[RFC 02/12] powerpc/pseries: Rework hugepage invalidate to remove conditional locking

[Ritesh Harjani (IBM)]

Clang's compiler based static context analysis does not work with locks
that are conditionally taken like in __pSeries_lpar_hugepage_invalidate().

lpar.c:1240:6: error: spinlock 'pSeries_lpar_tlbie_lock' is not held on every path through here [-Werror,-Wthread-safety-analysis]

But this also simplifies the function definition in my opinion - so this
is also a win.

No functional change intended.

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>
---
 arch/powerpc/platforms/pseries/lpar.c | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
index 94cd30e9f6e1..abd77c45cbf4 100644
--- a/arch/powerpc/platforms/pseries/lpar.c
+++ b/arch/powerpc/platforms/pseries/lpar.c
@@ -1224,26 +1224,33 @@ static void hugepage_bulk_invalidate(unsigned long *slot, unsigned long *vpn,
 		BUG_ON(rc != H_SUCCESS);
 	}
 }
-
-static void __pSeries_lpar_hugepage_invalidate(unsigned long *slot,
+static void __pSeries_lpar_hugepage_invalidate_unlocked(unsigned long *slot,
 						      unsigned long *vpn,
 						      int count, int psize,
 						      int ssize)
 {
-	unsigned long flags = 0;
-	int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
-
-	if (lock_tlbie)
-		spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);
-
 	/* Assuming THP size is 16M */
 	if (is_supported_hlbkrm(psize, MMU_PAGE_16M))
 		hugepage_block_invalidate(slot, vpn, count, psize, ssize);
 	else
 		hugepage_bulk_invalidate(slot, vpn, count, psize, ssize);
+}
 
-	if (lock_tlbie)
+static void __pSeries_lpar_hugepage_invalidate(unsigned long *slot,
+						      unsigned long *vpn,
+						      int count, int psize,
+						      int ssize)
+{
+	unsigned long flags = 0;
+
+	if (!mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE)) {
+		spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);
+		__pSeries_lpar_hugepage_invalidate_unlocked(slot, vpn, count, psize, ssize);
 		spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
+		return;
+	}
+
+	__pSeries_lpar_hugepage_invalidate_unlocked(slot, vpn, count, psize, ssize);
 }
 
 static void pSeries_lpar_hugepage_invalidate(unsigned long vsid,
-- 
2.39.5