atomics: Provide atomic_add_negative() variants

atomic_add_negative() does not provide the relaxed/acquire/release
variants.

Provide them in preparation for a new scalable reference count algorithm.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20230323102800.101763813@linutronix.de

1 files changed, 199 insertions, 9 deletions

diff --git a/include/linux/atomic/atomic-arch-fallback.h b/include/linux/atomic/atomic-arch-fallback.h
index 77bc5522e61c..4226379a232d 100644
--- a/include/linux/atomic/atomic-arch-fallback.h
+++ b/include/linux/atomic/atomic-arch-fallback.h
@@ -1208,15 +1208,21 @@ arch_atomic_inc_and_test(atomic_t *v)
 #define arch_atomic_inc_and_test arch_atomic_inc_and_test
 #endif
 
+#ifndef arch_atomic_add_negative_relaxed
+#ifdef arch_atomic_add_negative
+#define arch_atomic_add_negative_acquire arch_atomic_add_negative
+#define arch_atomic_add_negative_release arch_atomic_add_negative
+#define arch_atomic_add_negative_relaxed arch_atomic_add_negative
+#endif /* arch_atomic_add_negative */
+
 #ifndef arch_atomic_add_negative
 /**
- * arch_atomic_add_negative - add and test if negative
+ * arch_atomic_add_negative - Add and test if negative
  * @i: integer value to add
  * @v: pointer of type atomic_t
  *
- * Atomically adds @i to @v and returns true
- * if the result is negative, or false when
- * result is greater than or equal to zero.
+ * Atomically adds @i to @v and returns true if the result is negative,
+ * or false when the result is greater than or equal to zero.
  */
 static __always_inline bool
 arch_atomic_add_negative(int i, atomic_t *v)
@@ -1226,6 +1232,95 @@ arch_atomic_add_negative(int i, atomic_t *v)
 #define arch_atomic_add_negative arch_atomic_add_negative
 #endif
 
+#ifndef arch_atomic_add_negative_acquire
+/**
+ * arch_atomic_add_negative_acquire - Add and test if negative
+ * @i: integer value to add
+ * @v: pointer of type atomic_t
+ *
+ * Atomically adds @i to @v and returns true if the result is negative,
+ * or false when the result is greater than or equal to zero.
+ */
+static __always_inline bool
+arch_atomic_add_negative_acquire(int i, atomic_t *v)
+{
+	return arch_atomic_add_return_acquire(i, v) < 0;
+}
+#define arch_atomic_add_negative_acquire arch_atomic_add_negative_acquire
+#endif
+
+#ifndef arch_atomic_add_negative_release
+/**
+ * arch_atomic_add_negative_release - Add and test if negative
+ * @i: integer value to add
+ * @v: pointer of type atomic_t
+ *
+ * Atomically adds @i to @v and returns true if the result is negative,
+ * or false when the result is greater than or equal to zero.
+ */
+static __always_inline bool
+arch_atomic_add_negative_release(int i, atomic_t *v)
+{
+	return arch_atomic_add_return_release(i, v) < 0;
+}
+#define arch_atomic_add_negative_release arch_atomic_add_negative_release
+#endif
+
+#ifndef arch_atomic_add_negative_relaxed
+/**
+ * arch_atomic_add_negative_relaxed - Add and test if negative
+ * @i: integer value to add
+ * @v: pointer of type atomic_t
+ *
+ * Atomically adds @i to @v and returns true if the result is negative,
+ * or false when the result is greater than or equal to zero.
+ */
+static __always_inline bool
+arch_atomic_add_negative_relaxed(int i, atomic_t *v)
+{
+	return arch_atomic_add_return_relaxed(i, v) < 0;
+}
+#define arch_atomic_add_negative_relaxed arch_atomic_add_negative_relaxed
+#endif
+
+#else /* arch_atomic_add_negative_relaxed */
+
+#ifndef arch_atomic_add_negative_acquire
+static __always_inline bool
+arch_atomic_add_negative_acquire(int i, atomic_t *v)
+{
+	bool ret = arch_atomic_add_negative_relaxed(i, v);
+	__atomic_acquire_fence();
+	return ret;
+}
+#define arch_atomic_add_negative_acquire arch_atomic_add_negative_acquire
+#endif
+
+#ifndef arch_atomic_add_negative_release
+static __always_inline bool
+arch_atomic_add_negative_release(int i, atomic_t *v)
+{
+	__atomic_release_fence();
+	return arch_atomic_add_negative_relaxed(i, v);
+}
+#define arch_atomic_add_negative_release arch_atomic_add_negative_release
+#endif
+
+#ifndef arch_atomic_add_negative
+static __always_inline bool
+arch_atomic_add_negative(int i, atomic_t *v)
+{
+	bool ret;
+	__atomic_pre_full_fence();
+	ret = arch_atomic_add_negative_relaxed(i, v);
+	__atomic_post_full_fence();
+	return ret;
+}
+#define arch_atomic_add_negative arch_atomic_add_negative
+#endif
+
+#endif /* arch_atomic_add_negative_relaxed */
+
 #ifndef arch_atomic_fetch_add_unless
 /**
  * arch_atomic_fetch_add_unless - add unless the number is already a given value
@@ -2329,15 +2424,21 @@ arch_atomic64_inc_and_test(atomic64_t *v)
 #define arch_atomic64_inc_and_test arch_atomic64_inc_and_test
 #endif
 
