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. -- 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/
