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#ifndef GRPC_CORE_LIB_SUPPORT_SPINLOCK_H
#define GRPC_CORE_LIB_SUPPORT_SPINLOCK_H

#include <grpc/support/atm.h>

/* Simple spinlock. No backoff strategy, gpr_spinlock_lock is almost always
   a concurrency code smell. */
typedef struct { gpr_atm atm; } gpr_spinlock;

#define GPR_SPINLOCK_INITIALIZER ((gpr_spinlock){0})
#define GPR_SPINLOCK_STATIC_INITIALIZER \
  { 0 }
#define gpr_spinlock_trylock(lock) (gpr_atm_acq_cas(&(lock)->atm, 0, 1))
#define gpr_spinlock_unlock(lock) (gpr_atm_rel_store(&(lock)->atm, 0))
#define gpr_spinlock_lock(lock) \
  do {                          \
  } while (!gpr_spinlock_trylock((lock)))

#endif /* GRPC_CORE_LIB_SUPPORT_SPINLOCK_H */