diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2018-08-05 16:39:29 +0200 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2018-08-05 16:39:29 +0200 |
commit | f2701b77bbd992f3df4631de8493f21db0830452 (patch) | |
tree | b05b2bf8b47002ae81c79aaa9de2a311b8ee075e /lib/dec_and_lock.c | |
parent | x86/KVM/VMX: Don't set l1tf_flush_l1d from vmx_handle_external_intr() (diff) | |
parent | Linux 4.18-rc7 (diff) | |
download | linux-f2701b77bbd992f3df4631de8493f21db0830452.tar.xz linux-f2701b77bbd992f3df4631de8493f21db0830452.zip |
Merge 4.18-rc7 into master to pick up the KVM dependcy
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'lib/dec_and_lock.c')
-rw-r--r-- | lib/dec_and_lock.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/lib/dec_and_lock.c b/lib/dec_and_lock.c index 347fa7ac2e8a..9555b68bb774 100644 --- a/lib/dec_and_lock.c +++ b/lib/dec_and_lock.c @@ -33,3 +33,19 @@ int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock) } EXPORT_SYMBOL(_atomic_dec_and_lock); + +int _atomic_dec_and_lock_irqsave(atomic_t *atomic, spinlock_t *lock, + unsigned long *flags) +{ + /* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */ + if (atomic_add_unless(atomic, -1, 1)) + return 0; + + /* Otherwise do it the slow way */ + spin_lock_irqsave(lock, *flags); + if (atomic_dec_and_test(atomic)) + return 1; + spin_unlock_irqrestore(lock, *flags); + return 0; +} +EXPORT_SYMBOL(_atomic_dec_and_lock_irqsave); |