summaryrefslogtreecommitdiff
path: root/net/openvswitch/flow_table.h
AgeCommit message (Collapse)Author
2015-09-22openvswitch: Zero flows on allocation.Jesse Gross
When support for megaflows was introduced, OVS needed to start installing flows with a mask applied to them. Since masking is an expensive operation, OVS also had an optimization that would only take the parts of the flow keys that were covered by a non-zero mask. The values stored in the remaining pieces should not matter because they are masked out. While this works fine for the purposes of matching (which must always look at the mask), serialization to netlink can be problematic. Since the flow and the mask are serialized separately, the uninitialized portions of the flow can be encoded with whatever values happen to be present. In terms of functionality, this has little effect since these fields will be masked out by definition. However, it leaks kernel memory to userspace, which is a potential security vulnerability. It is also possible that other code paths could look at the masked key and get uninitialized data, although this does not currently appear to be an issue in practice. This removes the mask optimization for flows that are being installed. This was always intended to be the case as the mask optimizations were really targetting per-packet flow operations. Fixes: 03f0d916 ("openvswitch: Mega flow implementation") Signed-off-by: Jesse Gross <jesse@nicira.com> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-26openvswitch: Add support for unique flow IDs.Joe Stringer
Previously, flows were manipulated by userspace specifying a full, unmasked flow key. This adds significant burden onto flow serialization/deserialization, particularly when dumping flows. This patch adds an alternative way to refer to flows using a variable-length "unique flow identifier" (UFID). At flow setup time, userspace may specify a UFID for a flow, which is stored with the flow and inserted into a separate table for lookup, in addition to the standard flow table. Flows created using a UFID must be fetched or deleted using the UFID. All flow dump operations may now be made more terse with OVS_UFID_F_* flags. For example, the OVS_UFID_F_OMIT_KEY flag allows responses to omit the flow key from a datapath operation if the flow has a corresponding UFID. This significantly reduces the time spent assembling and transacting netlink messages. With all OVS_UFID_F_OMIT_* flags enabled, the datapath only returns the UFID and statistics for each flow during flow dump, increasing ovs-vswitchd revalidator performance by 40% or more. Signed-off-by: Joe Stringer <joestringer@nicira.com> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-09openvswitch: Constify various function argumentsThomas Graf
Help produce better optimized code. Signed-off-by: Thomas Graf <tgraf@noironetworks.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-11-05openvswitch: Move table destroy to dp-rcu callback.Pravin B Shelar
Ths simplifies flow-table-destroy API. No need to pass explicit parameter about context. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Acked-by: Thomas Graf <tgraf@redhat.com>
2014-06-30openvswitch: Use exact lookup for flow_get and flow_del.Alex Wang
Due to the race condition in userspace, there is chance that two overlapping megaflows could be installed in datapath. And this causes userspace unable to delete the less inclusive megaflow flow even after it timeout, since the flow_del logic will stop at the first match of masked flow. This commit fixes the bug by making the kernel flow_del and flow_get logic check all masks in that case. Introduced by 03f0d916a (openvswitch: Mega flow implementation). Signed-off-by: Alex Wang <alexw@nicira.com> Acked-by: Andy Zhou <azhou@nicira.com> Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-05-16openvswitch: Per NUMA node flow stats.Jarno Rajahalme
Keep kernel flow stats for each NUMA node rather than each (logical) CPU. This avoids using the per-CPU allocator and removes most of the kernel-side OVS locking overhead otherwise on the top of perf reports and allows OVS to scale better with higher number of threads. With 9 handlers and 4 revalidators netperf TCP_CRR test flow setup rate doubles on a server with two hyper-threaded physical CPUs (16 logical cores each) compared to the current OVS master. Tested with non-trivial flow table with a TCP port match rule forcing all new connections with unique port numbers to OVS userspace. The IP addresses are still wildcarded, so the kernel flows are not considered as exact match 5-tuple flows. This type of flows can be expected to appear in large numbers as the result of more effective wildcarding made possible by improvements in OVS userspace flow classifier. Perf results for this test (master): Events: 305K cycles + 8.43% ovs-vswitchd [kernel.kallsyms] [k] mutex_spin_on_owner + 5.64% ovs-vswitchd [kernel.kallsyms] [k] __ticket_spin_lock + 4.75% ovs-vswitchd ovs-vswitchd [.] find_match_wc + 3.32% ovs-vswitchd libpthread-2.15.so [.] pthread_mutex_lock + 2.61% ovs-vswitchd [kernel.kallsyms] [k] pcpu_alloc_area + 2.19% ovs-vswitchd ovs-vswitchd [.] flow_hash_in_minimask_range + 2.03% swapper [kernel.kallsyms] [k] intel_idle + 1.84% ovs-vswitchd libpthread-2.15.so [.] pthread_mutex_unlock + 1.64% ovs-vswitchd ovs-vswitchd [.] classifier_lookup + 1.58% ovs-vswitchd libc-2.15.so [.] 