Re: [PATCH v5 1/7] drm/amdgpu: pass all the sdma scheds to amdgpu_mman

[Pierre-Eric Pelloux-Prayer]

Le 07/04/2026 à 10:07, Christian König a écrit :

On 4/3/26 17:08, Alex Deucher wrote:

On Fri, Apr 3, 2026 at 4:36 AM Pierre-Eric Pelloux-Prayer
<pierre-eric.pelloux-pra...@amd.com> wrote:

This will allow the use of all of them for clear/fill buffer
operations.
Since drm_sched_entity_init requires a scheduler array, we
store schedulers rather than rings. For the few places that need
access to a ring, we can get it from the sched using container_of.

Since the code is the same for all sdma versions, add a new
helper amdgpu_sdma_set_buffer_funcs_scheds to set buffer_funcs_scheds
based on the number of sdma instances.

Note: the new sched array is identical to the amdgpu_vm_manager one.
These 2 could be merged.

Signed-off-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-pra...@amd.com>
Acked-by: Felix Kuehling <felix.kuehl...@amd.com>
---
  drivers/gpu/drm/amd/amdgpu/amdgpu.h        |  2 ++
  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |  2 +-
  drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c    |  4 ++-
  drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c    | 32 ++++++++++++++++++----
  drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h    |  3 +-
  drivers/gpu/drm/amd/amdgpu/cik_sdma.c      |  3 +-
  drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c     |  3 +-
  drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c     |  3 +-
  drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c     |  8 ++----
  drivers/gpu/drm/amd/amdgpu/sdma_v4_4_2.c   |  6 +---
  drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c     |  5 +---
  drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c     |  5 +---
  drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c     |  3 +-
  drivers/gpu/drm/amd/amdgpu/sdma_v7_0.c     |  3 +-
  drivers/gpu/drm/amd/amdgpu/sdma_v7_1.c     |  3 +-
  drivers/gpu/drm/amd/amdgpu/si_dma.c        |  3 +-
  drivers/gpu/drm/amd/amdkfd/kfd_migrate.c   |  3 +-
  17 files changed, 48 insertions(+), 43 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h 
b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 49e7881750fa..e3a8701f0b27 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -1467,6 +1467,8 @@ ssize_t amdgpu_get_soft_full_reset_mask(struct 
amdgpu_ring *ring);
  ssize_t amdgpu_show_reset_mask(char *buf, uint32_t supported_reset);
  void amdgpu_sdma_set_vm_pte_scheds(struct amdgpu_device *adev,
                                    const struct amdgpu_vm_pte_funcs 
*vm_pte_funcs);
+void amdgpu_sdma_set_buffer_funcs_scheds(struct amdgpu_device *adev,
+                                        const struct amdgpu_buffer_funcs 
*buffer_funcs);

  /* atpx handler */
  #if defined(CONFIG_VGA_SWITCHEROO)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 0c0489395edf..4da8de34be3d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -3700,7 +3700,7 @@ int amdgpu_device_init(struct amdgpu_device *adev,
         adev->num_rings = 0;
         RCU_INIT_POINTER(adev->gang_submit, dma_fence_get_stub());
         adev->mman.buffer_funcs = NULL;
-       adev->mman.buffer_funcs_ring = NULL;
+       adev->mman.num_buffer_funcs_scheds = 0;
         adev->vm_manager.vm_pte_funcs = NULL;
         adev->vm_manager.vm_pte_num_scheds = 0;
         adev->gmc.gmc_funcs = NULL;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
index e9e53c7c37d0..1a253e4257ff 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c
@@ -708,12 +708,14 @@ int amdgpu_gmc_allocate_vm_inv_eng(struct amdgpu_device 
*adev)
  void amdgpu_gmc_flush_gpu_tlb(struct amdgpu_device *adev, uint32_t vmid,
                               uint32_t vmhub, uint32_t flush_type)
  {
-       struct amdgpu_ring *ring = adev->mman.buffer_funcs_ring;
+       struct amdgpu_ring *ring;
         struct amdgpu_vmhub *hub = &adev->vmhub[vmhub];
         struct dma_fence *fence;
         struct amdgpu_job *job;
         int r;

+       ring = to_amdgpu_ring(adev->mman.buffer_funcs_scheds[0]);
+
         if (!hub->sdma_invalidation_workaround || vmid ||
             !adev->mman.buffer_funcs_enabled || !adev->ib_pool_ready ||
             !ring->sched.ready) {
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 3c63f87832e4..4ba7321b75e3 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -168,7 +168,7 @@ amdgpu_ttm_job_submit(struct amdgpu_device *adev, struct 
amdgpu_ttm_buffer_entit
  {
         struct amdgpu_ring *ring;

