Attaching or detaching an XDP program changes the RX buffer layout - full pages with headroom rather than page fragments, see mana_get_rxbuf_cfg() - so it rebuilds the queues. Convert mana_xdp_set() to the pre-allocate and swap helpers, completing the removal of detach/attach from the reconfiguration paths.
struct mana_qset gains bpf_prog, so the program the queues were built for is swapped atomically with them and restored by the rollback path. Refcounting is handled by the swap helpers. mana_publish_qset() already re-attaches apc->bpf_prog to the new RX queues, which are created with bpf_prog == NULL; installing qset->bpf_prog first means that same call now attaches the new program. mana_free_qset() drops the old set's per-queue references. The caller's reference is still consumed by the port context and the old one released once, as before. mana_pre_alloc_rxbufs() is no longer needed here. The TX timeout reset handler is now its only caller. Signed-off-by: Long Li <[email protected]> --- .../net/ethernet/microsoft/mana/mana_bpf.c | 75 +++++++++++-------- drivers/net/ethernet/microsoft/mana/mana_en.c | 15 ++-- .../ethernet/microsoft/mana/mana_ethtool.c | 7 +- include/net/mana/mana.h | 16 ++-- 4 files changed, 65 insertions(+), 48 deletions(-) diff --git a/drivers/net/ethernet/microsoft/mana/mana_bpf.c b/drivers/net/ethernet/microsoft/mana/mana_bpf.c index e16ce2a0715839594a5837288c1d4c1de412e7fb..1a6a490a84f2e5b4c9895645ff6f40beb55f497c 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_bpf.c +++ b/drivers/net/ethernet/microsoft/mana/mana_bpf.c @@ -175,10 +175,24 @@ void mana_chn_setxdp(struct mana_port_context *apc, struct bpf_prog *prog) bpf_prog_put(old_prog); } +/* mana_xdp_set - attach or detach an XDP program + * + * Attaching or detaching XDP changes the RX buffer layout (full pages with + * headroom vs. page fragments), so the RX queues must be rebuilt. Uses the + * pre-allocate + swap path: the new set is built for @prog while the + * current one keeps serving traffic. On allocation failure nothing changes + * and the error is returned to the caller. + * + * mana_publish_qset() installs qset->bpf_prog onto apc and re-attaches it + * to the new RX queues, and mana_free_qset() drops the old set's per-queue + * references, so refcounting is handled by the swap helpers. + */ static int mana_xdp_set(struct net_device *ndev, struct bpf_prog *prog, struct netlink_ext_ack *extack) { struct mana_port_context *apc = netdev_priv(ndev); + struct mana_port_context *scratch; + struct mana_qset newq, oldq; struct bpf_prog *old_prog; struct gdma_context *gc; int err; @@ -198,46 +212,46 @@ static int mana_xdp_set(struct net_device *ndev, struct bpf_prog *prog, return -EOPNOTSUPP; } - /* One refcnt of the prog is hold by the caller already, so - * don't increase refcnt for this one. - */ - apc->bpf_prog = prog; - if (apc->port_is_up) { - /* Re-create rxq's after xdp prog was loaded or unloaded. - * Ex: re create rxq's to switch from full pages to smaller - * size page fragments when xdp prog is unloaded and - * vice-versa. - */ - - /* Pre-allocate buffers to prevent failure in mana_attach */ - err = mana_pre_alloc_rxbufs(apc, ndev->mtu, apc->num_queues); - if (err) { + scratch = mana_qset_scratch_alloc(apc); + if (!scratch) { NL_SET_ERR_MSG_MOD(extack, - "XDP: Insufficient memory for tx/rx re-config"); - return err; + "XDP: Insufficient memory for re-config"); + return -ENOMEM; } - err = mana_detach(ndev, false); + err = mana_alloc_qset(scratch, apc->num_queues, + apc->rx_queue_size, apc->tx_queue_size, + apc->priv_flags, apc->configured_mtu, + prog, &newq); if (err) { - netdev_err(ndev, - "mana_detach