aoe: failover remote interface based on aoe_deadsecs parameter
The aoe_deadsecs module parameter allows the user to specify a hard limit
on the number of seconds an AoE command can be retransmitted before the
AoE block device is considered to have failed.
Using aoe_deadsecs to determine the time we try using a different remote
interface helps to ensure that the hard limit is not reached before we've
tried to recover by sending to a different remote port.
As a data storage target, the AoE target is unambiguously identified by
its {major, minor} AoE address tuple, and an AoE target can have multiple
MAC addresses. However, note that "target" in the driver code and
comments means a {major, minor, MAC address} tuple, as in "somewhere to
send packets".
Signed-off-by: Ed Cashin <ecashin@coraid.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/block/aoe/aoe.h b/drivers/block/aoe/aoe.h
index ffded64..d17b727 100644
--- a/drivers/block/aoe/aoe.h
+++ b/drivers/block/aoe/aoe.h
@@ -96,7 +96,6 @@
TIMERTICK = HZ / 10,
MINTIMER = HZ >> 2,
MAXTIMER = HZ << 1,
- HELPWAIT = 20,
};
struct buf {
diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index bbab40c..e3291df 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -633,11 +633,9 @@
list_del(pos);
t = f->t;
- if (n > HELPWAIT) {
- /* see if another target can help */
- if (d->ntargets > 1)
- d->htgt = t;
- }
+ if (n > aoe_deadsecs/2)
+ d->htgt = t; /* see if another target can help */
+
if (t->nout == t->maxout) {
if (t->maxout > 1)
t->maxout--;