Currently architecture must implement atomic_fetch_add_unless(), with
common code providing atomic_add_unless(). Architectures must also
implement atmic64_add_unless() directly, with no corresponding
atomic64_fetch_add_unless().
This divergenece is unfortunate, and means that the APIs for atomic_t,
atomic64_t, and atomic_long_t differ.
In preparation for unifying things, with architectures providing
atomic64_fetch_add_unless, this patch adds a generic
atomic64_add_unless() which will use atomic64_fetch_add_unless(). The
instrumented atomics are updated to take this case into account.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutl...@arm.com>
Cc: Boqun Feng <boqun.f...@gmail.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Will Deacon <will.dea...@arm.com>
Cc: Arnd Bergmann <a...@arndb.de>
Cc: Richard Henderson <r...@twiddle.net>
Cc: Ivan Kokshaysky <i...@jurassic.park.msu.ru>
Cc: Matt Turner <matts...@gmail.com>
Cc: Vineet Gupta <vgu...@synopsys.com>
Cc: Russell King <li...@armlinux.org.uk>
Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: Paul Mackerras <pau...@samba.org>
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: Palmer Dabbelt <pal...@sifive.com>
Cc: Albert Ou <alb...@sifive.com>
---
include/asm-generic/atomic-instrumented.h | 9 +++++++++
include/linux/atomic.h | 16 ++++++++++++++++
2 files changed, 25 insertions(+)
diff --git a/include/asm-generic/atomic-instrumented.h
b/include/asm-generic/atomic-instrumented.h
index 6e0818c182e2..e22d7e5f4ce7 100644
--- a/include/asm-generic/atomic-instrumented.h
+++ b/include/asm-generic/atomic-instrumented.h
@@ -93,11 +93,20 @@ static __always_inline int atomic_fetch_add_unless(atomic_t
*v, int a, int u)
}
#endif
+#ifdef arch_atomic64_fetch_add_unless
+#define atomic64_fetch_add_unless atomic64_fetch_add_unless
+static __always_inline int atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64
u)
+{
+ kasan_check_write(v, sizeof(*v));
+ return arch_atomic64_fetch_add_unless(v, a, u);
+}
+#else
static __always_inline bool atomic64_add_unless(atomic64_t *v, s64 a, s64 u)
{
kasan_check_write(v, sizeof(*v));
return arch_atomic64_add_unless(v, a, u);
}
+#endif
static __always_inline void atomic_inc(atomic_t *v)
{
diff --git a/include/linux/atomic.h b/include/linux/atomic.h
index 1105c0b37f27..8d93209052e1 100644
--- a/include/linux/atomic.h
+++ b/include/linux/atomic.h
@@ -1072,6 +1072,22 @@ static inline int atomic_dec_if_positive(atomic_t *v)
#endif /* atomic64_try_cmpxchg */
/**
+ * atomic64_add_unless - add unless the number is already a given value
+ * @v: pointer of type atomic_t
+ * @a: the amount to add to v...
+ * @u: ...unless v is equal to u.
+ *
+ * Atomically adds @a to @v, so long as @v was not already @u.
+ * Returns non-zero if @v was not @u, and zero otherwise.
+ */
+#ifdef atomic64_fetch_add_unless
+static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u)
+{
+ return atomic64_fetch_add_unless(v, a, u) != u;
+}
+#endif
+
+/**
* atomic64_inc_not_zero - increment unless the number is zero
* @v: pointer of type atomic64_t
*
--
2.11.0
