[PATCH net-next v4 13/13] net: mana: keep the existing queues when the channel count is raised
From: Long Li <longli@microsoft.com>
Date: 2026-09-08 03:29:31
Also in:
linux-hyperv, linux-rdma, lkml
Subsystem:
hyper-v/azure core and drivers, networking drivers, networking [general], the rest · Maintainers:
"K. Y. Srinivasan", Haiyang Zhang, Wei Liu, Dexuan Cui, Long Li, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Keep existing queues and allocate only the added tail. Growing N to M now needs M SQ/RQ pairs at peak, rather than N + M. Track the fresh queues separately for failure cleanup and XDP references. Wait for TX-selection readers before freeing old containers, and clear slots during partial teardown. Full rebuilds now keep the current count. Advertise in-driver resize recovery after converting the live resize paths. Failed rollback still requires recovery. Signed-off-by: Long Li <longli@microsoft.com> --- Changes in v4: - Wait for TX-selection readers before freeing old containers. - Clear TX pointer-array slots after partial teardown. - Shorten comments and qualify the resize-recovery description. .../net/ethernet/microsoft/mana/mana_bpf.c | 2 +- drivers/net/ethernet/microsoft/mana/mana_en.c | 209 +++++++++++++++--- .../ethernet/microsoft/mana/mana_ethtool.c | 31 ++- include/net/mana/gdma.h | 8 +- include/net/mana/mana.h | 7 +- 5 files changed, 217 insertions(+), 40 deletions(-)
diff --git a/drivers/net/ethernet/microsoft/mana/mana_bpf.c b/drivers/net/ethernet/microsoft/mana/mana_bpf.c
index 8daeb65cc647bb4cf4391f6fadcd04793630c3b6..fc7bb0016d5dd8e112c544baa83b3efafb6eeb5c 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_bpf.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_bpf.c@@ -206,7 +206,7 @@ static int mana_xdp_set(struct net_device *ndev, struct bpf_prog *prog, return -ENOMEM; } - err = mana_alloc_qset(apc, scratch, apc->num_queues, + err = mana_alloc_qset(apc, scratch, apc->rx_queue_size, apc->tx_queue_size, apc->priv_flags, apc->configured_mtu, prog, &newq);
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index 158f9a6ce42157ad7afd45ec642405fbd81f0bac..29f54f91cb0094f65cdd09d82cf4f29f3d296437 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c@@ -927,7 +927,7 @@ static int mana_change_mtu(struct net_device *ndev, int new_mtu) if (!scratch) return -ENOMEM; - err = mana_alloc_qset(mpc, scratch, mpc->num_queues, mpc->rx_queue_size, + err = mana_alloc_qset(mpc, scratch, mpc->rx_queue_size, mpc->tx_queue_size, mpc->priv_flags, new_mtu, mpc->bpf_prog, &newq); if (err)
@@ -2878,7 +2878,9 @@ static void mana_deinit_txq(struct mana_port_context *apc, struct mana_txq *txq) mana_gd_destroy_queue(gd->gdma_context, txq->gdma_sq); } -static void mana_destroy_txq(struct mana_port_context *apc) +/* Keep the array and queues below @first; clear freed slots. */ +static void mana_destroy_txq_from(struct mana_port_context *apc, + unsigned int first) { struct napi_struct *napi; int i;
@@ -2886,7 +2888,7 @@ static void mana_destroy_txq(struct mana_port_context *apc) if (!apc->tx_qp) return; - for (i = 0; i < apc->num_queues; i++) { + for (i = first; i < apc->num_queues; i++) { if (!apc->tx_qp[i]) continue;
@@ -2910,7 +2912,16 @@ static void mana_destroy_txq(struct mana_port_context *apc) mana_deinit_txq(apc, &apc->tx_qp[i]->txq); kvfree(apc->tx_qp[i]); + apc->tx_qp[i] = NULL; } +} + +static void mana_destroy_txq(struct mana_port_context *apc) +{ + if (!apc->tx_qp) + return; + + mana_destroy_txq_from(apc, 0); kfree(apc->tx_qp); apc->tx_qp = NULL;
