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authorLinus Torvalds <torvalds@linux-foundation.org>2010-05-18 08:40:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-18 08:40:05 -0700
commit93c9d7f60c0cb7715890b1f9e159da6f4d1f5a65 (patch)
tree6be428ca5fe52f14ebb78a8e695cec59d2f21c26 /lib
parent7421a10de7a525f67cc082fca7a91011d00eada4 (diff)
parentd9c5841e22231e4e49fd0a1004164e6fce59b7a6 (diff)
Merge branch 'x86-atomic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-atomic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Fix LOCK_PREFIX_HERE for uniprocessor build x86, atomic64: In selftest, distinguish x86-64 from 586+ x86-32: Fix atomic64_inc_not_zero return value convention lib: Fix atomic64_inc_not_zero test lib: Fix atomic64_add_unless return value convention x86-32: Fix atomic64_add_unless return value convention lib: Fix atomic64_add_unless test x86: Implement atomic[64]_dec_if_positive() lib: Only test atomic64_dec_if_positive on archs having it x86-32: Rewrite 32-bit atomic64 functions in assembly lib: Add self-test for atomic64_t x86-32: Allow UP/SMP lock replacement in cmpxchg64 x86: Add support for lock prefix in alternatives
Diffstat (limited to 'lib')
-rw-r--r--lib/Kconfig.debug7
-rw-r--r--lib/Makefile2
-rw-r--r--lib/atomic64.c4
-rw-r--r--lib/atomic64_test.c164
4 files changed, 175 insertions, 2 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 930a9e5eae0..d85be90d588 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1098,6 +1098,13 @@ config DMA_API_DEBUG
This option causes a performance degredation. Use only if you want
to debug device drivers. If unsure, say N.
+config ATOMIC64_SELFTEST
+ bool "Perform an atomic64_t self-test at boot"
+ help
+ Enable this option to test the atomic64_t functions at boot.
+
+ If unsure, say N.
+
source "samples/Kconfig"
source "lib/Kconfig.kgdb"
diff --git a/lib/Makefile b/lib/Makefile
index 0d4015205c6..af759f39d4a 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -101,6 +101,8 @@ obj-$(CONFIG_GENERIC_CSUM) += checksum.o
obj-$(CONFIG_GENERIC_ATOMIC64) += atomic64.o
+obj-$(CONFIG_ATOMIC64_SELFTEST) += atomic64_test.o
+
hostprogs-y := gen_crc32table
clean-files := crc32table.h
diff --git a/lib/atomic64.c b/lib/atomic64.c
index 8bee16ec752..a21c12bc727 100644
--- a/lib/atomic64.c
+++ b/lib/atomic64.c
@@ -162,12 +162,12 @@ int atomic64_add_unless(atomic64_t *v, long long a, long long u)
{
unsigned long flags;
spinlock_t *lock = lock_addr(v);
- int ret = 1;
+ int ret = 0;
spin_lock_irqsave(lock, flags);
if (v->counter != u) {
v->counter += a;
- ret = 0;
+ ret = 1;
}
spin_unlock_irqrestore(lock, flags);
return ret;
diff --git a/lib/atomic64_test.c b/lib/atomic64_test.c
new file mode 100644
index 00000000000..65e482caf5e
--- /dev/null
+++ b/lib/atomic64_test.c
@@ -0,0 +1,164 @@
+/*
+ * Testsuite for atomic64_t functions
+ *
+ * Copyright © 2010 Luca Barbieri
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+#include <linux/init.h>
+#include <asm/atomic.h>
+
+#define INIT(c) do { atomic64_set(&v, c); r = c; } while (0)
+static __init int test_atomic64(void)
+{
+ long long v0 = 0xaaa31337c001d00dLL;
+ long long v1 = 0xdeadbeefdeafcafeLL;
+ long long v2 = 0xfaceabadf00df001LL;
+ long long onestwos = 0x1111111122222222LL;
+ long long one = 1LL;
+
+ atomic64_t v = ATOMIC64_INIT(v0);
+ long long r = v0;
+ BUG_ON(v.counter != r);
+
+ atomic64_set(&v, v1);
+ r = v1;
+ BUG_ON(v.counter != r);
+ BUG_ON(atomic64_read(&v) != r);
+
+ INIT(v0);
+ atomic64_add(onestwos, &v);
+ r += onestwos;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ atomic64_add(-one, &v);
+ r += -one;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r += onestwos;
+ BUG_ON(atomic64_add_return(onestwos, &v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r += -one;
+ BUG_ON(atomic64_add_return(-one, &v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ atomic64_sub(onestwos, &v);
+ r -= onestwos;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ atomic64_sub(-one, &v);
+ r -= -one;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r -= onestwos;
+ BUG_ON(atomic64_sub_return(onestwos, &v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r -= -one;
+ BUG_ON(atomic64_sub_return(-one, &v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ atomic64_inc(&v);
+ r += one;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r += one;
+ BUG_ON(atomic64_inc_return(&v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ atomic64_dec(&v);
+ r -= one;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r -= one;
+ BUG_ON(atomic64_dec_return(&v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ BUG_ON(atomic64_xchg(&v, v1) != v0);
+ r = v1;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ BUG_ON(atomic64_cmpxchg(&v, v0, v1) != v0);
+ r = v1;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ BUG_ON(atomic64_cmpxchg(&v, v2, v1) != v0);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ BUG_ON(atomic64_add_unless(&v, one, v0));
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ BUG_ON(!atomic64_add_unless(&v, one, v1));
+ r += one;
+ BUG_ON(v.counter != r);
+
+#if defined(CONFIG_X86) || defined(CONFIG_MIPS) || defined(CONFIG_PPC) || defined(_ASM_GENERIC_ATOMIC64_H)
+ INIT(onestwos);
+ BUG_ON(atomic64_dec_if_positive(&v) != (onestwos - 1));
+ r -= one;
+ BUG_ON(v.counter != r);
+
+ INIT(0);
+ BUG_ON(atomic64_dec_if_positive(&v) != -one);
+ BUG_ON(v.counter != r);
+
+ INIT(-one);
+ BUG_ON(atomic64_dec_if_positive(&v) != (-one - one));
+ BUG_ON(v.counter != r);
+#else
+#warning Please implement atomic64_dec_if_positive for your architecture, and add it to the IF above
+#endif
+
+ INIT(onestwos);
+ BUG_ON(!atomic64_inc_not_zero(&v));
+ r += one;
+ BUG_ON(v.counter != r);
+
+ INIT(0);
+ BUG_ON(atomic64_inc_not_zero(&v));
+ BUG_ON(v.counter != r);
+
+ INIT(-one);
+ BUG_ON(!atomic64_inc_not_zero(&v));
+ r += one;
+ BUG_ON(v.counter != r);
+
+#ifdef CONFIG_X86
+ printk(KERN_INFO "atomic64 test passed for %s platform %s CX8 and %s SSE\n",
+#ifdef CONFIG_X86_64
+ "x86-64",
+#elif defined(CONFIG_X86_CMPXCHG64)
+ "i586+",
+#else
+ "i386+",
+#endif
+ boot_cpu_has(X86_FEATURE_CX8) ? "with" : "without",
+ boot_cpu_has(X86_FEATURE_XMM) ? "with" : "without");
+#else
+ printk(KERN_INFO "atomic64 test passed\n");
+#endif
+
+ return 0;
+}
+
+core_initcall(test_atomic64);