-       ring = adev->mman.buffer_funcs_ring;
+       ring = to_amdgpu_ring(adev->mman.buffer_funcs_scheds[0]);
         amdgpu_ring_pad_ib(ring, &job->ibs[0]);
         WARN_ON(job->ibs[0].length_dw > num_dw);

@@ -2349,18 +2349,17 @@ void amdgpu_ttm_set_buffer_funcs_status(struct 
amdgpu_device *adev, bool enable)
                 return;

         if (enable) {
-               struct amdgpu_ring *ring;
                 struct drm_gpu_scheduler *sched;

-               if (!adev->mman.buffer_funcs_ring || 
!adev->mman.buffer_funcs_ring->sched.ready) {
+               if (!adev->mman.num_buffer_funcs_scheds ||
+                   !adev->mman.buffer_funcs_scheds[0]->ready) {
                         dev_warn(adev->dev, "Not enabling DMA transfers for in 
kernel use");
                         return;
                 }

                 num_clear_entities = 1;
                 num_move_entities = 1;
-               ring = adev->mman.buffer_funcs_ring;
-               sched = &ring->sched;
+               sched = adev->mman.buffer_funcs_scheds[0];
                 r = amdgpu_ttm_buffer_entity_init(&adev->mman.gtt_mgr,
                                                   &adev->mman.default_entity,
                                                   DRM_SCHED_PRIORITY_KERNEL,
@@ -2497,7 +2496,7 @@ int amdgpu_copy_buffer(struct amdgpu_device *adev,
         unsigned int i;
         int r;

-       ring = adev->mman.buffer_funcs_ring;
+       ring = to_amdgpu_ring(adev->mman.buffer_funcs_scheds[0]);

         if (!ring->sched.ready) {
                 dev_err(adev->dev,
@@ -2730,6 +2729,27 @@ int amdgpu_ttm_evict_resources(struct amdgpu_device 
*adev, int mem_type)
         return ttm_resource_manager_evict_all(&adev->mman.bdev, man);
  }

+void amdgpu_sdma_set_buffer_funcs_scheds(struct amdgpu_device *adev,
+                                        const struct amdgpu_buffer_funcs 
*buffer_funcs)
+{
+       struct amdgpu_vmhub *hub = &adev->vmhub[AMDGPU_GFXHUB(0)];

Only gfx9 and newer have multiple hubs.  Additionally, sdma 4.x is
attached to mmhub.  sdma 5.x is attached to gfxhub.  Might be worth a
comment here that this is just for the sdma_invalidation_workaround
check so it's only relevant for specific chips that have that set in
case someone attempts to do something else here in the future.

IIRC this workaround only applies to Navi 1x and there the SDMA is connected to 
the gfxhub.

But I agree that this really needs at least a comment explaining why we do this.

I added a comment to v6 of this patch, thanks.

Pierre-Eric

Christian.

Alex

+       struct drm_gpu_scheduler *sched;
+       int i;
+
+       adev->mman.buffer_funcs = buffer_funcs;
+
+       for (i = 0; i < adev->sdma.num_instances; i++) {
+               if (adev->sdma.has_page_queue)
+                       sched = &adev->sdma.instance[i].page.sched;
+               else
+                       sched = &adev->sdma.instance[i].ring.sched;
+               adev->mman.buffer_funcs_scheds[i] = sched;
+       }
+
+       adev->mman.num_buffer_funcs_scheds = hub->sdma_invalidation_workaround ?
+               1 : adev->sdma.num_instances;
+}
+
  #if defined(CONFIG_DEBUG_FS)

  static int amdgpu_ttm_page_pool_show(struct seq_file *m, void *unused)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
index 3b1973611446..a6249252948b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
@@ -67,7 +67,8 @@ struct amdgpu_mman {

         /* buffer handling */
         const struct amdgpu_buffer_funcs        *buffer_funcs;
-       struct amdgpu_ring                      *buffer_funcs_ring;
+       struct drm_gpu_scheduler                
*buffer_funcs_scheds[AMDGPU_MAX_RINGS];
+       u32                                     num_buffer_funcs_scheds;
         bool                                    buffer_funcs_enabled;

