Re: [PATCH]intel-iommu batched iotlb flushes

[Randy Dunlap <randy.dunlap@oracle.com>]

mark gross wrote:
>  
> Index: linux-2.6.24-mm1/drivers/pci/intel-iommu.c
> ===================================================================
> --- linux-2.6.24-mm1.orig/drivers/pci/intel-iommu.c	2008-02-12 07:12:06.000000000 -0800
> +++ linux-2.6.24-mm1/drivers/pci/intel-iommu.c	2008-02-12 07:47:04.000000000 -0800

> @@ -1672,7 +1702,30 @@
>  	for_each_drhd_unit(drhd) {
>  		if (drhd->ignored)
>  			continue;
> -		iommu = alloc_iommu(drhd);
> +		g_num_of_iommus++;
> +	}
> +
> +	nlongs = BITS_TO_LONGS(g_num_of_iommus);
> +	g_iommus_to_flush = kzalloc(nlongs * sizeof(unsigned long), GFP_KERNEL);
> +	if (!g_iommus_to_flush) {
> +		printk(KERN_ERR "Intel-IOMMU: \
> +			Allocating bitmap array failed\n");

I think that will make a string like below:
Intel-IOMMU: 			Allocating bitmap array failed

> +		return -ENOMEM;
> +	}
> +
> +	g_iommus = kzalloc(g_num_of_iommus * sizeof(*iommu), GFP_KERNEL);
> +	if (!g_iommus) {
> +		kfree(g_iommus_to_flush);
> +		ret = -ENOMEM;
> +		goto error;
> +	}
> +
> +	i = 0;
> +	for_each_drhd_unit(drhd) {
> +		if (drhd->ignored)
> +			continue;
> +		iommu = alloc_iommu(&g_iommus[i], drhd);
> +		i++;
>  		if (!iommu) {
>  			ret = -ENOMEM;
>  			goto error;

> Index: linux-2.6.24-mm1/Documentation/kernel-parameters.txt
> ===================================================================
> --- linux-2.6.24-mm1.orig/Documentation/kernel-parameters.txt	2008-02-12 07:12:06.000000000 -0800
> +++ linux-2.6.24-mm1/Documentation/kernel-parameters.txt	2008-02-12 07:47:02.000000000 -0800
> @@ -822,6 +822,10 @@
>  			than 32 bit addressing. The default is to look
>  			for translation below 32 bit and if not available
>  			then look in the higher range.
> +		strict [Default Off]
> +			With this option on every umap_signal opperation will

			                          unmap_single operation

> +			result in a hardware IOTLB flush opperation as opposed
> +			to batching them for performance.
>  
>  	io_delay=	[X86-32,X86-64] I/O delay method
>  		0x80


-- 
~Randy