[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20221112102147.496378-8-saeed@kernel.org>
Date: Sat, 12 Nov 2022 02:21:39 -0800
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>, Ofer Levi <oferle@...dia.com>
Subject: [net-next 07/15] net/mlx5e: Support enhanced CQE compression
From: Ofer Levi <oferle@...dia.com>
CQE compression feature improves performance by reducing PCI bandwidth
bottleneck on CQEs write.
Enhanced CQE compression introduced in ConnectX-6 and it aims to reduce
CPU utilization of SW side packets decompression by eliminating the
need to rewrite ownership bit, which is likely to cost a cache-miss, is
replaced by validity byte handled solely by HW.
Another advantage of the enhanced feature is that session packets are
available to SW as soon as a single CQE slot is filled, instead of
waiting for session to close, this improves packet latency from NIC to
host.
Performance:
Following are tested scenarios and reults comparing basic and enahnced
CQE compression.
setup: IXIA 100GbE connected directly to port 0 and port 1 of
ConnectX-6 Dx 100GbE dual port.
Case #1 RX only, single flow goes to single queue:
IRQ rate reduced by ~ 30%, CPU utilization improved by 2%.
Case #2 IP forwarding from port 1 to port 0 single flow goes to
single queue:
Avg latency improved from 60us to 21us, frame loss improved from 0.5% to 0.0%.
Case #3 IP forwarding from port 1 to port 0 Max Throughput IXIA sends
100%, 8192 UDP flows, goes to 24 queues:
Enhanced is equal or slightly better than basic.
Testing the basic compression feature with this patch shows there is
no perfrormance degradation of the basic compression feature.
Signed-off-by: Ofer Levi <oferle@...dia.com>
Reviewed-by: Tariq Toukan <tariqt@...dia.com>
Signed-off-by: Saeed Mahameed <saeedm@...dia.com>
---
drivers/net/ethernet/mellanox/mlx5/core/en.h | 2 +
.../ethernet/mellanox/mlx5/core/en/params.c | 10 +-
.../net/ethernet/mellanox/mlx5/core/en_main.c | 8 +
.../net/ethernet/mellanox/mlx5/core/en_rx.c | 150 +++++++++++++++---
drivers/net/ethernet/mellanox/mlx5/core/wq.h | 17 ++
include/linux/mlx5/device.h | 6 +
6 files changed, 170 insertions(+), 23 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index 26a23047f1f3..ff5b302531d5 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -344,6 +344,7 @@ enum {
MLX5E_RQ_STATE_CSUM_FULL, /* cqe_csum_full hw bit is set */
MLX5E_RQ_STATE_MINI_CQE_HW_STRIDX, /* set when mini_cqe_resp_stride_index cap is used */
MLX5E_RQ_STATE_SHAMPO, /* set when SHAMPO cap is used */
+ MLX5E_RQ_STATE_MINI_CQE_ENHANCED, /* set when enhanced mini_cqe_cap is used */
};
struct mlx5e_cq {
@@ -370,6 +371,7 @@ struct mlx5e_cq_decomp {
u8 mini_arr_idx;
u16 left;
u16 wqe_counter;
+ bool last_cqe_title;
} ____cacheline_aligned_in_smp;
enum mlx5e_dma_map_type {
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/params.c b/drivers/net/ethernet/mellanox/mlx5/core/en/params.c
index 29dd3a04c154..1a2de9bc6538 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/params.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/params.c
@@ -608,13 +608,15 @@ void mlx5e_init_rq_type_params(struct mlx5_core_dev *mdev,
MLX5E_PARAMS_MINIMUM_LOG_RQ_SIZE :
MLX5E_PARAMS_DEFAULT_LOG_RQ_SIZE;
- mlx5_core_info(mdev, "MLX5E: StrdRq(%d) RqSz(%ld) StrdSz(%ld) RxCqeCmprss(%d)\n",
+ mlx5_core_info(mdev, "MLX5E: StrdRq(%d) RqSz(%ld) StrdSz(%ld) RxCqeCmprss(%d %s)\n",
params->rq_wq_type == MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ,
params->rq_wq_type == MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ ?
BIT(mlx5e_mpwqe_get_log_rq_size(mdev, params, NULL)) :
BIT(params->log_rq_mtu_frames),
BIT(mlx5e_mpwqe_get_log_stride_size(mdev, params, NULL)),
- MLX5E_GET_PFLAG(params, MLX5E_PFLAG_RX_CQE_COMPRESS));
+ MLX5E_GET_PFLAG(params, MLX5E_PFLAG_RX_CQE_COMPRESS),
+ MLX5_CAP_GEN(mdev, enhanced_cqe_compression) ?
