perf, arch: Cleanup perf-pmu init vs lockup-detector

The perf hardware pmu got initialized at various points in the boot,
some before early_initcall() some after (notably arch_initcall).

The problem is that the NMI lockup detector is ran from early_initcall()
and expects the hardware pmu to be present.

Sanitize this by moving all architecture hardware pmu implementations to
initialize at early_initcall() and move the lockup detector to an explicit
initcall right after that.

Cc: paulus <paulus@samba.org>
Cc: davem <davem@davemloft.net>
Cc: Michael Cree <mcree@orcon.net.nz>
Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1290707759.2145.119.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

3 files changed, 5 insertions, 8 deletions

diff --git a/arch/sparc/include/asm/perf_event.h b/arch/sparc/include/asm/perf_event.h
index 6e8bfa1786da..4d3dbe3703e9 100644
--- a/arch/sparc/include/asm/perf_event.h
+++ b/arch/sparc/include/asm/perf_event.h
@@ -4,8 +4,6 @@
 #ifdef CONFIG_PERF_EVENTS
 #include <asm/ptrace.h>
 
-extern void init_hw_perf_events(void);
-
 #define perf_arch_fetch_caller_regs(regs, ip)           \
 do {                                                    \
         unsigned long _pstate, _asi, _pil, _i7, _fp;    \
@@ -26,8 +24,6 @@ do {							\
         (regs)->u_regs[UREG_I6] = _fp;                  \
         (regs)->u_regs[UREG_I7] = _i7;                  \
 } while (0)
-#else
-static inline void init_hw_perf_events(void)    { }
 #endif
 
 #endif
diff --git a/arch/sparc/kernel/nmi.c b/arch/sparc/kernel/nmi.c
index a4bd7ba74c89..300f810142f5 100644
--- a/arch/sparc/kernel/nmi.c
+++ b/arch/sparc/kernel/nmi.c
@@ -270,8 +270,6 @@ int __init nmi_init(void)
                         atomic_set(&nmi_active, -1);
                 }
         }
-        if (!err)
-                init_hw_perf_events();
 
         return err;
 }
diff --git a/arch/sparc/kernel/perf_event.c b/arch/sparc/kernel/perf_event.c
index 0d6deb55a2ae..75c5b1263970 100644
--- a/arch/sparc/kernel/perf_event.c
+++ b/arch/sparc/kernel/perf_event.c
@@ -1307,20 +1307,23 @@ static bool __init supported_pmu(void)
         return false;
 }
 
-void __init init_hw_perf_events(void)
+int __init init_hw_perf_events(void)
 {
         pr_info("Performance events: ");
 
         if (!supported_pmu()) {
                 pr_cont("No support for PMU type '%s'\n", sparc_pmu_type);
-                return;
+                return 0;
         }
 
         pr_cont("Supported PMU type is '%s'\n", sparc_pmu_type);
 
         perf_pmu_register(&pmu);
         register_die_notifier(&perf_event_nmi_notifier);
+
+        return 0;
 }
+early_initcall(init_hw_perf_event);
 
 void perf_callchain_kernel(struct perf_callchain_entry *entry,
                            struct pt_regs *regs)