diff options
| author | Chris Wilson <chris@chris-wilson.co.uk> | 2020-03-09 15:42:49 +0100 |
|---|---|---|
| committer | Chris Wilson <chris@chris-wilson.co.uk> | 2020-03-09 18:08:58 +0100 |
| commit | 23a44ae9e8540032a92921a434c97354cbb68785 (patch) | |
| tree | 10ad7ee3ab55e26729d2a9b0eb41c21af8496035 | |
| parent | drm/i915: Mark racy read of intel_engine_cs.saturated (diff) | |
| download | linux-23a44ae9e8540032a92921a434c97354cbb68785.tar.xz linux-23a44ae9e8540032a92921a434c97354cbb68785.zip | |
drm/i915/execlists: Mark up the racy access to switch_priority_hint
[ 7534.150687] BUG: KCSAN: data-race in __execlists_submission_tasklet [i915] / process_csb [i915]
[ 7534.150706]
[ 7534.150717] write to 0xffff8881f1bc24b4 of 4 bytes by task 24404 on cpu 3:
[ 7534.150925] __execlists_submission_tasklet+0x1158/0x2780 [i915]
[ 7534.151133] execlists_submit_request+0x2e8/0x2f0 [i915]
[ 7534.151348] submit_notify+0x8f/0xc0 [i915]
[ 7534.151549] __i915_sw_fence_complete+0x5d/0x3e0 [i915]
[ 7534.151753] i915_sw_fence_complete+0x58/0x80 [i915]
[ 7534.151963] i915_sw_fence_commit+0x16/0x20 [i915]
[ 7534.152179] __i915_request_queue+0x60/0x70 [i915]
[ 7534.152388] i915_gem_do_execbuffer+0x3997/0x4c20 [i915]
[ 7534.152598] i915_gem_execbuffer2_ioctl+0x2c3/0x580 [i915]
[ 7534.152615] drm_ioctl_kernel+0xe4/0x120
[ 7534.152629] drm_ioctl+0x297/0x4c7
[ 7534.152642] ksys_ioctl+0x89/0xb0
[ 7534.152654] __x64_sys_ioctl+0x42/0x60
[ 7534.152667] do_syscall_64+0x6e/0x2c0
[ 7534.152681] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 7534.152693]
[ 7534.152703] read to 0xffff8881f1bc24b4 of 4 bytes by interrupt on cpu 2:
[ 7534.152914] process_csb+0xe7c/0x10a0 [i915]
[ 7534.153120] execlists_submission_tasklet+0x30/0x170 [i915]
[ 7534.153138] tasklet_action_common.isra.0+0x42/0xa0
[ 7534.153153] __do_softirq+0xd7/0x2cd
[ 7534.153166] run_ksoftirqd+0x15/0x20
[ 7534.153180] smpboot_thread_fn+0x1ab/0x300
[ 7534.153194] kthread+0x19a/0x1e0
[ 7534.153207] ret_from_fork+0x1f/0x30
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200309144249.10309-1-chris@chris-wilson.co.uk
| -rw-r--r-- | drivers/gpu/drm/i915/gt/intel_lrc.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c index a1d268880cfe..b5149e471e1d 100644 --- a/drivers/gpu/drm/i915/gt/intel_lrc.c +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c @@ -1782,12 +1782,13 @@ timeslice(const struct intel_engine_cs *engine) static unsigned long active_timeslice(const struct intel_engine_cs *engine) { - const struct i915_request *rq = *engine->execlists.active; + const struct intel_engine_execlists *execlists = &engine->execlists; + const struct i915_request *rq = *execlists->active; if (!rq || i915_request_completed(rq)) return 0; - if (engine->execlists.switch_priority_hint < effective_prio(rq)) + if (READ_ONCE(execlists->switch_priority_hint) < effective_prio(rq)) return 0; return timeslice(engine); @@ -1804,8 +1805,11 @@ static void set_timeslice(struct intel_engine_cs *engine) static void start_timeslice(struct intel_engine_cs *engine) { struct intel_engine_execlists *execlists = &engine->execlists; + int prio = queue_prio(execlists); - execlists->switch_priority_hint = execlists->queue_priority_hint; + WRITE_ONCE(execlists->switch_priority_hint, prio); + if (prio == INT_MIN) + return; if (timer_pending(&execlists->timer)) return; @@ -5330,10 +5334,10 @@ void intel_execlists_show_requests(struct intel_engine_cs *engine, if (execlists->switch_priority_hint != INT_MIN) drm_printf(m, "\t\tSwitch priority hint: %d\n", - execlists->switch_priority_hint); + READ_ONCE(execlists->switch_priority_hint)); if (execlists->queue_priority_hint != INT_MIN) drm_printf(m, "\t\tQueue priority hint: %d\n", - execlists->queue_priority_hint); + READ_ONCE(execlists->queue_priority_hint)); last = NULL; count = 0; |