net: move rps_sock_flow_table to net_hotdata

rps_sock_flow_table and rps_cpu_mask are used in fast path.

Move them to net_hotdata for better cache locality.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240306160031.874438-19-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Eric Dumazet 2024-03-06 16:00:31 +00:00 committed by Jakub Kicinski
parent 490a79faf9
commit ce7f49ab74
4 changed files with 16 additions and 17 deletions

View File

@ -27,6 +27,10 @@ struct net_hotdata {
struct kmem_cache *skbuff_cache;
struct kmem_cache *skbuff_fclone_cache;
struct kmem_cache *skb_small_head_cache;
#ifdef CONFIG_RPS
struct rps_sock_flow_table __rcu *rps_sock_flow_table;
u32 rps_cpu_mask;
#endif
int gro_normal_batch;
int netdev_budget;
int netdev_budget_usecs;

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@ -5,6 +5,7 @@
#include <linux/types.h>
#include <linux/static_key.h>
#include <net/sock.h>
#include <net/hotdata.h>
#ifdef CONFIG_RPS
@ -64,14 +65,11 @@ struct rps_sock_flow_table {
#define RPS_NO_CPU 0xffff
extern u32 rps_cpu_mask;
extern struct rps_sock_flow_table __rcu *rps_sock_flow_table;
static inline void rps_record_sock_flow(struct rps_sock_flow_table *table,
u32 hash)
{
unsigned int index = hash & table->mask;
u32 val = hash & ~rps_cpu_mask;
u32 val = hash & ~net_hotdata.rps_cpu_mask;
/* We only give a hint, preemption can change CPU under us */
val |= raw_smp_processor_id();
@ -93,7 +91,7 @@ static inline void sock_rps_record_flow_hash(__u32 hash)
if (!hash)
return;
rcu_read_lock();
sock_flow_table = rcu_dereference(rps_sock_flow_table);
sock_flow_table = rcu_dereference(net_hotdata.rps_sock_flow_table);
if (sock_flow_table)
rps_record_sock_flow(sock_flow_table, hash);
rcu_read_unlock();

View File

@ -4450,12 +4450,6 @@ static inline void ____napi_schedule(struct softnet_data *sd,
#ifdef CONFIG_RPS
/* One global table that all flow-based protocols share. */
struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
EXPORT_SYMBOL(rps_sock_flow_table);
u32 rps_cpu_mask __read_mostly;
EXPORT_SYMBOL(rps_cpu_mask);
struct static_key_false rps_needed __read_mostly;
EXPORT_SYMBOL(rps_needed);
struct static_key_false rfs_needed __read_mostly;
@ -4547,7 +4541,7 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
if (!hash)
goto done;
sock_flow_table = rcu_dereference(rps_sock_flow_table);
sock_flow_table = rcu_dereference(net_hotdata.rps_sock_flow_table);
if (flow_table && sock_flow_table) {
struct rps_dev_flow *rflow;
u32 next_cpu;
@ -4557,10 +4551,10 @@ static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
* This READ_ONCE() pairs with WRITE_ONCE() from rps_record_sock_flow().
*/
ident = READ_ONCE(sock_flow_table->ents[hash & sock_flow_table->mask]);
if ((ident ^ hash) & ~rps_cpu_mask)
if ((ident ^ hash) & ~net_hotdata.rps_cpu_mask)
goto try_rps;
next_cpu = ident & rps_cpu_mask;
next_cpu = ident & net_hotdata.rps_cpu_mask;
/* OK, now we know there is a match,
* we can look at the local (per receive queue) flow table

View File

@ -140,7 +140,8 @@ static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
mutex_lock(&sock_flow_mutex);
orig_sock_table = rcu_dereference_protected(rps_sock_flow_table,
orig_sock_table = rcu_dereference_protected(
net_hotdata.rps_sock_flow_table,
lockdep_is_held(&sock_flow_mutex));
size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0;
@ -161,7 +162,8 @@ static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
mutex_unlock(&sock_flow_mutex);
return -ENOMEM;
}
rps_cpu_mask = roundup_pow_of_two(nr_cpu_ids) - 1;
net_hotdata.rps_cpu_mask =
roundup_pow_of_two(nr_cpu_ids) - 1;
sock_table->mask = size - 1;
} else
sock_table = orig_sock_table;
@ -172,7 +174,8 @@ static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
sock_table = NULL;
if (sock_table != orig_sock_table) {
rcu_assign_pointer(rps_sock_flow_table, sock_table);
rcu_assign_pointer(net_hotdata.rps_sock_flow_table,
sock_table);
if (sock_table) {
static_branch_inc(&rps_needed);
static_branch_inc(&rfs_needed);