mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
![Thomas Hellström](/assets/img/avatar_default.png)
Since it's starting to be used outside the i915 TTM move code, move it to a separate set of files. v2: - Update the documentation. v4: - Rebase. Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20211221200050.436316-4-thomas.hellstrom@linux.intel.com
237 lines
6.5 KiB
C
237 lines
6.5 KiB
C
// SPDX-License-Identifier: MIT
|
|
/*
|
|
* Copyright © 2021 Intel Corporation
|
|
*/
|
|
|
|
#include <linux/dma-fence.h>
|
|
#include <linux/slab.h>
|
|
|
|
#include <drm/ttm/ttm_bo_api.h>
|
|
|
|
#include "i915_deps.h"
|
|
|
|
/**
|
|
* DOC: Set of utilities to dynamically collect dependencies into a
|
|
* structure which is fed into the GT migration code.
|
|
*
|
|
* Once we can do async unbinding, this is also needed to coalesce
|
|
* the migration fence with the unbind fences if these are coalesced
|
|
* post-migration.
|
|
*
|
|
* While collecting the individual dependencies, we store the refcounted
|
|
* struct dma_fence pointers in a realloc-managed pointer array, since
|
|
* that can be easily fed into a dma_fence_array. Other options are
|
|
* available, like for example an xarray for similarity with drm/sched.
|
|
* Can be changed easily if needed.
|
|
*
|
|
* A struct i915_deps need to be initialized using i915_deps_init().
|
|
* If i915_deps_add_dependency() or i915_deps_add_resv() return an
|
|
* error code they will internally call i915_deps_fini(), which frees
|
|
* all internal references and allocations.
|
|
*/
|
|
|
|
/* Min number of fence pointers in the array when an allocation occurs. */
|
|
#define I915_DEPS_MIN_ALLOC_CHUNK 8U
|
|
|
|
static void i915_deps_reset_fences(struct i915_deps *deps)
|
|
{
|
|
if (deps->fences != &deps->single)
|
|
kfree(deps->fences);
|
|
deps->num_deps = 0;
|
|
deps->fences_size = 1;
|
|
deps->fences = &deps->single;
|
|
}
|
|
|
|
/**
|
|
* i915_deps_init - Initialize an i915_deps structure
|
|
* @deps: Pointer to the i915_deps structure to initialize.
|
|
* @gfp: The allocation mode for subsequenst allocations.
|
|
*/
|
|
void i915_deps_init(struct i915_deps *deps, gfp_t gfp)
|
|
{
|
|
deps->fences = NULL;
|
|
deps->gfp = gfp;
|
|
i915_deps_reset_fences(deps);
|
|
}
|
|
|
|
/**
|
|
* i915_deps_fini - Finalize an i915_deps structure
|
|
* @deps: Pointer to the i915_deps structure to finalize.
|
|
*
|
|
* This function drops all fence references taken, conditionally frees and
|
|
* then resets the fences array.
|
|
*/
|
|
void i915_deps_fini(struct i915_deps *deps)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < deps->num_deps; ++i)
|
|
dma_fence_put(deps->fences[i]);
|
|
|
|
if (deps->fences != &deps->single)
|
|
kfree(deps->fences);
|
|
}
|
|
|
|
static int i915_deps_grow(struct i915_deps *deps, struct dma_fence *fence,
|
|
const struct ttm_operation_ctx *ctx)
|
|
{
|
|
int ret;
|
|
|
|
if (deps->num_deps >= deps->fences_size) {
|
|
unsigned int new_size = 2 * deps->fences_size;
|
|
struct dma_fence **new_fences;
|
|
|
|
new_size = max(new_size, I915_DEPS_MIN_ALLOC_CHUNK);
|
|
new_fences = kmalloc_array(new_size, sizeof(*new_fences), deps->gfp);
|
|
if (!new_fences)
|
|
goto sync;
|
|
|
|
memcpy(new_fences, deps->fences,
|
|
deps->fences_size * sizeof(*new_fences));
|
|
swap(new_fences, deps->fences);
|
|
if (new_fences != &deps->single)
|
|
kfree(new_fences);
|
|
deps->fences_size = new_size;
|
|
}
|
|
deps->fences[deps->num_deps++] = dma_fence_get(fence);
|
|
return 0;
|
|
|
|
sync:
|
|
if (ctx->no_wait_gpu && !dma_fence_is_signaled(fence)) {
|
|
ret = -EBUSY;
|
|
goto unref;
|
|
}
|
|
|
|
ret = dma_fence_wait(fence, ctx->interruptible);
|
|
if (ret)
|
|
goto unref;
|
|
|
|
ret = fence->error;
|
|
if (ret)
|
|
goto unref;
|
|
|
|
return 0;
|
|
|
|
unref:
|
|
i915_deps_fini(deps);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* i915_deps_sync - Wait for all the fences in the dependency collection
|
|
* @deps: Pointer to the i915_deps structure the fences of which to wait for.
