diff options
| author | Eddy Tao <taoyuan_eddy@hotmail.com> | 2023-02-05 09:35:37 +0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2023-02-06 22:36:29 -0800 |
| commit | 15ea59a0e9bf0dce546b6fcab5b00af8b35b870d (patch) | |
| tree | 45007b7f95d095f80b10b53f1bb5a4c2cb7203bf /net/openvswitch/flow_table.c | |
| parent | bbe641866318b2693e2778862e3b8ed6ccd0843b (diff) | |
net: openvswitch: reduce cpu_used_mask memory
Use actual CPU number instead of hardcoded value to decide the size
of 'cpu_used_mask' in 'struct sw_flow'. Below is the reason.
'struct cpumask cpu_used_mask' is embedded in struct sw_flow.
Its size is hardcoded to CONFIG_NR_CPUS bits, which can be
8192 by default, it costs memory and slows down ovs_flow_alloc.
To address this:
Redefine cpu_used_mask to pointer.
Append cpumask_size() bytes after 'stat' to hold cpumask.
Initialization cpu_used_mask right after stats_last_writer.
APIs like cpumask_next and cpumask_set_cpu never access bits
beyond cpu count, cpumask_size() bytes of memory is enough.
Signed-off-by: Eddy Tao <taoyuan_eddy@hotmail.com>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Link: https://lore.kernel.org/r/OS3P286MB229570CCED618B20355D227AF5D59@OS3P286MB2295.JPNP286.PROD.OUTLOOK.COM
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/openvswitch/flow_table.c')
| -rw-r--r-- | net/openvswitch/flow_table.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c index 0a0e4c283f02..791504b7f42b 100644 --- a/net/openvswitch/flow_table.c +++ b/net/openvswitch/flow_table.c @@ -79,6 +79,7 @@ struct sw_flow *ovs_flow_alloc(void) return ERR_PTR(-ENOMEM); flow->stats_last_writer = -1; + flow->cpu_used_mask = (struct cpumask *)&flow->stats[nr_cpu_ids]; /* Initialize the default stat node. */ stats = kmem_cache_alloc_node(flow_stats_cache, @@ -91,7 +92,7 @@ struct sw_flow *ovs_flow_alloc(void) RCU_INIT_POINTER(flow->stats[0], stats); - cpumask_set_cpu(0, &flow->cpu_used_mask); + cpumask_set_cpu(0, flow->cpu_used_mask); return flow; err: @@ -115,7 +116,7 @@ static void flow_free(struct sw_flow *flow) flow->sf_acts); /* We open code this to make sure cpu 0 is always considered */ for (cpu = 0; cpu < nr_cpu_ids; - cpu = cpumask_next(cpu, &flow->cpu_used_mask)) { + cpu = cpumask_next(cpu, flow->cpu_used_mask)) { if (flow->stats[cpu]) kmem_cache_free(flow_stats_cache, (struct sw_flow_stats __force *)flow->stats[cpu]); @@ -1196,7 +1197,8 @@ int ovs_flow_init(void) flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow) + (nr_cpu_ids - * sizeof(struct sw_flow_stats *)), + * sizeof(struct sw_flow_stats *)) + + cpumask_size(), 0, 0, NULL); if (flow_cache == NULL) return -ENOMEM; |