[RFC PATCH] drm/amdgpu: add support for user trap handlers
Alex Deucher
alexdeucher at gmail.com
Mon Aug 24 21:32:36 UTC 2020
On Mon, Aug 24, 2020 at 2:33 PM Alex Deucher <alexdeucher at gmail.com> wrote:
>
> On Mon, Aug 24, 2020 at 7:57 AM Samuel Pitoiset
> <samuel.pitoiset at gmail.com> wrote:
> >
> > A trap handler can be used by userspace to catch shader exceptions
> > like divide by zero, memory violations etc.
> >
> > On GFX6-GFX8, the registers used to configure TBA/TMA aren't
> > privileged while on GFX9+ they are per VMID and privileged,
> > so that only the KMD can configure them.
> >
> > This introduces a new CS chunk that can be used to set the
> > TBA/TMA virtual address at submit time.
> >
> > TODO:
> > - add GFX 6,7 and 10 support
> > - rebase on top of amd-staging-drm-next (this branch currently
> > hangs my GPU at boot)
> >
> > Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
> > ---
> > drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 31 +++++++++++++++++
> > drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 3 +-
> > drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h | 4 +++
> > drivers/gpu/drm/amd/amdgpu/amdgpu_job.h | 4 +++
> > drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h | 4 +++
> > drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 15 ++++++++-
> > drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c | 42 ++++++++++++++++++++++--
> > drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c | 19 +++++++++++
> > include/uapi/drm/amdgpu_drm.h | 8 +++++
> > 9 files changed, 126 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> > index a512ccbc4dea..6ca5c4912e3a 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
> > @@ -104,6 +104,19 @@ static int amdgpu_cs_bo_handles_chunk(struct amdgpu_cs_parser *p,
> > return r;
> > }
> >
> > +static int amdgpu_cs_user_trap_chunk(struct amdgpu_cs_parser *p,
> > + struct drm_amdgpu_cs_chunk_trap *data,
> > + uint64_t *tba_addr, uint64_t *tma_addr)
> > +{
> > + if (!data->tba_addr || !data->tma_addr)
> > + return -EINVAL;
> > +
> > + *tba_addr = data->tba_addr;
> > + *tma_addr = data->tma_addr;
> > +
> > + return 0;
> > +}
> > +
> > static int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, union drm_amdgpu_cs *cs)
> > {
> > struct amdgpu_fpriv *fpriv = p->filp->driver_priv;
> > @@ -112,6 +125,7 @@ static int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, union drm_amdgpu_cs
> > uint64_t *chunk_array;
> > unsigned size, num_ibs = 0;
> > uint32_t uf_offset = 0;
> > + uint64_t tba_addr = 0, tma_addr = 0;
> > int i;
> > int ret;
> >
> > @@ -214,6 +228,19 @@ static int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, union drm_amdgpu_cs
> >
> > break;
> >
> > + case AMDGPU_CHUNK_ID_TRAP:
> > + size = sizeof(struct drm_amdgpu_cs_chunk_trap);
> > + if (p->chunks[i].length_dw * sizeof(uint32_t) < size) {
> > + ret = -EINVAL;
> > + goto free_partial_kdata;
> > + }
> > +
> > + ret = amdgpu_cs_user_trap_chunk(p, p->chunks[i].kdata,
> > + &tba_addr, &tma_addr);
> > + if (ret)
> > + goto free_partial_kdata;
> > + break;
> > +
> > case AMDGPU_CHUNK_ID_DEPENDENCIES:
> > case AMDGPU_CHUNK_ID_SYNCOBJ_IN:
> > case AMDGPU_CHUNK_ID_SYNCOBJ_OUT:
> > @@ -239,6 +266,10 @@ static int amdgpu_cs_parser_init(struct amdgpu_cs_parser *p, union drm_amdgpu_cs
> >
