net: snmp: kill various STATS_USER() helpers

In the old days (before linux-3.0), SNMP counters were duplicated,
one for user context, and one for BH context.

After commit 8f0ea0fe3a03 ("snmp: reduce percpu needs by 50%")
we have a single copy, and what really matters is preemption being
enabled or disabled, since we use this_cpu_inc() or __this_cpu_inc()
respectively.

We therefore kill SNMP_INC_STATS_USER(), SNMP_ADD_STATS_USER(),
NET_INC_STATS_USER(), NET_ADD_STATS_USER(), SCTP_INC_STATS_USER(),
SNMP_INC_STATS64_USER(), SNMP_ADD_STATS64_USER(), TCP_ADD_STATS_USER(),
UDP_INC_STATS_USER(), UDP6_INC_STATS_USER(), and XFRM_INC_STATS_USER()

Following patches will rename __BH helpers to make clear their
usage is not tied to BH being disabled.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

6 files changed, 16 insertions, 34 deletions

diff --git a/include/net/ip.h b/include/net/ip.h
index 93725e546758..ae0e85d018e8 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -194,10 +194,8 @@ void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
 #define IP_UPD_PO_STATS_BH(net, field, val) SNMP_UPD_PO_STATS64_BH((net)->mib.ip_statistics, field, val)
 #define NET_INC_STATS(net, field)	SNMP_INC_STATS((net)->mib.net_statistics, field)
 #define NET_INC_STATS_BH(net, field)	SNMP_INC_STATS_BH((net)->mib.net_statistics, field)
-#define NET_INC_STATS_USER(net, field) 	SNMP_INC_STATS_USER((net)->mib.net_statistics, field)
 #define NET_ADD_STATS(net, field, adnd)	SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd)
 #define NET_ADD_STATS_BH(net, field, adnd) SNMP_ADD_STATS_BH((net)->mib.net_statistics, field, adnd)
-#define NET_ADD_STATS_USER(net, field, adnd) SNMP_ADD_STATS_USER((net)->mib.net_statistics, field, adnd)
 
 u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct);
 unsigned long snmp_fold_field(void __percpu *mib, int offt);
diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index 3f1c0ff7d4b6..5a2c4c3307a7 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -207,7 +207,6 @@ extern int sysctl_sctp_wmem[3];
 /* SCTP SNMP MIB stats handlers */
 #define SCTP_INC_STATS(net, field)      SNMP_INC_STATS((net)->sctp.sctp_statistics, field)
 #define SCTP_INC_STATS_BH(net, field)   SNMP_INC_STATS_BH((net)->sctp.sctp_statistics, field)
-#define SCTP_INC_STATS_USER(net, field) SNMP_INC_STATS_USER((net)->sctp.sctp_statistics, field)
 #define SCTP_DEC_STATS(net, field)      SNMP_DEC_STATS((net)->sctp.sctp_statistics, field)
 
 /* sctp mib definitions */
diff --git a/include/net/snmp.h b/include/net/snmp.h
index 35512ac6dcfb..56239fc05c51 100644
--- a/include/net/snmp.h
+++ b/include/net/snmp.h
@@ -126,9 +126,6 @@ struct linux_xfrm_mib {
 #define SNMP_INC_STATS_BH(mib, field)	\
 			__this_cpu_inc(mib->mibs[field])
 
-#define SNMP_INC_STATS_USER(mib, field)	\
-			this_cpu_inc(mib->mibs[field])
-
 #define SNMP_INC_STATS_ATOMIC_LONG(mib, field)	\
 			atomic_long_inc(&mib->mibs[field])
 
@@ -141,9 +138,6 @@ struct linux_xfrm_mib {
 #define SNMP_ADD_STATS_BH(mib, field, addend)	\
 			__this_cpu_add(mib->mibs[field], addend)
 