         /* @default_entity: for workarounds, has no gart windows */
diff --git a/drivers/gpu/drm/amd/amdgpu/cik_sdma.c 
b/drivers/gpu/drm/amd/amdgpu/cik_sdma.c
index 22780c09177d..26276dcfd458 100644
--- a/drivers/gpu/drm/amd/amdgpu/cik_sdma.c
+++ b/drivers/gpu/drm/amd/amdgpu/cik_sdma.c
@@ -1340,8 +1340,7 @@ static const struct amdgpu_buffer_funcs 
cik_sdma_buffer_funcs = {

  static void cik_sdma_set_buffer_funcs(struct amdgpu_device *adev)
  {
-       adev->mman.buffer_funcs = &cik_sdma_buffer_funcs;
-       adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].ring;
+       amdgpu_sdma_set_buffer_funcs_scheds(adev, &cik_sdma_buffer_funcs);
  }

  const struct amdgpu_ip_block_version cik_sdma_ip_block =
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c 
b/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c
index 0090ace49024..c6a059ca59e5 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c
@@ -1235,8 +1235,7 @@ static const struct amdgpu_buffer_funcs 
sdma_v2_4_buffer_funcs = {

  static void sdma_v2_4_set_buffer_funcs(struct amdgpu_device *adev)
  {
-       adev->mman.buffer_funcs = &sdma_v2_4_buffer_funcs;
-       adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].ring;
+       amdgpu_sdma_set_buffer_funcs_scheds(adev, &sdma_v2_4_buffer_funcs);
  }

  const struct amdgpu_ip_block_version sdma_v2_4_ip_block = {
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c 
b/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c
index 2526d393162a..cb516a25210d 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c
@@ -1677,8 +1677,7 @@ static const struct amdgpu_buffer_funcs 
sdma_v3_0_buffer_funcs = {

  static void sdma_v3_0_set_buffer_funcs(struct amdgpu_device *adev)
  {
-       adev->mman.buffer_funcs = &sdma_v3_0_buffer_funcs;
-       adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].ring;
+       amdgpu_sdma_set_buffer_funcs_scheds(adev, &sdma_v3_0_buffer_funcs);
  }

  const struct amdgpu_ip_block_version sdma_v3_0_ip_block =
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c 
b/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
index 44f0f23e1148..d56be26f216b 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
@@ -2626,13 +2626,9 @@ static const struct amdgpu_buffer_funcs 
sdma_v4_4_buffer_funcs = {
  static void sdma_v4_0_set_buffer_funcs(struct amdgpu_device *adev)
  {
         if (amdgpu_ip_version(adev, SDMA0_HWIP, 0) >= IP_VERSION(4, 4, 0))
-               adev->mman.buffer_funcs = &sdma_v4_4_buffer_funcs;
+               amdgpu_sdma_set_buffer_funcs_scheds(adev, 
&sdma_v4_4_buffer_funcs);
         else
-               adev->mman.buffer_funcs = &sdma_v4_0_buffer_funcs;
-       if (adev->sdma.has_page_queue)
-               adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].page;
-       else
-               adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].ring;
+               amdgpu_sdma_set_buffer_funcs_scheds(adev, 
&sdma_v4_0_buffer_funcs);
  }

  static void sdma_v4_0_get_ras_error_count(uint32_t value,
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v4_4_2.c 
b/drivers/gpu/drm/amd/amdgpu/sdma_v4_4_2.c
index 78bdfed0a7fd..67e9697301b4 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v4_4_2.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v4_4_2.c
@@ -2316,11 +2316,7 @@ static const struct amdgpu_buffer_funcs 
sdma_v4_4_2_buffer_funcs = {

  static void sdma_v4_4_2_set_buffer_funcs(struct amdgpu_device *adev)
  {
-       adev->mman.buffer_funcs = &sdma_v4_4_2_buffer_funcs;
-       if (adev->sdma.has_page_queue)
-               adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].page;
-       else
-               adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].ring;
+       amdgpu_sdma_set_buffer_funcs_scheds(adev, &sdma_v4_4_2_buffer_funcs);
  }

  /**
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c 
b/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c
index 52f4e9e099cb..86f5eb784d57 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c
@@ -2052,10 +2052,7 @@ static const struct amdgpu_buffer_funcs 
sdma_v5_0_buffer_funcs = {

  static void sdma_v5_0_set_buffer_funcs(struct amdgpu_device *adev)
  {
-       if (adev->mman.buffer_funcs == NULL) {
-               adev->mman.buffer_funcs = &sdma_v5_0_buffer_funcs;
-               adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].ring;
-       }
+       amdgpu_sdma_set_buffer_funcs_scheds(adev, &sdma_v5_0_buffer_funcs);
  }

