Hi,

 

That documentation is outdated and will be updated in the 3.1 release.

 

Zephyr supports new and delete operators.

 

Regards,

 

Stephanos

 

From: users@... <users@...> On Behalf Of giatorta via lists.zephyrproject.org
Sent: Monday, May 16, 2022 8:18 PM
To: users@...
Subject: [Zephyr-users] Zephyr C++ support #CPP

 

Hi all,

I read here:
https://docs.zephyrproject.org/3.0.0/reference/kernel/other/cxx_support.html

that Zephyr supports C++ applications, but that the kernel does not support the new and delete operators, which looks quite restrictive to me (since the standard library itself uses those features)

Here however:
https://github.com/zephyrproject-rtos/zephyr/issues/31281
I read that STL is among the C++ "things that work" in Zephyr

I am missing something? My interest is in writing C++ applications over Zephyr, not drivers/kernel modules

thanks in advance!
Gianluca

--

Dave Nadler, USA East Coast voice (978) 263-0097, drn@..., Skype 
 Dave.Nadler1

Hi all,

I read here:
https://docs.zephyrproject.org/3.0.0/reference/kernel/other/cxx_support.html

that Zephyr supports C++ applications, but that the kernel does not support the new and delete operators, which looks quite restrictive to me (since the standard library itself uses those features)

Here however:
https://github.com/zephyrproject-rtos/zephyr/issues/31281
I read that STL is among the C++ "things that work" in Zephyr

I am missing something? My interest is in writing C++ applications over Zephyr, not drivers/kernel modules

thanks in advance!
Gianluca

Gordon,

This seems to be something that would need to be included in the device driver rather than the PPP modem. I see the issue being how a generic driver could provide device specific control?

You could use the AT+UPSV command but not all modems will support it.

Billy..

The results from previous code were OK, I think it's a bug in the debugger. I posted the details here [^].
BR.

Hi,
I originally posted this question to stackoverflow [^] so I think its better not to duplicate the whole story here.
Supposing I have a DTS file with a content like this one below:

n: detectors {
    compatible = "foo-detectors";
        
    // Definition of first channel
    det0: det_0 {
        irq-pins = <13 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;
        label = "Bar detector channel 1";
    };
    // Definition of second channel
    det1: det_1 {
        irq-pins = <17 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;
        label = "Bar detector channel 2";
    };
};

And a structure like here below:

struct foo_detector_desc { 
    int irqpin; 
    int irqpin_flags;
}

How can I use macro DT_FOREACH_CHILD for populating an array with one item for each child of node detectors?

I tried this code below but, yet it compiled, the results where not what I wanted.

#define PIN_INFO_AND_COMMA(node_id) \
    { \
        .pin=DT_PROP_BY_IDX(node_id, irq_pins, 0),\
        .flags=DT_PROP_BY_IDX(node_id, irq_pins, 1),\
    },

const struct detector_data _det_data[] = {
    DT_FOREACH_CHILD(DT_NODELABEL(n), PIN_INFO_AND_COMMA)
};

BR.

Not public ones, no.  You can check kernel/include/ksched.h for the internal API for this.  I guess the immediate question has to be "what are you trying to do"?  Recognize that any decision made on the basis of this kind of stuff is going to be inherently racy without access to the scheduler's own synchronization (though on a single CPU device, just holding an interrupt lock is enough to be safe).

Also, just to clarify: k_sched_lock() doesn't mutate "scheduler" state at all, it's implemented via a trick that essentially elevates the current thread priority to a cooperative level, preventing preemption.

Andy

Are there any API calls for retrieving thread and scheduler status?  I'm looking for something that would indicate the following:

• Is the scheduler locked?
• What is the thread status? (Ready, Waiting, Suspended)

Thanks!

Hi Zephyr users!

I would like to profile my application and was wondering if there are tools available such as the famous ``perf``?

I have found ``THREAD_ANALYZER`` that is very useful but I would need more information about which functions is called and how long.

Happy hacking!

Guy

Hi Yshragai,

Small correction on my previous statement. As stated in the documentation, broadcasting is not possible:

Each message may be received by only one thread (i.e.
point-to- multipoint and broadcast messaging is not supported).

We had a small internal discussion about a similar topic this morning and for this reason, we decided to implement our own observer pattern by sending events to a dispatcher using message queue.

Anyway, if you have a better approach, I'm eager to hear more!

Best regards,

Guy


On 5/4/22 09:31, Guy Morand via lists.zephyrproject.org wrote:

Hi Yshragai,
Have you looked at 'k_mbox' data structure? It seems you can set a destination thread or broadcast messages with 'K_ANY':
https://docs.zephyrproject.org/latest/kernel/services/data_passing/mailboxes.html Hope this helps,
regards,
Guy
On 5/3/22 23:20, yshragai.firmware@... wrote:

Hi,
I'm wanting to design a firmware, for a small low-power embedded system, with an architecture that features a "bus" over which the firmware modules communicate. I'm wondering how to design this "bus".
Basically what I'm envisioning is modules sending messages over this bus that contain an address or module ID of some sort or another; the module that matches this address or ID would pick up the message off the bus.
One brute-force way to design this is a queue (such as a FIFO) per target module. This is not the most elegant or scalable solution, but it'll work... Is there a way to design this that's more scalable, and maybe even elegant?
I wish there were a mechanism in Zephyr by which a thread could subscribe to messages in a given queue not by sender ID (as is possible with a mailbox) but by some identifying characteristic of the message (e.g., by the value in the "info" field).
Thanks!

--
bytes at work
Technoparkstrasse 7
CH-8406 Winterthur
Switzerland

phone: +41 52 213 79 79

Hi Yshragai,

Have you looked at 'k_mbox' data structure? It seems you can set a destination thread or broadcast messages with 'K_ANY':
https://docs.zephyrproject.org/latest/kernel/services/data_passing/mailboxes.html

Hope this helps,
regards,

Guy

--
bytes at work
Technoparkstrasse 7
CH-8406 Winterthur
Switzerland

phone: +41 52 213 79 79