PATCH: increase heap size for (gpt)zfsboot

[Matt Reimer]

On Wed, Dec 9, 2009 at 7:15 AM, John Baldwin <jhb at freebsd.org> wrote:
> On Tuesday 08 December 2009 6:06:14 pm Matt Reimer wrote:
>> On Tue, Dec 8, 2009 at 5:13 AM, John Baldwin <jhb at freebsd.org> wrote:
>> > On Monday 07 December 2009 7:01:03 pm Matt Reimer wrote:
>> >> Enlarge the heap size for gptzfsboot and zfsboot. This is necessary so
>> >> the ZFS code has enough memory to handle decompression and error
>> >> recovery.
>> >>
>> >> Before this patch the heap grew from the end of the (gpt)zfsboot code
>> >> and static data up to 640KB, possibly overrunning the stack. Now the
>> >> heap is located at 16MB-64MB.
>> >>
>> >> Note that this requires machines with at least 64MB RAM, but this is
>> >> not likely to be a problem on any machine running ZFS.
>> >>
>> >> Sponsored by: VPOP Technologies, Inc.
>> >>
>> >> Matt Reimer
>> >
>> > Unfortunately the 16M - 64M range may not all be useable RAM.  It may contain
>> > ACPI tables, etc.  A robust approach would involve walking the SMAP, etc.  I
>> > just committed some changes to sys/boot/i386/loader/biosmem.c that make it
>> > smarter about choosing a heap region.  I suggest adopting that algorithm for
>> > figuring out a safe heap range.  zfsboot and gptzfsboot should have enough
>> > free space to take the bios_getmem() function.  You can increase the minimum
>> > heap size beyond 3M if desired (though 3M is the minimum the loader will
>> > guarantee currently, and if ZFS needs more than that it likely needs to be
>> > changed in both places).
>>
>> Thanks John. I dropped the bios_getmem() into zfsboot.c and it works
>> for me. How's the attached patch look to you?
>
> I tweaked it slightly (memtop* aren't needed for gptboot, and memsize() isn't
> used anymore).  Can you test the updated version below?

It works. But making bios_getmem() inline causes a compiler warning:

/usr/src/sys/boot/i386/gptzfsboot/../zfsboot/zfsboot.c: In function 'main':
/usr/src/sys/boot/i386/gptzfsboot/../zfsboot/zfsboot.c:353: warning:
inlining failed in call to 'bios_getmem': --param
max-inline-insns-single limit reached
/usr/src/sys/boot/i386/gptzfsboot/../zfsboot/zfsboot.c:620: warning:
called from here

Matt