Re: How to post a message to a kernel thread

Daniele Bellucci <bellucda@tiscali.it> · Mon, 15 Dec 2003 12:17:32 +0100

    Thanks for your mail. I basically want to send the packets
    received by the synchronous ppp tty module (ppp_synctty.c)
    to a socket application. Since the ppp transmit function is called
    from interrupt context, i am not able to invoke the sock_sendmsg
    call.

i don't know much about the ppp core, so i assume the above statement is 
correct

    So i thought of creating a new kernel thread which will have a queue

    so that from the sync ppp tty module i will post the packets to this

    queue. From this kernel thread i can write the message to the 
    socket.

well looks like all you need is a static data structure like: buffer / 
linked list. They both need

to be protected by a spinlock (due to the interrupt context issues).

My idea is:

the kernel_thread goes to sleep (in a wait queue) waiting for a packet.

When a packet is received from the ppp core you enqueue it in the 
choosen data structre (buffer/linked list), and wake the kernel_thread.

If you're working against the 2.6, take a look at the workqueue ... 
maybe you

can simplify your code by using on of such queue.

Hope these helps.

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