[PATCH 1/3] drm/i915/execlists: Microoptimise execlists_cancel_port_request()

Chris Wilson
2017-09-25T12:49:39Z

Just rearrange the code slightly to trim the number of iterations
required.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
drivers/gpu/drm/i915/intel_lrc.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 3623403a4f2d..2c07f3c08bd3 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -571,14 +571,17 @@ static void execlists_dequeue(struct intel_engine_cs *engine)
execlists_submit_ports(engine);
}

-static void execlist_cancel_port_requests(struct intel_engine_execlists *execlists)
+static void
+execlist_cancel_port_requests(struct intel_engine_execlists *execlists)
{
- unsigned int i;
-
- for (i = 0; i < ARRAY_SIZE(execlists->port); i++)
- i915_gem_request_put(port_request(&execlists->port[i]));
+ struct execlist_port *port = execlists->port;
+ unsigned int num_ports = ARRAY_SIZE(execlists->port);

- memset(execlists->port, 0, sizeof(execlists->port));
+ while (num_ports-- && port_isset(port)) {
+ i915_gem_request_put(port_request(port));
+ memset(port, 0, sizeof(*port));
+ port++;
+ }
}

static void execlists_cancel_requests(struct intel_engine_cs *engine)
@@ -625,7 +628,7 @@ static void execlists_cancel_requests(struct intel_engine_cs *engine)

execlists->queue = RB_ROOT;
execlists->first = NULL;
- GEM_BUG_ON(port_isset(&execlists->port[0]));
+ GEM_BUG_ON(port_isset(execlists->port));

/*
* The port is checked prior to scheduling a tasklet, but
--
2.14.1