tjh.dev / kernel
Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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net: avoid reloads in SNMP_UPD_PO_STATS

Avoid two instructions to reload dev->nd_net->mib.ip_statistics pointer,
unsing a temp variable, in ip_rcv(), ip_output() paths for example.

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

authored by

Eric Dumazet and committed by
David S. Miller d25398df 9eb43e76

+6 -4
+6 -4
include/net/snmp.h
··· 154 154 */ 155 155 #define SNMP_UPD_PO_STATS(mib, basefield, addend) \ 156 156 do { \ 157 - this_cpu_inc(mib[0]->mibs[basefield##PKTS]); \ 158 - this_cpu_add(mib[0]->mibs[basefield##OCTETS], addend); \ 157 + __typeof__(*mib[0]->mibs) *ptr = mib[0]->mibs; \ 158 + this_cpu_inc(ptr[basefield##PKTS]); \ 159 + this_cpu_add(ptr[basefield##OCTETS], addend); \ 159 160 } while (0) 160 161 #define SNMP_UPD_PO_STATS_BH(mib, basefield, addend) \ 161 162 do { \ 162 - __this_cpu_inc(mib[0]->mibs[basefield##PKTS]); \ 163 - __this_cpu_add(mib[0]->mibs[basefield##OCTETS], addend); \ 163 + __typeof__(*mib[0]->mibs) *ptr = mib[0]->mibs; \ 164 + __this_cpu_inc(ptr[basefield##PKTS]); \ 165 + __this_cpu_add(ptr[basefield##OCTETS], addend); \ 164 166 } while (0) 165 167 166 168