[Intel-gfx] [RFC v4 06/14] drm/i915/vm_bind: Handle persistent vmas
Niranjana Vishwanathapura
niranjana.vishwanathapura at intel.com
Tue Sep 27 05:45:58 UTC 2022
On Mon, Sep 26, 2022 at 07:36:24PM -0700, Zeng, Oak wrote:
>
>
>Regards,
>Oak
>
>> -----Original Message-----
>> From: Intel-gfx <intel-gfx-bounces at lists.freedesktop.org> On Behalf Of Niranjana
>> Vishwanathapura
>> Sent: September 21, 2022 3:10 AM
>> To: intel-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org
>> Cc: Zanoni, Paulo R <paulo.r.zanoni at intel.com>; Hellstrom, Thomas
>> <thomas.hellstrom at intel.com>; Auld, Matthew <matthew.auld at intel.com>; Vetter,
>> Daniel <daniel.vetter at intel.com>; christian.koenig at amd.com
>> Subject: [Intel-gfx] [RFC v4 06/14] drm/i915/vm_bind: Handle persistent vmas
>>
>> 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 at intel.com>
>> Signed-off-by: Andi Shyti <andi.shyti at linux.intel.com>
>> ---
>> .../drm/i915/gem/i915_gem_vm_bind_object.c | 7 +++
>> 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 | 39 ++++++++++++++++
>> drivers/gpu/drm/i915/i915_gem_gtt.h | 3 ++
>> drivers/gpu/drm/i915/i915_vma.c | 46 +++++++++++++++++++
>> drivers/gpu/drm/i915/i915_vma.h | 45 +++++++++++++-----
>> drivers/gpu/drm/i915/i915_vma_types.h | 17 +++++++
>> 8 files changed, 151 insertions(+), 12 deletions(-)
>>
>> 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 7ca6a41fc981..236f901b8b9c 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 +91,12 @@ static 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);
>> + spin_unlock(&vma->vm->vm_rebind_lock);
>> +
>> list_del_init(&vma->vm_bind_link);
>> list_del_init(&vma->non_priv_vm_bind_link);
>> i915_vm_bind_it_remove(vma, &vma->vm->va);
>> @@ -181,6 +187,7 @@ 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 da4f9dee0397..6db31197fa87 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 3f2e87d3bf34..b73d35b4e05d 100644
>> --- a/drivers/gpu/drm/i915/gt/intel_gtt.h
>> +++ b/drivers/gpu/drm/i915/gt/intel_gtt.h
>> @@ -273,6 +273,10 @@ 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 329ff75b80b9..b7d0844de561 100644
>> --- a/drivers/gpu/drm/i915/i915_gem_gtt.c
>> +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
>> @@ -25,6 +25,45 @@
>> #include "i915_trace.h"
>> #include "i915_vgpu.h"
>>
>> +/**
>> + * i915_vm_sync() - Wait until address space is not in use
>> + * @vm: address space
>> + *
>> + * Waits until all requests using the address space are complete.
>> + *
>> + * Returns: 0 if success, -ve err code upon 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 if address space is being used
>> + * @vm: address space
>> + *
>> + * Check if any request using the specified address space is
>> + * active.
>> + *
>> + * Returns: true if address space is active, false 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 8c2f57eb5dda..a5bbdc59d9df 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 aa332ad69ec2..ff216e9a2c8d 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:
>> @@ -387,6 +388,24 @@ int i915_vma_wait_for_bind(struct i915_vma *vma)
>> return err;
>> }
>>
>> +/**
>> + * 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);
>
>Hi, I try to understand why we call vm_sync here. As I understand it, each vm has many vmas. The vma_sync function wait for a single vma to be idle, for example, wait for all the request/gpu task using this vma to complete. While vm_sync wait for the whole vm to be idle. To me vm_sync essentially wait for all the vmas in this vm to be idle. Isn't it?
>
Yah. But a persistent vma is active as long as the VM is active (also checkout i915_vma_is_active()). Hence we call i915_vm_sync() here.
I am rearranging the patches a bit and this part will go into a separate patch with more description. Hope that will help.
Regards,
Niranjana
>Thanks,
>Oak
>
>> +}
>> +
>> #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
>> static int i915_vma_verify_bind_complete(struct i915_vma *vma)
>> {
>> @@ -1654,6 +1673,13 @@ 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 +1872,8 @@ 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);
>>
>> @@ -2015,6 +2043,16 @@ 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;
>> }
>>
>> @@ -2046,6 +2084,14 @@ static struct dma_fence
>> *__i915_vma_unbind_async(struct i915_vma *vma)
>> return ERR_PTR(-EBUSY);
>> }
>>
>> + if (__i915_sw_fence_await_reservation(&vma->resource->chain,
>> + vma->obj->base.resv,
>> + DMA_RESV_USAGE_BOOKKEEP,
>> + i915_fence_timeout(vma->vm->i915),
>> + I915_FENCE_GFP) < 0) {
>> + return ERR_PTR(-EBUSY);
>> + }
>> +
>> fence = __i915_vma_evict(vma, true);
>>
>> drm_mm_remove_node(&vma->node); /* pairs with i915_vma_release() */
>> diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
>> index 6feef0305fe1..aa536c9ce472 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 +132,38 @@ 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_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 +432,7 @@ 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_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 6d727c2d9802..d21bf97febaa 100644
>> --- a/drivers/gpu/drm/i915/i915_vma_types.h
>> +++ b/drivers/gpu/drm/i915/i915_vma_types.h
>> @@ -264,6 +264,21 @@ 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.
>> + */
>> +#define I915_VMA_PERSISTENT_BIT 19
>> +#define I915_VMA_PURGED_BIT 20
>> +
>> +#define I915_VMA_PERSISTENT ((int)BIT(I915_VMA_PERSISTENT_BIT))
>> +#define I915_VMA_PURGED ((int)BIT(I915_VMA_PURGED_BIT))
>> +
>> struct i915_active active;
>>
>> #define I915_VMA_PAGES_BIAS 24
>> @@ -293,6 +308,8 @@ 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 */
>>
>> --
>> 2.21.0.rc0.32.g243a4c7e27
>
More information about the Intel-gfx
mailing list