@@ -2941,8 +2952,11 @@ static void mana_create_txq_debugfs(struct mana_port_context *apc, int idx) tx_qp->tx_cq.gdma_cq, &mana_dbg_q_fops); } +/* With @first nonzero, use the existing array and unwind only new queues on + * failure. + */ static int mana_create_txq(struct mana_port_context *apc, - struct net_device *net) + struct net_device *net, unsigned int first) { struct mana_context *ac = apc->ac; struct gdma_dev *gd = ac->gdma_dev;
@@ -2957,9 +2971,14 @@ static int mana_create_txq(struct mana_port_context *apc, int err; int i; - apc->tx_qp = kzalloc_objs(struct mana_tx_qp *, apc->num_queues); - if (!apc->tx_qp) - return -ENOMEM; + if (first) { + if (WARN_ON(!apc->tx_qp)) + return -EINVAL; + } else { + apc->tx_qp = kzalloc_objs(struct mana_tx_qp *, apc->num_queues); + if (!apc->tx_qp) + return -ENOMEM; + } /* The minimum size of the WQE is 32 bytes, hence * apc->tx_queue_size represents the maximum number of WQEs
@@ -2976,7 +2995,7 @@ static int mana_create_txq(struct mana_port_context *apc, gc = gd->gdma_context; - for (i = 0; i < apc->num_queues; i++) { + for (i = first; i < apc->num_queues; i++) { apc->tx_qp[i] = kvzalloc_obj(*apc->tx_qp[i]); if (!apc->tx_qp[i]) { err = -ENOMEM;
@@ -3084,7 +3103,10 @@ static int mana_create_txq(struct mana_port_context *apc, out: netdev_err(net, "Failed to create %d TX queues, %d\n", apc->num_queues, err); - mana_destroy_txq(apc); + if (first) + mana_destroy_txq_from(apc, first); + else + mana_destroy_txq(apc); return err; }
@@ -3440,14 +3462,15 @@ static void mana_create_rxq_debugfs(struct mana_port_context *apc, int idx) &mana_dbg_q_fops); } +/* The caller must destroy queues added before a failure. */ static int mana_add_rx_queues(struct mana_port_context *apc, - struct net_device *ndev) + struct net_device *ndev, unsigned int first) { struct mana_rxq *rxq; int err = 0; int i; - for (i = 0; i < apc->num_queues; i++) { + for (i = first; i < apc->num_queues; i++) { rxq = mana_create_rxq(apc, i, &apc->eqs[i], ndev); if (IS_ERR(rxq)) { err = PTR_ERR(rxq);
@@ -3465,14 +3488,15 @@ static int mana_add_rx_queues(struct mana_port_context *apc, return err; } -static void mana_destroy_rxqs(struct mana_port_context *apc) +static void mana_destroy_rxqs_from(struct mana_port_context *apc, + unsigned int first) { struct mana_rxq *rxq; u32 rxq_idx; if (apc->rxqs) { - for (rxq_idx = 0; rxq_idx < apc->num_queues; rxq_idx++) { + for (rxq_idx = first; rxq_idx < apc->num_queues; rxq_idx++) { rxq = apc->rxqs[rxq_idx]; if (!rxq) continue;
@@ -3483,6 +3507,11 @@ static void mana_destroy_rxqs(struct mana_port_context *apc) } } +static void mana_destroy_rxqs(struct mana_port_context *apc) +{ + mana_destroy_rxqs_from(apc, 0); +} + static void mana_destroy_vport(struct mana_port_context *apc) { struct gdma_dev *gd = apc->ac->gdma_dev;
@@ -3856,7 +3885,7 @@ int mana_alloc_queues(struct net_device *ndev) goto destroy_vport; } - err = mana_create_txq(apc, ndev); + err = mana_create_txq(apc, ndev, 0); if (err) { netdev_err(ndev, "Failed to create TXQ on vPort %u: %d\n", apc->port_idx, err);
@@ -3871,7 +3900,7 @@ int mana_alloc_queues(struct net_device *ndev) goto destroy_txq; } - err = mana_add_rx_queues(apc, ndev); + err = mana_add_rx_queues(apc, ndev, 0); if (err) goto destroy_rxq;
