@@ -317,18 +317,12 @@ static int kobject_uevent_net_broadcast(struct kobject *kobj,
skb = alloc_skb(len + env->buflen, GFP_KERNEL);
if (skb) {
char *scratch;
- int i;
/* add header */
scratch = skb_put(skb, len);
sprintf(scratch, "%s@%s", action_string, devpath);
- /* copy keys to our continuous event payload buffer */
- for (i = 0; i < env->envp_idx; i++) {
- len = strlen(env->envp[i]) + 1;
- scratch = skb_put(skb, len);
- strcpy(scratch, env->envp[i]);
- }
+ skb_put_data(skb, env->buf, env->buflen);
NETLINK_CB(skb).dst_group = 1;
retval = netlink_broadcast_filtered(uevent_sock, skb,
No need to iterate over strings, just copy in one efficient memcpy() call. Tested: time perf record "(for f in `seq 1 3000` ; do ip netns add tast$f; done)" [ perf record: Woken up 10 times to write data ] [ perf record: Captured and wrote 8.224 MB perf.data (~359301 samples) ] real 0m52.554s # instead of 1m7.492s user 0m0.309s sys 0m51.375s # instead of 1m6.875s 9.88% ip [kernel.kallsyms] [k] netlink_broadcast_filtered 8.86% ip [kernel.kallsyms] [k] string 7.37% ip [kernel.kallsyms] [k] __ip6addrlbl_add 5.68% ip [kernel.kallsyms] [k] netlink_has_listeners 5.52% ip [kernel.kallsyms] [k] memcpy_erms 4.76% ip [kernel.kallsyms] [k] __alloc_skb 4.54% ip [kernel.kallsyms] [k] vsnprintf 3.94% ip [kernel.kallsyms] [k] format_decode 3.80% ip [kernel.kallsyms] [k] kmem_cache_alloc_node_trace 3.71% ip [kernel.kallsyms] [k] kmem_cache_alloc_node 3.66% ip [kernel.kallsyms] [k] kobject_uevent_env 3.38% ip [kernel.kallsyms] [k] strlen 2.65% ip [kernel.kallsyms] [k] _raw_spin_lock_irqsave 2.20% ip [kernel.kallsyms] [k] kfree 2.09% ip [kernel.kallsyms] [k] memset_erms 2.07% ip [kernel.kallsyms] [k] ___cache_free 1.95% ip [kernel.kallsyms] [k] kmem_cache_free 1.91% ip [kernel.kallsyms] [k] _raw_read_lock 1.45% ip [kernel.kallsyms] [k] ksize 1.25% ip [kernel.kallsyms] [k] _raw_spin_unlock_irqrestore 1.00% ip [kernel.kallsyms] [k] widen_string Signed-off-by: Eric Dumazet <edumazet@google.com> --- lib/kobject_uevent.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-)