lkml.org 
[lkml]   [2018]   [Jul]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v1 3/3] net: WireGuard secure network tunnel
On Tue, 31 Jul 2018 21:11:02 +0200
"Jason A. Donenfeld" <Jason@zx2c4.com> wrote:

> +#define push(stack, p, len) ({ \
> + if (rcu_access_pointer(p)) { \
> + BUG_ON(len >= 128); \
> + stack[len++] = rcu_dereference_protected(p, lockdep_is_held(lock)); \
> + } \
> + true; \
> +})
> +static void free_root_node(struct allowedips_node __rcu *top, struct mutex *lock)
> +{
> + struct allowedips_node *stack[128], *node;
> + unsigned int len;
> +
> + for (len = 0, push(stack, top, len); len > 0 && (node = stack[--len]) && push(stack, node->bit[0], len) && push(stack, node->bit[1], len);)
> + call_rcu_bh(&node->rcu, node_free_rcu);
> +}

This looks like you are doing traversal to free a tree. The stack is there so that you do the rcu callbacks
in the proper order. Won't this create an lot of RCU work at once?

\
 
 \ /
  Last update: 2018-07-31 22:27    [W:0.147 / U:0.552 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site