Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/perf_event: Fix oops due to perf_event_do_pending call
  powerpc/swiotlb: Fix off by one in determining boundary of which ops to use

1 files changed, 48 insertions, 12 deletions

diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 1b16b9a3e49a..0441bbdadbd1 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -532,25 +532,60 @@ void __init iSeries_time_init_early(void)
 }
 #endif /* CONFIG_PPC_ISERIES */
 
-#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_PPC32)
-DEFINE_PER_CPU(u8, perf_event_pending);
+#ifdef CONFIG_PERF_EVENTS
 
-void set_perf_event_pending(void)
+/*
+ * 64-bit uses a byte in the PACA, 32-bit uses a per-cpu variable...
+ */
+#ifdef CONFIG_PPC64
+static inline unsigned long test_perf_event_pending(void)
 {
-        get_cpu_var(perf_event_pending) = 1;
-        set_dec(1);
-        put_cpu_var(perf_event_pending);
+        unsigned long x;
+
+        asm volatile("lbz %0,%1(13)"
+                : "=r" (x)
+                : "i" (offsetof(struct paca_struct, perf_event_pending)));
+        return x;
 }
 
+static inline void set_perf_event_pending_flag(void)
+{
+        asm volatile("stb %0,%1(13)" : :
+                "r" (1),
+                "i" (offsetof(struct paca_struct, perf_event_pending)));
+}
+
+static inline void clear_perf_event_pending(void)
+{
+        asm volatile("stb %0,%1(13)" : :
+                "r" (0),
+                "i" (offsetof(struct paca_struct, perf_event_pending)));
+}
+
+#else /* 32-bit */
+
+DEFINE_PER_CPU(u8, perf_event_pending);
+
+#define set_perf_event_pending_flag()   __get_cpu_var(perf_event_pending) = 1
 #define test_perf_event_pending()       __get_cpu_var(perf_event_pending)
 #define clear_perf_event_pending()      __get_cpu_var(perf_event_pending) = 0
 
-#else  /* CONFIG_PERF_EVENTS && CONFIG_PPC32 */
+#endif /* 32 vs 64 bit */
+
+void set_perf_event_pending(void)
+{
+        preempt_disable();
+        set_perf_event_pending_flag();
+        set_dec(1);
+        preempt_enable();
+}
+
+#else  /* CONFIG_PERF_EVENTS */
 
 #define test_perf_event_pending()       0
 #define clear_perf_event_pending()
 
-#endif /* CONFIG_PERF_EVENTS && CONFIG_PPC32 */
+#endif /* CONFIG_PERF_EVENTS */
 
 /*
  * For iSeries shared processors, we have to let the hypervisor
@@ -582,10 +617,6 @@ void timer_interrupt(struct pt_regs * regs)
         set_dec(DECREMENTER_MAX);
 
 #ifdef CONFIG_PPC32
-        if (test_perf_event_pending()) {
-                clear_perf_event_pending();
-                perf_event_do_pending();
-        }
         if (atomic_read(&ppc_n_lost_interrupts) != 0)
                 do_IRQ(regs);
 #endif
@@ -604,6 +635,11 @@ void timer_interrupt(struct pt_regs * regs)
 
         calculate_steal_time();
 
+        if (test_perf_event_pending()) {
+                clear_perf_event_pending();
+                perf_event_do_pending();
+        }
+
 #ifdef CONFIG_PPC_ISERIES
         if (firmware_has_feature(FW_FEATURE_ISERIES))
                 get_lppaca()->int_dword.fields.decr_int = 0;