-#define SNMP_ADD_STATS_USER(mib, field, addend)	\
-			this_cpu_add(mib->mibs[field], addend)
-
 #define SNMP_ADD_STATS(mib, field, addend)	\
 			this_cpu_add(mib->mibs[field], addend)
 #define SNMP_UPD_PO_STATS(mib, basefield, addend)	\
@@ -170,18 +164,14 @@ struct linux_xfrm_mib {
 		u64_stats_update_end(&ptr->syncp);			\
 	} while (0)
 
-#define SNMP_ADD_STATS64_USER(mib, field, addend) 			\
+#define SNMP_ADD_STATS64(mib, field, addend) 			\
 	do {								\
-		local_bh_disable();					\
+		preempt_disable();					\
 		SNMP_ADD_STATS64_BH(mib, field, addend);		\
-		local_bh_enable();					\
+		preempt_enable();					\
 	} while (0)
 
-#define SNMP_ADD_STATS64(mib, field, addend)				\
-		SNMP_ADD_STATS64_USER(mib, field, addend)
-
 #define SNMP_INC_STATS64_BH(mib, field) SNMP_ADD_STATS64_BH(mib, field, 1)
-#define SNMP_INC_STATS64_USER(mib, field) SNMP_ADD_STATS64_USER(mib, field, 1)
 #define SNMP_INC_STATS64(mib, field) SNMP_ADD_STATS64(mib, field, 1)
 #define SNMP_UPD_PO_STATS64_BH(mib, basefield, addend)			\
 	do {								\
@@ -194,17 +184,15 @@ struct linux_xfrm_mib {
 	} while (0)
 #define SNMP_UPD_PO_STATS64(mib, basefield, addend)			\
 	do {								\
-		local_bh_disable();					\
+		preempt_disable();					\
 		SNMP_UPD_PO_STATS64_BH(mib, basefield, addend);		\
-		local_bh_enable();					\
+		preempt_enable();					\
 	} while (0)
 #else
 #define SNMP_INC_STATS64_BH(mib, field)		SNMP_INC_STATS_BH(mib, field)
-#define SNMP_INC_STATS64_USER(mib, field)	SNMP_INC_STATS_USER(mib, field)
 #define SNMP_INC_STATS64(mib, field)		SNMP_INC_STATS(mib, field)
 #define SNMP_DEC_STATS64(mib, field)		SNMP_DEC_STATS(mib, field)
 #define SNMP_ADD_STATS64_BH(mib, field, addend) SNMP_ADD_STATS_BH(mib, field, addend)
-#define SNMP_ADD_STATS64_USER(mib, field, addend) SNMP_ADD_STATS_USER(mib, field, addend)
 #define SNMP_ADD_STATS64(mib, field, addend)	SNMP_ADD_STATS(mib, field, addend)
 #define SNMP_UPD_PO_STATS64(mib, basefield, addend) SNMP_UPD_PO_STATS(mib, basefield, addend)
 #define SNMP_UPD_PO_STATS64_BH(mib, basefield, addend) SNMP_UPD_PO_STATS_BH(mib, basefield, addend)
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 7f2553da10d1..cfe15f712164 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -334,7 +334,6 @@ extern struct proto tcp_prot;
 #define TCP_INC_STATS(net, field)	SNMP_INC_STATS((net)->mib.tcp_statistics, field)
 #define TCP_INC_STATS_BH(net, field)	SNMP_INC_STATS_BH((net)->mib.tcp_statistics, field)
 #define TCP_DEC_STATS(net, field)	SNMP_DEC_STATS((net)->mib.tcp_statistics, field)
-#define TCP_ADD_STATS_USER(net, field, val) SNMP_ADD_STATS_USER((net)->mib.tcp_statistics, field, val)
 #define TCP_ADD_STATS(net, field, val)	SNMP_ADD_STATS((net)->mib.tcp_statistics, field, val)
 