failed at xdp set: %d\n", err); NL_SET_ERR_MSG_MOD(extack, - "XDP: Re-config failed at detach"); - goto err_dealloc_rxbuffs; + "XDP: Re-config failed at alloc"); + mana_qset_scratch_free(scratch); + return err; } - err = mana_attach(ndev); + err = mana_publish_qset(apc, &newq, &oldq); if (err) { - netdev_err(ndev, - "mana_attach failed at xdp set: %d\n", err); NL_SET_ERR_MSG_MOD(extack, - "XDP: Re-config failed at attach"); - goto err_dealloc_rxbuffs; + "XDP: Re-config failed at publish"); + mana_free_qset(scratch, &newq); + /* After the cleanup above: closing destroys the EQ pool + * those queues' CQs were attached to. + */ + mana_publish_close_if_needed(apc); + mana_qset_scratch_free(scratch); + return err; } - mana_chn_setxdp(apc, prog); - mana_pre_dealloc_rxbufs(apc); + mana_free_qset(scratch, &oldq); + mana_qset_scratch_free(scratch); + } else { + /* No queues to rebuild; mana_open() will size the RX buffers + * for this program. One refcnt is held by the caller already, + * so don't take another. + */ + apc->bpf_prog = prog; } if (old_prog) @@ -250,11 +264,6 @@ static int mana_xdp_set(struct net_device *ndev, struct bpf_prog *prog, ndev->max_mtu = gc->adapter_mtu - ETH_HLEN; return 0; - -err_dealloc_rxbuffs: - apc->bpf_prog = old_prog; - mana_pre_dealloc_rxbufs(apc); - return err; } int mana_bpf(struct net_device *ndev, struct netdev_bpf *bpf) diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c index 4c79d6e82d9a93786ea877fbcef2b3f9d4093a6c..e554a776e8a941f80831047610066eed115c02b9 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_en.c +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c @@ -919,7 +919,7 @@ static int mana_change_mtu(struct net_device *ndev, int new_mtu) err = mana_alloc_qset(scratch, mpc->num_queues, mpc->rx_queue_size, mpc->tx_queue_size, mpc->priv_flags, new_mtu, - &newq); + mpc->bpf_prog, &newq); if (err) goto free_scratch; /* current qset and ndev->mtu untouched */ @@ -3986,6 +3986,7 @@ static void mana_qset_snapshot(const struct mana_port_context *ctx, out->tx_queue_size = ctx->tx_queue_size; out->priv_flags = ctx->priv_flags; out->mtu = ctx->configured_mtu; + out->bpf_prog = ctx->bpf_prog; out->mana_eqs_debugfs = ctx->mana_eqs_debugfs; } @@ -4008,6 +4009,7 @@ static void mana_qset_install(struct mana_port_context *ctx, ctx->tx_queue_size = qset->tx_queue_size; ctx->priv_flags = qset->priv_flags; ctx->configured_mtu = qset->mtu; + ctx->bpf_prog = qset->bpf_prog; ctx->mana_eqs_debugfs = qset->mana_eqs_debugfs; } @@ -4072,6 +4074,7 @@ void mana_qset_scratch_free(struct mana_port_context *scratch) * @tx_queue_size: new TX ring size * @priv_flags: new priv-flag word (affects full-page RX) * @mtu: MTU the new set is sized for + * @bpf_prog: XDP program the new set is sized for, may be NULL * @out: output qset, populated on success * * The live port context is not referenced at all, so the currently @@ -4080,7 +4083,8 @@ void mana_qset_scratch_free(struct mana_port_context *scratch) */ int mana_alloc_qset(struct mana_port_context *scratch, unsigned int num_queues, unsigned int rx_queue_size, unsigned int tx_queue_size, - u32 priv_flags, int mtu, struct mana_qset *out) + u32 priv_flags, int mtu, struct bpf_prog *bpf_prog, + struct mana_qset *out) { struct net_device *ndev = scratch->ndev; int err; @@ -4092,11 +4096,12 @@ int mana_alloc_qset(struct mana_port_context *scratch, unsigned int num_queues, scratch->tx_queue_size = tx_queue_size; scratch->priv_flags = priv_flags; - /* mana_get_rxbuf_cfg() reads this when sizing RX buffers, so the - * new set is built for the requested MTU without disturbing the - * running set. + /* mana_get_rxbuf_cfg() reads both of these when