[PATCH v2] drm/xe/uapi: Uniform async vs sync handling
Thomas Hellström
thomas.hellstrom at linux.intel.com
Wed Dec 13 17:36:58 UTC 2023
On 12/13/23 15:13, Souza, Jose wrote:
> On Tue, 2023-12-12 at 20:35 -0800, Matthew Brost wrote:
>> Remove concept of async vs sync VM bind queues, rather make async vs
>> sync a per IOCTL choice. Since this is per IOCTL, it makes sense to have
>> a singular flag IOCTL rather than per VM bind op flag too. Add
>> DRM_XE_SYNCS_FLAG_WAIT_FOR_OP which is an input sync flag to support
>> this. Support this new flag for both the VM bind IOCTL only with a path
>> to support this for execs too.
>>
>> v2: Add cookie, move sync wait outside of any locks.
>>
>> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
>> Cc: Thomas Hellström <thomas.hellstrom at linux.intel.com>
>> Cc: Francois Dugast <francois.dugast at intel.com>
>> Signed-off-by: Matthew Brost <matthew.brost at intel.com>
>> ---
>> drivers/gpu/drm/xe/xe_exec.c | 12 ++-
>> drivers/gpu/drm/xe/xe_exec_queue.c | 7 +-
>> drivers/gpu/drm/xe/xe_exec_queue_types.h | 2 -
>> drivers/gpu/drm/xe/xe_vm.c | 116 +++++++++++------------
>> drivers/gpu/drm/xe/xe_vm_types.h | 13 ++-
>> include/uapi/drm/xe_drm.h | 64 ++++++++-----
>> 6 files changed, 109 insertions(+), 105 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/xe/xe_exec.c b/drivers/gpu/drm/xe/xe_exec.c
>> index ba92e5619da3..8a1530dab65f 100644
>> --- a/drivers/gpu/drm/xe/xe_exec.c
>> +++ b/drivers/gpu/drm/xe/xe_exec.c
>> @@ -104,7 +104,7 @@ int xe_exec_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>> struct xe_device *xe = to_xe_device(dev);
>> struct xe_file *xef = to_xe_file(file);
>> struct drm_xe_exec *args = data;
>> - struct drm_xe_sync __user *syncs_user = u64_to_user_ptr(args->syncs);
>> + struct drm_xe_sync __user *syncs_user = u64_to_user_ptr(args->syncs.syncs);
>> u64 __user *addresses_user = u64_to_user_ptr(args->address);
>> struct xe_exec_queue *q;
>> struct xe_sync_entry *syncs = NULL;
>> @@ -120,7 +120,9 @@ int xe_exec_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>> int err = 0;
>>
>> if (XE_IOCTL_DBG(xe, args->extensions) ||
>> - XE_IOCTL_DBG(xe, args->pad[0] || args->pad[1] || args->pad[2]) ||
>> + XE_IOCTL_DBG(xe, args->pad || args->pad2[0] || args->pad2[1] || args->pad2[2]) ||
>> + XE_IOCTL_DBG(xe, args->syncs.flags) ||
>> + XE_IOCTL_DBG(xe, args->syncs.cookie) ||
>> XE_IOCTL_DBG(xe, args->reserved[0] || args->reserved[1]))
>> return -EINVAL;
>>
>> @@ -140,8 +142,8 @@ int xe_exec_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>> goto err_exec_queue;
>> }
>>
>> - if (args->num_syncs) {
>> - syncs = kcalloc(args->num_syncs, sizeof(*syncs), GFP_KERNEL);
>> + if (args->syncs.num_syncs) {
>> + syncs = kcalloc(args->syncs.num_syncs, sizeof(*syncs), GFP_KERNEL);
>> if (!syncs) {
>> err = -ENOMEM;
>> goto err_exec_queue;
>> @@ -150,7 +152,7 @@ int xe_exec_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>>
>> vm = q->vm;
>>
>> - for (i = 0; i < args->num_syncs; i++) {
>> + for (i = 0; i < args->syncs.num_syncs; i++) {
>> err = xe_sync_entry_parse(xe, xef, &syncs[num_syncs++],
>> &syncs_user[i], SYNC_PARSE_FLAG_EXEC |
>> (xe_vm_in_lr_mode(vm) ?
