Commit 31633694 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Peter Zijlstra
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selftests/futex: Add futex_numa_mpol 



Test the basic functionality for the NUMA and MPOL flags:
- FUTEX2_NUMA should take the NUMA node which is after the uaddr
  and use it.
- Only update the node if FUTEX_NO_NODE was set by the user
- FUTEX2_MPOL should use the memory based on the policy. I attempted to
  set the node with mbind() and then use this with MPOL but this fails
  and futex falls back to the default node for the current CPU.

Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250416162921.513656-22-bigeasy@linutronix.de
parent cda95fae

tools/testing/selftests/futex/functional/.gitignore

+1 −0
Original line number Diff line number Diff line 
# SPDX-License-Identifier: GPL-2.0-only

futex_numa_mpol

futex_priv_hash

futex_requeue

futex_requeue_pi

tools/testing/selftests/futex/functional/Makefile

+2 −1
Original line number Diff line number Diff line 
# SPDX-License-Identifier: GPL-2.0

INCLUDES := -I../include -I../../ $(KHDR_INCLUDES)

CFLAGS := $(CFLAGS) -g -O2 -Wall -pthread $(INCLUDES) $(KHDR_INCLUDES)

LDLIBS := -lpthread -lrt

LDLIBS := -lpthread -lrt -lnuma



LOCAL_HDRS := \

	../include/futextest.h \
@@ -18,6 +18,7 @@ TEST_GEN_PROGS := \ 
	futex_wait \

	futex_requeue \

	futex_priv_hash \

	futex_numa_mpol \

	futex_waitv



TEST_PROGS := run.sh

tools/testing/selftests/futex/functional/futex_numa_mpol.c

0 → 100644
+232 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * Copyright (C) 2025 Sebastian Andrzej Siewior <bigeasy@linutronix.de>

 */



#define _GNU_SOURCE



#include <errno.h>

#include <pthread.h>

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <numa.h>

#include <numaif.h>



#include <linux/futex.h>

#include <sys/mman.h>



#include "logging.h"

#include "futextest.h"

#include "futex2test.h"



#define MAX_THREADS	64



static pthread_barrier_t barrier_main;

static pthread_t threads[MAX_THREADS];



struct thread_args {

	void *futex_ptr;

	unsigned int flags;

	int result;

};



static struct thread_args thread_args[MAX_THREADS];



#ifndef FUTEX_NO_NODE

#define FUTEX_NO_NODE (-1)

#endif



#ifndef FUTEX2_MPOL

#define FUTEX2_MPOL	0x08

#endif



static void *thread_lock_fn(void *arg)

{

	struct thread_args *args = arg;

	int ret;



	pthread_barrier_wait(&barrier_main);

	ret = futex2_wait(args->futex_ptr, 0, args->flags, NULL, 0);

	args->result = ret;

	return NULL;

}



static void create_max_threads(void *futex_ptr)

{

	int i, ret;



	for (i = 0; i < MAX_THREADS; i++) {

		thread_args[i].futex_ptr = futex_ptr;

		thread_args[i].flags = FUTEX2_SIZE_U32 | FUTEX_PRIVATE_FLAG | FUTEX2_NUMA;

		thread_args[i].result = 0;

		ret = pthread_create(&threads[i], NULL, thread_lock_fn, &thread_args[i]);

		if (ret) {

			error("pthread_create failed\n", errno);

			exit(1);

		}

	}

}



static void join_max_threads(void)

{

	int i, ret;



	for (i = 0; i < MAX_THREADS; i++) {

		ret = pthread_join(threads[i], NULL);

		if (ret) {

			error("pthread_join failed for thread %d\n", errno, i);

			exit(1);

		}

	}

}



static void __test_futex(void *futex_ptr, int must_fail, unsigned int futex_flags)

{

	int to_wake, ret, i, need_exit = 0;



	pthread_barrier_init(&barrier_main, NULL, MAX_THREADS + 1);

	create_max_threads(futex_ptr);

	pthread_barrier_wait(&barrier_main);

	to_wake = MAX_THREADS;



	do {

		ret = futex2_wake(futex_ptr, to_wake, futex_flags);

		if (must_fail) {

			if (ret < 0)

				break;

			fail("Should fail, but didn't\n");

			exit(1);

		}

		if (ret < 0) {

			error("Failed futex2_wake(%d)\n", errno, to_wake);

			exit(1);

		}

		if (!ret)

			usleep(50);

		to_wake -= ret;



	} while (to_wake);

	join_max_threads();



	for (i = 0; i < MAX_THREADS; i++) {

		if (must_fail && thread_args[i].result != -1) {

			fail("Thread %d should fail but succeeded (%d)\n", i, thread_args[i].result);

			need_exit = 1;

		}

		if (!must_fail && thread_args[i].result != 0) {

			fail("Thread %d failed (%d)\n", i, thread_args[i].result);

			need_exit = 1;

		}

	}

	if (need_exit)

		exit(1);

}



static void test_futex(void *futex_ptr, int must_fail)

{

	__test_futex(futex_ptr, must_fail, FUTEX2_SIZE_U32 | FUTEX_PRIVATE_FLAG | FUTEX2_NUMA);

}



static void test_futex_mpol(void *futex_ptr, int must_fail)

{

	__test_futex(futex_ptr, must_fail, FUTEX2_SIZE_U32 | FUTEX_PRIVATE_FLAG | FUTEX2_NUMA | FUTEX2_MPOL);

}



static void usage(char *prog)