  const struct amdgpu_ip_block_version sdma_v5_0_ip_block = {
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c 
b/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c
index b4fb90cc8f7d..3fec838374b2 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c
@@ -2056,10 +2056,7 @@ static const struct amdgpu_buffer_funcs 
sdma_v5_2_buffer_funcs = {

  static void sdma_v5_2_set_buffer_funcs(struct amdgpu_device *adev)
  {
-       if (adev->mman.buffer_funcs == NULL) {
-               adev->mman.buffer_funcs = &sdma_v5_2_buffer_funcs;
-               adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].ring;
-       }
+       amdgpu_sdma_set_buffer_funcs_scheds(adev, &sdma_v5_2_buffer_funcs);
  }

  const struct amdgpu_ip_block_version sdma_v5_2_ip_block = {
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c 
b/drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c
index b005672f2f96..064508cecd11 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c
@@ -1895,8 +1895,7 @@ static const struct amdgpu_buffer_funcs 
sdma_v6_0_buffer_funcs = {

  static void sdma_v6_0_set_buffer_funcs(struct amdgpu_device *adev)
  {
-       adev->mman.buffer_funcs = &sdma_v6_0_buffer_funcs;
-       adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].ring;
+       amdgpu_sdma_set_buffer_funcs_scheds(adev, &sdma_v6_0_buffer_funcs);
  }

  const struct amdgpu_ip_block_version sdma_v6_0_ip_block = {
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v7_0.c 
b/drivers/gpu/drm/amd/amdgpu/sdma_v7_0.c
index 5679a94d0815..60447729271e 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v7_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v7_0.c
@@ -1845,8 +1845,7 @@ static const struct amdgpu_buffer_funcs 
sdma_v7_0_buffer_funcs = {

  static void sdma_v7_0_set_buffer_funcs(struct amdgpu_device *adev)
  {
-       adev->mman.buffer_funcs = &sdma_v7_0_buffer_funcs;
-       adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].ring;
+       amdgpu_sdma_set_buffer_funcs_scheds(adev, &sdma_v7_0_buffer_funcs);
  }

  const struct amdgpu_ip_block_version sdma_v7_0_ip_block = {
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v7_1.c 
b/drivers/gpu/drm/amd/amdgpu/sdma_v7_1.c
index f20e0fc3fc74..c3428d2731dc 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v7_1.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v7_1.c
@@ -1764,8 +1764,7 @@ static const struct amdgpu_buffer_funcs 
sdma_v7_1_buffer_funcs = {

  static void sdma_v7_1_set_buffer_funcs(struct amdgpu_device *adev)
  {
-       adev->mman.buffer_funcs = &sdma_v7_1_buffer_funcs;
-       adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].ring;
+       amdgpu_sdma_set_buffer_funcs_scheds(adev, &sdma_v7_1_buffer_funcs);
  }

  const struct amdgpu_ip_block_version sdma_v7_1_ip_block = {
diff --git a/drivers/gpu/drm/amd/amdgpu/si_dma.c 
b/drivers/gpu/drm/amd/amdgpu/si_dma.c
index 3e58feb2d5e4..155067c20a0e 100644
--- a/drivers/gpu/drm/amd/amdgpu/si_dma.c
+++ b/drivers/gpu/drm/amd/amdgpu/si_dma.c
@@ -833,8 +833,7 @@ static const struct amdgpu_buffer_funcs si_dma_buffer_funcs 
= {

  static void si_dma_set_buffer_funcs(struct amdgpu_device *adev)
  {
-       adev->mman.buffer_funcs = &si_dma_buffer_funcs;
-       adev->mman.buffer_funcs_ring = &adev->sdma.instance[0].ring;
+       amdgpu_sdma_set_buffer_funcs_scheds(adev, &si_dma_buffer_funcs);
  }

  const struct amdgpu_ip_block_version si_dma_ip_block =
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c 
b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
index 964efa325908..28dc6886c1ff 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
@@ -129,13 +129,14 @@ svm_migrate_copy_memory_gart(struct amdgpu_device *adev, 
dma_addr_t *sys,
                              struct dma_fence **mfence)
  {
         const u64 GTT_MAX_PAGES = AMDGPU_GTT_MAX_TRANSFER_SIZE;
-       struct amdgpu_ring *ring = adev->mman.buffer_funcs_ring;
+       struct amdgpu_ring *ring;
         struct amdgpu_ttm_buffer_entity *entity;
         u64 gart_s, gart_d;
         struct dma_fence *next;
         u64 size;
         int r;

+       ring = to_amdgpu_ring(adev->mman.buffer_funcs_scheds[0]);
         entity = &adev->mman.move_entities[0];

         mutex_lock(&entity->lock);
--
2.43.0