>> diff --git a/drivers/gpu/drm/xe/xe_exec_queue.c b/drivers/gpu/drm/xe/xe_exec_queue.c
>> index eeb9605dd45f..a25d67971fdd 100644
>> --- a/drivers/gpu/drm/xe/xe_exec_queue.c
>> +++ b/drivers/gpu/drm/xe/xe_exec_queue.c
>> @@ -625,10 +625,7 @@ int xe_exec_queue_create_ioctl(struct drm_device *dev, void *data,
>> if (XE_IOCTL_DBG(xe, eci[0].gt_id >= xe->info.gt_count))
>> return -EINVAL;
>>
>> - if (eci[0].engine_class >= DRM_XE_ENGINE_CLASS_VM_BIND_ASYNC) {
>> - bool sync = eci[0].engine_class ==
>> - DRM_XE_ENGINE_CLASS_VM_BIND_SYNC;
>> -
>> + if (eci[0].engine_class == DRM_XE_ENGINE_CLASS_VM_BIND) {
>> for_each_gt(gt, xe, id) {
>> struct xe_exec_queue *new;
>>
>> @@ -654,8 +651,6 @@ int xe_exec_queue_create_ioctl(struct drm_device *dev, void *data,
>> args->width, hwe,
>> EXEC_QUEUE_FLAG_PERSISTENT |
>> EXEC_QUEUE_FLAG_VM |
>> - (sync ? 0 :
>> - EXEC_QUEUE_FLAG_VM_ASYNC) |
>> (id ?
>> EXEC_QUEUE_FLAG_BIND_ENGINE_CHILD :
>> 0));
>> diff --git a/drivers/gpu/drm/xe/xe_exec_queue_types.h b/drivers/gpu/drm/xe/xe_exec_queue_types.h
>> index c7aefa1c8c31..0f7f6cded4a3 100644
>> --- a/drivers/gpu/drm/xe/xe_exec_queue_types.h
>> +++ b/drivers/gpu/drm/xe/xe_exec_queue_types.h
>> @@ -84,8 +84,6 @@ struct xe_exec_queue {
>> #define EXEC_QUEUE_FLAG_VM BIT(4)
>> /* child of VM queue for multi-tile VM jobs */
>> #define EXEC_QUEUE_FLAG_BIND_ENGINE_CHILD BIT(5)
>> -/* VM jobs for this queue are asynchronous */
>> -#define EXEC_QUEUE_FLAG_VM_ASYNC BIT(6)
>>
>> /**
>> * @flags: flags for this exec queue, should statically setup aside from ban
>> diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
>> index 2f3df9ee67c9..ab38685d2daf 100644
>> --- a/drivers/gpu/drm/xe/xe_vm.c
>> +++ b/drivers/gpu/drm/xe/xe_vm.c
>> @@ -1343,9 +1343,7 @@ struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags)
>> struct xe_gt *gt = tile->primary_gt;
>> struct xe_vm *migrate_vm;
>> struct xe_exec_queue *q;
>> - u32 create_flags = EXEC_QUEUE_FLAG_VM |
>> - ((flags & XE_VM_FLAG_ASYNC_DEFAULT) ?
