d2f3f5d2e9
Allows a way of measuring low level kernel implementation of FUTEX_LOCK_PI and FUTEX_UNLOCK_PI. The program comes in two flavors: (i) single futex (default), all threads contend on the same uaddr. For the sake of the benchmark, we call into kernel space even when the lock is uncontended. The kernel will set it to TID, any waters that come in and contend for the pi futex will be handled respectively by the kernel. (ii) -M option for multiple futexes, each thread deals with its own futex. This is a trivial scenario and only measures kernel handling of 0->TID transition. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Mel Gorman <mgorman@suse.de> Link: http://lkml.kernel.org/r/1436259353.12255.78.camel@stgolabs.net Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
105 lines
3.0 KiB
C
105 lines
3.0 KiB
C
/*
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* Glibc independent futex library for testing kernel functionality.
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* Shamelessly stolen from Darren Hart <dvhltc@us.ibm.com>
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* http://git.kernel.org/cgit/linux/kernel/git/dvhart/futextest.git/
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*/
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#ifndef _FUTEX_H
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#define _FUTEX_H
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#include <unistd.h>
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#include <sys/syscall.h>
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#include <sys/types.h>
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#include <linux/futex.h>
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/**
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* futex() - SYS_futex syscall wrapper
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* @uaddr: address of first futex
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* @op: futex op code
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* @val: typically expected value of uaddr, but varies by op
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* @timeout: typically an absolute struct timespec (except where noted
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* otherwise). Overloaded by some ops
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* @uaddr2: address of second futex for some ops\
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* @val3: varies by op
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* @opflags: flags to be bitwise OR'd with op, such as FUTEX_PRIVATE_FLAG
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*
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* futex() is used by all the following futex op wrappers. It can also be
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* used for misuse and abuse testing. Generally, the specific op wrappers
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* should be used instead. It is a macro instead of an static inline function as
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* some of the types over overloaded (timeout is used for nr_requeue for
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* example).
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*
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* These argument descriptions are the defaults for all
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* like-named arguments in the following wrappers except where noted below.
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*/
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#define futex(uaddr, op, val, timeout, uaddr2, val3, opflags) \
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syscall(SYS_futex, uaddr, op | opflags, val, timeout, uaddr2, val3)
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/**
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* futex_wait() - block on uaddr with optional timeout
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* @timeout: relative timeout
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*/
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static inline int
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futex_wait(u_int32_t *uaddr, u_int32_t val, struct timespec *timeout, int opflags)
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{
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return futex(uaddr, FUTEX_WAIT, val, timeout, NULL, 0, opflags);
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}
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/**
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* futex_wake() - wake one or more tasks blocked on uaddr
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* @nr_wake: wake up to this many tasks
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*/
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static inline int
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futex_wake(u_int32_t *uaddr, int nr_wake, int opflags)
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{
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return futex(uaddr, FUTEX_WAKE, nr_wake, NULL, NULL, 0, opflags);
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}
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/**
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* futex_lock_pi() - block on uaddr as a PI mutex
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* @detect: whether (1) or not (0) to perform deadlock detection
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*/
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static inline int
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futex_lock_pi(u_int32_t *uaddr, struct timespec *timeout, int detect,
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int opflags)
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{
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return futex(uaddr, FUTEX_LOCK_PI, detect, timeout, NULL, 0, opflags);
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}
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/**
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* futex_unlock_pi() - release uaddr as a PI mutex, waking the top waiter
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*/
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static inline int
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futex_unlock_pi(u_int32_t *uaddr, int opflags)
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{
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return futex(uaddr, FUTEX_UNLOCK_PI, 0, NULL, NULL, 0, opflags);
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}
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/**
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* futex_cmp_requeue() - requeue tasks from uaddr to uaddr2
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* @nr_wake: wake up to this many tasks
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* @nr_requeue: requeue up to this many tasks
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*/
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static inline int
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futex_cmp_requeue(u_int32_t *uaddr, u_int32_t val, u_int32_t *uaddr2, int nr_wake,
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int nr_requeue, int opflags)
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{
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return futex(uaddr, FUTEX_CMP_REQUEUE, nr_wake, nr_requeue, uaddr2,
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val, opflags);
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}
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#ifndef HAVE_PTHREAD_ATTR_SETAFFINITY_NP
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#include <pthread.h>
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static inline int pthread_attr_setaffinity_np(pthread_attr_t *attr,
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size_t cpusetsize,
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cpu_set_t *cpuset)
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{
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attr = attr;
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cpusetsize = cpusetsize;
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cpuset = cpuset;
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return 0;
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}
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#endif
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#endif /* _FUTEX_H */
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