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authorThomas Bertschinger <tahbertschinger@gmail.com>2024-01-15 23:41:02 -0700
committerKent Overstreet <kent.overstreet@linux.dev>2024-01-16 01:47:05 -0500
commitf5baaf48e3e82b1caf9f5cd1207d4d6feba3a2e5 (patch)
tree59f7b0e4667df7a9d3d5a45725f2aaab3e79b4c5 /c_src/include/linux/seqlock.h
parentfb35dbfdc5a9446fbb856dae5542b23963e28b89 (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/include/linux/seqlock.h')
-rw-r--r--c_src/include/linux/seqlock.h47
1 files changed, 47 insertions, 0 deletions
diff --git a/c_src/include/linux/seqlock.h b/c_src/include/linux/seqlock.h
new file mode 100644
index 00000000..435420fe
--- /dev/null
+++ b/c_src/include/linux/seqlock.h
@@ -0,0 +1,47 @@
+#ifndef __LINUX_SEQLOCK_H
+#define __LINUX_SEQLOCK_H
+
+#include <linux/compiler.h>
+
+typedef struct seqcount {
+ unsigned sequence;
+} seqcount_t;
+
+static inline void seqcount_init(seqcount_t *s)
+{
+ s->sequence = 0;
+}
+
+static inline unsigned read_seqcount_begin(const seqcount_t *s)
+{
+ unsigned ret;
+
+repeat:
+ ret = READ_ONCE(s->sequence);
+ if (unlikely(ret & 1)) {
+ cpu_relax();
+ goto repeat;
+ }
+ smp_rmb();
+ return ret;
+}
+
+static inline int read_seqcount_retry(const seqcount_t *s, unsigned start)
+{
+ smp_rmb();
+ return unlikely(s->sequence != start);
+}
+
+static inline void write_seqcount_begin(seqcount_t *s)
+{
+ s->sequence++;
+ smp_wmb();
+}
+
+static inline void write_seqcount_end(seqcount_t *s)
+{
+ smp_wmb();
+ s->sequence++;
+}
+
+#endif /* __LINUX_SEQLOCK_H */