From 490f58382dca2a415a5f16b6133f298d853bb379 Mon Sep 17 00:00:00 2001 From: Laine Stump Date: Mon, 25 Nov 2024 22:24:45 -0500 Subject: [PATCH 5/9] util: make it optional to clear existing tc qdiscs/filters in virNetDevBandwidthSet() virNetDevBandwidthSet() always clears all existing qdiscs and their subordinate filters before adding all the new qdiscs/filters. This is normally exactly what we want, but there is one case (the network driver) where the Qdisc added by virNetDevBandwidthSet() may already be in use by the nftables backend (which will add a rule to fix the checksum of dhcp packets); in that case, we *don't* want virNetDevBandwidthSet() to clear out the qdisc that was already added for nftables, and none of the bandwidth filters have been added yet, so there already aren't any "old" filters that need to be removed either - it is safe to just skip virNetDevBandwidthClear() in this case. To allow the network driver to set bandwidth without first clearing it, this patch adds the flag VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL to the virNetDevBandwidthSetFlags enum, and recognizes it in virNetDevBandwidthSet() - if the flag is set, then virNetDevBandwidth() will call virNetDevBandwidthClear() just as it always has. But if the flag isn't set it *won't* call virNetDevBandwidthClear(). As suggested above, VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL is set for all calls to virNetdevBandwidthSet() except for two places in the network driver. Signed-off-by: Laine Stump Reviewed-by: Michal Privoznik --- src/lxc/lxc_driver.c | 2 +- src/lxc/lxc_process.c | 2 +- src/qemu/qemu_command.c | 2 +- src/qemu/qemu_driver.c | 2 +- src/qemu/qemu_hotplug.c | 4 ++-- src/util/virnetdevbandwidth.c | 21 ++++++++++++++++++++- src/util/virnetdevbandwidth.h | 1 + tests/virnetdevbandwidthtest.c | 3 ++- 8 files changed, 29 insertions(+), 8 deletions(-) diff --git a/src/lxc/lxc_driver.c b/src/lxc/lxc_driver.c index b693980dbb..81581c74df 100644 --- a/src/lxc/lxc_driver.c +++ b/src/lxc/lxc_driver.c @@ -3570,7 +3570,7 @@ lxcDomainAttachDeviceNetLive(virLXCDriver *driver, actualBandwidth = virDomainNetGetActualBandwidth(net); if (actualBandwidth) { if (virNetDevSupportsBandwidth(actualType)) { - unsigned int flags = 0; + unsigned int flags = VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL; if (!virDomainNetTypeSharesHostView(net)) flags |= VIR_NETDEV_BANDWIDTH_SET_DIR_SWAPPED; diff --git a/src/lxc/lxc_process.c b/src/lxc/lxc_process.c index 0e689fbb70..081ce03a57 100644 --- a/src/lxc/lxc_process.c +++ b/src/lxc/lxc_process.c @@ -605,7 +605,7 @@ virLXCProcessSetupInterfaces(virLXCDriver *driver, actualBandwidth = virDomainNetGetActualBandwidth(net); if (actualBandwidth) { if (virNetDevSupportsBandwidth(type)) { - unsigned int flags = 0; + unsigned int flags = VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL; if (!virDomainNetTypeSharesHostView(net)) flags |= VIR_NETDEV_BANDWIDTH_SET_DIR_SWAPPED; diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index b4815e5e71..ed54fd4c5b 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -8841,7 +8841,7 @@ qemuBuildInterfaceCommandLine(virQEMUDriver *driver, !virDomainNetTypeSharesHostView(net)) < 0) goto cleanup; } else { - unsigned int flags = 0; + unsigned int flags = VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL; if (!virDomainNetTypeSharesHostView(net)) flags |= VIR_NETDEV_BANDWIDTH_SET_DIR_SWAPPED; diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 14929616e5..9549065b1f 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -9942,7 +9942,7 @@ qemuDomainSetInterfaceParameters(virDomainPtr dom, goto endjob; } } else { - unsigned int bwflags = 0; + unsigned int bwflags = VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL; if (!virDomainNetTypeSharesHostView(net)) bwflags |= VIR_NETDEV_BANDWIDTH_SET_DIR_SWAPPED; diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c index d5e7e99359..ceda4119cd 100644 --- a/src/qemu/qemu_hotplug.c +++ b/src/qemu/qemu_hotplug.c @@ -1280,7 +1280,7 @@ qemuDomainAttachNetDevice(virQEMUDriver *driver, !virDomainNetTypeSharesHostView(net)) < 0) goto cleanup; } else { - int flags = 0; + int flags = VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL; if (!virDomainNetTypeSharesHostView(net)) flags |= VIR_NETDEV_BANDWIDTH_SET_DIR_SWAPPED; @@ -4088,7 +4088,7 @@ qemuDomainChangeNet(virQEMUDriver *driver, !virDomainNetTypeSharesHostView(newdev)) < 0) goto cleanup; } else { - int flags = 0; + int flags = VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL; if (!virDomainNetTypeSharesHostView(newdev)) flags |= VIR_NETDEV_BANDWIDTH_SET_DIR_SWAPPED; diff --git a/src/util/virnetdevbandwidth.c b/src/util/virnetdevbandwidth.c index 1baad849c6..9c48844c5d 100644 --- a/src/util/virnetdevbandwidth.c +++ b/src/util/virnetdevbandwidth.c @@ -196,6 +196,21 @@ virNetDevBandwidthManipulateFilter(const char *ifname, * interface (so domain's RX/TX is host's RX/TX), and for some * it's swapped (domain's RX/TX is hosts's TX/RX). * + * VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL + * If VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL is set, then the root + * qdisc is deleted before adding any new qdisc/class/filter, + * which causes any pre-existing filters to also be deleted. If + * not set, then it's assumed that there are no existing rules (or + * that those already there need to be kept). The caller should + * set this flag for an existing interface that is having its + * bandwidth settings modified, but can leave it unset if the + * interface was newly created and this is the first time + * bandwidth has been set, but someone else might have already + * added the qdisc (e.g. this is the case when the network driver + * is setting bandwidth for a virtual network bridge device - the + * nftables backend may have already added qdisc handle 1:0 and a + * filter, and we don't want to delete them) + * * Return 0 on success, -1 otherwise. */ int @@ -238,7 +253,11 @@ virNetDevBandwidthSet(const char *ifname, tx = bandwidth->out; } - virNetDevBandwidthClear(ifname); + /* Only if the caller requests, clear everything including root + * qdisc and all filters before adding everything. + */ + if (flags & VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL) + virNetDevBandwidthClear(ifname); if (tx && tx->average) { average = g_strdup_printf("%llukbps", tx->average); diff --git a/src/util/virnetdevbandwidth.h b/src/util/virnetdevbandwidth.h index 80dc654486..744aa4c826 100644 --- a/src/util/virnetdevbandwidth.h +++ b/src/util/virnetdevbandwidth.h @@ -42,6 +42,7 @@ G_DEFINE_AUTOPTR_CLEANUP_FUNC(virNetDevBandwidth, virNetDevBandwidthFree); typedef enum { VIR_NETDEV_BANDWIDTH_SET_HIERARCHICAL_CLASS = (1 << 0), VIR_NETDEV_BANDWIDTH_SET_DIR_SWAPPED = (1 << 1), + VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL = (1 << 2), } virNetDevBandwidthSetFlags; int virNetDevBandwidthSet(const char *ifname, diff --git a/tests/virnetdevbandwidthtest.c b/tests/virnetdevbandwidthtest.c index 6529ff4026..6d5c847ad7 100644 --- a/tests/virnetdevbandwidthtest.c +++ b/tests/virnetdevbandwidthtest.c @@ -82,7 +82,8 @@ testVirNetDevBandwidthSet(const void *data) if (virNetDevOpenvswitchInterfaceSetQos(iface, band, info->uuid, true) < 0) return -1; } else { - unsigned int flags = VIR_NETDEV_BANDWIDTH_SET_DIR_SWAPPED; + unsigned int flags = VIR_NETDEV_BANDWIDTH_SET_DIR_SWAPPED | + VIR_NETDEV_BANDWIDTH_SET_CLEAR_ALL; if (info->hierarchical_class) flags |= VIR_NETDEV_BANDWIDTH_SET_HIERARCHICAL_CLASS; -- 2.47.1