2 files changed, 56 insertions, 82 deletions

diff --git a/include/net/snmp.h b/include/net/snmp.h
index 479083a78b0c..8f0f9ac0307f 100644
--- a/include/net/snmp.h
+++ b/include/net/snmp.h
@@ -116,57 +116,51 @@ struct linux_xfrm_mib {
         unsigned long   mibs[LINUX_MIB_XFRMMAX];
 };
 
-/* 
- * FIXME: On x86 and some other CPUs the split into user and softirq parts
- * is not needed because addl $1,memory is atomic against interrupts (but 
- * atomic_inc would be overkill because of the lock cycles). Wants new 
- * nonlocked_atomic_inc() primitives -AK
- */ 
+#define SNMP_ARRAY_SZ 1
+
 #define DEFINE_SNMP_STAT(type, name)    \
-        __typeof__(type) __percpu *name[2]
+        __typeof__(type) __percpu *name[SNMP_ARRAY_SZ]
 #define DEFINE_SNMP_STAT_ATOMIC(type, name)     \
         __typeof__(type) *name
 #define DECLARE_SNMP_STAT(type, name)   \
-        extern __typeof__(type) __percpu *name[2]
-
-#define SNMP_STAT_BHPTR(name)   (name[0])
-#define SNMP_STAT_USRPTR(name)  (name[1])
+        extern __typeof__(type) __percpu *name[SNMP_ARRAY_SZ]
 
 #define SNMP_INC_STATS_BH(mib, field)   \
                         __this_cpu_inc(mib[0]->mibs[field])
+
 #define SNMP_INC_STATS_USER(mib, field) \
-                        this_cpu_inc(mib[1]->mibs[field])
+                        irqsafe_cpu_inc(mib[0]->mibs[field])
+
 #define SNMP_INC_STATS_ATOMIC_LONG(mib, field)  \
                         atomic_long_inc(&mib->mibs[field])
+
 #define SNMP_INC_STATS(mib, field)      \
-                        this_cpu_inc(mib[!in_softirq()]->mibs[field])
+                        irqsafe_cpu_inc(mib[0]->mibs[field])
+
 #define SNMP_DEC_STATS(mib, field)      \
-                        this_cpu_dec(mib[!in_softirq()]->mibs[field])
+                        irqsafe_cpu_dec(mib[0]->mibs[field])
+
 #define SNMP_ADD_STATS_BH(mib, field, addend)   \
                         __this_cpu_add(mib[0]->mibs[field], addend)
+
 #define SNMP_ADD_STATS_USER(mib, field, addend) \
-                        this_cpu_add(mib[1]->mibs[field], addend)
+                        irqsafe_cpu_add(mib[0]->mibs[field], addend)
+
 #define SNMP_ADD_STATS(mib, field, addend)      \
-                        this_cpu_add(mib[!in_softirq()]->mibs[field], addend)
+                        irqsafe_cpu_add(mib[0]->mibs[field], addend)
 /*
  * Use "__typeof__(*mib[0]) *ptr" instead of "__typeof__(mib[0]) ptr"
  * to make @ptr a non-percpu pointer.
  */
 #define SNMP_UPD_PO_STATS(mib, basefield, addend)       \
         do { \
-                __typeof__(*mib[0]) *ptr; \
-                preempt_disable(); \
-                ptr = this_cpu_ptr((mib)[!in_softirq()]); \
-                ptr->mibs[basefield##PKTS]++; \
-                ptr->mibs[basefield##OCTETS] += addend;\
-                preempt_enable(); \
+                irqsafe_cpu_inc(mib[0]->mibs[basefield##PKTS]);         \
+                irqsafe_cpu_add(mib[0]->mibs[basefield##OCTETS], addend);       \
         } while (0)
 #define SNMP_UPD_PO_STATS_BH(mib, basefield, addend)    \
         do { \
-                __typeof__(*mib[0]) *ptr = \
-                        __this_cpu_ptr((mib)[0]); \
-                ptr->mibs[basefield##PKTS]++; \
-                ptr->mibs[basefield##OCTETS] += addend;\
+                __this_cpu_inc(mib[0]->mibs[basefield##PKTS]);          \
+                __this_cpu_add(mib[0]->mibs[basefield##OCTETS], addend);        \
         } while (0)
 
