inet: frags: remove INET_FRAG_EVICTED and use list_evictor for the test

We can simply remove the INET_FRAG_EVICTED flag to avoid all the flags
race conditions with the evictor and use a participation test for the
evictor list, when we're at that point (after inet_frag_kill) in the
timer there're 2 possible cases:

1. The evictor added the entry to its evictor list while the timer was
waiting for the chainlock
or
2. The timer unchained the entry and the evictor won't see it

In both cases we should be able to see list_evictor correctly due
to the sync on the chainlock.

Joint work with Florian Westphal.

Tested-by: Frank Schreuder <fschreuder@transip.nl>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Nikolay Aleksandrov
2015-07-23 12:05:40 +02:00
committed by David S. Miller
parent 5719b296fb
commit caaecdd3d3
4 changed files with 7 additions and 5 deletions

View File

@@ -202,7 +202,7 @@ static void ip_expire(unsigned long arg)
ipq_kill(qp);
IP_INC_STATS_BH(net, IPSTATS_MIB_REASMFAILS);
if (!(qp->q.flags & INET_FRAG_EVICTED)) {
if (!inet_frag_evicting(&qp->q)) {
struct sk_buff *head = qp->q.fragments;
const struct iphdr *iph;
int err;