ppc: Rewrite ppc_get_compat_smt_threads()

To continue consolidation of compatibility mode information, this rewrites
the ppc_get_compat_smt_threads() function using the table of compatiblity
modes in target-ppc/compat.c.

It's not a direct replacement, the new ppc_compat_max_threads() function
has simpler semantics - it just returns the number of threads the cpu
model has, taking into account any compatiblity mode it is in.

This no longer takes into account kvmppc_smt_threads() as the previous
version did.  That check wasn't useful because we check in
ppc_cpu_realizefn() that CPUs aren't instantiated with more threads
than kvm allows (or if we didn't things will already be broken and
this won't make it any worse).

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
This commit is contained in:
David Gibson 2016-10-28 22:35:48 +11:00
parent 9d6f106552
commit 12dbeb16d0
4 changed files with 23 additions and 25 deletions

View file

@ -28,6 +28,7 @@
typedef struct {
uint32_t pvr;
uint64_t pcr;
int max_threads;
} CompatInfo;
static const CompatInfo compat_table[] = {
@ -35,18 +36,22 @@ static const CompatInfo compat_table[] = {
.pvr = CPU_POWERPC_LOGICAL_2_05,
.pcr = PCR_COMPAT_2_07 | PCR_COMPAT_2_06 | PCR_COMPAT_2_05
| PCR_TM_DIS | PCR_VSX_DIS,
.max_threads = 2,
},
{ /* POWER7, ISA2.06 */
.pvr = CPU_POWERPC_LOGICAL_2_06,
.pcr = PCR_COMPAT_2_07 | PCR_COMPAT_2_06 | PCR_TM_DIS,
.max_threads = 4,
},
{
.pvr = CPU_POWERPC_LOGICAL_2_06_PLUS,
.pcr = PCR_COMPAT_2_07 | PCR_COMPAT_2_06 | PCR_TM_DIS,
.max_threads = 4,
},
{ /* POWER8, ISA2.07 */
.pvr = CPU_POWERPC_LOGICAL_2_07,
.pcr = PCR_COMPAT_2_07,
.max_threads = 8,
},
};
@ -89,3 +94,16 @@ void ppc_set_compat(PowerPCCPU *cpu, uint32_t compat_pvr, Error **errp)
}
}
}
int ppc_compat_max_threads(PowerPCCPU *cpu)
{
const CompatInfo *compat = compat_by_pvr(cpu->compat_pvr);
int n_threads = CPU(cpu)->nr_threads;
if (cpu->compat_pvr) {
g_assert(compat);
n_threads = MIN(n_threads, compat->max_threads);
}
return n_threads;
}