@@ -4254,8 +4283,137 @@ void mana_discard_split(struct mana_qset *newq, struct mana_qset *tailq) memset(tailq, 0, sizeof(*tailq)); } +/* Carry existing queues into @out_new; allocate only the tail. @out_fresh + * isolates new queues for cleanup after a failed publish. + */ +int mana_grow_qset(struct mana_port_context *apc, + struct mana_port_context *scratch, unsigned int new_count, + struct mana_qset *out_new, struct mana_qset *out_fresh) +{ + unsigned int old_count = apc->num_queues; + struct mana_tx_qp **new_tx, **fresh_tx; + struct mana_rxq **new_rx, **fresh_rx; + struct net_device *ndev = apc->ndev; + unsigned int fresh_count; + bool indir_lost; + unsigned int i; + int err; + + ASSERT_RTNL(); + + if (WARN_ON(new_count <= old_count)) + return -EINVAL; + if (WARN_ON(!apc->tx_qp || !apc->rxqs)) + return -EINVAL; + + fresh_count = new_count - old_count; + + new_tx = kzalloc_objs(struct mana_tx_qp *, new_count); + new_rx = kzalloc_objs(struct mana_rxq *, new_count); + fresh_tx = kzalloc_objs(struct mana_tx_qp *, fresh_count); + fresh_rx = kzalloc_objs(struct mana_rxq *, fresh_count); + if (!new_tx || !new_rx || !fresh_tx || !fresh_rx) { + err = -ENOMEM; + goto free_arrays; + } + + for (i = 0; i < old_count; i++) { + new_tx[i] = apc->tx_qp[i]; + new_rx[i] = apc->rxqs[i]; + } + + scratch->num_queues = new_count; + scratch->tx_qp = new_tx; + scratch->rxqs = new_rx; + + err = mana_rss_table_alloc(scratch); + if (err) + goto free_arrays; + + err = mana_grow_eqs(apc, new_count); + if (err) + goto cleanup_rss; + + scratch->eqs = apc->eqs; + scratch->num_eqs = apc->num_eqs; + + err = mana_create_txq(scratch, ndev, old_count); + if (err) + goto cleanup_rss; + + err = mana_add_rx_queues(scratch, ndev, old_count); + if (err) + goto cleanup_rxq; + + if (mana_rss_table_keep(apc, new_count, &indir_lost)) + memcpy(scratch->indir_table, apc->indir_table, + apc->indir_table_sz * sizeof(*apc->indir_table)); + else + mana_rss_table_init(scratch); + + mana_qset_snapshot(scratch, out_new); + out_new->rxfh_indir_lost = indir_lost; + + for (i = 0; i < fresh_count; i++) { + fresh_tx[i] = new_tx[old_count + i]; + fresh_rx[i] = new_rx[old_count + i]; + } + + memset(out_fresh, 0, sizeof(*out_fresh)); + out_fresh->tx_qp = fresh_tx; + out_fresh->rxqs = fresh_rx; + out_fresh->default_rxobj = INVALID_MANA_HANDLE; + out_fresh->num_queues = fresh_count; + out_fresh->rx_queue_size = apc->rx_queue_size; + out_fresh->tx_queue_size = apc->tx_queue_size; + out_fresh->priv_flags = apc->priv_flags; + out_fresh->mtu = apc->configured_mtu; + out_fresh->bpf_prog = apc->bpf_prog; + + /* Take XDP refs on fresh RXQs only. On the merged set, + * mana_chn_setxdp() returns early on the carried rxqs[0]. + */ + mana_qset_install(scratch, out_fresh); + mana_chn_setxdp(scratch, mana_xdp_get(apc)); + + return 0; + +cleanup_rxq: + mana_destroy_rxqs_from(scratch, old_count); + mana_destroy_txq_from(scratch, old_count); +cleanup_rss: + mana_cleanup_indir_table(scratch); +free_arrays: + /* Free containers only; carried queues remain live. */ + scratch->tx_qp = NULL; + scratch->rxqs = NULL; + kfree(new_tx); + kfree(new_rx); + kfree(fresh_tx); + kfree(fresh_rx); + + mana_shrink_eqs(apc, apc->num_queues); + + netdev_err(ndev, "%s(num_queues=%u) failed: %d\n", __func__, + new_count, err); + return err; +} + +/* Free merged containers only, not carried queues. The caller must retire fresh + * queues separately. + */ +void mana_discard_grow(struct mana_qset *newq) +{ + kfree(newq->tx_qp); + kfree(newq->rxqs); + kfree(newq->indir_table); + kfree(newq->rxobj_table); + memset(newq, 0, sizeof(*newq)); +} + +/* Rebuild at the current count; resize uses split/grow. */ int mana_alloc_qset(struct mana_port_context *apc, - struct mana_port_context *scratch, unsigned int num_queues, + struct mana_port_context *scratch, unsigned int rx_queue_size, unsigned int tx_queue_size, u32 priv_flags, int mtu, struct bpf_prog *bpf_prog, struct mana_qset *out)
