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Diffstat (limited to 'tools/perf/bench/futex.h')
| -rw-r--r-- | tools/perf/bench/futex.h | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/tools/perf/bench/futex.h b/tools/perf/bench/futex.h new file mode 100644 index 000000000000..7d0bda543e3d --- /dev/null +++ b/tools/perf/bench/futex.h @@ -0,0 +1,48 @@ +/* + * Glibc independent futex library for testing kernel functionality. + * Shamelessly stolen from Darren Hart <dvhltc@us.ibm.com> + * http://git.kernel.org/cgit/linux/kernel/git/dvhart/futextest.git/ + */ + +#ifndef _FUTEX_H +#define _FUTEX_H + +#include <unistd.h> +#include <sys/syscall.h> +#include <sys/types.h> +#include <linux/futex.h> + +/** + * futex() - SYS_futex syscall wrapper + * @uaddr: address of first futex + * @op: futex op code + * @val: typically expected value of uaddr, but varies by op + * @timeout: typically an absolute struct timespec (except where noted + * otherwise). Overloaded by some ops + * @uaddr2: address of second futex for some ops\ + * @val3: varies by op + * @opflags: flags to be bitwise OR'd with op, such as FUTEX_PRIVATE_FLAG + * + * futex() is used by all the following futex op wrappers. It can also be + * used for misuse and abuse testing. Generally, the specific op wrappers + * should be used instead. It is a macro instead of an static inline function as + * some of the types over overloaded (timeout is used for nr_requeue for + * example). + * + * These argument descriptions are the defaults for all + * like-named arguments in the following wrappers except where noted below. + */ +#define futex(uaddr, op, val, timeout, uaddr2, val3, opflags) \ + syscall(SYS_futex, uaddr, op | opflags, val, timeout, uaddr2, val3) + +/** + * futex_wait() - block on uaddr with optional timeout + * @timeout: relative timeout + */ +static inline int +futex_wait(u_int32_t *uaddr, u_int32_t val, struct timespec *timeout, int opflags) +{ + return futex(uaddr, FUTEX_WAIT, val, timeout, NULL, 0, opflags); +} + +#endif /* _FUTEX_H */ |