+ "enhanced" : "basic");
}
void mlx5e_set_rq_type(struct mlx5_core_dev *mdev, struct mlx5e_params *params)
@@ -852,6 +854,10 @@ static void mlx5e_build_rx_cq_param(struct mlx5_core_dev *mdev,
if (MLX5E_GET_PFLAG(params, MLX5E_PFLAG_RX_CQE_COMPRESS)) {
MLX5_SET(cqc, cqc, mini_cqe_res_format, hw_stridx ?
MLX5_CQE_FORMAT_CSUM_STRIDX : MLX5_CQE_FORMAT_CSUM);
+ MLX5_SET(cqc, cqc, cqe_compression_layout,
+ MLX5_CAP_GEN(mdev, enhanced_cqe_compression) ?
+ MLX5_CQE_COMPRESS_LAYOUT_ENHANCED :
+ MLX5_CQE_COMPRESS_LAYOUT_BASIC);
MLX5_SET(cqc, cqc, cqe_comp_en, 1);
}
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 1669c7d7f285..c462b76743b6 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -1205,6 +1205,13 @@ int mlx5e_open_rq(struct mlx5e_params *params, struct mlx5e_rq_param *param,
MLX5_CAP_GEN(mdev, mini_cqe_resp_stride_index))
__set_bit(MLX5E_RQ_STATE_MINI_CQE_HW_STRIDX, &rq->state);
+ /* For enhanced CQE compression packet processing. decompress
+ * session according to the enhanced layout.
+ */
+ if (MLX5E_GET_PFLAG(params, MLX5E_PFLAG_RX_CQE_COMPRESS) &&
+ MLX5_CAP_GEN(mdev, enhanced_cqe_compression))
+ __set_bit(MLX5E_RQ_STATE_MINI_CQE_ENHANCED, &rq->state);
+
return 0;
err_destroy_rq:
@@ -1895,6 +1902,7 @@ static int mlx5e_alloc_cq_common(struct mlx5e_priv *priv,
struct mlx5_cqe64 *cqe = mlx5_cqwq_get_wqe(&cq->wq, i);
cqe->op_own = 0xf1;
+ cqe->validity_iteration_count = 0xff;
}
cq->mdev = mdev;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index a61a43fc8d5c..b1ea0b995d9c 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -89,6 +89,25 @@ static inline void mlx5e_read_cqe_slot(struct mlx5_cqwq *wq,
memcpy(data, mlx5_cqwq_get_wqe(wq, ci), sizeof(struct mlx5_cqe64));
}
+static void mlx5e_read_enhanced_title_slot(struct mlx5e_rq *rq,
+ struct mlx5_cqe64 *cqe)
+{
+ struct mlx5e_cq_decomp *cqd = &rq->cqd;
+ struct mlx5_cqe64 *title = &cqd->title;
+
+ memcpy(title, cqe, sizeof(struct mlx5_cqe64));
+
+ if (likely(test_bit(MLX5E_RQ_STATE_MINI_CQE_HW_STRIDX, &rq->state)))
+ return;
+
+ if (rq->wq_type == MLX5_WQ_TYPE_LINKED_LIST_STRIDING_RQ)
+ cqd->wqe_counter = mpwrq_get_cqe_stride_index(title) +
+ mpwrq_get_cqe_consumed_strides(title);
+ else
+ cqd->wqe_counter =
+ mlx5_wq_cyc_ctr2ix(&rq->wqe.wq, be16_to_cpu(title->wqe_counter) + 1);
+}
+
static inline void mlx5e_read_title_slot(struct mlx5e_rq *rq,
struct mlx5_cqwq *wq,
u32 cqcc)
@@ -175,6 +194,38 @@ static inline void mlx5e_decompress_cqe_no_hash(struct mlx5e_rq *rq,
cqd->title.rss_hash_result = 0;
}
+static u32 mlx5e_decompress_enhanced_cqe(struct mlx5e_rq *rq,
+ struct mlx5_cqwq *wq,
+ struct mlx5_cqe64 *cqe,
+ int budget_rem)
+{
+ struct mlx5e_cq_decomp *cqd = &rq->cqd;
+ u32 cqcc, left;
+ u32 i;
+
+ left = get_cqe_enhanced_num_mini_cqes(cqe);
+ /* Here we avoid breaking the cqe compression session in the middle
+ * in case budget is not sufficient to handle all of it. In this case
+ * we return work_done == budget_rem to give 'busy' napi indication.
