git: 0a9d1da6e6ce - main - cxgbe(4): Stop work request queues in a reliable manner.

The branch main has been updated by np:

URL: https://cgit.FreeBSD.org/src/commit/?id=0a9d1da6e6cede5e9c0ff63240d724049ad72b5b

commit 0a9d1da6e6cede5e9c0ff63240d724049ad72b5b
Author:     Navdeep Parhar <np@FreeBSD.org>
AuthorDate: 2024-07-31 19:27:18 +0000
Commit:     Navdeep Parhar <np@FreeBSD.org>
CommitDate: 2024-08-17 18:23:32 +0000

    cxgbe(4): Stop work request queues in a reliable manner.
    
    Clear the EQ_HW_ALLOCATED flag with the wrq lock held and discard all
    work requests, pending or new, when it's not set.
    
    MFC after:      1 week
    Sponsored by:   Chelsio Communications
---
 sys/dev/cxgbe/adapter.h |  5 ++++-
 sys/dev/cxgbe/t4_main.c | 20 +++++++++++++++++++-
 sys/dev/cxgbe/t4_sge.c  | 15 ++++++++++++++-
 3 files changed, 37 insertions(+), 3 deletions(-)

diff --git a/sys/dev/cxgbe/adapter.h b/sys/dev/cxgbe/adapter.h
index 0d731e736823..3922bd3909fe 100644
--- a/sys/dev/cxgbe/adapter.h
+++ b/sys/dev/cxgbe/adapter.h
@@ -1561,7 +1561,10 @@ t4_wrq_tx(struct adapter *sc, struct wrqe *wr)
 	struct sge_wrq *wrq = wr->wrq;
 
 	TXQ_LOCK(wrq);
-	t4_wrq_tx_locked(sc, wrq, wr);
+	if (__predict_true(wrq->eq.flags & EQ_HW_ALLOCATED))
+		t4_wrq_tx_locked(sc, wrq, wr);
+	else
+		free(wr, M_CXGBE);
 	TXQ_UNLOCK(wrq);
 }
 
diff --git a/sys/dev/cxgbe/t4_main.c b/sys/dev/cxgbe/t4_main.c
index 795c8d7e2e37..57c1eeceab22 100644
--- a/sys/dev/cxgbe/t4_main.c
+++ b/sys/dev/cxgbe/t4_main.c
@@ -2060,7 +2060,9 @@ stop_lld(struct adapter *sc)
 			}
 #if defined(TCP_OFFLOAD) || defined(RATELIMIT)
 			for_each_ofld_txq(vi, k, ofld_txq) {
+				TXQ_LOCK(&ofld_txq->wrq);
 				ofld_txq->wrq.eq.flags &= ~EQ_HW_ALLOCATED;
+				TXQ_UNLOCK(&ofld_txq->wrq);
 			}
 #endif
 			for_each_rxq(vi, k, rxq) {
@@ -2078,7 +2080,9 @@ stop_lld(struct adapter *sc)
 		if (sc->flags & FULL_INIT_DONE) {
 			/* Control queue */
 			wrq = &sc->sge.ctrlq[i];
+			TXQ_LOCK(wrq);
 			wrq->eq.flags &= ~EQ_HW_ALLOCATED;
+			TXQ_UNLOCK(wrq);
 			quiesce_wrq(wrq);
 		}
 	}
@@ -7047,8 +7051,22 @@ quiesce_txq(struct sge_txq *txq)
 static void
 quiesce_wrq(struct sge_wrq *wrq)
 {
+	struct wrqe *wr;
 
-	/* XXXTX */
+	TXQ_LOCK(wrq);
+	while ((wr = STAILQ_FIRST(&wrq->wr_list)) != NULL) {
+		STAILQ_REMOVE_HEAD(&wrq->wr_list, link);
+#ifdef INVARIANTS
+		wrq->nwr_pending--;
+		wrq->ndesc_needed -= howmany(wr->wr_len, EQ_ESIZE);
+#endif
+		free(wr, M_CXGBE);
+	}
+	MPASS(wrq->nwr_pending == 0);
+	MPASS(wrq->ndesc_needed == 0);
+	wrq->nwr_pending = 0;
+	wrq->ndesc_needed = 0;
+	TXQ_UNLOCK(wrq);
 }
 
 static void
diff --git a/sys/dev/cxgbe/t4_sge.c b/sys/dev/cxgbe/t4_sge.c
index b4eb0701821a..bc81a0251deb 100644
--- a/sys/dev/cxgbe/t4_sge.c
+++ b/sys/dev/cxgbe/t4_sge.c
@@ -2921,6 +2921,10 @@ start_wrq_wr(struct sge_wrq *wrq, int len16, struct wrq_cookie *cookie)
 	MPASS(ndesc > 0 && ndesc <= SGE_MAX_WR_NDESC);
 
 	EQ_LOCK(eq);
+	if (__predict_false((eq->flags & EQ_HW_ALLOCATED) == 0)) {
+		EQ_UNLOCK(eq);
+		return (NULL);
+	}
 
 	if (TAILQ_EMPTY(&wrq->incomplete_wrs) && !STAILQ_EMPTY(&wrq->wr_list))
 		drain_wrq_wr_list(sc, wrq);
@@ -3016,7 +3020,10 @@ commit_wrq_wr(struct sge_wrq *wrq, void *w, struct wrq_cookie *cookie)
 				    F_FW_WR_EQUEQ);
 			}
 
-			ring_eq_db(wrq->adapter, eq, ndesc);
+			if (__predict_true(eq->flags & EQ_HW_ALLOCATED))
+				ring_eq_db(wrq->adapter, eq, ndesc);
+			else
+				IDXINCR(eq->dbidx, ndesc, eq->sidx);
 		} else {
 			MPASS(IDXDIFF(next->pidx, pidx, eq->sidx) == ndesc);
 			next->pidx = pidx;
@@ -3852,6 +3859,8 @@ alloc_ctrlq(struct adapter *sc, int idx)
 
 	if (!(ctrlq->eq.flags & EQ_HW_ALLOCATED)) {
 		MPASS(ctrlq->eq.flags & EQ_SW_ALLOCATED);
+		MPASS(ctrlq->nwr_pending == 0);
+		MPASS(ctrlq->ndesc_needed == 0);
 
 		rc = alloc_eq_hwq(sc, NULL, &ctrlq->eq);
 		if (rc != 0) {
@@ -4554,6 +4563,7 @@ free_wrq(struct adapter *sc, struct sge_wrq *wrq)
 {
 	free_eq(sc, &wrq->eq);
 	MPASS(wrq->nwr_pending == 0);
+	MPASS(wrq->ndesc_needed == 0);
 	MPASS(TAILQ_EMPTY(&wrq->incomplete_wrs));
 	MPASS(STAILQ_EMPTY(&wrq->wr_list));
 	bzero(wrq, sizeof(*wrq));
@@ -4848,6 +4858,9 @@ alloc_ofld_txq(struct vi_info *vi, struct sge_ofld_txq *ofld_txq, int idx)
 	}
 
 	if (!(eq->flags & EQ_HW_ALLOCATED)) {
+		MPASS(eq->flags & EQ_SW_ALLOCATED);
+		MPASS(ofld_txq->wrq.nwr_pending == 0);
+		MPASS(ofld_txq->wrq.ndesc_needed == 0);
 		rc = alloc_eq_hwq(sc, vi, eq);
 		if (rc != 0) {
 			CH_ERR(vi, "failed to create hw ofld_txq%d: %d\n", idx,