From: Florian Westphal <fw@xxxxxxxxx>
This helper is inlined, so keep it as small as possible.
If the static key is true, there is only a very small chance
that info->trace is false:
1. tracing was enabled at this very moment, the static key was
updated to active right after nft_do_table was called.
2. tracing was disabled at this very moment.
trace->info is already false, the static key is about to
be patched to false soon.
In both cases, no event will be sent because info->trace
is false (checked in noinline slowpath). info->nf_trace is irrelevant.
The nf_trace update is redunant in this case, but this will only
happen for short duration, when static key flips.
text data bss dec hex filename
old: 2980 192 32 3204 c84 nf_tables_core.o
new: 2964 192 32 3188 c74i nf_tables_core.o
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
net/netfilter/nf_tables_core.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/net/netfilter/nf_tables_core.c b/net/netfilter/nf_tables_core.c
index 89c05b64c2a2..bed855638050 100644
--- a/net/netfilter/nf_tables_core.c
+++ b/net/netfilter/nf_tables_core.c
@@ -67,10 +67,8 @@ static inline void nft_trace_packet(const struct nft_pktinfo *pkt,
static inline void nft_trace_copy_nftrace(const struct nft_pktinfo *pkt,
struct nft_traceinfo *info)
{
- if (static_branch_unlikely(&nft_trace_enabled)) {
- if (info->trace)
- info->nf_trace = pkt->skb->nf_trace;
- }
+ if (static_branch_unlikely(&nft_trace_enabled))
+ info->nf_trace = pkt->skb->nf_trace;
}
static void nft_bitwise_fast_eval(const struct nft_expr *expr,
--
2.30.2