>> - EXEC_QUEUE_FLAG_VM_ASYNC : 0);
>> + u32 create_flags = EXEC_QUEUE_FLAG_VM;
>>
>> if (!vm->pt_root[id])
>> continue;
>> @@ -1712,12 +1710,6 @@ xe_vm_bind_vma(struct xe_vma *vma, struct xe_exec_queue *q,
>> return ERR_PTR(err);
>> }
>>
>> -static bool xe_vm_sync_mode(struct xe_vm *vm, struct xe_exec_queue *q)
>> -{
>> - return q ? !(q->flags & EXEC_QUEUE_FLAG_VM_ASYNC) :
>> - !(vm->flags & XE_VM_FLAG_ASYNC_DEFAULT);
>> -}
>> -
>> static int __xe_vm_bind(struct xe_vm *vm, struct xe_vma *vma,
>> struct xe_exec_queue *q, struct xe_sync_entry *syncs,
>> u32 num_syncs, bool immediate, bool first_op,
>> @@ -1747,8 +1739,6 @@ static int __xe_vm_bind(struct xe_vm *vm, struct xe_vma *vma,
>>
>> if (last_op)
>> xe_exec_queue_last_fence_set(wait_exec_queue, vm, fence);
>> - if (last_op && xe_vm_sync_mode(vm, q))
>> - dma_fence_wait(fence, true);
>> dma_fence_put(fence);
>>
>> return 0;
>> @@ -1791,8 +1781,6 @@ static int xe_vm_unbind(struct xe_vm *vm, struct xe_vma *vma,
>> xe_vma_destroy(vma, fence);
>> if (last_op)
>> xe_exec_queue_last_fence_set(wait_exec_queue, vm, fence);
>> - if (last_op && xe_vm_sync_mode(vm, q))
>> - dma_fence_wait(fence, true);
>> dma_fence_put(fence);
>>
>> return 0;
>> @@ -1800,7 +1788,6 @@ static int xe_vm_unbind(struct xe_vm *vm, struct xe_vma *vma,
>>
>> #define ALL_DRM_XE_VM_CREATE_FLAGS (DRM_XE_VM_CREATE_FLAG_SCRATCH_PAGE | \
>> DRM_XE_VM_CREATE_FLAG_LR_MODE | \
>> - DRM_XE_VM_CREATE_FLAG_ASYNC_DEFAULT | \
>> DRM_XE_VM_CREATE_FLAG_FAULT_MODE)
>>
>> int xe_vm_create_ioctl(struct drm_device *dev, void *data,
>> @@ -1854,8 +1841,6 @@ int xe_vm_create_ioctl(struct drm_device *dev, void *data,
>> flags |= XE_VM_FLAG_SCRATCH_PAGE;
>> if (args->flags & DRM_XE_VM_CREATE_FLAG_LR_MODE)
>> flags |= XE_VM_FLAG_LR_MODE;
>> - if (args->flags & DRM_XE_VM_CREATE_FLAG_ASYNC_DEFAULT)
>> - flags |= XE_VM_FLAG_ASYNC_DEFAULT;
>> if (args->flags & DRM_XE_VM_CREATE_FLAG_FAULT_MODE)
>> flags |= XE_VM_FLAG_FAULT_MODE;
>>
>> @@ -2263,8 +2248,7 @@ static int xe_vma_op_commit(struct xe_vm *vm, struct xe_vma_op *op)
>> static int vm_bind_ioctl_ops_parse(struct xe_vm *vm, struct xe_exec_queue *q,
>> struct drm_gpuva_ops *ops,
>> struct xe_sync_entry *syncs, u32 num_syncs,
>> - struct list_head *ops_list, bool last,
>> - bool async)
>> + struct list_head *ops_list, bool last)
>> {
>> struct xe_vma_op *last_op = NULL;
>> struct drm_gpuva_op *__op;
>> @@ -2696,16 +2680,16 @@ static int vm_bind_ioctl_ops_execute(struct xe_vm *vm,
>>
>> #ifdef TEST_VM_ASYNC_OPS_ERROR
>> #define SUPPORTED_FLAGS \
>> - (FORCE_ASYNC_OP_ERROR | DRM_XE_VM_BIND_FLAG_ASYNC | \
>> - DRM_XE_VM_BIND_FLAG_READONLY | DRM_XE_VM_BIND_FLAG_IMMEDIATE | \
>> - DRM_XE_VM_BIND_FLAG_NULL | 0xffff)
>> + (FORCE_ASYNC_OP_ERROR | DRM_XE_VM_BIND_FLAG_READONLY | \
>> + DRM_XE_VM_BIND_FLAG_IMMEDIATE | DRM_XE_VM_BIND_FLAG_NULL | 0xffff)
>> #else
>> #define SUPPORTED_FLAGS \
>> - (DRM_XE_VM_BIND_FLAG_ASYNC | DRM_XE_VM_BIND_FLAG_READONLY | \
>> + (DRM_XE_VM_BIND_FLAG_READONLY | \
