diff options
| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2018-03-27 11:23:54 +0300 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2018-03-28 18:07:36 +0300 |
| commit | ae358dacd217370cc362f1674712c4e9246ace8d (patch) | |
| tree | 049bc8fbf62f7ef091087ee0e5d9d017ebbfc116 /drivers/gpu/drm/udl/udl_dmabuf.c | |
| parent | fcb1e57f79c0ecf4c85fecd2294a469367cbddd0 (diff) | |
| download | linux-ae358dacd217370cc362f1674712c4e9246ace8d.tar.xz | |
drm/udl: Get rid of dev->struct_mutex usage
It's only used to protect our page list, and only when we know we have
a full reference. This means none of these code paths can ever race
with the final unref, and hence we do not need dev->struct_mutex
serialization and can simply switch to our own locking.
For more context the only magic the locked gem_free_object provides is
that it prevents concurrent final unref (and destruction) of gem
objects while anyone is holding dev->struct_mutex. This was used by
i915 (and other drivers) to implement eviction handling with less
headaches.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180327082356.24516-3-daniel.vetter@ffwll.ch
Diffstat (limited to 'drivers/gpu/drm/udl/udl_dmabuf.c')
| -rw-r--r-- | drivers/gpu/drm/udl/udl_dmabuf.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/gpu/drm/udl/udl_dmabuf.c b/drivers/gpu/drm/udl/udl_dmabuf.c index 2867ed155ff6..0a20695eb120 100644 --- a/drivers/gpu/drm/udl/udl_dmabuf.c +++ b/drivers/gpu/drm/udl/udl_dmabuf.c @@ -76,6 +76,7 @@ static struct sg_table *udl_map_dma_buf(struct dma_buf_attachment *attach, struct udl_drm_dmabuf_attachment *udl_attach = attach->priv; struct udl_gem_object *obj = to_udl_bo(attach->dmabuf->priv); struct drm_device *dev = obj->base.dev; + struct udl_device *udl = dev->dev_private; struct scatterlist *rd, *wr; struct sg_table *sgt = NULL; unsigned int i; @@ -112,7 +113,7 @@ static struct sg_table *udl_map_dma_buf(struct dma_buf_attachment *attach, return ERR_PTR(-ENOMEM); } - mutex_lock(&dev->struct_mutex); + mutex_lock(&udl->gem_lock); rd = obj->sg->sgl; wr = sgt->sgl; @@ -137,7 +138,7 @@ static struct sg_table *udl_map_dma_buf(struct dma_buf_attachment *attach, attach->priv = udl_attach; err_unlock: - mutex_unlock(&dev->struct_mutex); + mutex_unlock(&udl->gem_lock); return sgt; } |