Subject: Re: [PATCH 0/8] v2 De-Couple sysfs memory directories from memory sections

From: Robin Holt <[email-masked]>
Date: Thu, 30 Sep 2010 11:39:39 -0500

On Wed, Sep 29, 2010 at 02:28:30PM -0500, Robin Holt wrote:
> On Tue, Sep 28, 2010 at 01:17:33PM -0500, Nathan Fontenot wrote:
...
> My next task is to implement a x86_64 SGI UV specific chunk of code
> to memory_block_size_bytes().  Would you consider adding that to your
> patch set?  I expect to have that either later today or early tomorrow.

The patch is below.

I left things at a u32, but I would really like it if you changed to an
unsigned long and adjusted my patch for me.

Thanks,
Robin

------------------------------------------------------------------------
Subject: [Patch] Implement memory_block_size_bytes for x86_64 when CONFIG_X86_UV

Nathan Fontenot has implemented a patch set for large memory configuration
systems which will combine drivers/base/memory.c memory sections
together into memory blocks with the default behavior being
unchanged from the current behavior.

In his patch set, he implements a memory_block_size_bytes() function
for PPC.  This is the equivalent patch for x86_64 when it has
CONFIG_X86_UV set.

Signed-off-by: Robin Holt <[email-masked]>
Signed-off-by: Jack Steiner <[email-masked]>
To: Nathan Fontenot <[email-masked]>
Cc: Ingo Molnar <[email-masked]>
Cc: Thomas Gleixner <[email-masked]>
Cc: "H. Peter Anvin" <[email-masked]>
Cc: lkml <[email-masked]>

---

 arch/x86/mm/init_64.c |   15 +++++++++++++++
 1 file changed, 15 insertions(+)

Index: memory_block/arch/x86/mm/init_64.c
===================================================================
--- memory_block.orig/arch/x86/mm/init_64.c	2010-09-29 14:46:50.711824616 -0500
+++ memory_block/arch/x86/mm/init_64.c	2010-09-29 14:46:55.683997672 -0500
@@ -50,6 +50,7 @@
 #include <asm/numa.h>
 #include <asm/cacheflush.h>
 #include <asm/init.h>
+#include <asm/uv/uv.h>
 #include <linux/bootmem.h>
 
 static unsigned long dma_reserve __initdata;
@@ -928,6 +929,20 @@ const char *arch_vma_name(struct vm_area
 	return NULL;
 }
 
+#ifdef CONFIG_X86_UV
+#define MIN_MEMORY_BLOCK_SIZE   (1 << SECTION_SIZE_BITS)
+
+u32 memory_block_size_bytes(void)
+{
+	if (is_uv_system()) {
+		printk("UV: memory block size 2GB\n");
+		return 2UL * 1024 * 1024 * 1024;
+	}
+	return MIN_MEMORY_BLOCK_SIZE;
+}
+#endif
+
+
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
 /*
  * Initialise the sparsemem vmemmap using huge-pages at the PMD level.