>> DRM_XE_VM_BIND_FLAG_IMMEDIATE | DRM_XE_VM_BIND_FLAG_NULL | \
>> 0xffff)
>> #endif
>> #define XE_64K_PAGE_MASK 0xffffull
>> +#define ALL_DRM_XE_SYNCS_FLAGS (DRM_XE_SYNCS_FLAG_WAIT_FOR_OP)
>>
>> #define MAX_BINDS 512 /* FIXME: Picking random upper limit */
>>
>> @@ -2717,7 +2701,7 @@ static int vm_bind_ioctl_check_args(struct xe_device *xe,
>> int err;
>> int i;
>>
>> - if (XE_IOCTL_DBG(xe, args->pad || args->pad2) ||
>> + if (XE_IOCTL_DBG(xe, args->pad) ||
>> XE_IOCTL_DBG(xe, args->reserved[0] || args->reserved[1]))
>> return -EINVAL;
>>
>> @@ -2745,6 +2729,14 @@ static int vm_bind_ioctl_check_args(struct xe_device *xe,
>> *bind_ops = &args->bind;
>> }
>>
>> + *async = !(args->syncs.flags & DRM_XE_SYNCS_FLAG_WAIT_FOR_OP);
>> +
>> + if (XE_IOCTL_DBG(xe, args->syncs.flags & ~ALL_DRM_XE_SYNCS_FLAGS) ||
>> + XE_IOCTL_DBG(xe, !*async && args->syncs.num_syncs)) {
>> + err = -EINVAL;
>> + goto free_bind_ops;
>> + }
>> +
>> for (i = 0; i < args->num_binds; ++i) {
>> u64 range = (*bind_ops)[i].range;
>> u64 addr = (*bind_ops)[i].addr;
>> @@ -2775,18 +2767,6 @@ static int vm_bind_ioctl_check_args(struct xe_device *xe,
>> goto free_bind_ops;
>> }
>>
>> - if (i == 0) {
>> - *async = !!(flags & DRM_XE_VM_BIND_FLAG_ASYNC);
>> - if (XE_IOCTL_DBG(xe, !*async && args->num_syncs)) {
>> - err = -EINVAL;
>> - goto free_bind_ops;
>> - }
>> - } else if (XE_IOCTL_DBG(xe, *async !=
>> - !!(flags & DRM_XE_VM_BIND_FLAG_ASYNC))) {
>> - err = -EINVAL;
>> - goto free_bind_ops;
>> - }
>> -
>> if (XE_IOCTL_DBG(xe, op > DRM_XE_VM_BIND_OP_PREFETCH) ||
>> XE_IOCTL_DBG(xe, flags & ~SUPPORTED_FLAGS) ||
>> XE_IOCTL_DBG(xe, obj && is_null) ||
>> @@ -2854,12 +2834,25 @@ static int vm_bind_ioctl_signal_fences(struct xe_vm *vm,
>>
>> xe_exec_queue_last_fence_set(to_wait_exec_queue(vm, q), vm,
>> fence);
>> + dma_fence_put(fence);
>>
>> - if (xe_vm_sync_mode(vm, q)) {
>> - long timeout = dma_fence_wait(fence, true);
>> + return err;
>> +}
>>
>> - if (timeout < 0)
>> - err = -EINTR;
>> +static int vm_bind_ioctl_sync_wait(struct xe_vm *vm,
>> + struct dma_fence *fence,
>> + u64 __user *cookie)
>> +{
>> + long timeout;
>> + int err = 0;
>> +
>> + timeout = dma_fence_wait(fence, true);
>> + if (timeout < 0) {
>> + u64 value = 1;
>> +
>> + err = -ERESTARTSYS;
>> + if (copy_to_user(cookie, &value, sizeof(value)))
>> + err = -EFAULT;
>> }
>>
>> dma_fence_put(fence);
>> @@ -2875,6 +2868,7 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>> struct drm_xe_sync __user *syncs_user;
>> struct xe_bo **bos = NULL;
>> struct drm_gpuva_ops **ops = NULL;
>> + struct dma_fence *fence = NULL;
>> struct xe_vm *vm;
>> struct xe_exec_queue *q = NULL;
>> u32 num_syncs;
>> @@ -2889,7 +2883,7 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>> if (err)
>> return err;
>>
>> - if (XE_IOCTL_DBG(xe, args->pad || args->pad2) ||
>> + if (XE_IOCTL_DBG(xe, args->pad) ||
>> XE_IOCTL_DBG(xe, args->reserved[0] || args->reserved[1]))
>> return -EINVAL;
>>
>> @@ -2904,12 +2898,6 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>> err = -EINVAL;
