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Unbreak large mem support by removing kqemu

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kqemu introduces a number of restrictions on the i386 target.  The worst is that
it prevents large memory from working in the default build.

Furthermore, kqemu is fundamentally flawed in a number of ways.  It relies on
the TSC as a time source which will not be reliable on a multiple processor
system in userspace.  Since most modern processors are multicore, this severely
limits the utility of kqemu.

kvm is a viable alternative for people looking to accelerate qemu and has the
benefit of being supported by the upstream Linux kernel.  If someone can
implement work arounds to remove the restrictions introduced by kqemu, I'm
happy to avoid and/or revert this patch.

N.B. kqemu will still function in the 0.11 series but this patch removes it from
the 0.12 series.

Paul, please Ack or Nack this patch.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Anthony Liguori 2009-08-10 17:07:24 -05:00
parent 0953a80f04
commit 4a1418e07b
24 changed files with 8 additions and 1722 deletions
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12
hw/pc.c
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@ -122,17 +122,7 @@ static void ioportF0_write(void *opaque, uint32_t addr, uint32_t data)
/* TSC handling */
uint64_t cpu_get_tsc(CPUX86State *env)
{
/* Note: when using kqemu, it is more logical to return the host TSC
because kqemu does not trap the RDTSC instruction for
performance reasons */
#ifdef CONFIG_KQEMU
if (env->kqemu_enabled) {
return cpu_get_real_ticks();
} else
#endif
{
return cpu_get_ticks();
}
return cpu_get_ticks();
}
/* SMM support */