inet: frag: remove periodic secret rebuild timer

merge functionality into the eviction workqueue.

Instead of rebuilding every n seconds, take advantage of the upper
hash chain length limit.

If we hit it, mark table for rebuild and schedule workqueue.
To prevent frequent rebuilds when we're completely overloaded,
don't rebuild more than once every 5 seconds.

ipfrag_secret_interval sysctl is now obsolete and has been marked as
deprecated, it still can be changed so scripts won't be broken but it
won't have any effect. A comment is left above each unused secret_timer
variable to avoid confusion.

Joint work with Nikolay Aleksandrov.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 10 deletions

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 625c8dda4be7..e8c304e37831 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -111,11 +111,6 @@ ipfrag_low_thresh - INTEGER
 ipfrag_time - INTEGER
         Time in seconds to keep an IP fragment in memory.
 
-ipfrag_secret_interval - INTEGER
-        Regeneration interval (in seconds) of the hash secret (or lifetime
-        for the hash secret) for IP fragments.
-        Default: 600
-
 ipfrag_max_dist - INTEGER
         ipfrag_max_dist is a non-negative integer value which defines the
         maximum "disorder" which is allowed among fragments which share a
@@ -1164,11 +1159,6 @@ ip6frag_low_thresh - INTEGER
 ip6frag_time - INTEGER
         Time in seconds to keep an IPv6 fragment in memory.
 
-ip6frag_secret_interval - INTEGER
-        Regeneration interval (in seconds) of the hash secret (or lifetime
-        for the hash secret) for IPv6 fragments.
-        Default: 600
-
 conf/default/*:
         Change the interface-specific default settings.