Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 2cd36fb3 authored by Alexey Dobriyan's avatar Alexey Dobriyan Committed by Linus Torvalds
Browse files

proc: test /proc/thread-self symlink 

Same story: I have WIP patch to make it faster, so better have a test
as well.

Link: http://lkml.kernel.org/r/20180627195209.GC18113@avx2


Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 61d47c4e

tools/testing/selftests/proc/.gitignore

+1 −0
Original line number Diff line number Diff line
@@ -10,3 +10,4 @@ 
/proc-uptime-002

/read

/self

/thread-self

tools/testing/selftests/proc/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -14,5 +14,6 @@ TEST_GEN_PROGS += proc-uptime-001 
TEST_GEN_PROGS += proc-uptime-002

TEST_GEN_PROGS += read

TEST_GEN_PROGS += self

TEST_GEN_PROGS += thread-self



include ../lib.mk

tools/testing/selftests/proc/proc.h

+5 −0
Original line number Diff line number Diff line
@@ -14,6 +14,11 @@ static inline pid_t sys_getpid(void) 
	return syscall(SYS_getpid);

}



static inline pid_t sys_gettid(void)

{

	return syscall(SYS_gettid);

}



static inline bool streq(const char *s1, const char *s2)

{

	return strcmp(s1, s2) == 0;

tools/testing/selftests/proc/thread-self.c

0 → 100644
+64 −0
Original line number Diff line number Diff line 
/*

 * Copyright © 2018 Alexey Dobriyan <adobriyan@gmail.com>

 *

 * Permission to use, copy, modify, and distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 */

// Test that /proc/thread-self gives correct TGID/PID.

#undef NDEBUG

#include <assert.h>

#include <sched.h>

#include <stdio.h>

#include <unistd.h>

#include <sys/mman.h>

#include <sys/wait.h>



#include "proc.h"



int f(void *arg)

{

	char buf1[64], buf2[64];

	pid_t pid, tid;

	ssize_t rv;



	pid = sys_getpid();

	tid = sys_gettid();

	snprintf(buf1, sizeof(buf1), "%u/task/%u", pid, tid);



	rv = readlink("/proc/thread-self", buf2, sizeof(buf2));

	assert(rv == strlen(buf1));

	buf2[rv] = '\0';

	assert(streq(buf1, buf2));



	if (arg)

		exit(0);

	return 0;

}



int main(void)

{

	const int PAGE_SIZE = sysconf(_SC_PAGESIZE);

	pid_t pid;

	void *stack;



	/* main thread */

	f((void *)0);



	stack = mmap(NULL, 2 * PAGE_SIZE, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);

	assert(stack != MAP_FAILED);

	/* side thread */

	pid = clone(f, stack + PAGE_SIZE, CLONE_THREAD|CLONE_SIGHAND|CLONE_VM, (void *)1);

	assert(pid > 0);

	pause();



	return 0;

}