From fca8300f68fe3fbb2fcda862f0f114011715b3bc Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" Date: Mon, 4 Jul 2022 09:14:36 -0400 Subject: tracing/ipv4/ipv6: Use static array for name field in fib*_lookup_table event The fib_lookup_table and fib6_lookup_table events declare name as a dynamic_array, but also give it a fixed size, which defeats the purpose of the dynamic array, especially since the dynamic array also includes meta data in the event to specify its size. Since the size of the name is at most 16 bytes (defined by IFNAMSIZ), it is not worth spending the effort to determine the size of the string. Just use a fixed size array and copy into it. This will save 4 bytes that are used for the meta data that saves the size and position of a dynamic array, and even slightly speed up the event processing. Link: https://lkml.kernel.org/r/20220704091436.3705edbf@rorschach.local.home Cc: David S. Miller Cc: netdev@vger.kernel.org Acked-by: Jakub Kicinski Reviewed-by: David Ahern Signed-off-by: Steven Rostedt (Google) --- include/trace/events/fib6.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'include/trace/events/fib6.h') diff --git a/include/trace/events/fib6.h b/include/trace/events/fib6.h index c6abdcc77c12..6e821eb79450 100644 --- a/include/trace/events/fib6.h +++ b/include/trace/events/fib6.h @@ -31,7 +31,7 @@ TRACE_EVENT(fib6_table_lookup, __field( u16, dport ) __field( u8, proto ) __field( u8, rt_type ) - __dynamic_array( char, name, IFNAMSIZ ) + __array( char, name, IFNAMSIZ ) __array( __u8, gw, 16 ) ), @@ -63,9 +63,9 @@ TRACE_EVENT(fib6_table_lookup, } if (res->nh && res->nh->fib_nh_dev) { - __assign_str(name, res->nh->fib_nh_dev); + strlcpy(__entry->name, res->nh->fib_nh_dev->name, IFNAMSIZ); } else { - __assign_str(name, "-"); + strcpy(__entry->name, "-"); } if (res->f6i == net->ipv6.fib6_null_entry) { struct in6_addr in6_zero = {}; @@ -83,7 +83,7 @@ TRACE_EVENT(fib6_table_lookup, __entry->tb_id, __entry->oif, __entry->iif, __entry->proto, __entry->src, __entry->sport, __entry->dst, __entry->dport, __entry->tos, __entry->scope, __entry->flags, - __get_str(name), __entry->gw, __entry->err) + __entry->name, __entry->gw, __entry->err) ); #endif /* _TRACE_FIB6_H */ -- cgit v1.2.3-59-g8ed1b