From b65f164d37cf6d4aac59b0e13c2e5c4cfe293fd2 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Thu, 19 Oct 2017 09:31:43 +0200 Subject: [PATCH] ipv6: let trace_fib6_table_lookup() dereference the fib table The perf traces for ipv6 routing code show a relevant cost around trace_fib6_table_lookup(), even if no trace is enabled. This is due to the fib6_table de-referencing currently performed by the caller. Let's the tracing code pay this overhead, passing to the trace helper the table pointer. This gives small but measurable performance improvement under UDP flood. Signed-off-by: Paolo Abeni Acked-by: Steven Rostedt (VMware) Acked-by: David Ahern Acked-by: Martin KaFai Lau Signed-off-by: David S. Miller --- include/trace/events/fib6.h | 6 +++--- net/ipv6/route.c | 12 ++++++------ 2 files changed, 9 insertions(+), 9 deletions(-) diff --git a/include/trace/events/fib6.h b/include/trace/events/fib6.h index d60096cddb2a..b34bed17abc7 100644 --- a/include/trace/events/fib6.h +++ b/include/trace/events/fib6.h @@ -12,9 +12,9 @@ TRACE_EVENT(fib6_table_lookup, TP_PROTO(const struct net *net, const struct rt6_info *rt, - u32 tb_id, const struct flowi6 *flp), + struct fib6_table *table, const struct flowi6 *flp), - TP_ARGS(net, rt, tb_id, flp), + TP_ARGS(net, rt, table, flp), TP_STRUCT__entry( __field( u32, tb_id ) @@ -34,7 +34,7 @@ TRACE_EVENT(fib6_table_lookup, TP_fast_assign( struct in6_addr *in6; - __entry->tb_id = tb_id; + __entry->tb_id = table->tb6_id; __entry->oif = flp->flowi6_oif; __entry->iif = flp->flowi6_iif; __entry->tos = ip6_tclass(flp->flowlabel); diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 074fac966018..46c59a53c53f 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -945,7 +945,7 @@ restart: rcu_read_unlock(); - trace_fib6_table_lookup(net, rt, table->tb6_id, fl6); + trace_fib6_table_lookup(net, rt, table, fl6); return rt; @@ -1682,7 +1682,7 @@ redo_rt6_select: if (rt == net->ipv6.ip6_null_entry) { rcu_read_unlock(); dst_hold(&rt->dst); - trace_fib6_table_lookup(net, rt, table->tb6_id, fl6); + trace_fib6_table_lookup(net, rt, table, fl6); return rt; } else if (rt->rt6i_flags & RTF_CACHE) { if (ip6_hold_safe(net, &rt, true)) { @@ -1690,7 +1690,7 @@ redo_rt6_select: rt6_dst_from_metrics_check(rt); } rcu_read_unlock(); - trace_fib6_table_lookup(net, rt, table->tb6_id, fl6); + trace_fib6_table_lookup(net, rt, table, fl6); return rt; } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) && !(rt->rt6i_flags & RTF_GATEWAY))) { @@ -1726,7 +1726,7 @@ redo_rt6_select: } uncached_rt_out: - trace_fib6_table_lookup(net, uncached_rt, table->tb6_id, fl6); + trace_fib6_table_lookup(net, uncached_rt, table, fl6); return uncached_rt; } else { @@ -1754,7 +1754,7 @@ uncached_rt_out: } local_bh_enable(); rcu_read_unlock(); - trace_fib6_table_lookup(net, pcpu_rt, table->tb6_id, fl6); + trace_fib6_table_lookup(net, pcpu_rt, table, fl6); return pcpu_rt; } } @@ -2195,7 +2195,7 @@ out: rcu_read_unlock(); - trace_fib6_table_lookup(net, rt, table->tb6_id, fl6); + trace_fib6_table_lookup(net, rt, table, fl6); return rt; };