0x7f4e6 + 1.07% ovs-vswitchd [kernel.kallsyms] [k] memset + 1.03% netperf [kernel.kallsyms] [k] __ticket_spin_lock + 0.92% swapper [kernel.kallsyms] [k] __ticket_spin_lock ... And after this patch: Events: 356K cycles + 6.85% ovs-vswitchd ovs-vswitchd [.] find_match_wc + 4.63% ovs-vswitchd libpthread-2.15.so [.] pthread_mutex_lock + 3.06% ovs-vswitchd [kernel.kallsyms] [k] __ticket_spin_lock + 2.81% ovs-vswitchd ovs-vswitchd [.] flow_hash_in_minimask_range + 2.51% ovs-vswitchd libpthread-2.15.so [.] pthread_mutex_unlock + 2.27% ovs-vswitchd ovs-vswitchd [.] classifier_lookup + 1.84% ovs-vswitchd libc-2.15.so [.] 0x15d30f + 1.74% ovs-vswitchd [kernel.kallsyms] [k] mutex_spin_on_owner + 1.47% swapper [kernel.kallsyms] [k] intel_idle + 1.34% ovs-vswitchd ovs-vswitchd [.] flow_hash_in_minimask + 1.33% ovs-vswitchd ovs-vswitchd [.] rule_actions_unref + 1.16% ovs-vswitchd ovs-vswitchd [.] hindex_node_with_hash + 1.16% ovs-vswitchd ovs-vswitchd [.] do_xlate_actions + 1.09% ovs-vswitchd ovs-vswitchd [.] ofproto_rule_ref + 1.01% netperf [kernel.kallsyms] [k] __ticket_spin_lock ... There is a small increase in kernel spinlock overhead due to the same spinlock being shared between multiple cores of the same physical CPU, but that is barely visible in the netperf TCP_CRR test performance (maybe ~1% performance drop, hard to tell exactly due to variance in the test results), when testing for kernel module throughput (with no userspace activity, handful of kernel flows). On flow setup, a single stats instance is allocated (for the NUMA node 0). As CPUs from multiple NUMA nodes start updating stats, new NUMA-node specific stats instances are allocated. This allocation on the packet processing code path is made to never block or look for emergency memory pools, minimizing the allocation latency. If the allocation fails, the existing preallocated stats instance is used. Also, if only CPUs from one NUMA-node are updating the preallocated stats instance, no additional stats instances are allocated. This eliminates the need to pre-allocate stats instances that will not be used, also relieving the stats reader from the burden of reading stats that are never used. Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2014-05-16openvswitch: Remove 5-tuple optimization.Jarno Rajahalme
The 5-tuple optimization becomes unnecessary with a later per-NUMA node stats patch. Remove it first to make the changes easier to grasp. Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2014-02-04openvswitch: Fix kernel panic on ovs_flow_freeAndy Zhou
Both mega flow mask's reference counter and per flow table mask list should only be accessed when holding ovs_mutex() lock. However this is not true with ovs_flow_table_flush(). The patch fixes this bug. Reported-by: Joe Stringer <joestringer@nicira.com> Signed-off-by: Andy Zhou <azhou@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2014-01-06openvswitch: Per cpu flow stats.Pravin B Shelar
With mega flow implementation ovs flow can be shared between multiple CPUs which makes stats updates highly contended operation. This patch uses per-CPU stats in cases where a flow is likely to be shared (if there is a wildcard in the 5-tuple and therefore likely to be spread by RSS). In other situations, it uses the current strategy, saving memory and allocation time. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2014-01-06openvswitch: Change ovs_flow_tbl_lookup_xx() APIsAndy Zhou
API changes only for code readability. No functional chnages. This patch removes the underscored version. Added a new API ovs_flow_tbl_lookup_stats() that returns the n_mask_hits. Reported by: Ben Pfaff <blp@nicira.com> Reviewed-by: Thomas Graf <tgraf@redhat.com> Signed-off-by: Andy Zhou <azhou@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-10-22openvswitch: collect mega flow mask statsAndy Zhou
Collect mega flow mask stats. ovs-dpctl show command can be used to display them for debugging and performance tuning. Signed-off-by: Andy Zhou <azhou@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-10-04openvswitch: Simplify mega-flow APIs.Pravin B Shelar
Hides mega-flow implementation in flow_table.c rather than datapath.c. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-10-04openvswitch: Move mega-flow list out of rehashing struct.Pravin B Shelar
ovs-flow rehash does not touch mega flow list. Following patch moves it dp struct datapath. Avoid one extra indirection for accessing mega-flow list head on every packet receive. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>
2013-10-03openvswitch: Restructure datapath.c and flow.cPravin B Shelar
Over the time datapath.c and flow.c has became pretty large files. Following patch restructures functionality of component into three different components: flow.c: contains flow extract. flow_netlink.c: netlink flow api. flow_table.c: flow table api. This patch restructures code without changing logic. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Jesse Gross <jesse@nicira.com>