> > if (p->uf_entry.tv.bo)
> > p->job->uf_addr = uf_offset;
> > +
> > + p->job->tba_addr = tba_addr;
> > + p->job->tma_addr = tma_addr;
> > +
> > kfree(chunk_array);
> >
> > /* Use this opportunity to fill in task info for the vm */
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > index 26127c7d2f32..1e703119e4c2 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> > @@ -88,9 +88,10 @@
> > * - 3.37.0 - L2 is invalidated before SDMA IBs, needed for correctness
> > * - 3.38.0 - Add AMDGPU_IB_FLAG_EMIT_MEM_SYNC
> > * - 3.39.0 - DMABUF implicit sync does a full pipeline sync
> > + * - 3.40.0 - Add AMDGPU_CHUNK_ID_TRAP
> > */
> > #define KMS_DRIVER_MAJOR 3
> > -#define KMS_DRIVER_MINOR 39
> > +#define KMS_DRIVER_MINOR 40
> > #define KMS_DRIVER_PATCHLEVEL 0
> >
> > int amdgpu_vram_limit = 0;
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h
> > index 8e58325bbca2..fd0d56724b4d 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ids.h
> > @@ -58,6 +58,10 @@ struct amdgpu_vmid {
> > uint32_t oa_base;
> > uint32_t oa_size;
> >
> > + /* user trap */
> > + uint64_t tba_addr;
> > + uint64_t tma_addr;
> > +
> > unsigned pasid;
> > struct dma_fence *pasid_mapping;
> > };
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.h
> > index 81caac9b958a..b8ed5b13ea44 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_job.h
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_job.h
> > @@ -62,6 +62,10 @@ struct amdgpu_job {
> > /* user fence handling */
> > uint64_t uf_addr;
> > uint64_t uf_sequence;
> > +
> > + /* user trap handling */
> > + uint64_t tba_addr;
> > + uint64_t tma_addr;
> > };
> >
> > int amdgpu_job_alloc(struct amdgpu_device *adev, unsigned num_ibs,
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
> > index da871d84b742..1f165a6295d9 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
> > @@ -197,6 +197,9 @@ struct amdgpu_ring_funcs {
> > void (*soft_recovery)(struct amdgpu_ring *ring, unsigned vmid);
> > int (*preempt_ib)(struct amdgpu_ring *ring);
> > void (*emit_mem_sync)(struct amdgpu_ring *ring);
> > + void (*emit_trap_handler)(struct amdgpu_ring *ring,
> > + uint32_t vmid,
> > + uint64_t tba_addr, uint64_t tma_addr);
> > };
> >
> > struct amdgpu_ring {
> > @@ -265,6 +268,7 @@ struct amdgpu_ring {
> > #define amdgpu_ring_emit_vm_flush(r, vmid, addr) (r)->funcs->emit_vm_flush((r), (vmid), (addr))
> > #define amdgpu_ring_emit_fence(r, addr, seq, flags) (r)->funcs->emit_fence((r), (addr), (seq), (flags))
> > #define amdgpu_ring_emit_gds_switch(r, v, db, ds, wb, ws, ab, as) (r)->funcs->emit_gds_switch((r), (v), (db), (ds), (wb), (ws), (ab), (as))
> > +#define amdgpu_ring_emit_trap_handler(r, v, tba, tma) (r)->funcs->emit_trap_handler((r), (v), (tba), (tma))
> > #define amdgpu_ring_emit_hdp_flush(r) (r)->funcs->emit_hdp_flush((r))
> > #define amdgpu_ring_emit_switch_buffer(r) (r)->funcs->emit_switch_buffer((r))
> > #define amdgpu_ring_emit_cntxcntl(r, d) (r)->funcs->emit_cntxcntl((r), (d))
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> > index 71e005cf2952..24916082de0b 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> > @@ -1076,6 +1076,9 @@ int amdgpu_vm_flush(struct amdgpu_ring *ring, struct amdgpu_job *job,
> > id->gws_size != job->gws_size ||
> > id->oa_base != job->oa_base ||
> > id->oa_size != job->oa_size);