>> goto put_exec_queue;
>> }
>> -
>> - if (XE_IOCTL_DBG(xe, args->num_binds && async !=
>> - !!(q->flags & EXEC_QUEUE_FLAG_VM_ASYNC))) {
>> - err = -EINVAL;
>> - goto put_exec_queue;
>> - }
>> }
>>
>> vm = xe_vm_lookup(xef, args->vm_id);
>> @@ -2918,14 +2906,6 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>> goto put_exec_queue;
>> }
>>
>> - if (!args->exec_queue_id) {
>> - if (XE_IOCTL_DBG(xe, args->num_binds && async !=
>> - !!(vm->flags & XE_VM_FLAG_ASYNC_DEFAULT))) {
>> - err = -EINVAL;
>> - goto put_vm;
>> - }
>> - }
>> -
>> err = down_write_killable(&vm->lock);
>> if (err)
>> goto put_vm;
>> @@ -3015,16 +2995,16 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>> }
>> }
>>
>> - if (args->num_syncs) {
>> - syncs = kcalloc(args->num_syncs, sizeof(*syncs), GFP_KERNEL);
>> + if (args->syncs.num_syncs) {
>> + syncs = kcalloc(args->syncs.num_syncs, sizeof(*syncs), GFP_KERNEL);
>> if (!syncs) {
>> err = -ENOMEM;
>> goto put_obj;
>> }
>> }
>>
>> - syncs_user = u64_to_user_ptr(args->syncs);
>> - for (num_syncs = 0; num_syncs < args->num_syncs; num_syncs++) {
>> + syncs_user = u64_to_user_ptr(args->syncs.syncs);
>> + for (num_syncs = 0; num_syncs < args->syncs.num_syncs; num_syncs++) {
>> err = xe_sync_entry_parse(xe, xef, &syncs[num_syncs],
>> &syncs_user[num_syncs],
>> (xe_vm_in_lr_mode(vm) ?
>> @@ -3060,8 +3040,7 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>>
>> err = vm_bind_ioctl_ops_parse(vm, q, ops[i], syncs, num_syncs,
>> &ops_list,
>> - i == args->num_binds - 1,
>> - async);
>> + i == args->num_binds - 1);
>> if (err)
>> goto unwind_ops;
>> }
>> @@ -3077,7 +3056,10 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>> xe_exec_queue_get(q);
>>
>> err = vm_bind_ioctl_ops_execute(vm, &ops_list);
>> -
>> + if (!err && !async) {
>> + fence = xe_exec_queue_last_fence_get(to_wait_exec_queue(vm, q), vm);
>> + dma_fence_get(fence);
>> + }
>> up_write(&vm->lock);
>>
>> if (q)
>> @@ -3092,13 +3074,19 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>> if (args->num_binds > 1)
>> kfree(bind_ops);
>>
>> - return err;
>> + return fence ? vm_bind_ioctl_sync_wait(vm, fence, u64_to_user_ptr(args->syncs.cookie)) :
>> + err;
>>
>> unwind_ops:
>> vm_bind_ioctl_ops_unwind(vm, ops, args->num_binds);
>> free_syncs:
>> - if (err == -ENODATA)
>> + if (err == -ENODATA) {
>> err = vm_bind_ioctl_signal_fences(vm, q, syncs, num_syncs);
>> + if (!async) {
>> + fence = xe_exec_queue_last_fence_get(to_wait_exec_queue(vm, q), vm);
>> + dma_fence_get(fence);
>> + }
>> + }
>> while (num_syncs--)
>> xe_sync_entry_cleanup(&syncs[num_syncs]);
>>
>> @@ -3108,6 +3096,8 @@ int xe_vm_bind_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
>> xe_bo_put(bos[i]);
>> release_vm_lock:
>> up_write(&vm->lock);
>> + if (fence)
>> + err = vm_bind_ioctl_sync_wait(vm, fence, u64_to_user_ptr(args->syncs.cookie));
>> put_vm:
>> xe_vm_put(vm);
>> put_exec_queue:
>> diff --git a/drivers/gpu/drm/xe/xe_vm_types.h b/drivers/gpu/drm/xe/xe_vm_types.h
