lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20220930162903.62262-6-saeed@kernel.org>
Date:   Fri, 30 Sep 2022 09:28:52 -0700
From:   Saeed Mahameed <saeed@...nel.org>
To:     "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>,
        Eric Dumazet <edumazet@...gle.com>
Cc:     Saeed Mahameed <saeedm@...dia.com>, netdev@...r.kernel.org,
        Tariq Toukan <tariqt@...dia.com>,
        Maxim Mikityanskiy <maximmi@...dia.com>
Subject: [PATCH net-next 05/16] net/mlx5e: Use partial batches in legacy RQ

From: Maxim Mikityanskiy <maximmi@...dia.com>

Legacy RQ allocates WQEs in batches. If the batch allocation fails, the
pages of the allocated part are released. This commit changes this
behavior to allow to use the pages that have been already allocated.

After this change, we need to be careful about indexing rq->wqe.frags[].
The WQ size is a power of two that divides by wqe_bulk (8), and the old
code used whole bulks, which allowed to use indices [8*K; 8*K+7] without
overflowing. Now that the bulks may be partial, the range can start at
any location (not only at 8*K), so we need to wrap them around to avoid
out-of-bounds array access.

Signed-off-by: Maxim Mikityanskiy <maximmi@...dia.com>
Reviewed-by: Tariq Toukan <tariqt@...dia.com>
Signed-off-by: Saeed Mahameed <saeedm@...dia.com>
---
 .../net/ethernet/mellanox/mlx5/core/en_rx.c   | 39 ++++++++++---------
 1 file changed, 21 insertions(+), 18 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index 72d74de3ee99..ffca217b7d7e 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -427,7 +427,6 @@ static void mlx5e_dealloc_rx_wqe(struct mlx5e_rq *rq, u16 ix)
 static int mlx5e_alloc_rx_wqes(struct mlx5e_rq *rq, u16 ix, u8 wqe_bulk)
 {
 	struct mlx5_wq_cyc *wq = &rq->wqe.wq;
-	int err;
 	int i;
 
 	if (rq->xsk_pool) {
@@ -442,20 +441,16 @@ static int mlx5e_alloc_rx_wqes(struct mlx5e_rq *rq, u16 ix, u8 wqe_bulk)
 	}
 
 	for (i = 0; i < wqe_bulk; i++) {
-		struct mlx5e_rx_wqe_cyc *wqe = mlx5_wq_cyc_get_wqe(wq, ix + i);
+		int j = mlx5_wq_cyc_ctr2ix(wq, ix + i);
+		struct mlx5e_rx_wqe_cyc *wqe;
 
-		err = mlx5e_alloc_rx_wqe(rq, wqe, ix + i);
-		if (unlikely(err))
-			goto free_wqes;
-	}
+		wqe = mlx5_wq_cyc_get_wqe(wq, j);
 
-	return 0;
-
-free_wqes:
-	while (--i >= 0)
-		mlx5e_dealloc_rx_wqe(rq, ix + i);
+		if (unlikely(mlx5e_alloc_rx_wqe(rq, wqe, j)))
+			break;
+	}
 
-	return err;
+	return i;
 }
 
 static inline void
@@ -821,8 +816,8 @@ static void mlx5e_dealloc_rx_mpwqe(struct mlx5e_rq *rq, u16 ix)
 INDIRECT_CALLABLE_SCOPE bool mlx5e_post_rx_wqes(struct mlx5e_rq *rq)
 {
 	struct mlx5_wq_cyc *wq = &rq->wqe.wq;
+	bool busy = false;
 	u8 wqe_bulk;
-	int err;
 
 	if (unlikely(!test_bit(MLX5E_RQ_STATE_ENABLED, &rq->state)))
 		return false;
@@ -837,14 +832,22 @@ INDIRECT_CALLABLE_SCOPE bool mlx5e_post_rx_wqes(struct mlx5e_rq *rq)
 
 	do {
 		u16 head = mlx5_wq_cyc_get_head(wq);
+		int count;
+		u8 bulk;
 
-		err = mlx5e_alloc_rx_wqes(rq, head, wqe_bulk);
-		if (unlikely(err)) {
+		/* Don't allow any newly allocated WQEs to share the same page
+		 * with old WQEs that aren't completed yet. Stop earlier.
+		 */
+		bulk = wqe_bulk - ((head + wqe_bulk) & rq->wqe.info.wqe_index_mask);
+
+		count = mlx5e_alloc_rx_wqes(rq, head, bulk);
+		if (likely(count > 0))
+			mlx5_wq_cyc_push_n(wq, count);
+		if (unlikely(count != bulk)) {
 			rq->stats->buff_alloc_err++;
+			busy = true;
 			break;
 		}
-
-		mlx5_wq_cyc_push_n(wq, wqe_bulk);
 	} while (mlx5_wq_cyc_missing(wq) >= wqe_bulk);
 
 	/* ensure wqes are visible to device before updating doorbell record */
@@ -852,7 +855,7 @@ INDIRECT_CALLABLE_SCOPE bool mlx5e_post_rx_wqes(struct mlx5e_rq *rq)
 
 	mlx5_wq_cyc_update_db_record(wq);
 
-	return !!err;
+	return busy;
 }
 
 void mlx5e_free_icosq_descs(struct mlx5e_icosq *sq)
-- 
2.37.3

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