Commit be916cde authored by Jarek Poplawski's avatar Jarek Poplawski Committed by David S. Miller
Browse files

ipv4: Fix inflate_threshold_root automatically

During large updates there could be triggered warnings like: "Fix
inflate_threshold_root. Now=25 size=11 bits" if inflate() of the root
node isn't finished in 10 loops. It should be much rarer now, after
changing the threshold from 15 to 25, and a temporary problem, so
this patch tries to handle it automatically using a fix variable to
increase by one inflate threshold for next root resizes (up to the 35
limit, max fix = 10). The fix variable is decreased when root's
inflate() finishes below 7 loops (even if some other, smaller table/
trie is updated -- for simplicity the fix variable is global for now).
Reported-by: default avatarPawel Staszewski <>
Reported-by: default avatarJorge Boncompte [DTI2] <>
Tested-by: default avatarPawel Staszewski <>
Signed-off-by: default avatarJarek Poplawski <>
Signed-off-by: default avatarRobert Olsson <>
Signed-off-by: default avatarDavid S. Miller <>
parent c3059477
......@@ -327,6 +327,8 @@ static const int inflate_threshold = 50;
static const int halve_threshold_root = 15;
static const int inflate_threshold_root = 25;
static int inflate_threshold_root_fix;
#define INFLATE_FIX_MAX 10 /* a comment in resize() */
static void __alias_free_mem(struct rcu_head *head)
......@@ -617,7 +619,8 @@ static struct node *resize(struct trie *t, struct tnode *tn)
/* Keep root node larger */
if (!tn->parent)
inflate_threshold_use = inflate_threshold_root;
inflate_threshold_use = inflate_threshold_root +
inflate_threshold_use = inflate_threshold;
......@@ -641,15 +644,27 @@ static struct node *resize(struct trie *t, struct tnode *tn)
if (max_resize < 0) {
if (!tn->parent)
pr_warning("Fix inflate_threshold_root."
" Now=%d size=%d bits\n",
inflate_threshold_root, tn->bits);
if (!tn->parent) {
* It was observed that during large updates even
* inflate_threshold_root = 35 might be needed to avoid
* this warning; but it should be temporary, so let's
* try to handle this automatically.
if (inflate_threshold_root_fix < INFLATE_FIX_MAX)
pr_warning("Fix inflate_threshold_root."
" Now=%d size=%d bits fix=%d\n",
inflate_threshold_root, tn->bits,
} else {
pr_warning("Fix inflate_threshold."
" Now=%d size=%d bits\n",
inflate_threshold, tn->bits);
} else if (max_resize > 3 && !tn->parent && inflate_threshold_root_fix)
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