Re: [PATCH 2/2] ehea: fix mutex and spinlock use

[Jeff Garzik <jeff@garzik.org>]

Sebastien Dugue wrote:
>   Looks like to me that the ehea_fw_handles.lock mutex and the
> ehea_bcmc_regs.lock spinlock are taken much longer than necessary and could
> as well be pushed inside the functions that need them
> (ehea_update_firmware_handles() and ehea_update_bcmc_registrations())
> rather than at each callsite.
> 
> Signed-off-by: Sebastien Dugue <sebastien.dugue@bull.net>
> ---
>  drivers/net/ehea/ehea_main.c |   26 ++++----------------------
>  1 files changed, 4 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/net/ehea/ehea_main.c b/drivers/net/ehea/ehea_main.c
> index b70c531..c765ec6 100644
> --- a/drivers/net/ehea/ehea_main.c
> +++ b/drivers/net/ehea/ehea_main.c
> @@ -219,9 +219,11 @@ static void ehea_update_firmware_handles(void)
>  	}
>  
>  out_update:
> +	mutex_lock(&ehea_fw_handles.lock);
>  	kfree(ehea_fw_handles.arr);
>  	ehea_fw_handles.arr = arr;
>  	ehea_fw_handles.num_entries = i;
> +	mutex_unlock(&ehea_fw_handles.lock);
>  }
>  
>  static void ehea_update_bcmc_registrations(void)
> @@ -293,9 +295,11 @@ static void ehea_update_bcmc_registrations(void)
>  	}
>  
>  out_update:
> +	spin_lock(&ehea_bcmc_regs.lock);
>  	kfree(ehea_bcmc_regs.arr);
>  	ehea_bcmc_regs.arr = arr;
>  	ehea_bcmc_regs.num_entries = i;
> +	spin_unlock(&ehea_bcmc_regs.lock);
>  }
>  
>  static struct net_device_stats *ehea_get_stats(struct net_device *dev)
> @@ -1770,8 +1774,6 @@ static int ehea_set_mac_addr(struct net_device *dev, void *sa)
>  
>  	memcpy(dev->dev_addr, mac_addr->sa_data, dev->addr_len);
>  
> -	spin_lock(&ehea_bcmc_regs.lock);
> -
>  	/* Deregister old MAC in pHYP */
>  	if (port->state == EHEA_PORT_UP) {
>  		ret = ehea_broadcast_reg_helper(port, H_DEREG_BCMC);
> @@ -1792,7 +1794,6 @@ static int ehea_set_mac_addr(struct net_device *dev, void *sa)
>  
>  out_upregs:
>  	ehea_update_bcmc_registrations();
> -	spin_unlock(&ehea_bcmc_regs.lock);
>  out_free:
>  	kfree(cb0);
>  out:
> @@ -1954,8 +1955,6 @@ static void ehea_set_multicast_list(struct net_device *dev)
>  	}
>  	ehea_promiscuous(dev, 0);
>  
> -	spin_lock(&ehea_bcmc_regs.lock);
> -
>  	if (dev->flags & IFF_ALLMULTI) {
>  		ehea_allmulti(dev, 1);
>  		goto out;
> @@ -1985,7 +1984,6 @@ static void ehea_set_multicast_list(struct net_device *dev)
>  	}
>  out:
>  	ehea_update_bcmc_registrations();
> -	spin_unlock(&ehea_bcmc_regs.lock);
>  	return;
>  }
>  
> @@ -2466,8 +2464,6 @@ static int ehea_up(struct net_device *dev)
>  	if (port->state == EHEA_PORT_UP)
>  		return 0;
>  
> -	mutex_lock(&ehea_fw_handles.lock);
> -
>  	ret = ehea_port_res_setup(port, port->num_def_qps,
>  				  port->num_add_tx_qps);
>  	if (ret) {
> @@ -2504,8 +2500,6 @@ static int ehea_up(struct net_device *dev)
>  		}
>  	}
>  
> -	spin_lock(&ehea_bcmc_regs.lock);
> -
>  	ret = ehea_broadcast_reg_helper(port, H_REG_BCMC);
>  	if (ret) {
>  		ret = -EIO;
> @@ -2527,10 +2521,8 @@ out:
>  		ehea_info("Failed starting %s. ret=%i", dev->name, ret);
>  
>  	ehea_update_bcmc_registrations();
> -	spin_unlock(&ehea_bcmc_regs.lock);
>  
>  	ehea_update_firmware_handles();
> -	mutex_unlock(&ehea_fw_handles.lock);
>  
>  	return ret;
>  }
> @@ -2580,9 +2572,6 @@ static int ehea_down(struct net_device *dev)
>  	if (port->state == EHEA_PORT_DOWN)
>  		return 0;
>  
> -	mutex_lock(&ehea_fw_handles.lock);
> -
> -	spin_lock(&ehea_bcmc_regs.lock);
>  	ehea_drop_multicast_list(dev);
>  	ehea_broadcast_reg_helper(port, H_DEREG_BCMC);
>  
> @@ -2591,7 +2580,6 @@ static int ehea_down(struct net_device *dev)
>  	port->state = EHEA_PORT_DOWN;
>  
>  	ehea_update_bcmc_registrations();
> -	spin_unlock(&ehea_bcmc_regs.lock);
>  
>  	ret = ehea_clean_all_portres(port);
>  	if (ret)
> @@ -2599,7 +2587,6 @@ static int ehea_down(struct net_device *dev)
>  			  dev->name, ret);
>  
>  	ehea_update_firmware_handles();
> -	mutex_unlock(&ehea_fw_handles.lock);
>  
>  	return ret;
>  }
> @@ -3378,7 +3365,6 @@ static int __devinit ehea_probe_adapter(struct of_device *dev,
>  		ehea_error("Invalid ibmebus device probed");
>  		return -EINVAL;
>  	}
> -	mutex_lock(&ehea_fw_handles.lock);
>  
>  	adapter = kzalloc(sizeof(*adapter), GFP_KERNEL);
>  	if (!adapter) {
> @@ -3462,7 +3448,6 @@ out_free_ad:
>  
>  out:
>  	ehea_update_firmware_handles();
> -	mutex_unlock(&ehea_fw_handles.lock);
>  	return ret;
>  }
>  
> @@ -3481,8 +3466,6 @@ static int __devexit ehea_remove(struct of_device *dev)
>  
>  	flush_scheduled_work();
>  
> -	mutex_lock(&ehea_fw_handles.lock);
> -
>  	ibmebus_free_irq(adapter->neq->attr.ist1, adapter);
>  	tasklet_kill(&adapter->neq_tasklet);

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