Skip to contentSkip to conversation

enable VMSPLIT for highmem kernels

RFC PATCH In review Dave Hansen 1 participant 2 messages Aug 2, 2006 Memory management

lore
Share & tools
lore
#0 lore raw

RFC PATCH 1/1 enable VMSPLIT for highmem kernels

---

 lxc-dave/arch/i386/Kconfig |    3 ++-
 1 files changed, 2 insertions(+), 1 deletion(-)
arch/i386/Kconfig renamed from arch/i386/Kconfig~split-for-pae +2 -1
diff -puN arch/i386/Kconfig~split-for-pae arch/i386/Kconfig
@@ -497,7 +497,7 @@ config HIGHMEM64G
 endchoice
 
 choice
-	depends on EXPERIMENTAL && !X86_PAE
+	depends on EXPERIMENTAL
 	prompt "Memory split" if EMBEDDED
 	default VMSPLIT_3G
 	help
@@ -519,6 +519,7 @@ choice
 	config VMSPLIT_3G
 		bool "3G/1G user/kernel split"
 	config VMSPLIT_3G_OPT
+		depends on !HIGHMEM
 		bool "3G/1G user/kernel split (for full 1G low memory)"
 	config VMSPLIT_2G
 		bool "2G/2G user/kernel split"

_

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>

#1 lore raw

Well, I somehow managed to post that without appending my description. Here goes:

The current VMSPLIT Kconfig option is disabled whenever highmem is on. This is a bit screwy because the people who need to change VMSPLIT the most tend to be the ones with highmem and constrained lowmem.

So, remove the highmem dependency. But, re-include the dependency for the "full 1GB of lowmem" option. You can't have the full 1GB of lowmem and highmem because of the need for the vmalloc(), kmap(), etc... areas.

I thought there would be at least a bit of tweaking to do to get it to work, but everything seems OK.

Boot tested on a 4GB x86 machine, and a 12GB 3-node NUMA-Q:

elm3b82:~# cat /proc/meminfo
MemTotal:      3695412 kB
MemFree:       3659540 kB
...
LowTotal:      2909008 kB
LowFree:       2892324 kB
...
elm3b82:~# zgrep PAE /proc/config.gz
CONFIG_X86_PAE=y
larry:~# cat /proc/meminfo
MemTotal:     11845900 kB
MemFree:      11786748 kB
...
LowTotal:      2855180 kB
LowFree:       2830092 kB

-- Dave

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to [email protected]. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"[email protected]"> [email protected] </a>