Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
drm/xe: Use usleep_range for accurate long-running workload timeslicing
msleep is not very accurate in terms of how long it actually sleeps,
whereas usleep_range is precise. Replace the timeslice sleep for
long-running workloads with the more accurate usleep_range to avoid
jitter if the sleep period is less than 20ms.
Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patch.msgid.link/20251212182847.1683222-3-matthew.brost@intel.com
+19
-1
+19
-1
drivers/gpu/drm/xe/xe_guc_submit.c
+19
-1
drivers/gpu/drm/xe/xe_guc_submit.c
···
990
990
return (WQ_SIZE - q->guc->wqi_tail);
991
991
}
992
992
993
+
static inline void relaxed_ms_sleep(unsigned int delay_ms)
994
+
{
995
+
unsigned long min_us, max_us;
996
+
997
+
if (!delay_ms)
998
+
return;
999
+
1000
+
if (delay_ms > 20) {
1001
+
msleep(delay_ms);
1002
+
return;
1003
+
}
1004
+
1005
+
min_us = mul_u32_u32(delay_ms, 1000);
1006
+
max_us = min_us + 500;
1007
+
1008
+
usleep_range(min_us, max_us);
1009
+
}
1010
+
993
1011
static int wq_wait_for_space(struct xe_exec_queue *q, u32 wqi_size)
994
1012
{
995
1013
struct xe_guc *guc = exec_queue_to_guc(q);
···
1921
1903
since_resume_ms;
1922
1904
1923
1905
if (wait_ms > 0 && q->guc->resume_time)
1924
-
msleep(wait_ms);
1906
+
relaxed_ms_sleep(wait_ms);
1925
1907
1926
1908
set_exec_queue_suspended(q);
1927
1909
disable_scheduling(q, false);