diff options
| author | Eric Dumazet <edumazet@google.com> | 2015-06-15 18:10:13 -0700 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2015-06-18 13:05:45 +0200 |
| commit | a1a56aaa0735c7821e85c37268a7c12e132415cb (patch) | |
| tree | 2d8d0372fb798896d8a93aa1ba6d493bbb901026 /include/linux/netfilter | |
| parent | 01555e74bde51444c6898ef1800fb2bc697d479e (diff) | |
netfilter: x_tables: align per cpu xt_counter
Let's force a 16 bytes alignment on xt_counter percpu allocations,
so that bytes and packets sit in same cache line.
xt_counter being exported to user space, we cannot add __align(16) on
the structure itself.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'include/linux/netfilter')
| -rw-r--r-- | include/linux/netfilter/x_tables.h | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h index 95693c4cebdd..1c97a2204379 100644 --- a/include/linux/netfilter/x_tables.h +++ b/include/linux/netfilter/x_tables.h @@ -356,7 +356,8 @@ static inline unsigned long ifname_compare_aligned(const char *_a, * so nothing needs to be done there. * * xt_percpu_counter_alloc returns the address of the percpu - * counter, or 0 on !SMP. + * counter, or 0 on !SMP. We force an alignment of 16 bytes + * so that bytes/packets share a common cache line. * * Hence caller must use IS_ERR_VALUE to check for error, this * allows us to return 0 for single core systems without forcing @@ -365,7 +366,8 @@ static inline unsigned long ifname_compare_aligned(const char *_a, static inline u64 xt_percpu_counter_alloc(void) { if (nr_cpu_ids > 1) { - void __percpu *res = alloc_percpu(struct xt_counters); + void __percpu *res = __alloc_percpu(sizeof(struct xt_counters), + sizeof(struct xt_counters)); if (res == NULL) return (u64) -ENOMEM; |