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-rw-r--r--tools/perf/bench/futex.h146
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diff --git a/tools/perf/bench/futex.h b/tools/perf/bench/futex.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * 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>
+
+struct bench_futex_parameters {
+ bool silent;
+ bool fshared;
+ bool mlockall;
+ bool multi; /* lock-pi */
+ bool pi; /* requeue-pi */
+ bool broadcast; /* requeue */
+ unsigned int runtime; /* seconds*/
+ unsigned int nthreads;
+ unsigned int nfutexes;
+ unsigned int nwakes;
+ unsigned int nrequeue;
+};
+
+/**
+ * futex_syscall() - 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_syscall() 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.
+ *
+ * These argument descriptions are the defaults for all
+ * like-named arguments in the following wrappers except where noted below.
+ */
+static inline int
+futex_syscall(volatile u_int32_t *uaddr, int op, u_int32_t val, struct timespec *timeout,
+ volatile u_int32_t *uaddr2, int val3, int opflags)
+{
+ return syscall(SYS_futex, uaddr, op | opflags, val, timeout, uaddr2, val3);
+}
+
+static inline int
+futex_syscall_nr_requeue(volatile u_int32_t *uaddr, int op, u_int32_t val, int nr_requeue,
+ volatile u_int32_t *uaddr2, int val3, int opflags)
+{
+ return syscall(SYS_futex, uaddr, op | opflags, val, nr_requeue, 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_syscall(uaddr, FUTEX_WAIT, val, timeout, NULL, 0, opflags);
+}
+
+/**
+ * futex_wake() - wake one or more tasks blocked on uaddr
+ * @nr_wake: wake up to this many tasks
+ */
+static inline int
+futex_wake(u_int32_t *uaddr, int nr_wake, int opflags)
+{
+ return futex_syscall(uaddr, FUTEX_WAKE, nr_wake, NULL, NULL, 0, opflags);
+}
+
+/**
+ * futex_lock_pi() - block on uaddr as a PI mutex
+ */
+static inline int
+futex_lock_pi(u_int32_t *uaddr, struct timespec *timeout, int opflags)
+{
+ return futex_syscall(uaddr, FUTEX_LOCK_PI, 0, timeout, NULL, 0, opflags);
+}
+
+/**
+ * futex_unlock_pi() - release uaddr as a PI mutex, waking the top waiter
+ */
+static inline int
+futex_unlock_pi(u_int32_t *uaddr, int opflags)
+{
+ return futex_syscall(uaddr, FUTEX_UNLOCK_PI, 0, NULL, NULL, 0, opflags);
+}
+
+/**
+* futex_cmp_requeue() - requeue tasks from uaddr to uaddr2
+* @nr_wake: wake up to this many tasks
+* @nr_requeue: requeue up to this many tasks
+*/
+static inline int
+futex_cmp_requeue(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2, int nr_wake,
+ int nr_requeue, int opflags)
+{
+ return futex_syscall_nr_requeue(uaddr, FUTEX_CMP_REQUEUE, nr_wake, nr_requeue, uaddr2,
+ val, opflags);
+}
+
+/**
+ * futex_wait_requeue_pi() - block on uaddr and prepare to requeue to uaddr2
+ * @uaddr: non-PI futex source
+ * @uaddr2: PI futex target
+ *
+ * This is the first half of the requeue_pi mechanism. It shall always be
+ * paired with futex_cmp_requeue_pi().
+ */
+static inline int
+futex_wait_requeue_pi(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2,
+ struct timespec *timeout, int opflags)
+{
+ return futex_syscall(uaddr, FUTEX_WAIT_REQUEUE_PI, val, timeout, uaddr2, 0,
+ opflags);
+}
+
+/**
+ * futex_cmp_requeue_pi() - requeue tasks from uaddr to uaddr2
+ * @uaddr: non-PI futex source
+ * @uaddr2: PI futex target
+ * @nr_requeue: requeue up to this many tasks
+ *
+ * This is the second half of the requeue_pi mechanism. It shall always be
+ * paired with futex_wait_requeue_pi(). The first waker is always awoken.
+ */
+static inline int
+futex_cmp_requeue_pi(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2,
+ int nr_requeue, int opflags)
+{
+ return futex_syscall_nr_requeue(uaddr, FUTEX_CMP_REQUEUE_PI, 1, nr_requeue, uaddr2,
+ val, opflags);
+}
+
+#endif /* _FUTEX_H */