[lkml]   [2006]   [Feb]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
SubjectRe: Patch to reorder functions in the vmlinux to a defined order

On Thu, 23 Feb 2006, Arjan van de Ven wrote:
> >
> > I think you would first need to move the code first for that. Currently it starts
> > at 1MB, which means 1MB is already wasted of the aligned 2MB TLB entry.
> >
> > I wouldn't have a problem with moving the 64bit kernel to 2MB though.
> that was easy since it's a Config entry already ;)

Btw, the "low TLB entry" for the direct-mapped case can't be used as a
hugetlb page anyway, due to the MMU splitting it up due to the special
MTRR regions, if I recall correctly.

So this is probably a bigger performance win than just the difference
between using one or two TLB entries.

The same should be true on x86, btw. Where we should use a physical start
address of 4MB for best performance.

Does anybody want to run benchmarks? (Totally untested, may not boot,
might physically accost your pets for all I know).


diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig
index 0afec85..d2b1df8 100644
--- a/arch/i386/Kconfig
+++ b/arch/i386/Kconfig
@@ -715,7 +715,7 @@ config PHYSICAL_START
hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)

default "0x1000000" if CRASH_DUMP
- default "0x100000"
+ default "0x400000"
This gives the physical address where the kernel is loaded. Normally
for regular kernels this value is 0x100000 (1MB). But in the case
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at
 \ /
  Last update: 2009-11-18 23:46    [W:0.113 / U:7.828 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site