OpenForum RSS: clone() � malloc()

clone() � malloc() (pavlinux)

Sun, 15 Jan 2012 10:50:54 GMT

>>>[�� ]

�� ..��
[code]
static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;

int func(void *ptr) {

char *msg = (char *) ptr;

while (1) {
pthread_mutex_lock(&lock);
msg = malloc( 6);
strncpy(msg, "12345\0", 6);
free(msg);
pthread_mutex_unlock(&lock);
}
return 0;
}
[/code]

��, �� getrlimit(RLIMIT_STACK, rlim) ...

clone() � malloc() (nikolayshm)

Sun, 15 Jan 2012 00:08:31 GMT

>> �� , �� deadlock � ��
>> malloc()/free()
> �� . �� .

�� -�� - �� . malloc/free �� thread-safe :)

> �� -�� SIGSEGV - �� . ��, ��
> ��!!

��, �� .
SIGSEGV is the signal sent to a process when it makes an invalid memory reference, or segmentation fault.

clone() � malloc() (nikolayshm)

Sun, 15 Jan 2012 00:02:45 GMT

>>[�� ]
>> � �� ,
>> � �� .
> �� .
> �� , � ��

� �� , �� "��".

��, �� , �� . �� , �� .

�� , �� "�� , � �� " - ��, �� 2 �� , �� "��" ��?
�� :

��:

[code]
void **stack;
for (i = 0; i < 10; i++) {
stack = (void **)malloc(STACK_SIZE);
clone(func, stack, FLAGS, NULL);
}
[/code]

��:

[code]
void **stack;
stack = malloc(STACK_SIZE);
for (i = 0; i < 10; i++) {
*stack = (void *)(STACK_SIZE + (char *)stack);
clone(func, stack, FLAGS, NULL);
}
[/code]

clone() � malloc() (svn)

Sat, 14 Jan 2012 23:19:01 GMT

> �� , �� deadlock � ��
> malloc()/free()

�� . �� .

�� -�� SIGSEGV - �� . ��, �� !!
�� .

clone() � malloc() (pavlinux)

Sat, 14 Jan 2012 20:59:35 GMT

>[�� ]
> � �� ,
> � �� .

�� .
�� , � ��

[code]
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sched.h>
#include <signal.h>

#define STACK_SIZE (1024*1024)
#define FLAGS (CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_SYSVSEM|SIGCHLD)

int func(void *p) {

while (1) {
p = (char *)malloc(6);
memcpy(p, "12345\0", 6);
free(p);
}
}

int main() {

int i;
void **stack;

for (i = 0; i < 10; i++) {
stack = (void **)malloc(STACK_SIZE);
clone(func, stack, FLAGS, NULL);
}

sleep(10);
return 0;
}
[/code]

clone() � malloc() (nikolayshm)

Sat, 14 Jan 2012 16:04:17 GMT

> ��, �� ? � �� glibc, ��... �� ... :)

�� , �� .

> � �� *stack ��
> ��,
> �� 10 �� malloc � free!!!

�� :
for (i=0; i<10; i++) {
void *stack = malloc(STACK_SIZE);
}

�� stack �� , �� *stack �� .

> �� , �� (�� )

�� :

stack = malloc(STACK_SIZE);
for (i = 0; i < 10; i++) {
*stack = (void *)(STACK_SIZE + (char *)stack);
clone(func, stack, FLAGS, NULL);

�� STACK_SIZE,
��
�� clone �� .

� �� :
The child_stack argument specifies the location of the stack used by the child process. ... The calling pr

clone() � malloc() (pavlinux)

Sat, 14 Jan 2012 14:49:19 GMT

��, �� ? � �� glibc, ��... �� ... :)

� �� *stack �� ,
�� 10 �� malloc � free!!!
��, �� , �� SIGSEGV,
� �� .

�� , �� (�� )

clone() � malloc() (nikolayshm)

Wed, 11 Jan 2012 20:29:51 GMT

> �� -��, �� clone() "��
> �� (seg fault) �� ." - ��
> �� sigsegv �� "��" ��. SIGSEGV, ��,
> �� .

�� . SIGSEGV �� .
� �� (� �� ) SIGSEGV �� , �� exit() � �� . �� waitpid � �� .
� �� (pthread_create �� CLONE_THREAD) SIGSEGV �� , �� . �� .

clone() � malloc() (me)

Wed, 11 Jan 2012 19:11:42 GMT

>[�� ]
>>> ��. �� pthread_create �� CLONE_VM � �� .
>> �� -� �� -pthread ��? :)
>>> �� malloc �� , �� thread-safe,
>> �� pthread? �� pthread_create? ��? :)
> � �� -pthread � � ��. �� -D_REENTRANT - ��
> �� .
> ��... �� "��" �� pthread_create(), ��
> � �� . �� .
> �� pthread_create �� . � �� , ��
> �� (�� ).

��, � �� pthread_create �� clone. �� . (�� , ��. �� -�� , �� )

> �� .

�� -��, �� clone() "�� (seg fault) �� .