>> index 2e023596cb15..63e8a50b88e9 100644
>> --- a/drivers/gpu/drm/xe/xe_vm_types.h
>> +++ b/drivers/gpu/drm/xe/xe_vm_types.h
>> @@ -138,13 +138,12 @@ struct xe_vm {
>> */
>> #define XE_VM_FLAG_64K BIT(0)
>> #define XE_VM_FLAG_LR_MODE BIT(1)
>> -#define XE_VM_FLAG_ASYNC_DEFAULT BIT(2)
>> -#define XE_VM_FLAG_MIGRATION BIT(3)
>> -#define XE_VM_FLAG_SCRATCH_PAGE BIT(4)
>> -#define XE_VM_FLAG_FAULT_MODE BIT(5)
>> -#define XE_VM_FLAG_BANNED BIT(6)
>> -#define XE_VM_FLAG_TILE_ID(flags) FIELD_GET(GENMASK(8, 7), flags)
>> -#define XE_VM_FLAG_SET_TILE_ID(tile) FIELD_PREP(GENMASK(8, 7), (tile)->id)
>> +#define XE_VM_FLAG_MIGRATION BIT(2)
>> +#define XE_VM_FLAG_SCRATCH_PAGE BIT(3)
>> +#define XE_VM_FLAG_FAULT_MODE BIT(4)
>> +#define XE_VM_FLAG_BANNED BIT(5)
>> +#define XE_VM_FLAG_TILE_ID(flags) FIELD_GET(GENMASK(7, 6), flags)
>> +#define XE_VM_FLAG_SET_TILE_ID(tile) FIELD_PREP(GENMASK(7, 6), (tile)->id)
>> unsigned long flags;
>>
>> /** @composite_fence_ctx: context composite fence */
>> diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
>> index 0895e4d2a981..d72e4441cc80 100644
>> --- a/include/uapi/drm/xe_drm.h
>> +++ b/include/uapi/drm/xe_drm.h
>> @@ -140,8 +140,7 @@ struct drm_xe_engine_class_instance {
>> * Kernel only classes (not actual hardware engine class). Used for
>> * creating ordered queues of VM bind operations.
>> */
>> -#define DRM_XE_ENGINE_CLASS_VM_BIND_ASYNC 5
>> -#define DRM_XE_ENGINE_CLASS_VM_BIND_SYNC 6
>> +#define DRM_XE_ENGINE_CLASS_VM_BIND 5
>> /** @engine_class: engine class id */
>> __u16 engine_class;
>> /** @engine_instance: engine instance id */
>> @@ -661,7 +660,6 @@ struct drm_xe_vm_create {
>> * still enable recoverable pagefaults if supported by the device.
>> */
>> #define DRM_XE_VM_CREATE_FLAG_LR_MODE (1 << 1)
>> -#define DRM_XE_VM_CREATE_FLAG_ASYNC_DEFAULT (1 << 2)
>> /*
>> * DRM_XE_VM_CREATE_FLAG_FAULT_MODE requires also
>> * DRM_XE_VM_CREATE_FLAG_LR_MODE. It allows memory to be allocated
>> @@ -669,7 +667,7 @@ struct drm_xe_vm_create {
>> * The xe driver internally uses recoverable pagefaults to implement
>> * this.
>> */
>> -#define DRM_XE_VM_CREATE_FLAG_FAULT_MODE (1 << 3)
>> +#define DRM_XE_VM_CREATE_FLAG_FAULT_MODE (1 << 2)
>> /** @flags: Flags */
>> __u32 flags;
>>
>> @@ -777,12 +775,11 @@ struct drm_xe_vm_bind_op {
>> __u32 op;
>>
>> #define DRM_XE_VM_BIND_FLAG_READONLY (1 << 0)
>> -#define DRM_XE_VM_BIND_FLAG_ASYNC (1 << 1)
>> /*
>> * Valid on a faulting VM only, do the MAP operation immediately rather
>> * than deferring the MAP to the page fault handler.
>> */
>> -#define DRM_XE_VM_BIND_FLAG_IMMEDIATE (1 << 2)
>> +#define DRM_XE_VM_BIND_FLAG_IMMEDIATE (1 << 1)
>> /*
>> * When the NULL flag is set, the page tables are setup with a special
>> * bit which indicates writes are dropped and all reads return zero. In
>> @@ -790,7 +787,7 @@ struct drm_xe_vm_bind_op {
>> * operations, the BO handle MBZ, and the BO offset MBZ. This flag is
>> * intended to implement VK sparse bindings.
