habanalabs: refactor fence handling in hl_cs_poll_fences

To avoid checking if fence exists multipled times, changed fence handling to depend only on the fence status field: Busy, which means CS still did not completed : Add its QID so multi CS wait on its completion. Finished, which means CS completed and fence exists: Raise its completion bit if it finished mcs handling and update if necessary the earliest timestamp. Gone, which means CS already completed and fence deleted: Update multi CS data to ignore timestamp and raise its completion bit.

Dani Liberman committed 5 years ago

Commit b2faac31 parent fae13261 file · +36 −35Browse files

Unified · Split

drivers/misc/habanalabs/common/command_submission.c+36−35

@@ -2382,47 +2382,48 @@ static int hl_cs_poll_fences(struct multi_cs_data *mcs_data) · 2381 unmodified lines
2382	2382	break;
2383	2383	}
2384	2384
2385		− /*
2386		− * It is possible to get an old sequence numbers from user
2387		− * which related to already completed CSs and their fences
2388		− * already gone. In this case, no need to consider its QID for
2389		− * mcs completion.
2390		− */
2391		− if (fence)
	2385	+ switch (status) {
	2386	+ case CS_WAIT_STATUS_BUSY:
	2387	+ /* CS did not finished, keep waiting on its QID*/
2392	2388	mcs_data->stream_master_qid_map \|=
2393	2389	fence->stream_master_qid_map;
	2390	+ break;
	2391	+ case CS_WAIT_STATUS_COMPLETED:
	2392	+ /*
	2393	+ * Using mcs_handling_done to avoid possibility of mcs_data
	2394	+ * returns to user indicating CS completed before it finished
	2395	+ * all of its mcs handling, to avoid race the next time the
	2396	+ * user waits for mcs.
	2397	+ */
	2398	+ if (!fence->mcs_handling_done)
	2399	+ break;
2394	2400
2395		− /*
2396		− * Using mcs_handling_done to avoid possibility of mcs_data
2397		− * returns to user indicating CS completed before it finished
2398		− * all of its mcs handling, to avoid race the next time the
2399		− * user waits for mcs.
2400		− */
2401		− if (status == CS_WAIT_STATUS_BUSY \|\|
2402		− (fence && !fence->mcs_handling_done))
2403		− continue;
2404		−
2405		− mcs_data->completion_bitmap \|= BIT(i);
2406		−
2407		− /*
2408		− * best effort to extract timestamp. few notes:
2409		− * - if even single fence is gone we cannot extract timestamp
2410		− * (as fence not exist anymore)
2411		− * - for all completed CSs we take the earliest timestamp.
2412		− * for this we have to validate that:
2413		− * 1. given timestamp was indeed set
2414		− * 2. the timestamp is earliest of all timestamps so far
2415		− */
2416		−
2417		− if (status == CS_WAIT_STATUS_GONE) {
	2401	+ mcs_data->completion_bitmap \|= BIT(i);
	2402	+ /*
	2403	+ * For all completed CSs we take the earliest timestamp.
	2404	+ * For this we have to validate that the timestamp is
	2405	+ * earliest of all timestamps so far.
	2406	+ */
	2407	+ if (mcs_data->update_ts &&
	2408	+ (ktime_compare(fence->timestamp, first_cs_time) < 0))
	2409	+ first_cs_time = fence->timestamp;
	2410	+ break;
	2411	+ case CS_WAIT_STATUS_GONE:
2418	2412	mcs_data->update_ts = false;
2419	2413	mcs_data->gone_cs = true;
2420		− } else if (mcs_data->update_ts &&
2421		− (ktime_compare(fence->timestamp,
2422		− ktime_set(0, 0)) > 0) &&
2423		− (ktime_compare(fence->timestamp, first_cs_time) < 0)) {
2424		− first_cs_time = fence->timestamp;
	2414	+ /*
	2415	+ * It is possible to get an old sequence numbers from user
	2416	+ * which related to already completed CSs and their fences
	2417	+ * already gone. In this case, CS set as completed but
	2418	+ * no need to consider its QID for mcs completion.
	2419	+ */
	2420	+ mcs_data->completion_bitmap \|= BIT(i);
	2421	+ break;
	2422	+ default:
	2423	+ dev_err(hdev->dev, "Invalid fence status\n");
	2424	+ return -EINVAL;
2425	2425	}
	2426	+
2426	2427	}
2427	2428
2428	2429	hl_fences_put(mcs_data->fence_arr, arr_len);