sizing RX buffers, + * so the new set is built for the requested MTU / XDP program + * without disturbing the running set. */ scratch->configured_mtu = mtu; + scratch->bpf_prog = bpf_prog; err = mana_init_port_context(scratch); if (err) diff --git a/drivers/net/ethernet/microsoft/mana/mana_ethtool.c b/drivers/net/ethernet/microsoft/mana/mana_ethtool.c index 2a6325256fad3edf1aafbc72f0cd5dc18d61384e..2cadd0f0d74e358c1b670dd6980603e0358918eb 100644 --- a/drivers/net/ethernet/microsoft/mana/mana_ethtool.c +++ b/drivers/net/ethernet/microsoft/mana/mana_ethtool.c @@ -738,7 +738,7 @@ static int mana_set_channels(struct net_device *ndev, err = mana_alloc_qset(scratch, new_count, apc->rx_queue_size, apc->tx_queue_size, apc->priv_flags, - apc->configured_mtu, &newq); + apc->configured_mtu, apc->bpf_prog, &newq); if (err) goto free_scratch; /* current qset untouched, nothing to undo */ @@ -840,7 +840,8 @@ static int mana_set_ringparam(struct net_device *ndev, } err = mana_alloc_qset(scratch, apc->num_queues, new_rx, new_tx, - apc->priv_flags, apc->configured_mtu, &newq); + apc->priv_flags, apc->configured_mtu, + apc->bpf_prog, &newq); if (err) { NL_SET_ERR_MSG_FMT(extack, "failed to change ring params: %d", err); @@ -942,7 +943,7 @@ static int mana_set_priv_flags(struct net_device *ndev, u32 priv_flags) err = mana_alloc_qset(scratch, apc->num_queues, apc->rx_queue_size, apc->tx_queue_size, priv_flags, - apc->configured_mtu, &newq); + apc->configured_mtu, apc->bpf_prog, &newq); if (err) goto free_scratch; /* current qset and priv_flags untouched */ diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h index 2fc75e6cd41a63878788182cd099379c8c698b33..bc9808f826f83df26c7af98daa181d91b7d2661d 100644 --- a/include/net/mana/mana.h +++ b/include/net/mana/mana.h @@ -590,7 +590,7 @@ struct mana_port_context { /* Indirection Table for RX & TX. The values are queue indexes */ u32 *indir_table; - u32 indir_table_sz; + u32 indir_table_sz; /* Indirection table containing RxObject Handles */ mana_handle_t *rxobj_table; @@ -720,11 +720,12 @@ struct mana_qset { unsigned int tx_queue_size; u32 priv_flags; - /* MTU the RX buffers of this set were sized for. It feeds - * mana_get_rxbuf_cfg(), so it is part of the queue-set + /* MTU and XDP program the RX buffers of this set were sized for. + * Both feed mana_get_rxbuf_cfg(), so they are part of the queue-set * configuration and must be swapped atomically with the queues. */ int mtu; + struct bpf_prog *bpf_prog; /* Per-queue-set debugfs root ("EQs"). Owned by the qset: it is * recreated by mana_create_eq() for each new set and torn down @@ -743,15 +744,16 @@ int mana_alloc_queues(struct net_device *ndev); int mana_attach(struct net_device *ndev); int mana_detach(struct net_device *ndev, bool from_close); -/* Pre-allocate + swap reconfiguration path. Allocation and teardown run - * against a scratch context so the live port context is never made to - * point at queues that are still being built or freed. +/* Pre-allocate + swap reconfiguration path (prototype). Allocation and + * teardown run against a scratch context so the live port context is only + * mutated inside mana_publish_qset(), with TX disabled. */ struct mana_port_context *mana_qset_scratch_alloc(struct mana_port_context *apc); void mana_qset_scratch_free(struct mana_port_context *scratch); int mana_alloc_qset(struct mana_port_context *scratch, unsigned int num_queues, unsigned int rx_queue_size, unsigned int tx_queue_size, - u32 priv_flags, int mtu, struct mana_qset *out); + u32 priv_flags, int mtu, struct bpf_prog *bpf_prog, + struct mana_qset *out); 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); -- 2.43.0
