On Fri, Oct 17, 2025 at 07:03:31AM +0200, Przemek Kitszel wrote: > On 10/16/25 17:36, Alexander Lobakin wrote: > > From: Michal Swiatkowski <[email protected]> > > Date: Thu, 16 Oct 2025 08:22:50 +0200 > > > > > On some high-core systems loading ice driver with default values can > > > lead to queue/irq exhaustion. It will result in no additional resources > > > for SR-IOV. > > > > > > In most cases there is no performance reason for more than 64 queues. > > > Limit the default value to 64. Still, using ethtool the number of > > > queues can be changed up to num_online_cpus(). > > > > > > This change affects only the default queue amount on systems with more > > > than 64 cores. > > > > > > Reviewed-by: Jacob Keller <[email protected]> > > > Signed-off-by: Michal Swiatkowski <[email protected]> > > > --- > > > drivers/net/ethernet/intel/ice/ice.h | 20 ++++++++++++++++++++ > > > drivers/net/ethernet/intel/ice/ice_irq.c | 6 ++++-- > > > drivers/net/ethernet/intel/ice/ice_lib.c | 8 ++++---- > > > 3 files changed, 28 insertions(+), 6 deletions(-) > > > > > > diff --git a/drivers/net/ethernet/intel/ice/ice.h > > > b/drivers/net/ethernet/intel/ice/ice.h > > > index 3d4d8b88631b..354ec2950ff3 100644 > > > --- a/drivers/net/ethernet/intel/ice/ice.h > > > +++ b/drivers/net/ethernet/intel/ice/ice.h > > > @@ -1133,4 +1133,24 @@ static inline struct ice_hw > > > *ice_get_primary_hw(struct ice_pf *pf) > > > else > > > return &pf->adapter->ctrl_pf->hw; > > > } > > > + > > > +/** > > > + * ice_capped_num_cpus - normalize the number of CPUs to a reasonable > > > limit > > > + * > > > + * This function returns the number of online CPUs, but caps it at > > > suitable > > > + * default to prevent excessive resource allocation on systems with very > > > high > > > + * CPU counts. > > > + * > > > + * Note: suitable default is currently at 64, which is reflected in > > > default_cpus > > > + * constant. In most cases there is no much benefit for more than 64 and > > > it is a > > > + * power of 2 number. > > > + * > > > + * Return: number of online CPUs, capped at suitable default. > > > + */ > > > +static inline u16 ice_capped_num_cpus(void) > > > +{ > > > + const int default_cpus = 64; > > > > Maybe we should just use netif_get_num_default_rss_queues() like I did > > in idpf? > > > > Or it still can be too high e.g. on clusters with > 256 CPUs? > > good point, > perhaps we should both use it and change the (kernel) func to cap at 64 >
Sounds good, thanks for pointing the function. Do you think it is ok to cap the generic function? Maybe other vendors want more default queues. What about capping netif_get_num_default_rss_queues() at 64 just for ice? > > > > > + > > > + return min(num_online_cpus(), default_cpus); > > > +} > > > #endif /* _ICE_H_ */ > > Thanks, > > Olek > > >
