Commit 3f7522f3 authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'u64_stats-introduce-u64_stats_copy' 

David Yang says:

====================
u64_stats: Introduce u64_stats_copy()

On 64bit arches, struct u64_stats_sync is empty and provides no help
against load/store tearing. memcpy() should not be considered atomic
against u64 values. Use u64_stats_copy() instead.
====================

Link: https://patch.msgid.link/20260120092137.2161162-1-mmyangfl@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents 3085ff59 58d4ca5b

drivers/net/macsec.c

+3 −3
Original line number Diff line number Diff line
@@ -2806,7 +2806,7 @@ static void get_rx_sc_stats(struct net_device *dev, 
		stats = per_cpu_ptr(rx_sc->stats, cpu);

		do {

			start = u64_stats_fetch_begin(&stats->syncp);

			memcpy(&tmp, &stats->stats, sizeof(tmp));

			u64_stats_copy(&tmp, &stats->stats, sizeof(tmp));

		} while (u64_stats_fetch_retry(&stats->syncp, start));



		sum->InOctetsValidated += tmp.InOctetsValidated;
@@ -2887,7 +2887,7 @@ static void get_tx_sc_stats(struct net_device *dev, 
		stats = per_cpu_ptr(macsec_priv(dev)->secy.tx_sc.stats, cpu);

		do {

			start = u64_stats_fetch_begin(&stats->syncp);

			memcpy(&tmp, &stats->stats, sizeof(tmp));

			u64_stats_copy(&tmp, &stats->stats, sizeof(tmp));

		} while (u64_stats_fetch_retry(&stats->syncp, start));



		sum->OutPktsProtected   += tmp.OutPktsProtected;
@@ -2943,7 +2943,7 @@ static void get_secy_stats(struct net_device *dev, struct macsec_dev_stats *sum) 
		stats = per_cpu_ptr(macsec_priv(dev)->stats, cpu);

		do {

			start = u64_stats_fetch_begin(&stats->syncp);

			memcpy(&tmp, &stats->stats, sizeof(tmp));

			u64_stats_copy(&tmp, &stats->stats, sizeof(tmp));

		} while (u64_stats_fetch_retry(&stats->syncp, start));



		sum->OutPktsUntagged  += tmp.OutPktsUntagged;

drivers/net/vxlan/vxlan_vnifilter.c

+1 −1
Original line number Diff line number Diff line
@@ -126,7 +126,7 @@ static void vxlan_vnifilter_stats_get(const struct vxlan_vni_node *vninode, 
		pstats = per_cpu_ptr(vninode->stats, i);

		do {

			start = u64_stats_fetch_begin(&pstats->syncp);

			memcpy(&temp, &pstats->stats, sizeof(temp));

			u64_stats_copy(&temp, &pstats->stats, sizeof(temp));

		} while (u64_stats_fetch_retry(&pstats->syncp, start));



		dest->rx_packets += temp.rx_packets;

include/linux/u64_stats_sync.h

+15 −0
Original line number Diff line number Diff line
@@ -79,6 +79,14 @@ static inline u64 u64_stats_read(const u64_stats_t *p) 
	return local64_read(&p->v);

}



static inline void *u64_stats_copy(void *dst, const void *src, size_t len)

{

	BUILD_BUG_ON(len % sizeof(u64_stats_t));

	for (size_t i = 0; i < len / sizeof(u64_stats_t); i++)

		((u64 *)dst)[i] = local64_read(&((local64_t *)src)[i]);

	return dst;

}



static inline void u64_stats_set(u64_stats_t *p, u64 val)

{

	local64_set(&p->v, val);
@@ -110,6 +118,7 @@ static inline bool __u64_stats_fetch_retry(const struct u64_stats_sync *syncp, 
}



#else /* 64 bit */

#include <linux/string.h>



typedef struct {

	u64		v;
@@ -120,6 +129,12 @@ static inline u64 u64_stats_read(const u64_stats_t *p) 
	return p->v;

}



static inline void *u64_stats_copy(void *dst, const void *src, size_t len)

{

	BUILD_BUG_ON(len % sizeof(u64_stats_t));

	return memcpy(dst, src, len);

}



static inline void u64_stats_set(u64_stats_t *p, u64 val)

{

	p->v = val;

net/bridge/br_multicast.c

+1 −1
Original line number Diff line number Diff line
@@ -5201,7 +5201,7 @@ void br_multicast_get_stats(const struct net_bridge *br, 


		do {

			start = u64_stats_fetch_begin(&cpu_stats->syncp);

			memcpy(&temp, &cpu_stats->mstats, sizeof(temp));

			u64_stats_copy(&temp, &cpu_stats->mstats, sizeof(temp));

		} while (u64_stats_fetch_retry(&cpu_stats->syncp, start));



		mcast_stats_add_dir(tdst.igmp_v1queries, temp.igmp_v1queries);