drm/i915/gt: Drop atomic for engine->fw_active tracking

Since schedule-in/out is now entirely serialised by the tasklet bitlock,
we do not need to worry about concurrent in/out operations and so reduce
the atomic operations to plain instructions.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210115142331.24458-1-chris@chris-wilson.co.uk
This commit is contained in:
Chris Wilson 2021-01-15 14:23:27 +00:00
parent 0bd080497b
commit 2c421896ad
3 changed files with 4 additions and 4 deletions

View File

@ -1676,7 +1676,7 @@ void intel_engine_dump(struct intel_engine_cs *engine,
ktime_to_ms(intel_engine_get_busy_time(engine,
&dummy)));
drm_printf(m, "\tForcewake: %x domains, %d active\n",
engine->fw_domain, atomic_read(&engine->fw_active));
engine->fw_domain, READ_ONCE(engine->fw_active));
rcu_read_lock();
rq = READ_ONCE(engine->heartbeat.systole);

View File

@ -319,7 +319,7 @@ struct intel_engine_cs {
* as possible.
*/
enum forcewake_domains fw_domain;
atomic_t fw_active;
unsigned int fw_active;
unsigned long context_tag;

View File

@ -538,7 +538,7 @@ __execlists_schedule_in(struct i915_request *rq)
ce->lrc.ccid |= engine->execlists.ccid;
__intel_gt_pm_get(engine->gt);
if (engine->fw_domain && !atomic_fetch_inc(&engine->fw_active))
if (engine->fw_domain && !engine->fw_active++)
intel_uncore_forcewake_get(engine->uncore, engine->fw_domain);
execlists_context_status_change(rq, INTEL_CONTEXT_SCHEDULE_IN);
intel_engine_context_in(engine);
@ -645,7 +645,7 @@ static void __execlists_schedule_out(struct i915_request * const rq,
lrc_update_runtime(ce);
intel_engine_context_out(engine);
execlists_context_status_change(rq, INTEL_CONTEXT_SCHEDULE_OUT);
if (engine->fw_domain && !atomic_dec_return(&engine->fw_active))
if (engine->fw_domain && !--engine->fw_active)
intel_uncore_forcewake_put(engine->uncore, engine->fw_domain);
intel_gt_pm_put_async(engine->gt);