| Message ID | 20220704091436.3705edbf@rorschach.local.home (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | [v2] tracing/ipv4/ipv6: Use static array for name field in fib*_lookup_table event | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On 7/4/22 7:14 AM, Steven Rostedt wrote: > From: "Steven Rostedt (Google)" <rostedt@goodmis.org> > > 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. > > Cc: David Ahern <dsahern@gmail.com> > Cc: David S. Miller <davem@davemloft.net> > Cc: netdev@vger.kernel.org > Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> > --- > Changes since v1: https://lkml.kernel.org/r/20220703102359.30f12e39@rorschach.local.home > - Just use a fixed size array instead of calculating the > size needed for the dynamic allocation. > > include/trace/events/fib.h | 6 +++--- > include/trace/events/fib6.h | 8 ++++---- > 2 files changed, 7 insertions(+), 7 deletions(-) > Reviewed-by: David Ahern <dsahern@kernel.org>
On Mon, 4 Jul 2022 13:09:01 -0600 David Ahern <dsahern@gmail.com> wrote: > > include/trace/events/fib.h | 6 +++--- > > include/trace/events/fib6.h | 8 ++++---- > > 2 files changed, 7 insertions(+), 7 deletions(-) > > > > Reviewed-by: David Ahern <dsahern@kernel.org> > Is everyone OK if I take this through my tree then? I'm fine if it goes through net-next too. -- Steve
On Tue, 5 Jul 2022 10:00:41 -0400 Steven Rostedt wrote: > On Mon, 4 Jul 2022 13:09:01 -0600 > David Ahern <dsahern@gmail.com> wrote: > > > > include/trace/events/fib.h | 6 +++--- > > > include/trace/events/fib6.h | 8 ++++---- > > > 2 files changed, 7 insertions(+), 7 deletions(-) > > > > > > > Reviewed-by: David Ahern <dsahern@kernel.org> > > > > Is everyone OK if I take this through my tree then? > > I'm fine if it goes through net-next too. Slight risk of conflicts there if someone decides to add another FIB trace point, but seems unlikely so feel free to take it: Acked-by: Jakub Kicinski <kuba@kernel.org>
diff --git a/include/trace/events/fib.h b/include/trace/events/fib.h index 6f2a4dc35e37..c2300c407f58 100644 --- a/include/trace/events/fib.h +++ b/include/trace/events/fib.h @@ -32,7 +32,7 @@ TRACE_EVENT(fib_table_lookup, __array( __u8, gw6, 16 ) __field( u16, sport ) __field( u16, dport ) - __dynamic_array(char, name, IFNAMSIZ ) + __array(char, name, IFNAMSIZ ) ), TP_fast_assign( @@ -66,7 +66,7 @@ TRACE_EVENT(fib_table_lookup, } dev = nhc ? nhc->nhc_dev : NULL; - __assign_str(name, dev ? dev->name : "-"); + strlcpy(__entry->name, dev ? dev->name : "-", IFNAMSIZ); if (nhc) { if (nhc->nhc_gw_family == AF_INET) { @@ -95,7 +95,7 @@ TRACE_EVENT(fib_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->gw4, __entry->gw6, __entry->err) + __entry->name, __entry->gw4, __entry->gw6, __entry->err) ); #endif /* _TRACE_FIB_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 */