From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>,
x86@kernel.org, Wangyang Guo <wangyang.guo@intel.com>,
Arjan van De Ven <arjan@linux.intel.com>,
"David S. Miller" <davem@davemloft.net>,
Eric Dumazet <edumazet@google.com>,
Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
netdev@vger.kernel.org, Will Deacon <will@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Boqun Feng <boqun.feng@gmail.com>,
Mark Rutland <mark.rutland@arm.com>,
Marc Zyngier <maz@kernel.org>, Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Subject: [patch V3 2/4] atomics: Provide atomic_add_negative() variants
Date: Thu, 23 Mar 2023 21:55:30 +0100 (CET) [thread overview]
Message-ID: <20230323102800.101763813@linutronix.de> (raw)
In-Reply-To: <20230323102649.764958589@linutronix.de>
From: Thomas Gleixner <tglx@linutronix.de>
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>
Acked-by: Mark Rutland <mark.rutland@arm.com>
---
V3: Fix typos (Mark). Make kernel doc correct vs. ordering variants
V2: New patch
---
include/linux/atomic/atomic-arch-fallback.h | 208 ++++++++++++++++++++++++++--
include/linux/atomic/atomic-instrumented.h | 68 +++++++++
include/linux/atomic/atomic-long.h | 38 ++++-
scripts/atomic/atomics.tbl | 2
scripts/atomic/fallbacks/add_negative | 11 -
5 files changed, 309 insertions(+), 18 deletions(-)
--- 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
#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, atomic
#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
#endif
#endif /* _LINUX_ATOMIC_FALLBACK_H */
-// b5e87bdd5ede61470c29f7a7e4de781af3770f09
+// 00071fffa021cec66f6290d706d69c91df87bade
--- a/include/linux/atomic/atomic-instrumented.h
+++ b/include/linux/atomic/atomic-instrumented.h
@@ -592,6 +592,28 @@ atomic_add_negative(int i, atomic_t *v)
return arch_atomic_add_negative(i, v);
}
+static __always_inline bool
+atomic_add_negative_acquire(int i, atomic_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_add_negative_acquire(i, v);
+}
+
+static __always_inline bool
+atomic_add_negative_release(int i, atomic_t *v)
+{
+ kcsan_release();
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_add_negative_release(i, v);
+}
+
+static __always_inline bool
+atomic_add_negative_relaxed(int i, atomic_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_add_negative_relaxed(i, v);
+}
+
static __always_inline int
atomic_fetch_add_unless(atomic_t *v, int a, int u)
{
@@ -1211,6 +1233,28 @@ atomic64_add_negative(s64 i, atomic64_t
return arch_atomic64_add_negative(i, v);
}
+static __always_inline bool
+atomic64_add_negative_acquire(s64 i, atomic64_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic64_add_negative_acquire(i, v);
+}
+
+static __always_inline bool
+atomic64_add_negative_release(s64 i, atomic64_t *v)
+{
+ kcsan_release();
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic64_add_negative_release(i, v);
+}
+
+static __always_inline bool
+atomic64_add_negative_relaxed(s64 i, atomic64_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic64_add_negative_relaxed(i, v);
+}
+
static __always_inline s64
atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u)
{
@@ -1830,6 +1874,28 @@ atomic_long_add_negative(long i, atomic_
return arch_atomic_long_add_negative(i, v);
}
+static __always_inline bool
+atomic_long_add_negative_acquire(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_add_negative_acquire(i, v);
+}
+
+static __always_inline bool
+atomic_long_add_negative_release(long i, atomic_long_t *v)
+{
+ kcsan_release();
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_add_negative_release(i, v);
+}
+
+static __always_inline bool
+atomic_long_add_negative_relaxed(long i, atomic_long_t *v)
+{
+ instrument_atomic_read_write(v, sizeof(*v));
+ return arch_atomic_long_add_negative_relaxed(i, v);
