On Mon, Jan 24, 2022 at 01:25:08PM +0100, Christian König wrote:
> Instead of duplicating that at different places add an iterator over all
> the resources in a resource manager.
>
> Signed-off-by: Christian König <christian.koenig@xxxxxxx>
> ---
> drivers/gpu/drm/ttm/ttm_bo.c | 41 +++++++++++----------------
> drivers/gpu/drm/ttm/ttm_device.c | 26 ++++++++---------
> drivers/gpu/drm/ttm/ttm_resource.c | 45 ++++++++++++++++++++++++++++++
> include/drm/ttm/ttm_resource.h | 23 +++++++++++++++
> 4 files changed, 95 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
> index cb0fa932d495..599be3dda8a9 100644
> --- a/drivers/gpu/drm/ttm/ttm_bo.c
> +++ b/drivers/gpu/drm/ttm/ttm_bo.c
> @@ -579,38 +579,29 @@ int ttm_mem_evict_first(struct ttm_device *bdev,
> struct ww_acquire_ctx *ticket)
> {
> struct ttm_buffer_object *bo = NULL, *busy_bo = NULL;
> + struct ttm_resource_cursor cursor;
> struct ttm_resource *res;
> bool locked = false;
> - unsigned i;
> int ret;
>
> spin_lock(&bdev->lru_lock);
> - for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
> - list_for_each_entry(res, &man->lru[i], lru) {
> - bool busy;
> -
> - bo = res->bo;
> - if (!ttm_bo_evict_swapout_allowable(bo, ctx, place,
> - &locked, &busy)) {
> - if (busy && !busy_bo && ticket !=
> - dma_resv_locking_ctx(bo->base.resv))
> - busy_bo = bo;
> - continue;
> - }
> -
> - if (!ttm_bo_get_unless_zero(bo)) {
> - if (locked)
> - dma_resv_unlock(bo->base.resv);
> - continue;
> - }
> - break;
> + ttm_resource_manager_for_each_res(man, &cursor, res) {
> + bool busy;
> +
> + if (!ttm_bo_evict_swapout_allowable(res->bo, ctx, place,
> + &locked, &busy)) {
> + if (busy && !busy_bo && ticket !=
> + dma_resv_locking_ctx(bo->base.resv))
> + busy_bo = res->bo;
> + continue;
> }
>
> - /* If the inner loop terminated early, we have our candidate */
> - if (&res->lru != &man->lru[i])
> - break;
> -
> - bo = NULL;
> + if (!ttm_bo_get_unless_zero(res->bo)) {
> + if (locked)
> + dma_resv_unlock(res->bo->base.resv);
> + continue;
> + }
> + bo = res->bo;
> }
>
> if (!bo) {
> diff --git a/drivers/gpu/drm/ttm/ttm_device.c b/drivers/gpu/drm/ttm/ttm_device.c
> index ba35887147ba..a0562ab386f5 100644
> --- a/drivers/gpu/drm/ttm/ttm_device.c
> +++ b/drivers/gpu/drm/ttm/ttm_device.c
> @@ -142,10 +142,10 @@ EXPORT_SYMBOL(ttm_global_swapout);
> int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
> gfp_t gfp_flags)
> {
> + struct ttm_resource_cursor cursor;
> struct ttm_resource_manager *man;
> - struct ttm_buffer_object *bo;
> struct ttm_resource *res;
> - unsigned i, j;
> + unsigned i;
> int ret;
>
> spin_lock(&bdev->lru_lock);
> @@ -154,20 +154,16 @@ int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
> if (!man || !man->use_tt)
> continue;
>
> - for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j) {
> - list_for_each_entry(res, &man->lru[j], lru) {
> - uint32_t num_pages;
> -
> - bo = res->bo;
> - num_pages = PFN_UP(bo->base.size);
> + ttm_resource_manager_for_each_res(man, &cursor, res) {
> + struct ttm_buffer_object *bo = res->bo;
> + uint32_t num_pages = PFN_UP(bo->base.size);
>
> - ret = ttm_bo_swapout(bo, ctx, gfp_flags);
> - /* ttm_bo_swapout has dropped the lru_lock */
> - if (!ret)
> - return num_pages;
> - if (ret != -EBUSY)
> - return ret;
> - }
> + ret = ttm_bo_swapout(bo, ctx, gfp_flags);
> + /* ttm_bo_swapout has dropped the lru_lock */
> + if (!ret)
> + return num_pages;
> + if (ret != -EBUSY)
> + return ret;
> }
> }
> spin_unlock(&bdev->lru_lock);
> diff --git a/drivers/gpu/drm/ttm/ttm_resource.c b/drivers/gpu/drm/ttm/ttm_resource.c
> index 450e665c357b..9e68d36a1546 100644
> --- a/drivers/gpu/drm/ttm/ttm_resource.c
> +++ b/drivers/gpu/drm/ttm/ttm_resource.c
> @@ -354,6 +354,51 @@ void ttm_resource_manager_debug(struct ttm_resource_manager *man,
> }
> EXPORT_SYMBOL(ttm_resource_manager_debug);
>
> +/**
> + * ttm_resource_manager_first
> + *
> + * @man: resource manager to iterate over
> + * @cursor: cursor to record the position
> + *
> + * Returns the first resource from the resource manager.
