linux/arch
Andres Salomon b5318d302f x86, olpc: Speed up device tree creation during boot
Calling alloc_bootmem() for tiny chunks of memory over and over is really
slow; on an XO-1, it caused the time between when the kernel started
booting and when the display came alive (post-lxfb probe) to increase
to 44s.  This patch optimizes the prom_early_alloc function by
calling alloc_bootmem for 4k-sized blocks of memory, and handing out
chunks of that to callers.  With this patch, the time between kernel load
and display initialization decreased to 23s.  If there's a better way to
do this early in the boot process, please let me know.

(Note: increasing the chunk size to 16k didn't noticably affect boot time,
and wasted 9k.)

v4: clarify comment, requested by hpa
v3: fix wasted memory buglet found by Milton Miller, and style fix.
v2: reorder prom_early_alloc as suggested by Grant.

Signed-off-by: Andres Salomon <dilinger@queued.net>
LKML-Reference: <20101129153951.74202a84@queued.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-12-15 17:11:40 -08:00
..
alpha Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6 2010-10-28 16:16:39 -07:00
arm ARM: tegra: fix regression from addruart rewrite 2010-12-06 20:07:57 -08:00
avr32 Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6 2010-10-28 16:16:39 -07:00
blackfin BKL: remove extraneous #include <smp_lock.h> 2010-11-17 08:59:32 -08:00
cris Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6 2010-10-28 16:16:39 -07:00
frv BKL: remove extraneous #include <smp_lock.h> 2010-11-17 08:59:32 -08:00
h8300 BKL: remove extraneous #include <smp_lock.h> 2010-11-17 08:59:32 -08:00
ia64 SCSI host lock push-down 2010-11-16 13:33:23 -08:00
m32r Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6 2010-10-28 16:16:39 -07:00
m68k BKL: remove extraneous #include <smp_lock.h> 2010-11-17 08:59:32 -08:00
m68knommu BKL: remove extraneous #include <smp_lock.h> 2010-11-17 08:59:32 -08:00
microblaze Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6 2010-10-28 16:16:39 -07:00
mips Merge git://git.infradead.org/mtd-2.6 2010-10-30 08:31:35 -07:00
mn10300 MN10300: Implement asm/syscall.h 2010-12-03 09:18:53 -08:00
parisc parisc: convert the rest of the irq handlers to simple/percpu 2010-12-04 11:15:19 -05:00
powerpc powerpc: Use call_rcu_sched() for pagetables 2010-11-30 10:42:20 +11:00
s390 [S390] nmi: fix clock comparator revalidation 2010-11-25 09:52:59 +01:00
score Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6 2010-10-28 16:16:39 -07:00
sh Merge branch 'sh/urgent' into sh-fixes-for-linus 2010-12-03 14:42:29 +09:00
sparc BKL: remove extraneous #include <smp_lock.h> 2010-11-17 08:59:32 -08:00
tile Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile 2010-11-25 07:42:32 +09:00
um uml: disable winch irq before freeing handler data 2010-11-25 06:50:39 +09:00
x86 x86, olpc: Speed up device tree creation during boot 2010-12-15 17:11:40 -08:00
xtensa Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6 2010-10-28 16:16:39 -07:00
.gitignore
Kconfig jump label: Add work around to i386 gcc asm goto bug 2010-10-29 14:45:29 -04:00