+}
+
static __always_inline long
atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u)
{
@@ -2083,4 +2149,4 @@ atomic_long_dec_if_positive(atomic_long_
})
#endif /* _LINUX_ATOMIC_INSTRUMENTED_H */
-// 764f741eb77a7ad565dc8d99ce2837d5542e8aee
+// 1b485de9cbaa4900de59e14ee2084357eaeb1c3a
--- a/include/linux/atomic/atomic-long.h
+++ b/include/linux/atomic/atomic-long.h
@@ -479,6 +479,24 @@ arch_atomic_long_add_negative(long i, at
return arch_atomic64_add_negative(i, v);
}
+static __always_inline bool
+arch_atomic_long_add_negative_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic64_add_negative_acquire(i, v);
+}
+
+static __always_inline bool
+arch_atomic_long_add_negative_release(long i, atomic_long_t *v)
+{
+ return arch_atomic64_add_negative_release(i, v);
+}
+
+static __always_inline bool
+arch_atomic_long_add_negative_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic64_add_negative_relaxed(i, v);
+}
+
static __always_inline long
arch_atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u)
{
@@ -973,6 +991,24 @@ arch_atomic_long_add_negative(long i, at
return arch_atomic_add_negative(i, v);
}
+static __always_inline bool
+arch_atomic_long_add_negative_acquire(long i, atomic_long_t *v)
+{
+ return arch_atomic_add_negative_acquire(i, v);
+}
+
+static __always_inline bool
+arch_atomic_long_add_negative_release(long i, atomic_long_t *v)
+{
+ return arch_atomic_add_negative_release(i, v);
+}
+
+static __always_inline bool
+arch_atomic_long_add_negative_relaxed(long i, atomic_long_t *v)
+{
+ return arch_atomic_add_negative_relaxed(i, v);
+}
+
static __always_inline long
arch_atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u)
{
@@ -1011,4 +1047,4 @@ arch_atomic_long_dec_if_positive(atomic_
#endif /* CONFIG_64BIT */
#endif /* _LINUX_ATOMIC_LONG_H */
-// e8f0e08ff072b74d180eabe2ad001282b38c2c88
+// a194c07d7d2f4b0e178d3c118c919775d5d65f50
--- a/scripts/atomic/atomics.tbl
+++ b/scripts/atomic/atomics.tbl
@@ -33,7 +33,7 @@ try_cmpxchg B v p:old i:new
sub_and_test b i v
dec_and_test b v
inc_and_test b v
-add_negative b i v
+add_negative B i v
add_unless fb v i:a i:u
inc_not_zero b v
inc_unless_negative b v
--- a/scripts/atomic/fallbacks/add_negative
+++ b/scripts/atomic/fallbacks/add_negative
@@ -1,16 +1,15 @@
cat <<EOF
/**
- * arch_${atomic}_add_negative - add and test if negative
+ * arch_${atomic}_add_negative${order} - 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, ${atomic}_t *v)
+arch_${atomic}_add_negative${order}(${int} i, ${atomic}_t *v)
{
- return arch_${atomic}_add_return(i, v) < 0;
+ return arch_${atomic}_add_return${order}(i, v) < 0;
}
EOF
next prev parent reply other threads:[~2023-03-23 20:55 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-23 20:55 [patch V3 0/4] net, refcount: Address dst_entry reference count scalability issues Thomas Gleixner
2023-03-23 20:55 ` [patch V3 1/4] [patch V2 1/4] net: dst: Prevent false sharing vs. dst_entry:: __refcnt Thomas Gleixner
2023-03-23 20:55 ` Thomas Gleixner [this message]
2023-03-28 8:49 ` [tip: locking/core] atomics: Provide atomic_add_negative() variants tip-bot2 for Thomas Gleixner
2023-04-29 7:03 ` tip-bot2 for Thomas Gleixner
2023-03-23 20:55 ` [patch V3 3/4] atomics: Provide rcuref - scalable reference counting Thomas Gleixner
2023-03-28 8:49 ` [tip: locking/core] " tip-bot2 for Thomas Gleixner
2023-04-29 7:03 ` tip-bot2 for Thomas Gleixner
2023-03-23 20:55 ` [patch V3 4/4] net: dst: Switch to rcuref_t " Thomas Gleixner
2023-03-23 21:54 ` Linus Torvalds
2023-03-28 8:45 ` [patch V3 0/4] net, refcount: Address dst_entry reference count scalability issues Peter Zijlstra
2023-03-29 2:30 ` patchwork-bot+netdevbpf
2023-04-10 22:53 ` Paul E. McKenney
2023-04-17 11:44 ` Leon Romanovsky
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