> > On 08/20/2014 07:17 PM, Michael S. Tsirkin wrote: > > On Wed, Aug 20, 2014 at 12:58:17PM +0200, Jiri Pirko wrote: > >> > Mon, Aug 18, 2014 at 03:37:18PM CEST, [email protected] wrote: > >>> > > This patch publishes maximum number of tun/tap queues allocated as a > >>> > > read_only module parameter which a user space application like > >>> > > libvirt > >>> > > can make use of to limit maximum number of queues. Value of read_only > >>> > > module parameter can be writable only at module load time. If no > >>> > > value is set > >>> > > at module load time a default value 256 is used which is equal to > >>> > > maximum number > >>> > > of vCPUS allowed by KVM. > >>> > > > >>> > > Administrator can specify maximum number of queues only at the driver > >>> > > module load time. > >>> > > > >>> > >Signed-off-by: Pankaj Gupta <[email protected]> > >>> > >--- > >>> > > drivers/net/tun.c | 13 +++++++++++-- > >>> > > 1 files changed, 11 insertions(+), 2 deletions(-) > >>> > > > >>> > >diff --git a/drivers/net/tun.c b/drivers/net/tun.c > >>> > >index acaaf67..1f518e2 100644 > >>> > >--- a/drivers/net/tun.c > >>> > >+++ b/drivers/net/tun.c > >>> > >@@ -119,6 +119,9 @@ struct tap_filter { > >>> > > > >>> > > #define TUN_FLOW_EXPIRE (3 * HZ) > >>> > > > >>> > >+static int max_tap_queues = MAX_TAP_QUEUES; > >>> > >+module_param(max_tap_queues, int, S_IRUGO); > >> > > >> > Please do not introduce new module paramaters. Please other ways to > >> > interchange values with userspace. > > I suggested this initially, but thinking more about it, I agree. > > > > It's a global limit (necessary to limit memory utilization by > > userspace), but it should be possible to change it > > after module load. > > How about pass this limit through ifr during TUNSETIFF, then > alloc_netdev_mq() can use this limit.
Any other ideas/comments from the experts. Or shall I re-repost other patches in the series except this patch until we agree on one. > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
