From f5baaf48e3e82b1caf9f5cd1207d4d6feba3a2e5 Mon Sep 17 00:00:00 2001 From: Thomas Bertschinger Date: Mon, 15 Jan 2024 23:41:02 -0700 Subject: move Rust sources to top level, C sources into c_src This moves the Rust sources out of rust_src/ and into the top level. Running the bcachefs executable out of the development tree is now: $ ./target/release/bcachefs command or $ cargo run --profile release -- command instead of "./bcachefs command". Building and installing is still: $ make && make install Signed-off-by: Thomas Bertschinger Signed-off-by: Kent Overstreet --- c_src/libbcachefs/two_state_shared_lock.h | 59 +++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 c_src/libbcachefs/two_state_shared_lock.h (limited to 'c_src/libbcachefs/two_state_shared_lock.h') diff --git a/c_src/libbcachefs/two_state_shared_lock.h b/c_src/libbcachefs/two_state_shared_lock.h new file mode 100644 index 00000000..90580177 --- /dev/null +++ b/c_src/libbcachefs/two_state_shared_lock.h @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _BCACHEFS_TWO_STATE_LOCK_H +#define _BCACHEFS_TWO_STATE_LOCK_H + +#include +#include +#include + +#include "util.h" + +/* + * Two-state lock - can be taken for add or block - both states are shared, + * like read side of rwsem, but conflict with other state: + */ +typedef struct { + atomic_long_t v; + wait_queue_head_t wait; +} two_state_lock_t; + +static inline void two_state_lock_init(two_state_lock_t *lock) +{ + atomic_long_set(&lock->v, 0); + init_waitqueue_head(&lock->wait); +} + +static inline void bch2_two_state_unlock(two_state_lock_t *lock, int s) +{ + long i = s ? 1 : -1; + + EBUG_ON(atomic_long_read(&lock->v) == 0); + + if (atomic_long_sub_return_release(i, &lock->v) == 0) + wake_up_all(&lock->wait); +} + +static inline bool bch2_two_state_trylock(two_state_lock_t *lock, int s) +{ + long i = s ? 1 : -1; + long v = atomic_long_read(&lock->v), old; + + do { + old = v; + + if (i > 0 ? v < 0 : v > 0) + return false; + } while ((v = atomic_long_cmpxchg_acquire(&lock->v, + old, old + i)) != old); + return true; +} + +void __bch2_two_state_lock(two_state_lock_t *, int); + +static inline void bch2_two_state_lock(two_state_lock_t *lock, int s) +{ + if (!bch2_two_state_trylock(lock, s)) + __bch2_two_state_lock(lock, s); +} + +#endif /* _BCACHEFS_TWO_STATE_LOCK_H */ -- cgit v1.2.3