
/* do not reserve memory to prevent deadlocks */
#define __EXEC_OBJECT_NO_RESERVE BIT(31)

@@ -138,6 +132,48 @@ static inline u32 i915_ggtt_pin_bias(struct i915_vma *vma)
return i915_vm_to_ggtt(vma->vm)->pin_bias;
}

+static inline bool i915_vma_is_persistent(const struct i915_vma *vma)
+{
+ return test_bit(I915_VMA_PERSISTENT_BIT, __i915_vma_flags(vma));
+}
+
+static inline void i915_vma_set_persistent(struct i915_vma *vma)
+{
+ set_bit(I915_VMA_PERSISTENT_BIT, __i915_vma_flags(vma));
+}
+
+static inline bool i915_vma_is_purged(const struct i915_vma *vma)
+{
+ return test_bit(I915_VMA_PURGED_BIT, __i915_vma_flags(vma));
+}
+
+static inline void i915_vma_set_purged(struct i915_vma *vma)
+{
+ set_bit(I915_VMA_PURGED_BIT, __i915_vma_flags(vma));
+}
+
+static inline bool i915_vma_is_freed(const struct i915_vma *vma)
+{
+ return test_bit(I915_VMA_FREED_BIT, __i915_vma_flags(vma));
+}
+
+static inline void i915_vma_set_freed(struct i915_vma *vma)
+{
+ set_bit(I915_VMA_FREED_BIT, __i915_vma_flags(vma));
+}
+
+static inline bool i915_vma_is_active(const struct i915_vma *vma)
+{
+ if (i915_vma_is_persistent(vma)) {
+ if (i915_vma_is_purged(vma))
+ return false;
+
+ return i915_vm_is_active(vma->vm);
+ }
+
+ return !i915_active_is_idle(&vma->active);
+}
+
static inline struct i915_vma *i915_vma_get(struct i915_vma *vma)
{
i915_gem_object_get(vma->obj);
@@ -406,12 +442,8 @@ void i915_vma_make_shrinkable(struct i915_vma *vma);
void i915_vma_make_purgeable(struct i915_vma *vma);

int i915_vma_wait_for_bind(struct i915_vma *vma);
-
-static inline int i915_vma_sync(struct i915_vma *vma)
-{
- /* Wait for the asynchronous bindings and pending GPU reads */
- return i915_active_wait(&vma->active);
-}
+int i915_vma_verify_bind_complete(struct i915_vma *vma);
+int i915_vma_sync(struct i915_vma *vma);

/**
* i915_vma_get_current_resource - Get the current resource of the vma
diff --git a/drivers/gpu/drm/i915/i915_vma_types.h b/drivers/gpu/drm/i915/i915_vma_types.h
index de5534d518cdd..5483ccf0c82c7 100644
--- a/drivers/gpu/drm/i915/i915_vma_types.h
+++ b/drivers/gpu/drm/i915/i915_vma_types.h
@@ -264,6 +264,28 @@ struct i915_vma {
#define I915_VMA_SCANOUT_BIT 17
#define I915_VMA_SCANOUT ((int)BIT(I915_VMA_SCANOUT_BIT))

+ /**
+ * I915_VMA_PERSISTENT_BIT:
+ * The vma is persistent (created with VM_BIND call).
+ *
+ * I915_VMA_PURGED_BIT:
+ * The persistent vma is force unbound either due to VM_UNBIND call
+ * from UMD or VM is released. Do not check/wait for VM activeness
+ * in i915_vma_is_active() and i915_vma_sync() calls.
+ *
+ * I915_VMA_FREED_BIT:
+ * The persistent vma is being released by UMD via VM_UNBIND call.
+ * While releasing the vma, do not take VM_BIND lock as VM_UNBIND call
+ * already holds the lock.
+ */
+#define I915_VMA_PERSISTENT_BIT 19
+#define I915_VMA_PURGED_BIT 20
+#define I915_VMA_FREED_BIT 21
+
+#define I915_VMA_PERSISTENT ((int)BIT(I915_VMA_PERSISTENT_BIT))
+#define I915_VMA_PURGED ((int)BIT(I915_VMA_PURGED_BIT))
+#define I915_VMA_FREED ((int)BIT(I915_VMA_FREED_BIT))
+
struct i915_active active;

#define I915_VMA_PAGES_BIAS 24
@@ -293,6 +315,8 @@ struct i915_vma {
struct list_head vm_bind_link;
/* @non_priv_vm_bind_link: Link in non-private persistent VMA list */
struct list_head non_priv_vm_bind_link;
+ /* @vm_rebind_link: link to vm_rebind_list and protected by vm_rebind_lock */
+ struct list_head vm_rebind_link; /* Link in vm_rebind_list */

/** Interval tree structures for persistent vma */

--
2.34.1