From 8b92538d84e50062560ba33adbaed7887b6e4a42 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 14 Oct 2010 21:39:02 +0200 Subject: [PATCH] jump_label: Add atomic_t interface Add an interface to allow usage of jump_labels with atomic counters. Signed-off-by: Peter Zijlstra Acked-by: Frederic Weisbecker LKML-Reference: <20101014203625.501657727@chello.nl> Signed-off-by: Ingo Molnar --- include/linux/jump_label_ref.h | 44 ++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 include/linux/jump_label_ref.h diff --git a/include/linux/jump_label_ref.h b/include/linux/jump_label_ref.h new file mode 100644 index 000000000000..e5d012ad92c6 --- /dev/null +++ b/include/linux/jump_label_ref.h @@ -0,0 +1,44 @@ +#ifndef _LINUX_JUMP_LABEL_REF_H +#define _LINUX_JUMP_LABEL_REF_H + +#include +#include + +#ifdef HAVE_JUMP_LABEL + +static inline void jump_label_inc(atomic_t *key) +{ + if (atomic_add_return(1, key) == 1) + jump_label_enable(key); +} + +static inline void jump_label_dec(atomic_t *key) +{ + if (atomic_dec_and_test(key)) + jump_label_disable(key); +} + +#else /* !HAVE_JUMP_LABEL */ + +static inline void jump_label_inc(atomic_t *key) +{ + atomic_inc(key); +} + +static inline void jump_label_dec(atomic_t *key) +{ + atomic_dec(key); +} + +#undef JUMP_LABEL +#define JUMP_LABEL(key, label) \ +do { \ + if (unlikely(__builtin_choose_expr( \ + __builtin_types_compatible_p(typeof(key), atomic_t *), \ + atomic_read((atomic_t *)(key)), *(key)))) \ + goto label; \ +} while (0) + +#endif /* HAVE_JUMP_LABEL */ + +#endif /* _LINUX_JUMP_LABEL_REF_H */ -- 2.20.1