diff options
| author | Juergen Gross <jgross@suse.com> | 2017-01-10 14:32:52 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-11-15 15:53:11 +0100 |
| commit | a1644f9c78e401b985923e13f866b397b8a787a0 (patch) | |
| tree | 696db6f2b3693b90c215190124287b056ca07345 /drivers/net | |
| parent | 6da1c989cccef3f5268dc634b9adf39d80a4b4e9 (diff) | |
xen/netback: set default upper limit of tx/rx queues to 8
[ Upstream commit 56dd5af9bc23d0d5d23bb207c477715b4c2216c5 ]
The default for the maximum number of tx/rx queues of one interface is
the number of cpus of the system today. As each queue pair reserves 512
grant pages this default consumes a ridiculous number of grants for
large guests.
Limit the queue number to 8 as default. This value can be modified
via a module parameter if required.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/xen-netback/netback.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index d9b5b73c35a0..a7bdb1ffac2e 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -67,6 +67,7 @@ module_param(rx_drain_timeout_msecs, uint, 0444); unsigned int rx_stall_timeout_msecs = 60000; module_param(rx_stall_timeout_msecs, uint, 0444); +#define MAX_QUEUES_DEFAULT 8 unsigned int xenvif_max_queues; module_param_named(max_queues, xenvif_max_queues, uint, 0644); MODULE_PARM_DESC(max_queues, @@ -1626,11 +1627,12 @@ static int __init netback_init(void) if (!xen_domain()) return -ENODEV; - /* Allow as many queues as there are CPUs if user has not + /* Allow as many queues as there are CPUs but max. 8 if user has not * specified a value. */ if (xenvif_max_queues == 0) - xenvif_max_queues = num_online_cpus(); + xenvif_max_queues = min_t(unsigned int, MAX_QUEUES_DEFAULT, + num_online_cpus()); if (fatal_skb_slots < XEN_NETBK_LEGACY_SLOTS_MAX) { pr_info("fatal_skb_slots too small (%d), bump it to XEN_NETBK_LEGACY_SLOTS_MAX (%d)\n", |