Commit e8579e72 authored Aug 04, 2005 by Alex Williamson Committed by Tony Luck Aug 18, 2005

[IA64, X86_64] fix swiotlb sizing



   Fix swiotlb sizing to match what the comments and the kernel
parameters documentation indicate.  Given a default 16k page size kernel
(ia64) and a 2k swiotlb page size, we're off by a multiple of 8 trying
to size the swiotlb.  When specified on the boot line, the swiotlb is
made 8x bigger than requested.  When left to the default value, it's 8x
smaller than the comments indicate.  For x86_64 the multiplier would be
2x.  The patch below fixes this.  Now, what's a good default swiotlb
size?  Apparently we don't really need 64MB.

Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

parent 30d5b64b

arch/ia64/lib/swiotlb.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -93,8 +93,7 @@ static int __init
		setup_io_tlb_npages(char *str)
		{
		if (isdigit(*str)) {
		io_tlb_nslabs = simple_strtoul(str, &str, 0) <<
		(PAGE_SHIFT - IO_TLB_SHIFT);
		io_tlb_nslabs = simple_strtoul(str, &str, 0);
		/* avoid tail segment of size < IO_TLB_SEGSIZE */
		io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
		}
		@@ -117,7 +116,7 @@ swiotlb_init_with_default_size (size_t default_size)
		unsigned long i;

		if (!io_tlb_nslabs) {
		io_tlb_nslabs = (default_size >> PAGE_SHIFT);
		io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
		io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
		}

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