+#ifndef arch_atomic64_add_negative_relaxed
+#ifdef arch_atomic64_add_negative
+#define arch_atomic64_add_negative_acquire arch_atomic64_add_negative
+#define arch_atomic64_add_negative_release arch_atomic64_add_negative
+#define arch_atomic64_add_negative_relaxed arch_atomic64_add_negative
+#endif /* arch_atomic64_add_negative */
+
 #ifndef arch_atomic64_add_negative
 /**
- * arch_atomic64_add_negative - add and test if negative
+ * arch_atomic64_add_negative - Add and test if negative
  * @i: integer value to add
  * @v: pointer of type atomic64_t
  *
- * Atomically adds @i to @v and returns true
- * if the result is negative, or false when
- * result is greater than or equal to zero.
+ * Atomically adds @i to @v and returns true if the result is negative,
+ * or false when the result is greater than or equal to zero.
  */
 static __always_inline bool
 arch_atomic64_add_negative(s64 i, atomic64_t *v)
@@ -2347,6 +2448,95 @@ arch_atomic64_add_negative(s64 i, atomic64_t *v)
 #define arch_atomic64_add_negative arch_atomic64_add_negative
 #endif
 
+#ifndef arch_atomic64_add_negative_acquire
+/**
+ * arch_atomic64_add_negative_acquire - Add and test if negative
+ * @i: integer value to add
+ * @v: pointer of type atomic64_t
+ *
+ * Atomically adds @i to @v and returns true if the result is negative,
+ * or false when the result is greater than or equal to zero.
+ */
+static __always_inline bool
+arch_atomic64_add_negative_acquire(s64 i, atomic64_t *v)
+{
+	return arch_atomic64_add_return_acquire(i, v) < 0;
+}
+#define arch_atomic64_add_negative_acquire arch_atomic64_add_negative_acquire
+#endif
+
+#ifndef arch_atomic64_add_negative_release
+/**
+ * arch_atomic64_add_negative_release - Add and test if negative
+ * @i: integer value to add
+ * @v: pointer of type atomic64_t
+ *
+ * Atomically adds @i to @v and returns true if the result is negative,
+ * or false when the result is greater than or equal to zero.
+ */
+static __always_inline bool
+arch_atomic64_add_negative_release(s64 i, atomic64_t *v)
+{
+	return arch_atomic64_add_return_release(i, v) < 0;
+}
+#define arch_atomic64_add_negative_release arch_atomic64_add_negative_release
+#endif
+
+#ifndef arch_atomic64_add_negative_relaxed
+/**
+ * arch_atomic64_add_negative_relaxed - Add and test if negative
+ * @i: integer value to add
+ * @v: pointer of type atomic64_t
+ *
+ * Atomically adds @i to @v and returns true if the result is negative,
+ * or false when the result is greater than or equal to zero.
+ */
+static __always_inline bool
+arch_atomic64_add_negative_relaxed(s64 i, atomic64_t *v)
+{
+	return arch_atomic64_add_return_relaxed(i, v) < 0;
+}
+#define arch_atomic64_add_negative_relaxed arch_atomic64_add_negative_relaxed
+#endif
+
+#else /* arch_atomic64_add_negative_relaxed */
+
+#ifndef arch_atomic64_add_negative_acquire
+static __always_inline bool
+arch_atomic64_add_negative_acquire(s64 i, atomic64_t *v)
+{
+	bool ret = arch_atomic64_add_negative_relaxed(i, v);
+	__atomic_acquire_fence();
+	return ret;
+}
+#define arch_atomic64_add_negative_acquire arch_atomic64_add_negative_acquire
+#endif
+
+#ifndef arch_atomic64_add_negative_release
+static __always_inline bool
+arch_atomic64_add_negative_release(s64 i, atomic64_t *v)
+{
+	__atomic_release_fence();
+	return arch_atomic64_add_negative_relaxed(i, v);
+}
+#define arch_atomic64_add_negative_release arch_atomic64_add_negative_release
+#endif
+
+#ifndef arch_atomic64_add_negative
+static __always_inline bool
+arch_atomic64_add_negative(s64 i, atomic64_t *v)
+{
+	bool ret;
+	__atomic_pre_full_fence();
+	ret = arch_atomic64_add_negative_relaxed(i, v);
+	__atomic_post_full_fence();
+	return ret;
+}
+#define arch_atomic64_add_negative arch_atomic64_add_negative
+#endif
+
+#endif /* arch_atomic64_add_negative_relaxed */
+
 #ifndef arch_atomic64_fetch_add_unless
 /**
  * arch_atomic64_fetch_add_unless - add unless the number is already a given value
@@ -2456,4 +2646,4 @@ arch_atomic64_dec_if_positive(atomic64_t *v)
 #endif
 
 #endif /* _LINUX_ATOMIC_FALLBACK_H */
-// b5e87bdd5ede61470c29f7a7e4de781af3770f09
+// 00071fffa021cec66f6290d706d69c91df87bade