Socket manager

RE: Socket manager

newUser — Tue, 15 Sep 2020 15:01:36 GMT

Hi Carl,

Some quick experimentation proved that I should not always believe the Zephyr documentation:

k_thread_stack_t *testStacks[8];
static struct k_thread testThreads[8];

K_THREAD_STACK_DEFINE(networkingThreadStack, 2024);
struct k_thread networkingThread;



static void TestThreadFxn (const uint8_t *pId)
{
  printk("Created thread %u\n", *pId);
}

static void NetworkingThreadFxn (void)
{
  for (uint8_t i = 0; i < 8; i++)
  {
    testStacks[i] = k_malloc(1024);
    uint8_t *pId = k_malloc(sizeof(uint8_t));
    *pId = i;

    k_thread_create(&testThreads[i], testStacks[i],
                    1024,
                    (k_thread_entry_t) TestThreadFxn,
                    pId, NULL, NULL,
                    NETWORKING_THREAD_PRIORITY, 0, K_NO_WAIT);
  }
}

void NetworkingCreateThread (void)
{
  k_thread_create(&networkingThread, networkingThreadStack,
                  K_THREAD_STACK_SIZEOF(networkingThreadStack),
                  (k_thread_entry_t) NetworkingThreadFxn,
                  NULL, NULL, NULL,
                  NETWORKING_THREAD_PRIORITY, 0, K_NO_WAIT);
}

Created thread 0
Created thread 1
Created thread 2
Created thread 3
Created thread 4
Created thread 5
Created thread 6
Created thread 7

No crashes, as long as I allocate enough memory as stack.

RE: Socket manager

newUser — Tue, 15 Sep 2020 14:34:29 GMT

Hi Carl,

Thank you for your response, the extra information, and for taking the time to test it. I also saw the page you linked, but for k_object_alloc() it says "Currently, allocation of thread stacks is not supported."

Some more googling led me to CONFIG_DYNAMIC_OBJECTS, which I enabled and did not get an error on yet. I'll let you know if I have any luck.

RE: Socket manager

Carl Richard — Tue, 15 Sep 2020 14:30:01 GMT

Hi!

That makes sense and of course it's okay!

I did some more digging in the documentation and it seems that it may be possible after all. Take a look here. I'm not totally sure yet, though and will test it, but that will probably not be finished before noon tomorrow.

Best regards,
Carl Richard

RE: Socket manager

newUser — Tue, 15 Sep 2020 12:57:05 GMT

Hi again Carl!

I figured that yesterday was more about the higher level whereas this post was more directed to sockets specifically, hence the new post. I hope that's okay.

I was indeed curious whether thread stacks could be allocated dynamically, but if I understand correctly the answer is no. This means I should initialize 8 socket handler thread stacks beforehand (as the socket API supports 8 sockets I believe), even though I might not actually use all 8.

RE: Socket manager

Carl Richard — Tue, 15 Sep 2020 12:50:38 GMT

Hello!

As mentioned yesterday the event manager should be ideal for this kind of operation. Furthermore, I agree that dedicated threads for the sockets is a good idea. If you check out the Zephyr Documentation on threads it covers quite thoroughly how they are spawned, terminated and managed, so I recommend reading through that.

The available stack for threads must be allocated on beforehand, but threads can be spawned and terminated freely from what I know.

Best regards,
Carl Richard