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| author | Hans Petter Selasky <hselasky@FreeBSD.org> | 2018-08-06 08:40:02 +0000 |
|---|---|---|
| committer | Hans Petter Selasky <hselasky@FreeBSD.org> | 2018-08-06 08:40:02 +0000 |
| commit | db119089beb7c616722f7e5265a55cecb9c84f12 (patch) | |
| tree | 9e759d07999648f3e96081f0e73018edd4d03069 /sys | |
| parent | f698bc4d767c5840c2c21a0df68aadaa05c186ba (diff) | |
| download | src-db119089beb7c616722f7e5265a55cecb9c84f12.tar.gz src-db119089beb7c616722f7e5265a55cecb9c84f12.zip | |
Implement atomic_long_cmpxchg() function in the LinuxKPI.
Submitted by: Johannes Lundberg <johalun0@gmail.com>
MFC after: 1 week
Sponsored by: Mellanox Technologies
Notes
Notes:
svn path=/head/; revision=337374
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/compat/linuxkpi/common/include/asm/atomic-long.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/sys/compat/linuxkpi/common/include/asm/atomic-long.h b/sys/compat/linuxkpi/common/include/asm/atomic-long.h index b0763f456b90..b6909e1342e5 100644 --- a/sys/compat/linuxkpi/common/include/asm/atomic-long.h +++ b/sys/compat/linuxkpi/common/include/asm/atomic-long.h @@ -81,6 +81,21 @@ atomic_long_xchg(atomic_long_t *v, long val) return atomic_swap_long(&v->counter, val); } +static inline long +atomic_long_cmpxchg(atomic_long_t *v, long old, long new) +{ + long ret = old; + + for (;;) { + if (atomic_cmpset_long(&v->counter, old, new)) + break; + ret = READ_ONCE(v->counter); + if (ret != old) + break; + } + return (ret); +} + static inline int atomic_long_add_unless(atomic_long_t *v, long a, long u) { |