@@ -4266,7 +4424,7 @@ int mana_alloc_qset(struct mana_port_context *apc, ASSERT_RTNL(); - scratch->num_queues = num_queues; + scratch->num_queues = apc->num_queues; scratch->rx_queue_size = rx_queue_size; scratch->tx_queue_size = tx_queue_size; scratch->priv_flags = priv_flags;
@@ -4282,22 +4440,19 @@ int mana_alloc_qset(struct mana_port_context *apc, if (err) goto cleanup_rxq_array; - err = mana_grow_eqs(apc, num_queues); - if (err) - goto cleanup_rss; - + /* Reuse the existing EQ pool; the queue count is unchanged. */ scratch->eqs = apc->eqs; scratch->num_eqs = apc->num_eqs; - err = mana_create_txq(scratch, ndev); + err = mana_create_txq(scratch, ndev, 0); if (err) goto cleanup_rss; - err = mana_add_rx_queues(scratch, ndev); + err = mana_add_rx_queues(scratch, ndev, 0); if (err) goto cleanup_rxq; - if (mana_rss_table_keep(apc, num_queues, &indir_lost)) + if (mana_rss_table_keep(apc, scratch->num_queues, &indir_lost)) memcpy(scratch->indir_table, apc->indir_table, apc->indir_table_sz * sizeof(*apc->indir_table)); else
@@ -4316,10 +4471,8 @@ int mana_alloc_qset(struct mana_port_context *apc, kfree(scratch->rxqs); scratch->rxqs = NULL; out_err: - mana_shrink_eqs(apc, apc->num_queues); - netdev_err(ndev, "%s(num_queues=%u) failed: %d\n", __func__, - num_queues, err); + apc->num_queues, err); return err; }
@@ -4531,7 +4684,7 @@ int mana_publish_qset(struct mana_port_context *apc, struct mana_qset *newq, } /* Create missing debugfs nodes once retiring names are gone. */ -static void mana_qset_debugfs_publish(struct mana_port_context *apc) +void mana_qset_debugfs_publish(struct mana_port_context *apc) { unsigned int i;
diff --git a/drivers/net/ethernet/microsoft/mana/mana_ethtool.c b/drivers/net/ethernet/microsoft/mana/mana_ethtool.c
index 0b8c2f61d6263c65a8119b94426f794b218ad55f..6586a9d2a13438bd85d0aa55c55c08a0b3301f78 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_ethtool.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_ethtool.c@@ -684,7 +684,7 @@ static int mana_set_channels(struct net_device *ndev, struct mana_port_context *apc = netdev_priv(ndev); unsigned int new_count = channels->combined_count; struct mana_port_context *scratch; - struct mana_qset newq, oldq; + struct mana_qset newq, oldq, freshq; int err; if (new_count < 1 || new_count > apc->max_queues) {
@@ -767,19 +767,33 @@ static int mana_set_channels(struct net_device *ndev, goto free_scratch; } - err = mana_alloc_qset(apc, scratch, new_count, apc->rx_queue_size, - apc->tx_queue_size, apc->priv_flags, - apc->configured_mtu, apc->bpf_prog, &newq); + err = mana_grow_qset(apc, scratch, new_count, &newq, &freshq); if (err) goto free_scratch; err = mana_publish_qset(apc, &newq, &oldq); if (err) { - mana_free_qset(scratch, &newq); + /* Free only the new queues, then discard the merged containers. + */ + mana_free_qset(scratch, &freshq); + mana_discard_grow(&newq); goto free_scratch; } - mana_free_qset(scratch, &oldq); + /* Wait for ndo_select_queue() readers of oldq.indir_table. All queues + * are now live in newq; free only the old and fresh containers. + */ + synchronize_net(); + + kfree(oldq.tx_qp); + kfree(oldq.rxqs); + kfree(oldq.indir_table); + kfree(oldq.rxobj_table); + kfree(freshq.tx_qp); + kfree(freshq.rxqs); + + /* No retirement runs to publish the new queues' debugfs nodes. */ + mana_qset_debugfs_publish(apc); free_scratch: mana_publish_close_if_needed(apc);
