perf_event: x86: Clean up some of the u64/long bitmask casting

We need this to be u64 for direct assigment, but the bitmask functions
all work on unsigned long, leading to cast heaven, solve this by using a
union.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <20100122155535.595961269@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/cpu/perf_event.c

@@ -69,10 +69,11 @@ struct debug_store {
 	u64	pebs_event_reset[MAX_PEBS_EVENTS];
 };
 
-#define BITS_TO_U64(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(u64))
-
 struct event_constraint {
-	u64	idxmsk[BITS_TO_U64(X86_PMC_IDX_MAX)];
+	union {
+		unsigned long	idxmsk[BITS_TO_LONGS(X86_PMC_IDX_MAX)];
+		u64		idxmsk64[1];
+	};
 	int	code;
 	int	cmask;
 };
@@ -91,12 +92,13 @@ struct cpu_hw_events {
 };
 
 #define EVENT_CONSTRAINT(c, n, m) { 	\
+	{ .idxmsk64[0] = (n) },		\
 	.code = (c),			\
 	.cmask = (m),			\
-	.idxmsk[0] = (n) }
+}
 
 #define EVENT_CONSTRAINT_END \
-	{ .code = 0, .cmask = 0, .idxmsk[0] = 0 }
+	EVENT_CONSTRAINT(0, 0, 0)
 
 #define for_each_event_constraint(e, c) \
 	for ((e) = (c); (e)->cmask; (e)++)
@@ -126,8 +128,11 @@ struct x86_pmu {
 	u64		intel_ctrl;
 	void		(*enable_bts)(u64 config);
 	void		(*disable_bts)(void);
-	void		(*get_event_constraints)(struct cpu_hw_events *cpuc, struct perf_event *event, u64 *idxmsk);
-	void		(*put_event_constraints)(struct cpu_hw_events *cpuc, struct perf_event *event);
+	void		(*get_event_constraints)(struct cpu_hw_events *cpuc,
+						 struct perf_event *event,
+						 unsigned long *idxmsk);
+	void		(*put_event_constraints)(struct cpu_hw_events *cpuc,
+						 struct perf_event *event);
 	const struct event_constraint *event_constraints;
 };
 
@@ -2144,14 +2149,11 @@ perf_event_nmi_handler(struct notifier_block *self,
 	return NOTIFY_STOP;
 }
 
-static struct event_constraint bts_constraint = {
-	.code = 0,
-	.cmask = 0,
-	.idxmsk[0] = 1ULL << X86_PMC_IDX_FIXED_BTS
-};
+static struct event_constraint bts_constraint =
+	EVENT_CONSTRAINT(0, 1ULL << X86_PMC_IDX_FIXED_BTS, 0);
 
 static int intel_special_constraints(struct perf_event *event,
-				     u64 *idxmsk)
+				     unsigned long *idxmsk)
 {
 	unsigned int hw_event;
 
@@ -2171,14 +2173,14 @@ static int intel_special_constraints(struct perf_event *event,
 
 static void intel_get_event_constraints(struct cpu_hw_events *cpuc,
 					struct perf_event *event,
-					u64 *idxmsk)
+					unsigned long *idxmsk)
 {
 	const struct event_constraint *c;
 
 	/*
 	 * cleanup bitmask
 	 */
-	bitmap_zero((unsigned long *)idxmsk, X86_PMC_IDX_MAX);
+	bitmap_zero(idxmsk, X86_PMC_IDX_MAX);
 
 	if (intel_special_constraints(event, idxmsk))
 		return;
@@ -2186,10 +2188,7 @@ static void intel_get_event_constraints(struct cpu_hw_events *cpuc,
 	if (x86_pmu.event_constraints) {
 		for_each_event_constraint(c, x86_pmu.event_constraints) {
 			if ((event->hw.config & c->cmask) == c->code) {
-
-				bitmap_copy((unsigned long *)idxmsk,
-					    (unsigned long *)c->idxmsk,
-					    X86_PMC_IDX_MAX);
+				bitmap_copy(idxmsk, c->idxmsk, X86_PMC_IDX_MAX);
 				return;
 			}
 		}
@@ -2200,10 +2199,10 @@ static void intel_get_event_constraints(struct cpu_hw_events *cpuc,
 
 static void amd_get_event_constraints(struct cpu_hw_events *cpuc,
 				      struct perf_event *event,
-				      u64 *idxmsk)
+				      unsigned long *idxmsk)
 {
 	/* no constraints, means supports all generic counters */
-	bitmap_fill((unsigned long *)idxmsk, x86_pmu.num_events);
+	bitmap_fill(idxmsk, x86_pmu.num_events);
 }
 
 static int x86_event_sched_in(struct perf_event *event,