[PATCH] arm_mpam: make the mon_sel_lock guard return -EIO

[Ping Li]

The mon_sel_lock guard class reports -EBUSY when the lock cannot be
taken, but every other failure path of mpam_mon_sel_lock() returns
-EIO.

Encode the error with ERR_PTR(-EIO) in the guard class, so that
ACQUIRE_ERR() reports -EIO as well.

Suggested-by: Ben Horgan <ben.horgan@xxxxxxx>
Signed-off-by: Ping Li <leeonion.muyu@xxxxxxxxx>
---
 drivers/resctrl/mpam_internal.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/resctrl/mpam_internal.h b/drivers/resctrl/mpam_internal.h
index 1f86cc158100..2f6dfb9d3906 100644
--- a/drivers/resctrl/mpam_internal.h
+++ b/drivers/resctrl/mpam_internal.h
@@ -204,8 +204,8 @@ static inline int mpam_mon_sel_lock_init(struct device *dev,
 }
 
 DEFINE_CLASS(mon_sel_lock, struct mpam_msc *,
-	     if (_T) mpam_mon_sel_unlock(_T),
-	     mpam_mon_sel_lock(msc) ? msc : NULL, struct mpam_msc *msc);
+	     if (_T && !IS_ERR(_T)) mpam_mon_sel_unlock(_T),
+	     mpam_mon_sel_lock(msc) ? msc : ERR_PTR(-EIO), struct mpam_msc *msc);
 DEFINE_CLASS_IS_COND_GUARD(mon_sel_lock);
 
 /* Bits for mpam features bitmaps */

base-commit: 8ea457f746d915d55f78b43d33b1cd618f3d93ad
-- 
2.34.1