[PATCH] x86: Fix boot on uniprocessor systems

From: Artem Fetishev
Date: Mon Mar 24 2014 - 07:01:02 EST


On x86 uniprocessor systems topology_physical_package_id() returns -1 which
causes rapl_cpu_prepare() to leave rapl_pmu variable uninitialized which leads
to GPF in rapl_pmu_init(). See arch/x86/kernel/cpu/perf_event_intel_rapl.c.

It turns out that physical_package_id and core_id can actually be retreived for
uniprocessor systems too. Enabling them also fixes rapl_pmu code.

Signed-off-by: Artem Fetishev <artem_fetishev@xxxxxxxx>
---
diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index d35f24e..1306d11 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -119,9 +119,10 @@ static inline void setup_node_to_cpumask_map(void) { }

extern const struct cpumask *cpu_coregroup_mask(int cpu);

-#ifdef ENABLE_TOPO_DEFINES
#define topology_physical_package_id(cpu) (cpu_data(cpu).phys_proc_id)
#define topology_core_id(cpu) (cpu_data(cpu).cpu_core_id)
+
+#ifdef ENABLE_TOPO_DEFINES
#define topology_core_cpumask(cpu) (per_cpu(cpu_core_map, cpu))
#define topology_thread_cpumask(cpu) (per_cpu(cpu_sibling_map, cpu))
#endif
--
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