[PATCH 1/3] kasan: deduplicate quarantine reduction logic

[Igor Putko <igorpetindev@gmail.com>]

Multiple allocation functions share the exact same conditional logic for
reducing the KASAN quarantine size based on gfp flags.
Introduce the kasan_quarantine_reduce_cond() helper to eliminate this
boilerplate from the slab, kmalloc, kmalloc_large, and krealloc paths.

Signed-off-by: Igor Putko <igorpetindev@gmail.com>
---
 mm/kasan/common.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/mm/kasan/common.c b/mm/kasan/common.c
index b7d05c2a6..34aa0fdce 100644
--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -340,14 +340,19 @@ static inline void unpoison_slab_object(struct kmem_cache *cache, void *object,
 		kasan_save_alloc_info(cache, object, flags);
 }
 
+static inline void kasan_quarantine_reduce_cond(gfp_t flags)
+{
+	if (gfpflags_allow_blocking(flags))
+		kasan_quarantine_reduce();
+}
+
 void * __must_check __kasan_slab_alloc(struct kmem_cache *cache,
 					void *object, gfp_t flags, bool init)
 {
 	u8 tag;
 	void *tagged_object;
 
-	if (gfpflags_allow_blocking(flags))
-		kasan_quarantine_reduce();
+	kasan_quarantine_reduce_cond(flags);
 
 	if (unlikely(object == NULL))
 		return NULL;
@@ -402,8 +407,7 @@ static inline void poison_kmalloc_redzone(struct kmem_cache *cache,
 void * __must_check __kasan_kmalloc(struct kmem_cache *cache, const void *object,
 					size_t size, gfp_t flags)
 {
-	if (gfpflags_allow_blocking(flags))
-		kasan_quarantine_reduce();
+	kasan_quarantine_reduce_cond(flags);
 
 	if (unlikely(object == NULL))
 		return NULL;
@@ -443,8 +447,7 @@ static inline void poison_kmalloc_large_redzone(const void *ptr, size_t size,
 void * __must_check __kasan_kmalloc_large(const void *ptr, size_t size,
 						gfp_t flags)
 {
-	if (gfpflags_allow_blocking(flags))
-		kasan_quarantine_reduce();
+	kasan_quarantine_reduce_cond(flags);
 
 	if (unlikely(ptr == NULL))
 		return NULL;
@@ -460,8 +463,7 @@ void * __must_check __kasan_krealloc(const void *object, size_t size, gfp_t flag
 {
 	struct slab *slab;
 
-	if (gfpflags_allow_blocking(flags))
-		kasan_quarantine_reduce();
+	kasan_quarantine_reduce_cond(flags);
 
 	if (unlikely(object == ZERO_SIZE_PTR))
 		return (void *)object;
-- 
2.47.3