[03/38] net/sfc/base: ensure EvQ poll stops when abort is requested

Message ID 1549556983-10896-4-git-send-email-arybchenko@solarflare.com (mailing list archive)
State Accepted, archived
Delegated to: Ferruh Yigit
Headers
Series net/sfc: update base driver |

Checks

Context Check Description
ci/checkpatch warning coding style issues

Commit Message

Andrew Rybchenko Feb. 7, 2019, 4:29 p.m. UTC
  From: Mark Spender <mspender@solarflare.com>

If an event handler requested an abort, only the inner loop was
guarenteed to be broken out of - the outer loop could continue
if total == batch.

Fix this by poisoning batch to ensure it is different to total.

Signed-off-by: Mark Spender <mspender@solarflare.com>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
---
 drivers/net/sfc/base/efx_ev.c | 8 ++++++++
 1 file changed, 8 insertions(+)
  

Patch

diff --git a/drivers/net/sfc/base/efx_ev.c b/drivers/net/sfc/base/efx_ev.c
index 1139cc26f..907c4249f 100644
--- a/drivers/net/sfc/base/efx_ev.c
+++ b/drivers/net/sfc/base/efx_ev.c
@@ -480,6 +480,14 @@  efx_ev_qpoll(
 			if (should_abort) {
 				/* Ignore subsequent events */
 				total = index + 1;
+
+				/*
+				 * Poison batch to ensure the outer
+				 * loop is broken out of.
+				 */
+				EFSYS_ASSERT(batch <= EFX_EV_BATCH);
+				batch += (EFX_EV_BATCH << 1);
+				EFSYS_ASSERT(total != batch);
 				break;
 			}
 		}