[PATCH 4/8] perf/arm-cmn: Improve build-time assertions

[Robin Murphy]

These days we can use static_assert() in the logical place rather than
jamming a BUILD_BUG_ON() into the nearest function scope. And since it
is now so convenient to do so, let's add an extra one to reinforce the
dtm_idx bitmap as well.

Signed-off-by: Robin Murphy <robin.murphy at arm.com>
---
 drivers/perf/arm-cmn.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c
index c9a2b21a7aec..8f7a1a6f8ab7 100644
--- a/drivers/perf/arm-cmn.c
+++ b/drivers/perf/arm-cmn.c
@@ -577,6 +577,9 @@ struct arm_cmn_hw_event {
 	bool wide_sel;
 	enum cmn_filter_select filter_sel;
 };
+static_assert(sizeof(struct arm_cmn_hw_event) <= offsetof(struct hw_perf_event, target));
+/* Currently XPs are the node type we can have most of; others top out at 128 */
+static_assert(sizeof_field(struct arm_cmn_hw_event, dtm_idx) >= CMN_MAX_XPS / 4);
 
 #define for_each_hw_dn(hw, dn, i) \
 	for (i = 0, dn = hw->dn; i < hw->num_dns; i++, dn++)
@@ -587,7 +590,6 @@ struct arm_cmn_hw_event {
 
 static struct arm_cmn_hw_event *to_cmn_hw(struct perf_event *event)
 {
-	BUILD_BUG_ON(sizeof(struct arm_cmn_hw_event) > offsetof(struct hw_perf_event, target));
 	return (struct arm_cmn_hw_event *)&event->hw;
 }
 
-- 
2.39.2.101.g768bb238c484.dirty