diff options
author | Chris Wilson <chris@chris-wilson.co.uk> | 2019-10-04 14:40:00 +0100 |
---|---|---|
committer | Chris Wilson <chris@chris-wilson.co.uk> | 2019-10-04 15:39:12 +0100 |
commit | b1e3177bd1d8f41e2a9cc847e56a96cdc0eefe62 (patch) | |
tree | 9af22565533f12868a015e18e51406d54773e08a /drivers/gpu/drm/i915/gem/i915_gem_pm.c | |
parent | 274cbf20fd108fa26d0497282b102e00371210fd (diff) |
drm/i915: Coordinate i915_active with its own mutex
Forgo the struct_mutex serialisation for i915_active, and interpose its
own mutex handling for active/retire.
This is a multi-layered sleight-of-hand. First, we had to ensure that no
active/retire callbacks accidentally inverted the mutex ordering rules,
nor assumed that they were themselves serialised by struct_mutex. More
challenging though, is the rule over updating elements of the active
rbtree. Instead of the whole i915_active now being serialised by
struct_mutex, allocations/rotations of the tree are serialised by the
i915_active.mutex and individual nodes are serialised by the caller
using the i915_timeline.mutex (we need to use nested spinlocks to
interact with the dma_fence callback lists).
The pain point here is that instead of a single mutex around execbuf, we
now have to take a mutex for active tracker (one for each vma, context,
etc) and a couple of spinlocks for each fence update. The improvement in
fine grained locking allowing for multiple concurrent clients
(eventually!) should be worth it in typical loads.
v2: Add some comments that barely elucidate anything :(
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-6-chris@chris-wilson.co.uk
Diffstat (limited to 'drivers/gpu/drm/i915/gem/i915_gem_pm.c')
-rw-r--r-- | drivers/gpu/drm/i915/gem/i915_gem_pm.c | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pm.c b/drivers/gpu/drm/i915/gem/i915_gem_pm.c index cca192ecff8b..0a4115c6c275 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_pm.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_pm.c @@ -16,14 +16,11 @@ static void call_idle_barriers(struct intel_engine_cs *engine) struct llist_node *node, *next; llist_for_each_safe(node, next, llist_del_all(&engine->barrier_tasks)) { - struct i915_active_request *active = + struct dma_fence_cb *cb = container_of((struct list_head *)node, - typeof(*active), link); + typeof(*cb), node); - INIT_LIST_HEAD(&active->link); - RCU_INIT_POINTER(active->request, NULL); - - active->retire(active, NULL); + cb->func(NULL, cb); } } |