diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/lib/percpu_test.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/lib/percpu_test.c')
-rw-r--r-- | kernel/lib/percpu_test.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/kernel/lib/percpu_test.c b/kernel/lib/percpu_test.c new file mode 100644 index 000000000..0b5d14dad --- /dev/null +++ b/kernel/lib/percpu_test.c @@ -0,0 +1,138 @@ +#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"); |