@@ -856,7 +870,7 @@ static int mana_set_ringparam(struct net_device *ndev, goto clear_flag; } - err = mana_alloc_qset(apc, scratch, apc->num_queues, new_rx, new_tx, + err = mana_alloc_qset(apc, scratch, new_rx, new_tx, apc->priv_flags, apc->configured_mtu, apc->bpf_prog, &newq); if (err) {
@@ -876,7 +890,6 @@ static int mana_set_ringparam(struct net_device *ndev, mana_free_qset(scratch, &oldq); free_scratch: - /* Release unpublished queues before closing their shared EQ pool. */ mana_publish_close_if_needed(apc); mana_qset_scratch_free(scratch); clear_flag:
@@ -946,7 +959,7 @@ static int mana_set_priv_flags(struct net_device *ndev, u32 priv_flags) goto clear_flag; } - err = mana_alloc_qset(apc, scratch, apc->num_queues, apc->rx_queue_size, + err = mana_alloc_qset(apc, scratch, apc->rx_queue_size, apc->tx_queue_size, priv_flags, apc->configured_mtu, apc->bpf_prog, &newq); if (err)
diff --git a/include/net/mana/gdma.h b/include/net/mana/gdma.h
index 308950f9b54b0485bac66b80d63e257eaf5f787e..666565ffb26aad6b77044ce1604568aa208a5b79 100644
--- a/include/net/mana/gdma.h
+++ b/include/net/mana/gdma.h@@ -686,6 +686,11 @@ enum { /* Driver supports non-contiguous queue buffers */ #define GDMA_DRV_CAP_FLAG_1_NON_CONTIGUOUS_BUFFERS BIT(30) +/* Resize failures are handled in-driver; a failed rollback still needs + * recovery. + */ +#define GDMA_DRV_CAP_FLAG_1_SELF_RECOVERY_ON_QUEUE_RESIZE_FAILURE BIT(31) + #define GDMA_DRV_CAP_FLAGS1 \ (GDMA_DRV_CAP_FLAG_1_EQ_SHARING_MULTI_VPORT | \ GDMA_DRV_CAP_FLAG_1_NAPI_WKDONE_FIX | \
@@ -703,7 +708,8 @@ enum { GDMA_DRV_CAP_FLAG_1_HWC_TIMEOUT_RECOVERY | \ GDMA_DRV_CAP_FLAG_1_EQ_MSI_UNSHARE_MULTI_VPORT | \ GDMA_DRV_CAP_FLAG_1_DYN_INTERRUPT_MODERATION | \ - GDMA_DRV_CAP_FLAG_1_NON_CONTIGUOUS_BUFFERS) + GDMA_DRV_CAP_FLAG_1_NON_CONTIGUOUS_BUFFERS | \ + GDMA_DRV_CAP_FLAG_1_SELF_RECOVERY_ON_QUEUE_RESIZE_FAILURE) #define GDMA_DRV_CAP_FLAGS2 0
diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h
index 5ec75de0b644569acdf697e997c262d999295a06..cc936ae97a0318620c011ae55925595858e0fc3d 100644
--- a/include/net/mana/mana.h
+++ b/include/net/mana/mana.h@@ -739,7 +739,7 @@ static inline struct mana_stats_rx *mana_rxq_stats(struct mana_rxq *rxq) } int mana_alloc_qset(struct mana_port_context *apc, - struct mana_port_context *scratch, unsigned int num_queues, + struct mana_port_context *scratch, unsigned int rx_queue_size, unsigned int tx_queue_size, u32 priv_flags, int mtu, struct bpf_prog *bpf_prog, struct mana_qset *out);
@@ -747,10 +747,15 @@ int mana_split_qset(struct mana_port_context *apc, struct mana_port_context *scratch, unsigned int new_count, struct mana_qset *out_new, struct mana_qset *out_tail); void mana_discard_split(struct mana_qset *newq, struct mana_qset *tailq); +int mana_grow_qset(struct mana_port_context *apc, + struct mana_port_context *scratch, unsigned int new_count, + struct mana_qset *out_new, struct mana_qset *out_fresh); +void mana_discard_grow(struct mana_qset *newq); int mana_publish_qset(struct mana_port_context *apc, struct mana_qset *newq, struct mana_qset *out_old); void mana_publish_close_if_needed(struct mana_port_context *apc); void mana_free_qset(struct mana_port_context *scratch, struct mana_qset *qset); +void mana_qset_debugfs_publish(struct mana_port_context *apc); void mana_dim_change(struct mana_cq *cq, bool enable);
--
2.43.0