> + */
> +struct ttm_resource *
> +ttm_resource_manager_first(struct ttm_resource_manager *man,
> + struct ttm_resource_cursor *cursor)
> +{
> + struct ttm_resource *res;
assert_lockdep_held for the lru spinlock here and in the _next() one pls,
just to be on the safe side.
> +
> + for (cursor->priority = 0; cursor->priority < TTM_MAX_BO_PRIORITY;
> + ++cursor->priority)
> + list_for_each_entry(res, &man->lru[cursor->priority], lru)
> + return res;
> +
> + return NULL;
> +}
> +
> +/**
> + * ttm_resource_manager_next
> + *
> + * @man: resource manager to iterate over
> + * @cursor: cursor to record the position
> + *
> + * Returns the next resource from the resource manager.
> + */
> +struct ttm_resource *
> +ttm_resource_manager_next(struct ttm_resource_manager *man,
> + struct ttm_resource_cursor *cursor,
> + struct ttm_resource *res)
> +{
> + list_for_each_entry_continue(res, &man->lru[cursor->priority], lru)
> + return res;
> +
> + for (; cursor->priority < TTM_MAX_BO_PRIORITY; ++cursor->priority)
> + list_for_each_entry(res, &man->lru[cursor->priority], lru)
> + return res;
> +
> + return NULL;
> +}
> +
> static void ttm_kmap_iter_iomap_map_local(struct ttm_kmap_iter *iter,
> struct dma_buf_map *dmap,
> pgoff_t i)
> diff --git a/include/drm/ttm/ttm_resource.h b/include/drm/ttm/ttm_resource.h
> index a54d52517a30..13da5e337350 100644
> --- a/include/drm/ttm/ttm_resource.h
> +++ b/include/drm/ttm/ttm_resource.h
> @@ -183,6 +183,17 @@ struct ttm_resource {
> struct list_head lru;
> };
>
> +/**
> + * struct ttm_resource_cursor
> + *
> + * @priority: the current priority
> + *
> + * Cursor to iterate over the resources in a manager.
> + */
> +struct ttm_resource_cursor {
> + unsigned int priority;
> +};
> +
> /**
> * struct ttm_lru_bulk_move_pos
> *
> @@ -339,6 +350,18 @@ int ttm_resource_manager_evict_all(struct ttm_device *bdev,
> void ttm_resource_manager_debug(struct ttm_resource_manager *man,
> struct drm_printer *p);
>
> +struct ttm_resource *
> +ttm_resource_manager_first(struct ttm_resource_manager *man,
> + struct ttm_resource_cursor *cursor);
> +struct ttm_resource *
> +ttm_resource_manager_next(struct ttm_resource_manager *man,
> + struct ttm_resource_cursor *cursor,
> + struct ttm_resource *res);
> +
Kerneldoc for this one would be nice too.
> +#define ttm_resource_manager_for_each_res(man, cursor, res) \
> + for (res = ttm_resource_manager_first(man, cursor); res; \
> + res = ttm_resource_manager_next(man, cursor, res))
> +
> struct ttm_kmap_iter *
> ttm_kmap_iter_iomap_init(struct ttm_kmap_iter_iomap *iter_io,
> struct io_mapping *iomap,
I really like this, looks neat and tidy. With the two nits addressed.
Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
> --
> 2.25.1
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
