[PATCH] Disable fast softints on OMAP (was Re: Status of current on ARM? )

[Mikko Rapeli <mikko.rapeli%teleca.com@localhost>]

On Thu, Nov 13, 2008 at 08:56:43PM -0500, Rafal Boni wrote:
> On Wed, Nov 12, 2008 at 08:46:55AM +0200, Mikko Rapeli wrote:
> > On Tue, Nov 04, 2008 at 11:51:34AM +0200, Mikko Rapeli wrote:
> > > The current kernel is not very well tuned for OMAP 2420 since it takes 
> > > 2 minutes and 44 seconds to boot it to the "Enter pathname of shell..."
> > > point. In comparison our kernel branch takes 19 seconds. Userspace was 
> > > the 
> > > same yesterdays current on both.
> > 
> > An update to the slow boot: current from Aug 5th 2008 boots in 23
> > seconds. Changes since then have slowed the kernel considerably on OMAP
> > 2420.
> 
> Just as a datapoint, this isn't generic to all the evbarm targets; my PXA250
> boots an INSTALL kernel (gzip'ed, with ramdisk) from WinCE in 35-40 sec, and
> from the point of the 2nd-stage loader handing control to the kernel it's ~ 5
> sec to sysinst running.

This is propably because __HAVE_FAST_SOFTINTS isn't enabled on your target
platform.

Current kernel from today, some old userspace:

# time cc -Wall hello.c
      361.09 real         1.24 user         1.23 sys

Current kernel from today, some old userspace and __HAVE_FAST_SOFTINTS
disabled with patch below:

# time cc -Wall hello.c
       10.33 real         0.67 user         1.69 sys

So please, please apply this patch.

commit 6afbed3f0f9d105a68ea4507e8cc386095be33e7
Author: Mikko Rapeli <mikko.rapeli%teleca.com@localhost>
Date:   Fri Nov 14 08:52:36 2008 +0200

    Revert "Enable __HAVE_FAST_SOFTINTS"
    
    This reverts commit f6fa5cb06f805249ecc4a58b2b8a75a37204d041. It has
    over ten fold slowdown effect on OMAP2420. This was suggested by
    Cliff Neighbors. Original commit log follows:
    
    commit f6fa5cb06f805249ecc4a58b2b8a75a37204d041
    Author: Matt Thomas <matt%netbsd.org@localhost>
    Date:   Thu Aug 7 03:59:49 2008 +0000
    
        Enable __HAVE_FAST_SOFTINTS

diff --git a/sys/arch/evbarm/conf/std.tisdp24xx 
b/sys/arch/evbarm/conf/std.tisdp24xx
index dd846db..a7b3b51 100644
--- a/sys/arch/evbarm/conf/std.tisdp24xx
+++ b/sys/arch/evbarm/conf/std.tisdp24xx
@@ -15,7 +15,6 @@ options       EXEC_SCRIPT
 options        ARM32
 options        ARM11_PMC
 options        ARM11_PMC_CCNT_HZ=266000000
-options        __HAVE_FAST_SOFTINTS            # should be in types.h
 #options       PROCESS_ID_IS_CURLWP
 options        KERNEL_BASE_EXT=0x80000000