{

	printf("Usage: %s\n", prog);

	printf("  -c    Use color\n");

	printf("  -h    Display this help message\n");

	printf("  -v L  Verbosity level: %d=QUIET %d=CRITICAL %d=INFO\n",

	       VQUIET, VCRITICAL, VINFO);

}



int main(int argc, char *argv[])

{

	struct futex32_numa *futex_numa;

	int mem_size, i;

	void *futex_ptr;

	char c;



	while ((c = getopt(argc, argv, "chv:")) != -1) {

		switch (c) {

		case 'c':

			log_color(1);

			break;

		case 'h':

			usage(basename(argv[0]));

			exit(0);

			break;

		case 'v':

			log_verbosity(atoi(optarg));

			break;

		default:

			usage(basename(argv[0]));

			exit(1);

		}

	}



	mem_size = sysconf(_SC_PAGE_SIZE);

	futex_ptr = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);

	if (futex_ptr == MAP_FAILED) {

		error("mmap() for %d bytes failed\n", errno, mem_size);

		return 1;

	}

	futex_numa = futex_ptr;



	info("Regular test\n");

	futex_numa->futex = 0;

	futex_numa->numa = FUTEX_NO_NODE;

	test_futex(futex_ptr, 0);



	if (futex_numa->numa == FUTEX_NO_NODE) {

		fail("NUMA node is left unitiliazed\n");

		return 1;

	}



	info("Memory too small\n");

	test_futex(futex_ptr + mem_size - 4, 1);



	info("Memory out of range\n");

	test_futex(futex_ptr + mem_size, 1);



	futex_numa->numa = FUTEX_NO_NODE;

	mprotect(futex_ptr, mem_size, PROT_READ);

	info("Memory, RO\n");

	test_futex(futex_ptr, 1);



	mprotect(futex_ptr, mem_size, PROT_NONE);

	info("Memory, no access\n");

	test_futex(futex_ptr, 1);



	mprotect(futex_ptr, mem_size, PROT_READ | PROT_WRITE);

	info("Memory back to RW\n");

	test_futex(futex_ptr, 0);



	/* MPOL test. Does not work as expected */

	for (i = 0; i < 4; i++) {

		unsigned long nodemask;

		int ret;



		nodemask = 1 << i;

		ret = mbind(futex_ptr, mem_size, MPOL_BIND, &nodemask,

			    sizeof(nodemask) * 8, 0);

		if (ret == 0) {

			info("Node %d test\n", i);

			futex_numa->futex = 0;

			futex_numa->numa = FUTEX_NO_NODE;



			ret = futex2_wake(futex_ptr, 0, FUTEX2_SIZE_U32 | FUTEX_PRIVATE_FLAG | FUTEX2_NUMA | FUTEX2_MPOL);

			if (ret < 0)

				error("Failed to wake 0 with MPOL.\n", errno);

			if (0)

				test_futex_mpol(futex_numa, 0);

			if (futex_numa->numa != i) {

				fail("Returned NUMA node is %d expected %d\n",

				     futex_numa->numa, i);

			}

		}

	}

	return 0;

}

tools/testing/selftests/futex/functional/run.sh

+3 −0
Original line number Diff line number Diff line
@@ -86,3 +86,6 @@ echo 
echo

./futex_priv_hash $COLOR

./futex_priv_hash -g $COLOR



echo

./futex_numa_mpol $COLOR

tools/testing/selftests/futex/include/futex2test.h

+52 −0
Original line number Diff line number Diff line
@@ -18,14 +18,43 @@ struct futex_waitv { 
};

#endif



#ifndef __NR_futex_wake

#define __NR_futex_wake 454

#endif



#ifndef __NR_futex_wait

#define __NR_futex_wait 455

#endif



#ifndef FUTEX2_SIZE_U32

#define FUTEX2_SIZE_U32 0x02

#endif



#ifndef FUTEX2_NUMA

#define FUTEX2_NUMA 0x04

#endif



#ifndef FUTEX2_MPOL

#define FUTEX2_MPOL 0x08

#endif



#ifndef FUTEX2_PRIVATE

#define FUTEX2_PRIVATE FUTEX_PRIVATE_FLAG

#endif



#ifndef FUTEX2_NO_NODE

#define FUTEX_NO_NODE (-1)

#endif



#ifndef FUTEX_32

#define FUTEX_32 FUTEX2_SIZE_U32

#endif



struct futex32_numa {

	futex_t futex;

	futex_t numa;

};



/**

 * futex_waitv - Wait at multiple futexes, wake on any

 * @waiters:    Array of waiters
@@ -38,3 +67,26 @@ static inline int futex_waitv(volatile struct futex_waitv *waiters, unsigned lon 
{

	return syscall(__NR_futex_waitv, waiters, nr_waiters, flags, timo, clockid);

}



/*

 * futex_wait() - block on uaddr with optional timeout

 * @val:	Expected value

 * @flags:	FUTEX2 flags

 * @timeout:	Relative timeout

 * @clockid:	Clock id for the timeout

 */

static inline int futex2_wait(void *uaddr, long val, unsigned int flags,

			      struct timespec *timeout, clockid_t clockid)

{

	return syscall(__NR_futex_wait, uaddr, val, ~0U, flags, timeout, clockid);

}



/*

 * futex2_wake() - Wake a number of futexes

 * @nr:		Number of threads to wake at most

 * @flags:	FUTEX2 flags

 */

static inline int futex2_wake(void *uaddr, int nr, unsigned int flags)

{

	return syscall(__NR_futex_wake, uaddr, ~0U, nr, flags);

}