[PATCH 0/1] ARM: atomic64: fix endian-ness in atomic.h

Fixes atomic64_xxx functions endian-ness isussues as it was discussed on http://lists.infradead.org/pipermail/linux-arm-kernel/2013-July/185898.html Patch itself follows in separate email. This cover letter describes what testing has been done

Tested on pandaboard for both cases: LE and BE, CONFIG_GENERIC_ATOMIC64 was forcefully disabled.

In BE case it was tested on top of Ben's other BE patches covered by (updates for be8 patch series).

The following tests passed:

1) CONFIG_ATOMIC64_SELFTEST

2) The following module produced identical output for both LE, BE, and GENERIC_ATOMIC64

#include <linux/module.h> #include <linux/moduleparam.h> #include <linux/atomic.h>

atomic64_t a = {0};

#define STEP 0x40000000

void atomic64_add_test1 (void) { atomic64_add(STEP, &a); }

void test_atomic64_add(void) { int i;

printk("atomic64_add\n");

atomic64_set(&a, 0);

printk("a = 0x%llx (%lld)\n", a.counter, a.counter);

for (i = 0; i < 10; i++) { atomic64_add_test1(); printk("i = %2d: a = 0x%llx (%lld)\n", i, a.counter, a.counter); } }

void atomic64_sub_test1 (void) { atomic64_sub(STEP, &a); }

void test_atomic64_sub(void) { int i;

printk("atomic64_sub\n");

/* value of a is set by previos test */ printk("a = 0x%llx (%lld)\n", a.counter, a.counter);

for (i = 0; i < 20; i++) { atomic64_sub_test1(); printk("i = %2d: a = 0x%llx (%lld)\n", i, a.counter, a.counter); } }

u64 atomic64_add_return_test1 (void) { return atomic64_add_return(STEP, &a); }

void test_atomic64_add_return(void) { int i; u64 ret;

printk("atomic64_add_return\n");

atomic64_set(&a, 0);

printk("a = 0x%llx (%lld)\n", a.counter, a.counter);

for (i = 0; i < 10; i++) { ret = atomic64_add_return_test1(); printk("i = %2d: a = 0x%llx (%lld), ret = %llx (%lld)\n", i, a.counter, a.counter, ret, ret); } }

u64 atomic64_sub_return_test1 (void) { return atomic64_sub_return(STEP, &a); }

void test_atomic64_sub_return(void) { int i; u64 ret;

printk("atomic64_sub_return\n");

/* value of a is set by previos test */ printk("a = 0x%llx (%lld)\n", a.counter, a.counter);

for (i = 0; i < 20; i++) { ret = atomic64_sub_return_test1(); printk("i = %2d: a = 0x%llx (%lld), ret = %llx (%lld)\n", i, a.counter, a.counter, ret, ret); } }

void atomic64_dec_if_positive_test1 (void) { atomic64_dec_if_positive(&a); }

void test1_atomic64_dec_if_positive (void) { int i; printk("atomic64_dec_if_positive test1\n");

atomic64_set(&a, 0x100000003); /* value of a is set by previos test */ printk("a = 0x%llx (%lld)\n", a.counter, a.counter);

for (i = 0; i < 10; i++) { atomic64_dec_if_positive_test1(); printk("i = %2d: a = 0x%llx (%lld))\n", i, a.counter, a.counter); } }

void test2_atomic64_dec_if_positive (void) { int i; printk("atomic64_dec_if_positive test2\n");

atomic64_set(&a, 0x3); /* value of a is set by previos test */ printk("a = 0x%llx (%lld)\n", a.counter, a.counter);

for (i = 0; i < 10; i++) { atomic64_dec_if_positive_test1(); printk("i = %2d: a = 0x%llx (%lld))\n", i, a.counter, a.counter); } }

void atomic64_add_unless_test1(long long u) { atomic64_add_unless(&a, STEP, u); }

void test_atomic64_add_unless(void) { int i; u64 prev;

printk("atomic64_add_unless\n");

atomic64_set(&a, 0);

printk("a = 0x%llx (%lld)\n", a.counter, a.counter);

for (i = 0; i < 10; i++) { prev = a.counter; atomic64_add_unless_test1(prev); printk("i = %2d: no change: prev = 0x%llx (%lld), a = 0x%llx (%lld)\n", i, prev, prev, a.counter, a.counter); atomic64_add_unless_test1(prev - 1); printk("i = %2d: change: prev = 0x%llx (%lld), a = 0x%llx (%lld)\n", i, prev, prev, a.counter, a.counter); } }

int init_module (void) { test_atomic64_add(); test_atomic64_sub();

test_atomic64_add_return(); test_atomic64_sub_return();

test1_atomic64_dec_if_positive(); test2_atomic64_dec_if_positive();

test_atomic64_add_unless();

return 0; }

void cleanup_module(void) { }

MODULE_LICENSE("GPL");

Thanks, Victor

Victor Kamensky (1): ARM: atomic64: fix endian-ness in atomic.h

arch/arm/include/asm/atomic.h | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-)