> > + bool trap_handler_needed = ring->funcs->emit_trap_handler && (
> > + id->tba_addr != job->tba_addr ||
> > + id->tma_addr != job->tma_addr);
> > bool vm_flush_needed = job->vm_needs_flush;
> > struct dma_fence *fence = NULL;
> > bool pasid_mapping_needed = false;
> > @@ -1088,6 +1091,7 @@ int amdgpu_vm_flush(struct amdgpu_ring *ring, struct amdgpu_job *job,
> >
> > if (amdgpu_vmid_had_gpu_reset(adev, id)) {
> > gds_switch_needed = true;
> > + trap_handler_needed = true;
> > vm_flush_needed = true;
> > pasid_mapping_needed = true;
> > }
> > @@ -1099,12 +1103,14 @@ int amdgpu_vm_flush(struct amdgpu_ring *ring, struct amdgpu_job *job,
> > mutex_unlock(&id_mgr->lock);
> >
> > gds_switch_needed &= !!ring->funcs->emit_gds_switch;
> > + trap_handler_needed &= !!ring->funcs->emit_trap_handler;
> > vm_flush_needed &= !!ring->funcs->emit_vm_flush &&
> > job->vm_pd_addr != AMDGPU_BO_INVALID_OFFSET;
> > pasid_mapping_needed &= adev->gmc.gmc_funcs->emit_pasid_mapping &&
> > ring->funcs->emit_wreg;
> >
> > - if (!vm_flush_needed && !gds_switch_needed && !need_pipe_sync)
> > + if (!vm_flush_needed && !gds_switch_needed &&
> > + !trap_handler_needed && !need_pipe_sync)
> > return 0;
> >
> > if (ring->funcs->init_cond_exec)
> > @@ -1158,6 +1164,13 @@ int amdgpu_vm_flush(struct amdgpu_ring *ring, struct amdgpu_job *job,
> > job->oa_size);
> > }
> >
> > + if (ring->funcs->emit_trap_handler && trap_handler_needed) {
> > + id->tba_addr = job->tba_addr;
> > + id->tma_addr = job->tma_addr;
> > + amdgpu_ring_emit_trap_handler(ring, job->vmid, job->tba_addr,
> > + job->tma_addr);
> > + }
> > +
> > if (ring->funcs->patch_cond_exec)
> > amdgpu_ring_patch_cond_exec(ring, patch_offset);
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
> > index 33f1c4a46ebe..59db577e8c8f 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c
> > @@ -5222,6 +5222,40 @@ static void gfx_v8_0_ring_emit_gds_switch(struct amdgpu_ring *ring,
> > amdgpu_ring_write(ring, (1 << (oa_size + oa_base)) - (1 << oa_base));
> > }
> >
> > +static void gfx_v8_0_ring_emit_trap_handler(struct amdgpu_ring *ring,
> > + uint32_t vmid,
> > + uint64_t tba_addr,
> > + uint64_t tma_addr)
> > +{
> > + if (ring->funcs->type == AMDGPU_RING_TYPE_GFX) {
> > + static const u32 regs[] = {
> > + mmSPI_SHADER_TBA_LO_PS,
> > + mmSPI_SHADER_TBA_LO_VS,
> > + mmSPI_SHADER_TBA_LO_GS,
> > + mmSPI_SHADER_TBA_LO_ES,
> > + mmSPI_SHADER_TBA_LO_HS,
> > + mmSPI_SHADER_TBA_LO_LS,
> > + };
> > + int i;
> > +
> > + for (i = 0; i < ARRAY_SIZE(regs); i++) {
> > + amdgpu_ring_write(ring, PACKET3(PACKET3_SET_SH_REG, 4));
> > + amdgpu_ring_write(ring, regs[i] - PACKET3_SET_SH_REG_START);
> > + amdgpu_ring_write(ring, lower_32_bits(tba_addr >> 8));
> > + amdgpu_ring_write(ring, upper_32_bits(tba_addr >> 8));
> > + amdgpu_ring_write(ring, lower_32_bits(tma_addr >> 8));
> > + amdgpu_ring_write(ring, upper_32_bits(tma_addr >> 8));
> > + }
> > + } else {
> > + amdgpu_ring_write(ring, PACKET3(PACKET3_SET_SH_REG, 4));
> > + amdgpu_ring_write(ring, mmCOMPUTE_TBA_LO - PACKET3_SET_SH_REG_START);
> > + amdgpu_ring_write(ring, lower_32_bits(tba_addr >> 8));
> > + amdgpu_ring_write(ring, upper_32_bits(tba_addr >> 8));
> > + amdgpu_ring_write(ring, lower_32_bits(tma_addr >> 8));
> > + amdgpu_ring_write(ring, upper_32_bits(tma_addr >> 8));
> > + }
> > +}
> > +