 void tcp_tasklet_init(void);
@@ -1298,10 +1297,10 @@ bool tcp_oow_rate_limited(struct net *net, const struct sk_buff *skb,
 static inline void tcp_mib_init(struct net *net)
 {
 	/* See RFC 2012 */
-	TCP_ADD_STATS_USER(net, TCP_MIB_RTOALGORITHM, 1);
-	TCP_ADD_STATS_USER(net, TCP_MIB_RTOMIN, TCP_RTO_MIN*1000/HZ);
-	TCP_ADD_STATS_USER(net, TCP_MIB_RTOMAX, TCP_RTO_MAX*1000/HZ);
-	TCP_ADD_STATS_USER(net, TCP_MIB_MAXCONN, -1);
+	TCP_ADD_STATS(net, TCP_MIB_RTOALGORITHM, 1);
+	TCP_ADD_STATS(net, TCP_MIB_RTOMIN, TCP_RTO_MIN*1000/HZ);
+	TCP_ADD_STATS(net, TCP_MIB_RTOMAX, TCP_RTO_MAX*1000/HZ);
+	TCP_ADD_STATS(net, TCP_MIB_MAXCONN, -1);
 }
 
 /* from STCP */
diff --git a/include/net/udp.h b/include/net/udp.h
index 3c5a65e0946d..2f37f689d85a 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -289,20 +289,20 @@ struct sock *udp6_lib_lookup_skb(struct sk_buff *skb,
 /*
  * 	SNMP statistics for UDP and UDP-Lite
  */
-#define UDP_INC_STATS_USER(net, field, is_udplite)	      do { \
-	if (is_udplite) SNMP_INC_STATS_USER((net)->mib.udplite_statistics, field);       \
-	else		SNMP_INC_STATS_USER((net)->mib.udp_statistics, field);  }  while(0)
+#define UDP_INC_STATS(net, field, is_udplite)		      do { \
+	if (is_udplite) SNMP_INC_STATS((net)->mib.udplite_statistics, field);       \
+	else		SNMP_INC_STATS((net)->mib.udp_statistics, field);  }  while(0)
 #define UDP_INC_STATS_BH(net, field, is_udplite) 	      do { \
 	if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_statistics, field);         \
 	else		SNMP_INC_STATS_BH((net)->mib.udp_statistics, field);    }  while(0)
 
-#define UDP6_INC_STATS_BH(net, field, is_udplite) 	    do { \
+#define UDP6_INC_STATS_BH(net, field, is_udplite)	    do { \
 	if (is_udplite) SNMP_INC_STATS_BH((net)->mib.udplite_stats_in6, field);\
 	else		SNMP_INC_STATS_BH((net)->mib.udp_stats_in6, field);  \
 } while(0)
-#define UDP6_INC_STATS_USER(net, field, __lite)		    do { \
-	if (__lite) SNMP_INC_STATS_USER((net)->mib.udplite_stats_in6, field);  \
-	else	    SNMP_INC_STATS_USER((net)->mib.udp_stats_in6, field);      \
+#define UDP6_INC_STATS(net, field, __lite)		    do { \
+	if (__lite) SNMP_INC_STATS((net)->mib.udplite_stats_in6, field);  \
+	else	    SNMP_INC_STATS((net)->mib.udp_stats_in6, field);      \
 } while(0)
 
 #if IS_ENABLED(CONFIG_IPV6)
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index d6f6e5006ee9..dab9e1b82963 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -46,11 +46,9 @@
 #ifdef CONFIG_XFRM_STATISTICS
 #define XFRM_INC_STATS(net, field)	SNMP_INC_STATS((net)->mib.xfrm_statistics, field)
 #define XFRM_INC_STATS_BH(net, field)	SNMP_INC_STATS_BH((net)->mib.xfrm_statistics, field)
-#define XFRM_INC_STATS_USER(net, field)	SNMP_INC_STATS_USER((net)-mib.xfrm_statistics, field)
 #else
 #define XFRM_INC_STATS(net, field)	((void)(net))
 #define XFRM_INC_STATS_BH(net, field)	((void)(net))
-#define XFRM_INC_STATS_USER(net, field)	((void)(net))
 #endif