 
@@ -179,40 +173,20 @@ struct linux_xfrm_mib {
                 ptr->mibs[field] += addend;                             \
                 u64_stats_update_end(&ptr->syncp);                      \
         } while (0)
+
 #define SNMP_ADD_STATS64_USER(mib, field, addend)                       \
         do {                                                            \
-                __typeof__(*mib[0]) *ptr;                               \
-                preempt_disable();                                      \
-                ptr = __this_cpu_ptr((mib)[1]);                         \
-                u64_stats_update_begin(&ptr->syncp);                    \
-                ptr->mibs[field] += addend;                             \
-                u64_stats_update_end(&ptr->syncp);                      \
-                preempt_enable();                                       \
+                local_bh_disable();                                     \
+                SNMP_ADD_STATS64_BH(mib, field, addend);                \
+                local_bh_enable();                                      \
         } while (0)
+
 #define SNMP_ADD_STATS64(mib, field, addend)                            \
-        do {                                                            \
-                __typeof__(*mib[0]) *ptr;                               \
-                preempt_disable();                                      \
-                ptr = __this_cpu_ptr((mib)[!in_softirq()]);             \
-                u64_stats_update_begin(&ptr->syncp);                    \
-                ptr->mibs[field] += addend;                             \
-                u64_stats_update_end(&ptr->syncp);                      \
-                preempt_enable();                                       \
-        } while (0)
+                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(mib, basefield, addend)                     \
-        do {                                                            \
-                __typeof__(*mib[0]) *ptr;                               \
-                preempt_disable();                                      \
-                ptr = __this_cpu_ptr((mib)[!in_softirq()]);             \
-                u64_stats_update_begin(&ptr->syncp);                    \
-                ptr->mibs[basefield##PKTS]++;                           \
-                ptr->mibs[basefield##OCTETS] += addend;                 \
-                u64_stats_update_end(&ptr->syncp);                      \
-                preempt_enable();                                       \
-        } while (0)
 #define SNMP_UPD_PO_STATS64_BH(mib, basefield, addend)                  \
         do {                                                            \
                 __typeof__(*mib[0]) *ptr;                               \
@@ -222,6 +196,12 @@ struct linux_xfrm_mib {
                 ptr->mibs[basefield##OCTETS] += addend;                 \
                 u64_stats_update_end(&ptr->syncp);                      \
         } while (0)
+#define SNMP_UPD_PO_STATS64(mib, basefield, addend)                     \
+        do {                                                            \
+                local_bh_disable();                                     \
+                SNMP_UPD_PO_STATS64_BH(mib, basefield, addend);         \
+                local_bh_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)
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 9c1926027a26..83673d23d4dd 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1437,11 +1437,11 @@ EXPORT_SYMBOL_GPL(inet_ctl_sock_create);
 unsigned long snmp_fold_field(void __percpu *mib[], int offt)
 {
         unsigned long res = 0;
-        int i;
+        int i, j;
 
         for_each_possible_cpu(i) {
-                res += *(((unsigned long *) per_cpu_ptr(mib[0], i)) + offt);
-                res += *(((unsigned long *) per_cpu_ptr(mib[1], i)) + offt);
+                for (j = 0; j < SNMP_ARRAY_SZ; j++)
+                        res += *(((unsigned long *) per_cpu_ptr(mib[j], i)) + offt);
         }
         return res;
 }
@@ -1455,28 +1455,19 @@ u64 snmp_fold_field64(void __percpu *mib[], int offt, size_t syncp_offset)
         int cpu;
 
         for_each_possible_cpu(cpu) {
-                void *bhptr, *userptr;
+                void *bhptr;
                 struct u64_stats_sync *syncp;
-                u64 v_bh, v_user;
+                u64 v;
                 unsigned int start;
 
-                /* first mib used by softirq context, we must use _bh() accessors */
-                bhptr = per_cpu_ptr(SNMP_STAT_BHPTR(mib), cpu);
+                bhptr = per_cpu_ptr(mib[0], cpu);
                 syncp = (struct u64_stats_sync *)(bhptr + syncp_offset);
                 do {
                         start = u64_stats_fetch_begin_bh(syncp);
-                        v_bh = *(((u64 *) bhptr) + offt);
+                        v = *(((u64 *) bhptr) + offt);
                 } while (u64_stats_fetch_retry_bh(syncp, start));
 
-                /* second mib used in USER context */
-                userptr = per_cpu_ptr(SNMP_STAT_USRPTR(mib), cpu);
-                syncp = (struct u64_stats_sync *)(userptr + syncp_offset);
-                do {
-                        start = u64_stats_fetch_begin(syncp);
-                        v_user = *(((u64 *) userptr) + offt);
-                } while (u64_stats_fetch_retry(syncp, start));
-
-                res += v_bh + v_user;
+                res += v;
         }
         return res;
 }
@@ -1488,25 +1479,28 @@ int snmp_mib_init(void __percpu *ptr[2], size_t mibsize, size_t align)
         BUG_ON(ptr == NULL);
         ptr[0] = __alloc_percpu(mibsize, align);
         if (!ptr[0])
-                goto err0;
+                return -ENOMEM;
+#if SNMP_ARRAY_SZ == 2
         ptr[1] = __alloc_percpu(mibsize, align);
-        if (!ptr[1])
-                goto err1;
+        if (!ptr[1]) {
+                free_percpu(ptr[0]);
+                ptr[0] = NULL;
+                return -ENOMEM;
+        }
+#endif
         return 0;
-err1:
-        free_percpu(ptr[0]);
-        ptr[0] = NULL;
-err0:
-        return -ENOMEM;
 }
 EXPORT_SYMBOL_GPL(snmp_mib_init);
 
-void snmp_mib_free(void __percpu *ptr[2])
+void snmp_mib_free(void __percpu *ptr[SNMP_ARRAY_SZ])
 {
+        int i;
+
         BUG_ON(ptr == NULL);
-        free_percpu(ptr[0]);
-        free_percpu(ptr[1]);
-        ptr[0] = ptr[1] = NULL;
+        for (i = 0; i < SNMP_ARRAY_SZ; i++) {
+                free_percpu(ptr[i]);
+                ptr[i] = NULL;
+        }
 }
 EXPORT_SYMBOL_GPL(snmp_mib_free);