>> */
>> -#define DRM_XE_VM_BIND_FLAG_NULL (1 << 3)
>> +#define DRM_XE_VM_BIND_FLAG_NULL (1 << 2)
>> /** @flags: Bind flags */
>> __u32 flags;
>>
>> @@ -808,6 +805,35 @@ struct drm_xe_vm_bind_op {
>> __u64 reserved[3];
>> };
>>
>> +/**
>> + * struct drm_xe_syncs - In / out syncs for IOCTLs.
>> + */
>> +struct drm_xe_syncs {
>> + /** @num_syncs: amount of syncs to wait on */
>> + __u32 num_syncs;
>> +
>> + /*
>> + * Block in IOCTL until operation complete, num_syncs MBZ if set.
>> + */
>> +#define DRM_XE_SYNCS_FLAG_WAIT_FOR_OP (1 << 0)
>> + /** @flags: Sync flags */
>> + __u32 flags;
>> +
>> + /**
>> + * @cookie: pointer which is written with an non-zero value if IOCTL
>> + * operation has been committed but the wait for completion
>> + * (DRM_XE_SYNCS_FLAG_WAIT_FOR_OP is set) is interrupted. Value only
>> + * valid when IOCTL returns -EINTR or -ERESTARTSYS.
>> + */
>> + __u64 cookie;
> what is the usage of cookie?
> from what I looked the xe_vm_bind_ioctl() will return -1 and errno will be set to -ERESTARTSYS in the case mentioned in the comment.
>
> if really needed would be nice if you could provide a example of how it should be used.
It's opaque to user-space, except for clearing before first command
submission.
If the wait for operation complete hits a signal, then the IOCTL writes
a 1 to "cooke" and is then restarted either by the kernel itself or by
user-space (Unless it was a CTRL-C) The KMD then reads the value of
cookie. If it sees that it is 1, it skips performing the bind again, and
goes directly to the wait part...
This is not very nice IMO, but is the price we pay for interruptible
waits after the BIND has been commited. IMO it's better that user-space,
at least in production code, implements sync binds using async binds
with a follow-up wait for an out-(user) fence.
>
>> +
>> + /** @syncs: pointer to struct drm_xe_sync array */
>> + __u64 syncs;
>> +
>> + /** @reserved: Reserved */
>> + __u64 reserved[2];
>> +};
>> +
>> struct drm_xe_vm_bind {
>> /** @extensions: Pointer to the first extension struct, if any */
>> __u64 extensions;
>> @@ -839,14 +865,8 @@ struct drm_xe_vm_bind {
>> __u64 vector_of_binds;
>> };
>>
>> - /** @pad: MBZ */
>> - __u32 pad2;
>> -
>> - /** @num_syncs: amount of syncs to wait on */
>> - __u32 num_syncs;
>> -
>> - /** @syncs: pointer to struct drm_xe_sync array */
>> - __u64 syncs;
>> + /** @syncs: syncs for bind */
>> + struct drm_xe_syncs syncs;
>>
>> /** @reserved: Reserved */
>> __u64 reserved[2];
>> @@ -975,14 +995,14 @@ struct drm_xe_exec {
>> /** @extensions: Pointer to the first extension struct, if any */
>> __u64 extensions;
>>
>> + /** @pad: MBZ */
>> + __u32 pad;
>> +
>> /** @exec_queue_id: Exec queue ID for the batch buffer */
>> __u32 exec_queue_id;
>>
>> - /** @num_syncs: Amount of struct drm_xe_sync in array. */
>> - __u32 num_syncs;
>> -
>> - /** @syncs: Pointer to struct drm_xe_sync array. */
>> - __u64 syncs;
>> + /** @syncs: syncs for exec */
>> + struct drm_xe_syncs syncs;
> DRM_XE_SYNCS_FLAG_WAIT_FOR_OP is not implemented for DRM_IOCTL_XE_EXEC.
That is intentional. The scheme above is awkward and IMO we shouldn't
implement it for EXEC unless there is a specific need, that cannot be
solved with waiting for an out-fence.
/Thomas
>
>>
>> /**
>> * @address: address of batch buffer if num_batch_buffer == 1 or an
>> @@ -996,8 +1016,8 @@ struct drm_xe_exec {
>> */
>> __u16 num_batch_buffer;
>>
>> - /** @pad: MBZ */
>> - __u16 pad[3];
>> + /** @pad2: MBZ */
>> + __u16 pad2[3];
>>
>> /** @reserved: Reserved */
>> __u64 reserved[2];
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