forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
139 lines
3.2 KiB
139 lines
3.2 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
#include <linux/module.h> |
|
|
|
/* validate @native and @pcp counter values match @expected */ |
|
#define CHECK(native, pcp, expected) \ |
|
do { \ |
|
WARN((native) != (expected), \ |
|
"raw %ld (0x%lx) != expected %lld (0x%llx)", \ |
|
(native), (native), \ |
|
(long long)(expected), (long long)(expected)); \ |
|
WARN(__this_cpu_read(pcp) != (expected), \ |
|
"pcp %ld (0x%lx) != expected %lld (0x%llx)", \ |
|
__this_cpu_read(pcp), __this_cpu_read(pcp), \ |
|
(long long)(expected), (long long)(expected)); \ |
|
} while (0) |
|
|
|
static DEFINE_PER_CPU(long, long_counter); |
|
static DEFINE_PER_CPU(unsigned long, ulong_counter); |
|
|
|
static int __init percpu_test_init(void) |
|
{ |
|
/* |
|
* volatile prevents compiler from optimizing it uses, otherwise the |
|
* +ul_one/-ul_one below would replace with inc/dec instructions. |
|
*/ |
|
volatile unsigned int ui_one = 1; |
|
long l = 0; |
|
unsigned long ul = 0; |
|
|
|
pr_info("percpu test start\n"); |
|
|
|
preempt_disable(); |
|
|
|
l += -1; |
|
__this_cpu_add(long_counter, -1); |
|
CHECK(l, long_counter, -1); |
|
|
|
l += 1; |
|
__this_cpu_add(long_counter, 1); |
|
CHECK(l, long_counter, 0); |
|
|
|
ul = 0; |
|
__this_cpu_write(ulong_counter, 0); |
|
|
|
ul += 1UL; |
|
__this_cpu_add(ulong_counter, 1UL); |
|
CHECK(ul, ulong_counter, 1); |
|
|
|
ul += -1UL; |
|
__this_cpu_add(ulong_counter, -1UL); |
|
CHECK(ul, ulong_counter, 0); |
|
|
|
ul += -(unsigned long)1; |
|
__this_cpu_add(ulong_counter, -(unsigned long)1); |
|
CHECK(ul, ulong_counter, -1); |
|
|
|
ul = 0; |
|
__this_cpu_write(ulong_counter, 0); |
|
|
|
ul -= 1; |
|
__this_cpu_dec(ulong_counter); |
|
CHECK(ul, ulong_counter, -1); |
|
CHECK(ul, ulong_counter, ULONG_MAX); |
|
|
|
l += -ui_one; |
|
__this_cpu_add(long_counter, -ui_one); |
|
CHECK(l, long_counter, 0xffffffff); |
|
|
|
l += ui_one; |
|
__this_cpu_add(long_counter, ui_one); |
|
CHECK(l, long_counter, (long)0x100000000LL); |
|
|
|
|
|
l = 0; |
|
__this_cpu_write(long_counter, 0); |
|
|
|
l -= ui_one; |
|
__this_cpu_sub(long_counter, ui_one); |
|
CHECK(l, long_counter, -1); |
|
|
|
l = 0; |
|
__this_cpu_write(long_counter, 0); |
|
|
|
l += ui_one; |
|
__this_cpu_add(long_counter, ui_one); |
|
CHECK(l, long_counter, 1); |
|
|
|
l += -ui_one; |
|
__this_cpu_add(long_counter, -ui_one); |
|
CHECK(l, long_counter, (long)0x100000000LL); |
|
|
|
l = 0; |
|
__this_cpu_write(long_counter, 0); |
|
|
|
l -= ui_one; |
|
this_cpu_sub(long_counter, ui_one); |
|
CHECK(l, long_counter, -1); |
|
CHECK(l, long_counter, ULONG_MAX); |
|
|
|
ul = 0; |
|
__this_cpu_write(ulong_counter, 0); |
|
|
|
ul += ui_one; |
|
__this_cpu_add(ulong_counter, ui_one); |
|
CHECK(ul, ulong_counter, 1); |
|
|
|
ul = 0; |
|
__this_cpu_write(ulong_counter, 0); |
|
|
|
ul -= ui_one; |
|
__this_cpu_sub(ulong_counter, ui_one); |
|
CHECK(ul, ulong_counter, -1); |
|
CHECK(ul, ulong_counter, ULONG_MAX); |
|
|
|
ul = 3; |
|
__this_cpu_write(ulong_counter, 3); |
|
|
|
ul = this_cpu_sub_return(ulong_counter, ui_one); |
|
CHECK(ul, ulong_counter, 2); |
|
|
|
ul = __this_cpu_sub_return(ulong_counter, ui_one); |
|
CHECK(ul, ulong_counter, 1); |
|
|
|
preempt_enable(); |
|
|
|
pr_info("percpu test done\n"); |
|
return -EAGAIN; /* Fail will directly unload the module */ |
|
} |
|
|
|
static void __exit percpu_test_exit(void) |
|
{ |
|
} |
|
|
|
module_init(percpu_test_init) |
|
module_exit(percpu_test_exit) |
|
|
|
MODULE_LICENSE("GPL"); |
|
MODULE_AUTHOR("Greg Thelen"); |
|
MODULE_DESCRIPTION("percpu operations test");
|
|
|