> > static uint32_t wave_read_ind(struct amdgpu_device *adev, uint32_t simd, uint32_t wave, uint32_t address)
> > {
> > WREG32(mmSQ_IND_INDEX,
> > @@ -6890,7 +6924,8 @@ static const struct amdgpu_ring_funcs gfx_v8_0_ring_funcs_gfx = {
> > 5 + /* HDP_INVL */
> > 12 + 12 + /* FENCE x2 */
> > 2 + /* SWITCH_BUFFER */
> > - 5, /* SURFACE_SYNC */
> > + 5 + /* SURFACE_SYNC */
> > + 36, /* gfx_v8_0_ring_emit_trap_handler */
> > .emit_ib_size = 4, /* gfx_v8_0_ring_emit_ib_gfx */
> > .emit_ib = gfx_v8_0_ring_emit_ib_gfx,
> > .emit_fence = gfx_v8_0_ring_emit_fence_gfx,
> > @@ -6909,6 +6944,7 @@ static const struct amdgpu_ring_funcs gfx_v8_0_ring_funcs_gfx = {
> > .emit_wreg = gfx_v8_0_ring_emit_wreg,
> > .soft_recovery = gfx_v8_0_ring_soft_recovery,
> > .emit_mem_sync = gfx_v8_0_emit_mem_sync,
> > + .emit_trap_handler = gfx_v8_0_ring_emit_trap_handler,
> > };
> >
> > static const struct amdgpu_ring_funcs gfx_v8_0_ring_funcs_compute = {
> > @@ -6926,7 +6962,8 @@ static const struct amdgpu_ring_funcs gfx_v8_0_ring_funcs_compute = {
> > 7 + /* gfx_v8_0_ring_emit_pipeline_sync */
> > VI_FLUSH_GPU_TLB_NUM_WREG * 5 + 7 + /* gfx_v8_0_ring_emit_vm_flush */
> > 7 + 7 + 7 + /* gfx_v8_0_ring_emit_fence_compute x3 for user fence, vm fence */
> > - 7, /* gfx_v8_0_emit_mem_sync_compute */
> > + 7 + /* gfx_v8_0_emit_mem_sync_compute */
> > + 6, /* gfx_v8_0_emit_trap_handler */
> > .emit_ib_size = 7, /* gfx_v8_0_ring_emit_ib_compute */
> > .emit_ib = gfx_v8_0_ring_emit_ib_compute,
> > .emit_fence = gfx_v8_0_ring_emit_fence_compute,
> > @@ -6940,6 +6977,7 @@ static const struct amdgpu_ring_funcs gfx_v8_0_ring_funcs_compute = {
> > .pad_ib = amdgpu_ring_generic_pad_ib,
> > .emit_wreg = gfx_v8_0_ring_emit_wreg,
> > .emit_mem_sync = gfx_v8_0_emit_mem_sync_compute,
> > + .emit_trap_handler = gfx_v8_0_ring_emit_trap_handler,
> > };
> >
> > static const struct amdgpu_ring_funcs gfx_v8_0_ring_funcs_kiq = {
> > diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c
> > index cb9d60a4e05e..4fc00f196085 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c
> > @@ -4162,6 +4162,23 @@ static void gfx_v9_0_ring_emit_gds_switch(struct amdgpu_ring *ring,
> > (1 << (oa_size + oa_base)) - (1 << oa_base));
> > }
> >
> > +static void gfx_v9_0_ring_emit_trap_handler(struct amdgpu_ring *ring,
> > + uint32_t vmid,
> > + uint64_t tba_addr,
> > + uint64_t tma_addr)
> > +{
> > + struct amdgpu_device *adev = ring->adev;
> > +
> > + mutex_lock(&adev->srbm_mutex);
> > + soc15_grbm_select(adev, 0, 0, 0, vmid);
> > + WREG32_SOC15_RLC(GC, 0, mmSQ_SHADER_TBA_LO, lower_32_bits(tba_addr >> 8));
> > + WREG32_SOC15_RLC(GC, 0, mmSQ_SHADER_TBA_HI, upper_32_bits(tba_addr >> 8));
> > + WREG32_SOC15_RLC(GC, 0, mmSQ_SHADER_TMA_LO, lower_32_bits(tma_addr >> 8));
> > + WREG32_SOC15_RLC(GC, 0, mmSQ_SHADER_TMA_HI, upper_32_bits(tma_addr >> 8));
> > + soc15_grbm_select(adev, 0, 0, 0, 0);
> > + mutex_unlock(&adev->srbm_mutex);
>
> This won't work. This updates registers via MMIO using the CPU. We
> need to have the registers updated asynchronously via the CP so they
> get updated when the specific jobs are executed by the engine. vmid's
> are shared resources and are assigned dynamically via the kernel
> driver. If you update via MMIO the changes take effect immediately
> rather than when the actual work is scheduled on the engine.
