Commit Graph

7 Commits

Author SHA1 Message Date
Herbert Xu 48d83325b6 [NET]: Prevent multiple qdisc runs
Having two or more qdisc_run's contend against each other is bad because
it can induce packet reordering if the packets have to be requeued.  It
appears that this is an unintended consequence of relinquinshing the queue
lock while transmitting.  That in turn is needed for devices that spend a
lot of time in their transmit routine.

There are no advantages to be had as devices with queues are inherently
single-threaded (the loopback device is not but then it doesn't have a
queue).

Even if you were to add a queue to a parallel virtual device (e.g., bolt
a tbf filter in front of an ipip tunnel device), you would still want to
process the queue in sequence to ensure that the packets are ordered
correctly.

The solution here is to steal a bit from net_device to prevent this.

BTW, as qdisc_restart is no longer used by anyone as a module inside the
kernel (IIRC it used to with netif_wake_queue), I have not exported the
new __qdisc_run function.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-19 23:57:59 -07:00
Patrick McHardy 538e43a4bd [PKT_SCHED]: Use USEC_PER_SEC
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-09 14:16:05 -08:00
Thomas Graf 3d54b82fdf [PKT_SCHED]: Cleanup qdisc creation and alignment macros
Adds qdisc_alloc() to share code between qdisc_create()
and qdisc_create_dflt(). Hides the qdisc alignment behind
macros and makes use of them.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:15:09 -07:00
Thomas Graf e41a33e6ec [PKT_SCHED]: Move sch_generic.c prototypes to correct header file
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:14:30 -07:00
Patrick McHardy 9dfa277f88 [PKT_SCHED]: Fix range in PSCHED_TDIFF_SAFE to 0..bound
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-03 14:41:18 -07:00
Nicolas Dichtel 7b3c63ac7c [PKT_SCHED]: Fix range in psched_tod_diff() to 0..bound
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-28 12:14:37 -07:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00