|
|
* @ctx: Pointer to a struct ttm_operation_ctx indicating how the waits
|
|
* should be performed.
|
|
*
|
|
* This function waits for fences in the dependency collection. If it
|
|
* encounters an error during the wait or a fence error, the wait for
|
|
* further fences is aborted and the error returned.
|
|
*
|
|
* Return: Zero if successful, Negative error code on error.
|
|
*/
|
|
int i915_deps_sync(const struct i915_deps *deps, const struct ttm_operation_ctx *ctx)
|
|
{
|
|
struct dma_fence **fences = deps->fences;
|
|
unsigned int i;
|
|
int ret = 0;
|
|
|
|
for (i = 0; i < deps->num_deps; ++i, ++fences) {
|
|
if (ctx->no_wait_gpu && !dma_fence_is_signaled(*fences)) {
|
|
ret = -EBUSY;
|
|
break;
|
|
}
|
|
|
|
ret = dma_fence_wait(*fences, ctx->interruptible);
|
|
if (!ret)
|
|
ret = (*fences)->error;
|
|
if (ret)
|
|
break;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* i915_deps_add_dependency - Add a fence to the dependency collection
|
|
* @deps: Pointer to the i915_deps structure a fence is to be added to.
|
|
* @fence: The fence to add.
|
|
* @ctx: Pointer to a struct ttm_operation_ctx indicating how waits are to
|
|
* be performed if waiting.
|
|
*
|
|
* Adds a fence to the dependency collection, and takes a reference on it.
|
|
* If the fence context is not zero and there was a later fence from the
|
|
* same fence context already added, then the fence is not added to the
|
|
* dependency collection. If the fence context is not zero and there was
|
|
* an earlier fence already added, then the fence will replace the older
|
|
* fence from the same context and the reference on the earlier fence will
|
|
* be dropped.
|
|
* If there is a failure to allocate memory to accommodate the new fence to
|
|
* be added, the new fence will instead be waited for and an error may
|
|
* be returned; depending on the value of @ctx, or if there was a fence
|
|
* error. If an error was returned, the dependency collection will be
|
|
* finalized and all fence reference dropped.
|
|
*
|
|
* Return: 0 if success. Negative error code on error.
|
|
*/
|
|
int i915_deps_add_dependency(struct i915_deps *deps,
|
|
struct dma_fence *fence,
|
|
const struct ttm_operation_ctx *ctx)
|
|
{
|
|
unsigned int i;
|
|
int ret;
|
|
|
|
if (!fence)
|
|
return 0;
|
|
|
|
if (dma_fence_is_signaled(fence)) {
|
|
ret = fence->error;
|
|
if (ret)
|
|
i915_deps_fini(deps);
|
|
return ret;
|
|
}
|
|
|
|
for (i = 0; i < deps->num_deps; ++i) {
|
|
struct dma_fence *entry = deps->fences[i];
|
|
|
|
if (!entry->context || entry->context != fence->context)
|
|
continue;
|
|
|
|
if (dma_fence_is_later(fence, entry)) {
|
|
dma_fence_put(entry);
|
|
deps->fences[i] = dma_fence_get(fence);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
return i915_deps_grow(deps, fence, ctx);
|
|
}
|
|
|
|
/**
|
|
* i915_deps_add_resv - Add the fences of a reservation object to a dependency
|
|
* collection.
|
|
* @deps: Pointer to the i915_deps structure a fence is to be added to.
|
|
* @resv: The reservation object, then fences of which to add.
|
|
* @ctx: Pointer to a struct ttm_operation_ctx indicating how waits are to
|
|
* be performed if waiting.
|
|
*
|
|
* Calls i915_deps_add_depencency() on the indicated fences of @resv.
|
|
*
|
|
* Return: Zero on success. Negative error code on error.
|
|
*/
|
|
int i915_deps_add_resv(struct i915_deps *deps, struct dma_resv *resv,
|
|
const struct ttm_operation_ctx *ctx)
|
|
{
|
|
struct dma_resv_iter iter;
|
|
struct dma_fence *fence;
|
|
|
|
dma_resv_assert_held(resv);
|
|
dma_resv_for_each_fence(&iter, resv, true, fence) {
|
|
int ret = i915_deps_add_dependency(deps, fence, ctx);
|
|
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|