Date: Thu, 24 Nov 2016 07:35:16 +0000 (UTC) From: Sepherosa Ziehau <sephe@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r309085 - head/sys/dev/hyperv/netvsc Message-ID: <201611240735.uAO7ZGJa004257@repo.freebsd.org>
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Author: sephe Date: Thu Nov 24 07:35:16 2016 New Revision: 309085 URL: https://svnweb.freebsd.org/changeset/base/309085 Log: hyperv/hn: Fix primary channel revocation Since hypervisor will not drain the TX bufring, once the channels are revoked: - Setup vmbus orphan handler properly. - Make sure that suspension will not wait the TX bufring draining forever. - GC the pending TX descs on detach path, before freeing the busdma stuffs. MFC after: 1 week Sponsored by: Microsoft Differential Revision: https://reviews.freebsd.org/D8559 Modified: head/sys/dev/hyperv/netvsc/hn_nvs.c head/sys/dev/hyperv/netvsc/if_hn.c Modified: head/sys/dev/hyperv/netvsc/hn_nvs.c ============================================================================== --- head/sys/dev/hyperv/netvsc/hn_nvs.c Thu Nov 24 06:43:11 2016 (r309084) +++ head/sys/dev/hyperv/netvsc/hn_nvs.c Thu Nov 24 07:35:16 2016 (r309085) @@ -336,8 +336,13 @@ hn_nvs_disconn_rxbuf(struct hn_softc *sc /* * Wait for the hypervisor to receive this NVS request. + * + * NOTE: + * The TX bufring will not be drained by the hypervisor, + * if the primary channel is revoked. */ - while (!vmbus_chan_tx_empty(sc->hn_prichan)) + while (!vmbus_chan_tx_empty(sc->hn_prichan) && + !vmbus_chan_is_revoked(sc->hn_prichan)) pause("waittx", 1); /* * Linger long enough for NVS to disconnect RXBUF. @@ -387,8 +392,13 @@ hn_nvs_disconn_chim(struct hn_softc *sc) /* * Wait for the hypervisor to receive this NVS request. + * + * NOTE: + * The TX bufring will not be drained by the hypervisor, + * if the primary channel is revoked. */ - while (!vmbus_chan_tx_empty(sc->hn_prichan)) + while (!vmbus_chan_tx_empty(sc->hn_prichan) && + !vmbus_chan_is_revoked(sc->hn_prichan)) pause("waittx", 1); /* * Linger long enough for NVS to disconnect chimney Modified: head/sys/dev/hyperv/netvsc/if_hn.c ============================================================================== --- head/sys/dev/hyperv/netvsc/if_hn.c Thu Nov 24 06:43:11 2016 (r309084) +++ head/sys/dev/hyperv/netvsc/if_hn.c Thu Nov 24 07:35:16 2016 (r309085) @@ -303,7 +303,8 @@ static void hn_resume(struct hn_softc static void hn_resume_data(struct hn_softc *); static void hn_resume_mgmt(struct hn_softc *); static void hn_suspend_mgmt_taskfunc(void *, int); -static void hn_chan_drain(struct vmbus_channel *); +static void hn_chan_drain(struct hn_softc *, + struct vmbus_channel *); static void hn_update_link_status(struct hn_softc *); static void hn_change_network(struct hn_softc *); @@ -327,6 +328,8 @@ static int hn_create_tx_data(struct hn static void hn_fixup_tx_data(struct hn_softc *); static void hn_destroy_tx_data(struct hn_softc *); static void hn_txdesc_dmamap_destroy(struct hn_txdesc *); +static void hn_txdesc_gc(struct hn_tx_ring *, + struct hn_txdesc *); static int hn_encap(struct ifnet *, struct hn_tx_ring *, struct hn_txdesc *, struct mbuf **); static int hn_txpkt(struct ifnet *, struct hn_tx_ring *, @@ -994,8 +997,25 @@ hn_attach(device_t dev) */ sc->hn_xact = vmbus_xact_ctx_create(bus_get_dma_tag(dev), HN_XACT_REQ_SIZE, HN_XACT_RESP_SIZE, 0); - if (sc->hn_xact == NULL) + if (sc->hn_xact == NULL) { + error = ENXIO; + goto failed; + } + + /* + * Install orphan handler for the revocation of this device's + * primary channel. + * + * NOTE: + * The processing order is critical here: + * Install the orphan handler, _before_ testing whether this + * device's primary channel has been revoked or not. + */ + vmbus_chan_set_orphan(sc->hn_prichan, sc->hn_xact); + if (vmbus_chan_is_revoked(sc->hn_prichan)) { + error = ENXIO; goto failed; + } /* * Attach the synthetic parts, i.e. NVS and RNDIS. @@ -1170,6 +1190,14 @@ hn_detach(device_t dev) struct hn_softc *sc = device_get_softc(dev); struct ifnet *ifp = sc->hn_ifp; + if (sc->hn_xact != NULL && vmbus_chan_is_revoked(sc->hn_prichan)) { + /* + * In case that the vmbus missed the orphan handler + * installation. + */ + vmbus_xact_ctx_orphan(sc->hn_xact); + } + if (device_is_attached(dev)) { HN_LOCK(sc); if (sc->hn_flags & HN_FLAG_SYNTH_ATTACHED) { @@ -1195,8 +1223,14 @@ hn_detach(device_t