object pool, freertos queue and concurrent memory access

[braincat]

Coming from programming on intel cpus, I was wondering if it is safe to do the following:

Task 1

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1. SomeStruct *s = object_pool.allocate();
2. s->field = value;
3. xQueueSend(xQueue, &s, 0);

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1. Task 2:
2. SomeStruct *s = nullptr;
3. xQueueReceive(xQueue, &s, 0)
4. object_pool.release(s);
5. // and use data pointed to by "s" pointer

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allocate, release calls to object pool are protected by freertos semaphore.

If I were coding for x86-64, I would have to make sure that there is sufficient thread safety
in place, either using a queue with a mutex inside or synchronization using atomics, so that
there is a guarantee that the second task sees values in the memory pointed to by
the received pointer.

Is above safe to do on esp32? Thanks.

[ESP_Sprite]

The queue already guarantees software thread safety. Fyi, some of our drivers use more-or-less this paradigm to shuttle buffers around from/to the interrupt routines.