[PATCH v6 4/9] rv: Fix ha_invariant_passed_ns silent bypass of invariant check

[wen . yang]

From: Wen Yang <wen.yang@xxxxxxxxx>

When env_store is U64_MAX (its initial sentinel value),
ha_invariant_passed_ns() returns 0 immediately without initializing
env_store to the current clock.  Subsequent calls to
ha_check_invariant_ns() then find env_store still at U64_MAX, causing
the elapsed comparison to wrap and always report the invariant as
satisfied, silently masking any violations.

Fix by calling ha_reset_clk_ns() to establish the guard on the first
invocation instead of returning early.  Apply the same fix to
ha_invariant_passed_jiffy().

This is a stopgap: once the RV framework reworks the per-env clock
guard, this first-invocation reset should be subsumed.

Signed-off-by: Wen Yang <wen.yang@xxxxxxxxx>
---
 include/rv/ha_monitor.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/include/rv/ha_monitor.h b/include/rv/ha_monitor.h
index 6e1c7fe5449a..e1738d199b28 100644
--- a/include/rv/ha_monitor.h
+++ b/include/rv/ha_monitor.h
@@ -355,7 +355,7 @@ static inline u64 ha_invariant_passed_ns(struct ha_monitor *ha_mon, enum envs en
 	if (env < 0 || env >= ENV_MAX_STORED)
 		return 0;
 	if (ha_monitor_env_invalid(ha_mon, env))
-		return 0;
+		ha_reset_clk_ns(ha_mon, env, time_ns);
 	return ha_get_env(ha_mon, env, time_ns);
 }
 
@@ -375,6 +375,7 @@ static inline bool ha_check_invariant_jiffy(struct ha_monitor *ha_mon, enum envs
 {
 	return time_after64(READ_ONCE(ha_mon->env_store[env]), get_jiffies_64() - expire_jiffy);
 }
+
 /*
  * ha_invariant_passed_jiffy - prepare the invariant and return the time since reset
  */
@@ -383,7 +384,7 @@ static inline u64 ha_invariant_passed_jiffy(struct ha_monitor *ha_mon, enum envs
 	if (env < 0 || env >= ENV_MAX_STORED)
 		return 0;
 	if (ha_monitor_env_invalid(ha_mon, env))
-		return 0;
+		ha_reset_clk_jiffy(ha_mon, env);
 	return ha_get_env(ha_mon, env, time_ns);
 }
 
-- 
2.25.1