This patch adds in the necessary support for sparsemem such that
x86-64 kernels may use sparsemem as an alternative to discontigmem
for NUMA kernels. Note that this does no preclude one from
continuing to build NUMA kernels using discontigmem, but merely
allows the option to build NUMA kernels with sparsemem.
Interestingly, the use of sparsemem in lieu of discontigmem in NUMA
kernels results in reduced text size for otherwise equivalent
kernels as shown in the example builds below:
text data bss dec hex filename
2371036 765884 1237108 4374028 42be0c vmlinux.discontig
2366549 776484 1302772 4445805 43d66d vmlinux.sparse
Signed-off-by: Matt Tolentino <[email protected]>
Signed-off-by: Dave Hansen <[email protected]>
---
arch/x86_64/kernel/setup.c | 10 ++++++++--
arch/x86_64/mm/numa.c | 8 ++++++++
include/asm-x86_64/bitops.h | 2 --
include/asm-x86_64/sparsemem.h | 26 ++++++++++++++++++++++++++
4 files changed, 42 insertions(+), 4 deletions(-)
diff -urNp linux-2.6.12-rc4-mm2/arch/x86_64/kernel/setup.c linux-2.6.12-rc4-mm2-m/arch/x86_64/kernel/setup.c
--- linux-2.6.12-rc4-mm2/arch/x86_64/kernel/setup.c 2005-05-18 07:50:07.000000000 -0400
+++ linux-2.6.12-rc4-mm2-m/arch/x86_64/kernel/setup.c 2005-05-18 07:51:13.000000000 -0400
@@ -40,6 +40,7 @@
#include <linux/acpi.h>
#include <linux/kallsyms.h>
#include <linux/edd.h>
+#include <linux/mmzone.h>
#include <linux/kexec.h>
#include <asm/mtrr.h>
#include <asm/uaccess.h>
@@ -400,9 +401,12 @@ static __init void parse_cmdline_early (
}
#ifndef CONFIG_NUMA
-static void __init contig_initmem_init(void)
+static void __init
+contig_initmem_init(unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long bootmap_size, bootmap;
+
+ memory_present(0, start_pfn, end_pfn);
bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size);
if (bootmap == -1L)
@@ -579,7 +583,7 @@ void __init setup_arch(char **cmdline_p)
#ifdef CONFIG_NUMA
numa_initmem_init(0, end_pfn);
#else
- contig_initmem_init();
+ contig_initmem_init(0, end_pfn);
#endif
/* Reserve direct mapping */
@@ -645,6 +649,8 @@ void __init setup_arch(char **cmdline_p)
reserve_bootmem(crashk_res.start, crashk_res.end - crashk_res.start + 1);
}
#endif
+
+ sparse_init();
paging_init();
check_ioapic();
diff -urNp linux-2.6.12-rc4-mm2/arch/x86_64/mm/numa.c linux-2.6.12-rc4-mm2-m/arch/x86_64/mm/numa.c
--- linux-2.6.12-rc4-mm2/arch/x86_64/mm/numa.c 2005-05-07 01:20:31.000000000 -0400
+++ linux-2.6.12-rc4-mm2-m/arch/x86_64/mm/numa.c 2005-05-18 07:51:13.000000000 -0400
@@ -66,6 +66,13 @@ int __init compute_hash_shift(struct nod
return -1;
}
+#ifdef CONFIG_SPARSEMEM
+int early_pfn_to_nid(unsigned long pfn)
+{
+ return phys_to_nid(pfn << PAGE_SHIFT);
+}
+#endif
+
/* Initialize bootmem allocator for a node */
void __init setup_node_bootmem(int nodeid, unsigned long start, unsigned long end)
{
@@ -80,6 +87,7 @@ void __init setup_node_bootmem(int nodei
start_pfn = start >> PAGE_SHIFT;
end_pfn = end >> PAGE_SHIFT;
+ memory_present(nodeid, start_pfn, end_pfn);
nodedata_phys = find_e820_area(start, end, pgdat_size);
if (nodedata_phys == -1L)
panic("Cannot find memory pgdat in node %d\n", nodeid);
diff -urNp linux-2.6.12-rc4-mm2/include/asm-x86_64/bitops.h linux-2.6.12-rc4-mm2-m/include/asm-x86_64/bitops.h
--- linux-2.6.12-rc4-mm2/include/asm-x86_64/bitops.h 2005-05-07 01:20:31.000000000 -0400
+++ linux-2.6.12-rc4-mm2-m/include/asm-x86_64/bitops.h 2005-05-18 07:51:13.000000000 -0400
@@ -411,8 +411,6 @@ static __inline__ int ffs(int x)
/* find last set bit */
#define fls(x) generic_fls(x)
-#define ARCH_HAS_ATOMIC_UNSIGNED 1
-
#endif /* __KERNEL__ */
#endif /* _X86_64_BITOPS_H */
diff -urNp linux-2.6.12-rc4-mm2/include/asm-x86_64/sparsemem.h linux-2.6.12-rc4-mm2-m/include/asm-x86_64/sparsemem.h
--- linux-2.6.12-rc4-mm2/include/asm-x86_64/sparsemem.h 1969-12-31 19:00:00.000000000 -0500
+++ linux-2.6.12-rc4-mm2-m/include/asm-x86_64/sparsemem.h 2005-05-18 07:51:13.000000000 -0400
@@ -0,0 +1,26 @@
+#ifndef _ASM_X86_64_SPARSEMEM_H
+#define _ASM_X86_64_SPARSEMEM_H 1
+
+#ifdef CONFIG_SPARSEMEM
+
+/*
+ * generic non-linear memory support:
+ *
+ * 1) we will not split memory into more chunks than will fit into the flags
+ * field of the struct page
+ *
+ * SECTION_SIZE_BITS 2^n: size of each section
+ * MAX_PHYSADDR_BITS 2^n: max size of physical address space
+ * MAX_PHYSMEM_BITS 2^n: how much memory we can have in that space
+ *
+ */
+
+#define SECTION_SIZE_BITS 27 /* matt - 128 is convenient right now */
+#define MAX_PHYSADDR_BITS 40
+#define MAX_PHYSMEM_BITS 40
+
+extern int early_pfn_to_nid(unsigned long pfn);
+
+#endif /* CONFIG_SPARSEMEM */
+
+#endif /* _ASM_X86_64_SPARSEMEM_H */
> @@ -400,9 +401,12 @@ static __init void parse_cmdline_early (
> }
>
> #ifndef CONFIG_NUMA
> -static void __init contig_initmem_init(void)
> +static void __init
> +contig_initmem_init(unsigned long start_pfn, unsigned long end_pfn)
> {
> unsigned long bootmap_size, bootmap;
> +
> + memory_present(0, start_pfn, end_pfn);
Watch indentation.
Rest looks good.
-Andi
>From [email protected] Wed May 18 09:33:00 2005
>
>> @@ -400,9 +401,12 @@ static __init void parse_cmdline_early (
>> }
>>
>> #ifndef CONFIG_NUMA
>> -static void __init contig_initmem_init(void)
>> +static void __init
>> +contig_initmem_init(unsigned long start_pfn, unsigned long end_pfn)
>> {
>> unsigned long bootmap_size, bootmap;
>> +
>> + memory_present(0, start_pfn, end_pfn);
>
>Watch indentation.
Weird. I just looked again and this is tabbed properly, although
the rest of the lines in this function are indented with individual
spaces.
>Rest looks good.
Thanks!
matt