[patch] cap code_gen_buffer_size on ia64

[patch] cap code_gen_buffer_size on ia64

[Jes Sorensen]

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Hi,

This one limits the code_gen_buffer_size on ia64, phys_mem_size/4
really gets out of hand when you boot say a 64GB guest.

Cheers,
Jes


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Cap code_gen_buffer_size on ia64 - it quickly goes out of hand otherwise
when booting larger guests.

Signed-off-by: Jes Sorensen <jes@sgi.com>

---
 qemu/exec.c |    4 ++++
 1 file changed, 4 insertions(+)

Index: kvm-userspace.git/qemu/exec.c
===================================================================
--- kvm-userspace.git.orig/qemu/exec.c
+++ kvm-userspace.git/qemu/exec.c
@@ -443,6 +443,10 @@
         start = (void *) 0x60000000UL;
         if (code_gen_buffer_size > (512 * 1024 * 1024))
             code_gen_buffer_size = (512 * 1024 * 1024);
+#elif defined(__ia64__)
+	/* cap the mapping, don't want it totally out of hand */
+        if (code_gen_buffer_size > (512 * 1024 * 1024))
+            code_gen_buffer_size = (512 * 1024 * 1024);
 #endif
         code_gen_buffer = mmap(start, code_gen_buffer_size,
                                PROT_WRITE | PROT_READ | PROT_EXEC,

Re: [patch] cap code_gen_buffer_size on ia64

[Avi Kivity]

Jes Sorensen wrote:
> Hi,
>
> This one limits the code_gen_buffer_size on ia64, phys_mem_size/4
> really gets out of hand when you boot say a 64GB guest.
>

ia64 doesn't codegen; why not set it to zero?

(and the phys_ram_size / 4 heuristic is ridiculous; code size doesn't 
scale with guest size)

-- 
error compiling committee.c: too many arguments to function

Re: [patch] cap code_gen_buffer_size on ia64

[Jes Sorensen]

Avi Kivity wrote:
> ia64 doesn't codegen; why not set it to zero?
> 
> (and the phys_ram_size / 4 heuristic is ridiculous; code size doesn't 
> scale with guest size)

That works too - I didn't really know this part too well, but I hit
the problem that I was unable to allocate the space because of 64 bit
issues.

I'll whip up a patch to disable it for ia64.

Cheers,
Jes