+ */
+ if (unlikely(left > budget_rem))
+ return budget_rem;
+
+ cqcc = wq->cc;
+ cqd->mini_arr_idx = 0;
+ memcpy(cqd->mini_arr, cqe, sizeof(struct mlx5_cqe64));
+ for (i = 0; i < left; i++, cqd->mini_arr_idx++, cqcc++) {
+ mlx5e_decompress_cqe_no_hash(rq, wq, cqcc);
+ INDIRECT_CALL_3(rq->handle_rx_cqe, mlx5e_handle_rx_cqe_mpwrq,
+ mlx5e_handle_rx_cqe, mlx5e_handle_rx_cqe_mpwrq_shampo,
+ rq, &cqd->title);
+ }
+ wq->cc = cqcc;
+ rq->stats->cqe_compress_pkts += left;
+
+ return left;
+}
+
static inline u32 mlx5e_decompress_cqes_cont(struct mlx5e_rq *rq,
struct mlx5_cqwq *wq,
int update_owner_only,
@@ -220,7 +271,7 @@ static inline u32 mlx5e_decompress_cqes_start(struct mlx5e_rq *rq,
rq, &cqd->title);
cqd->mini_arr_idx++;
- return mlx5e_decompress_cqes_cont(rq, wq, 1, budget_rem) - 1;
+ return mlx5e_decompress_cqes_cont(rq, wq, 1, budget_rem);
}
static inline bool mlx5e_rx_cache_put(struct mlx5e_rq *rq, struct page *page)
@@ -2211,45 +2262,102 @@ static void mlx5e_handle_rx_cqe_mpwrq(struct mlx5e_rq *rq, struct mlx5_cqe64 *cq
mlx5_wq_ll_pop(wq, cqe->wqe_id, &wqe->next.next_wqe_index);
}
-int mlx5e_poll_rx_cq(struct mlx5e_cq *cq, int budget)
+static int mlx5e_rx_cq_process_enhanced_cqe_comp(struct mlx5e_rq *rq,
+ struct mlx5_cqwq *cqwq,
+ int budget_rem)
{
- struct mlx5e_rq *rq = container_of(cq, struct mlx5e_rq, cq);
- struct mlx5_cqwq *cqwq = &cq->wq;
- struct mlx5_cqe64 *cqe;
+ struct mlx5_cqe64 *cqe, *title_cqe = NULL;
+ struct mlx5e_cq_decomp *cqd = &rq->cqd;
int work_done = 0;
- if (unlikely(!test_bit(MLX5E_RQ_STATE_ENABLED, &rq->state)))
- return 0;
+ cqe = mlx5_cqwq_get_cqe_enahnced_comp(cqwq);
+ if (!cqe)
+ return work_done;
- if (rq->cqd.left) {
- work_done += mlx5e_decompress_cqes_cont(rq, cqwq, 0, budget);
- if (work_done >= budget)
- goto out;
+ if (cqd->last_cqe_title &&
+ (mlx5_get_cqe_format(cqe) == MLX5_COMPRESSED)) {
+ rq->stats->cqe_compress_blks++;
+ cqd->last_cqe_title = false;
}
- cqe = mlx5_cqwq_get_cqe(cqwq);
- if (!cqe) {
- if (unlikely(work_done))
- goto out;
- return 0;
+ do {
+ if (mlx5_get_cqe_format(cqe) == MLX5_COMPRESSED) {
+ if (title_cqe) {
+ mlx5e_read_enhanced_title_slot(rq, title_cqe);
+ title_cqe = NULL;
+ rq->stats->cqe_compress_blks++;
+ }
+ work_done +=
+ mlx5e_decompress_enhanced_cqe(rq, cqwq, cqe,
+ budget_rem - work_done);
+ continue;
+ }
+ title_cqe = cqe;
+ mlx5_cqwq_pop(cqwq);
+
+ INDIRECT_CALL_3(rq->handle_rx_cqe, mlx5e_handle_rx_cqe_mpwrq,
+ mlx5e_handle_rx_cqe, mlx5e_handle_rx_cqe_mpwrq_shampo,
+ rq, cqe);
+ work_done++;
+ } while (work_done < budget_rem &&
+ (cqe = mlx5_cqwq_get_cqe_enahnced_comp(cqwq)));
+
+ /* last cqe might be title on next poll bulk */
+ if (title_cqe) {
+ mlx5e_read_enhanced_title_slot(rq, title_cqe);
+ cqd->last_cqe_title = true;
}
- do {
+ return work_done;
+}
+
+static int mlx5e_rx_cq_process_basic_cqe_comp(struct mlx5e_rq *rq,
