Re: [PATCH net-next V6 2/2] net/mlx4_en: Use affinity hint

On Sun, 2014-06-01 at 21:16 -0700, Eric Dumazet wrote:

On Sun, 2014-05-25 at 17:47 +0300, Amir Vadai wrote:

quoted

From: Yuval Atias <redacted>

The “affinity hint” mechanism is used by the user space
daemon, irqbalancer, to indicate a preferred CPU mask for irqs.
Irqbalancer can use this hint to balance the irqs between the
cpus indicated by the mask.

We wish the HCA to preferentially map the IRQs it uses to numa cores
close to it.  To accomplish this, we use cpumask_set_cpu_local_first(), that
sets the affinity hint according the following policy:
First it maps IRQs to “close” numa cores.  If these are exhausted, the
remaining IRQs are mapped to “far” numa cores.

Signed-off-by: Yuval Atias <redacted>
Signed-off-by: Amir Vadai <redacted>
---

  CC [M]  drivers/net/ethernet/mellanox/mlx4/en_netdev.o
drivers/net/ethernet/mellanox/mlx4/en_netdev.c: In function ‘mlx4_en_init_affinity_hint’:
drivers/net/ethernet/mellanox/mlx4/en_netdev.c:1546:23: error: incompatible types when assigning to type ‘cpumask_var_t’ from type ‘void *’
drivers/net/ethernet/mellanox/mlx4/en_netdev.c: In function ‘mlx4_en_free_affinity_hint’:
drivers/net/ethernet/mellanox/mlx4/en_netdev.c:1553:41: error: incompatible types when assigning to type ‘cpumask_var_t’ from type ‘void *’

And :

ERROR: "cpumask_set_cpu_local_first" [drivers/net/ethernet/mellanox/mlx4/mlx4_en.ko] undefined!


$ git grep -n cpumask_set_cpu_local_first
drivers/net/ethernet/mellanox/mlx4/en_netdev.c:1542:    if (cpumask_set_cpu_local_first(ring_idx, numa_node,
include/linux/cpumask.h:260:int cpumask_set_cpu_local_first(int i, int numa_node, cpumask_t *dstp);
lib/cpumask.c:168: * cpumask_set_cpu_local_first - set i'th cpu with local numa cpu's first
lib/cpumask.c:182:int cpumask_set_cpu_local_first(int i, int numa_node, cpumask_t *dstp)
lib/cpumask.c:228:EXPORT_SYMBOL(cpumask_set_cpu_local_first);

Fixes are needed if CONFIG_CPUMASK_OFFSTACK is not used.
	
$ grep CONFIG_CPUMASK_OFFSTACK .config
$ echo $?
1