Passing socket struct between kernel threads - module programming


 
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Old 02-12-2009
Error Passing socket struct between kernel threads - module programming

I write kernel module with kernel threads using
linux/kthread.h on 2.6.* kernel

I tried to passing data between two kernel threads
with data argument of kthread_run( fun, data , NAME );
but this is not work I dont know why. I tried many possibility
and nothing works.

So I thought that maybe something like this will work
but not.
Code:
typedef struct my {
    struct socket *tmp;
    struct task_struct *task;
    int (*fun)(void * );
} table[10];
/* this is global static table */

int kthread_fun1(void *d) {
    sock_create( ...., &(tab[0].tmp) )
    printk(" %p ", tab[0].tmp ) <- THIS IS NOT NULL OK
}

int ktrhead_fun2( void *d ) {
    tab[0].tmp <- THIS IS NULL IN THIS CASE WHY

}

init_function_of_module {
    kthread_run( ..., fun1, ... )
 
    kthread_run( ..., fun2, ... )
}

Iam sure that fun1 thread was executed before fun2, I used semaphores ( actually completion mechanism ).
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max_thread_proc(5)						File Formats Manual						max_thread_proc(5)

NAME
max_thread_proc - defines the maximum number of concurrent threads allowed per process. VALUES
Failsafe Default Allowed values Recommended values DESCRIPTION
is a dynamic tunable that limits the maximum number of threads allowed per process on the system. When tuning the maximum number of threads allowed per process will be the new value of No process will be able to create new threads such that the total count of its threads exceeds Who is Expected to Change This Tunable? System administrators that run applications on their systems requiring a high number of threads per process. Restrictions on Changing The effect of tuning on existing processes is undefined. However, existing threads will not be effected. When Should the Value of This Tunable Be Raised? The value of should be raised if there is a need to run an application that requires a higher number of threads per process than what is currently set to accommodate. Also, if thread creation fails with the value of then it could indicate that the has been reached. However, reaching is not the only reason why a thread creation could fail with may be returned if the system tunable has been reached or memory on the system is exhausted. What Are the Side Effects of Raising the Value? A group of processes may be able to exhaust the system wide limit of threads on the system. When Should the Value of This Tunable Be Lowered? If you feel that it is necessary to limit the number of threads allowed per process. What Are the Side Effects of Lowering the Value? Some applications which need a high number of threads may behave differently or fail to operate. What Other Tunable Values Should Be Changed at the Same Time? You may want to look at the value of WARNINGS
All HP-UX kernel tunable parameters are release specific. This parameter may be removed or have its meaning changed in future releases of HP-UX. Installation of optional kernel software, from HP or other vendors, may cause changes to tunable parameter values. After installation, some tunable parameters may no longer be at the default or recommended values. For information about the effects of installation on tun- able values, consult the documentation for the kernel software being installed. For information about optional kernel software that was factory installed on your system, see at AUTHOR
was developed by HP. SEE ALSO
nkthread(5). Tunable Kernel Parameters max_thread_proc(5)