+ struct mlx5_cqwq *cqwq,
+ int budget_rem)
+{
+ struct mlx5_cqe64 *cqe;
+ int work_done = 0;
+
+ if (rq->cqd.left)
+ work_done += mlx5e_decompress_cqes_cont(rq, cqwq, 0, budget_rem);
+
+ while (work_done < budget_rem && (cqe = mlx5_cqwq_get_cqe(cqwq))) {
if (mlx5_get_cqe_format(cqe) == MLX5_COMPRESSED) {
work_done +=
mlx5e_decompress_cqes_start(rq, cqwq,
- budget - work_done);
+ budget_rem - work_done);
continue;
}
mlx5_cqwq_pop(cqwq);
-
INDIRECT_CALL_3(rq->handle_rx_cqe, mlx5e_handle_rx_cqe_mpwrq,
mlx5e_handle_rx_cqe, mlx5e_handle_rx_cqe_mpwrq_shampo,
rq, cqe);
- } while ((++work_done < budget) && (cqe = mlx5_cqwq_get_cqe(cqwq)));
+ work_done++;
+ }
+
+ return work_done;
+}
+
+int mlx5e_poll_rx_cq(struct mlx5e_cq *cq, int budget)
+{
+ struct mlx5e_rq *rq = container_of(cq, struct mlx5e_rq, cq);
+ struct mlx5_cqwq *cqwq = &cq->wq;
+ int work_done;
+
+ if (unlikely(!test_bit(MLX5E_RQ_STATE_ENABLED, &rq->state)))
+ return 0;
+
+ if (test_bit(MLX5E_RQ_STATE_MINI_CQE_ENHANCED, &rq->state))
+ work_done = mlx5e_rx_cq_process_enhanced_cqe_comp(rq, cqwq,
+ budget);
+ else
+ work_done = mlx5e_rx_cq_process_basic_cqe_comp(rq, cqwq,
+ budget);
+
+ if (work_done == 0)
+ return 0;
-out:
if (test_bit(MLX5E_RQ_STATE_SHAMPO, &rq->state) && rq->hw_gro_data->skb)
mlx5e_shampo_flush_skb(rq, NULL, false);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/wq.h b/drivers/net/ethernet/mellanox/mlx5/core/wq.h
index 4d629e5ddbc7..e4ef1d24a3ad 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/wq.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/wq.h
@@ -243,6 +243,23 @@ static inline struct mlx5_cqe64 *mlx5_cqwq_get_cqe(struct mlx5_cqwq *wq)
return cqe;
}
+static inline
+struct mlx5_cqe64 *mlx5_cqwq_get_cqe_enahnced_comp(struct mlx5_cqwq *wq)
+{
+ u8 sw_validity_iteration_count = mlx5_cqwq_get_wrap_cnt(wq) & 0xff;
+ u32 ci = mlx5_cqwq_get_ci(wq);
+ struct mlx5_cqe64 *cqe;
+
+ cqe = mlx5_cqwq_get_wqe(wq, ci);
+ if (cqe->validity_iteration_count != sw_validity_iteration_count)
+ return NULL;
+
+ /* ensure cqe content is read after cqe ownership bit/validity byte */
+ dma_rmb();
+
+ return cqe;
+}
+
static inline u32 mlx5_wq_ll_get_size(struct mlx5_wq_ll *wq)
{
return (u32)wq->fbc.sz_m1 + 1;
diff --git a/include/linux/mlx5/device.h b/include/linux/mlx5/device.h
index 1ff91cb79ded..eb3fac30488b 100644
--- a/include/linux/mlx5/device.h
+++ b/include/linux/mlx5/device.h
@@ -882,6 +882,12 @@ static inline u8 get_cqe_opcode(struct mlx5_cqe64 *cqe)
return cqe->op_own >> 4;
}
+static inline u8 get_cqe_enhanced_num_mini_cqes(struct mlx5_cqe64 *cqe)
+{
+ /* num_of_mini_cqes is zero based */
+ return get_cqe_opcode(cqe) + 1;
+}
+
static inline u8 get_cqe_lro_tcppsh(struct mlx5_cqe64 *cqe)
{
return (cqe->lro.tcppsh_abort_dupack >> 6) & 1;
--
2.38.1
Powered by blists - more mailing lists