> Unfortunately, at the moment, I don't see a way to do this with the CP
> with the packets that are currently available.
One option might be to do this via MMIO, but only support it when
using a reserved vmid.
Alex
>
> Alex
>
>
> > +}
> > +
> > static const u32 vgpr_init_compute_shader[] =
> > {
> > 0xb07c0000, 0xbe8000ff,
> > @@ -6720,6 +6737,7 @@ static const struct amdgpu_ring_funcs gfx_v9_0_ring_funcs_gfx = {
> > .emit_reg_write_reg_wait = gfx_v9_0_ring_emit_reg_write_reg_wait,
> > .soft_recovery = gfx_v9_0_ring_soft_recovery,
> > .emit_mem_sync = gfx_v9_0_emit_mem_sync,
> > + .emit_trap_handler = gfx_v9_0_ring_emit_trap_handler,
> > };
> >
> > static const struct amdgpu_ring_funcs gfx_v9_0_ring_funcs_compute = {
> > @@ -6756,6 +6774,7 @@ static const struct amdgpu_ring_funcs gfx_v9_0_ring_funcs_compute = {
> > .emit_reg_wait = gfx_v9_0_ring_emit_reg_wait,
> > .emit_reg_write_reg_wait = gfx_v9_0_ring_emit_reg_write_reg_wait,
> > .emit_mem_sync = gfx_v9_0_emit_mem_sync,
> > + .emit_trap_handler = gfx_v9_0_ring_emit_trap_handler,
> > };
> >
> > static const struct amdgpu_ring_funcs gfx_v9_0_ring_funcs_kiq = {
> > diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h
> > index 3218576e109d..7eae264adb5d 100644
> > --- a/include/uapi/drm/amdgpu_drm.h
> > +++ b/include/uapi/drm/amdgpu_drm.h
> > @@ -551,6 +551,7 @@ struct drm_amdgpu_gem_va {
> > #define AMDGPU_CHUNK_ID_SCHEDULED_DEPENDENCIES 0x07
> > #define AMDGPU_CHUNK_ID_SYNCOBJ_TIMELINE_WAIT 0x08
> > #define AMDGPU_CHUNK_ID_SYNCOBJ_TIMELINE_SIGNAL 0x09
> > +#define AMDGPU_CHUNK_ID_TRAP 0x0a
> >
> > struct drm_amdgpu_cs_chunk {
> > __u32 chunk_id;
> > @@ -645,6 +646,13 @@ struct drm_amdgpu_cs_chunk_syncobj {
> > __u64 point;
> > };
> >
> > +struct drm_amdgpu_cs_chunk_trap {
> > + /** Trap Base Address */
> > + __u64 tba_addr;
> > + /** Trap Memory Address */
> > + __u64 tma_addr;
> > +};
> > +
> > #define AMDGPU_FENCE_TO_HANDLE_GET_SYNCOBJ 0
> > #define AMDGPU_FENCE_TO_HANDLE_GET_SYNCOBJ_FD 1
> > #define AMDGPU_FENCE_TO_HANDLE_GET_SYNC_FILE_FD 2
> > --
> > 2.28.0
> >
> > _______________________________________________
> > amd-gfx mailing list
> > amd-gfx at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/amd-gfx
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