diff options
author | Thomas Bertschinger <tahbertschinger@gmail.com> | 2024-01-15 23:41:02 -0700 |
---|---|---|
committer | Kent Overstreet <kent.overstreet@linux.dev> | 2024-01-16 01:47:05 -0500 |
commit | f5baaf48e3e82b1caf9f5cd1207d4d6feba3a2e5 (patch) | |
tree | 59f7b0e4667df7a9d3d5a45725f2aaab3e79b4c5 /c_src/libbcachefs/two_state_shared_lock.h | |
parent | fb35dbfdc5a9446fbb856dae5542b23963e28b89 (diff) |
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 <tahbertschinger@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Diffstat (limited to 'c_src/libbcachefs/two_state_shared_lock.h')
-rw-r--r-- | c_src/libbcachefs/two_state_shared_lock.h | 59 |
1 files changed, 59 insertions, 0 deletions
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 <linux/atomic.h> +#include <linux/sched.h> +#include <linux/wait.h> + +#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 */ |