dev) taskqueue_free(sc->hn_tx_taskq); taskqueue_free(sc->hn_mgmt_taskq0); - if (sc->hn_xact != NULL) + if (sc->hn_xact != NULL) { + /* + * Uninstall the orphan handler _before_ the xact is + * destructed. + */ + vmbus_chan_unset_orphan(sc->hn_prichan); vmbus_xact_ctx_destroy(sc->hn_xact); + } if_free(ifp); @@ -1435,7 +1469,7 @@ hn_txdesc_hold(struct hn_txdesc *txd) { /* 0->1 transition will never work */ - KASSERT(txd->refs > 0, ("invalid refs %d", txd->refs)); + KASSERT(txd->refs > 0, ("invalid txd refs %d", txd->refs)); atomic_add_int(&txd->refs, 1); } @@ -3449,24 +3483,43 @@ hn_txdesc_dmamap_destroy(struct hn_txdes } static void +hn_txdesc_gc(struct hn_tx_ring *txr, struct hn_txdesc *txd) +{ + + KASSERT(txd->refs == 0 || txd->refs == 1, + ("invalid txd refs %d", txd->refs)); + + /* Aggregated txds will be freed by their aggregating txd. */ + if (txd->refs > 0 && (txd->flags & HN_TXD_FLAG_ONAGG) == 0) { + int freed; + + freed = hn_txdesc_put(txr, txd); + KASSERT(freed, ("can't free txdesc")); + } +} + +static void hn_tx_ring_destroy(struct hn_tx_ring *txr) { - struct hn_txdesc *txd; + int i; if (txr->hn_txdesc == NULL) return; -#ifndef HN_USE_TXDESC_BUFRING - while ((txd = SLIST_FIRST(&txr->hn_txlist)) != NULL) { - SLIST_REMOVE_HEAD(&txr->hn_txlist, link); - hn_txdesc_dmamap_destroy(txd); - } -#else - mtx_lock(&txr->hn_tx_lock); - while ((txd = buf_ring_dequeue_sc(txr->hn_txdesc_br)) != NULL) - hn_txdesc_dmamap_destroy(txd); - mtx_unlock(&txr->hn_tx_lock); -#endif + /* + * NOTE: + * Because the freeing of aggregated txds will be deferred + * to the aggregating txd, two passes are used here: + * - The first pass GCes any pending txds. This GC is necessary, + * since if the channels are revoked, hypervisor will not + * deliver send-done for all pending txds. + * - The second pass frees the busdma stuffs, i.e. after all txds + * were freed. + */ + for (i = 0; i < txr->hn_txdesc_cnt; ++i) + hn_txdesc_gc(txr, &txr->hn_txdesc[i]); + for (i = 0; i < txr->hn_txdesc_cnt; ++i) + hn_txdesc_dmamap_destroy(&txr->hn_txdesc[i]); if (txr->hn_tx_data_dtag != NULL) bus_dma_tag_destroy(txr->hn_tx_data_dtag); @@ -4499,10 +4552,17 @@ hn_set_ring_inuse(struct hn_softc *sc, i } static void -hn_chan_drain(struct vmbus_channel *chan) +hn_chan_drain(struct hn_softc *sc, struct vmbus_channel *chan) { - while (!vmbus_chan_rx_empty(chan) || !vmbus_chan_tx_empty(chan)) + /* + * NOTE: + * The TX bufring will not be drained by the hypervisor, + * if the primary channel is revoked. + */ + while (!vmbus_chan_rx_empty(chan) || + (!vmbus_chan_is_revoked(sc->hn_prichan) && + !vmbus_chan_tx_empty(chan))) pause("waitch", 1); vmbus_chan_intr_drain(chan); } @@ -4511,6 +4571,7 @@ static void hn_suspend_data(struct hn_softc *sc) { struct vmbus_channel **subch = NULL; + struct hn_tx_ring *txr; int i, nsubch; HN_LOCK_ASSERT(sc); @@ -4519,19 +4580,23 @@ hn_suspend_data(struct hn_softc *sc) * Suspend TX. */ for (i = 0; i < sc->hn_tx_ring_inuse; ++i) { - struct hn_tx_ring *txr = &sc->hn_tx_ring[i]; + txr = &sc->hn_tx_ring[i]; mtx_lock(&txr->hn_tx_lock); txr->hn_suspended = 1; mtx_unlock(&txr->hn_tx_lock); /* No one is able send more packets now. */ - /* Wait for all pending sends to finish. */ - while (hn_tx_ring_pending(txr)) + /* + * Wait for all pending sends to finish. + * + * NOTE: + * We will _not_ receive all pending send-done, if the + * primary channel is revoked. + */ + while (hn_tx_ring_pending(txr) && + !vmbus_chan_is_revoked(sc->hn_prichan)) pause("hnwtx", 1 /* 1 tick */); - - taskqueue_drain(txr->hn_tx_taskq, &txr->hn_tx_task); - taskqueue_drain(txr->hn_tx_taskq, &txr->hn_txeof_task); } /* @@ -4554,12 +4619,27 @@ hn_suspend_data(struct hn_softc *sc) if (subch != NULL) { for (i = 0; i < nsubch; ++i) - hn_chan_drain(subch[i]); + hn_chan_drain(sc, subch[i]); } - hn_chan_drain(sc->hn_prichan); + hn_chan_drain(sc, sc->hn_prichan); if (subch != NULL) vmbus_subchan_rel(subch, nsubch); + + /* + * Drain any pending TX tasks. + * + * NOTE: + * The above hn_chan_drain() can dispatch TX tasks, so the TX + * tasks will have to be drained _after_ the above hn_chan_drain() + * calls. + */ + for (i = 0; i < sc->hn_tx_ring_inuse; ++i) { + txr = &sc->hn_tx_ring[i]; + + taskqueue_drain(txr->hn_tx_taskq, &txr->hn_tx_task); + taskqueue_drain(txr->hn_tx_taskq, &txr->hn_txeof_task); + } } static void
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