From: Thaddeus Woskowiak <tswoskowiak@gmail.com>
To: 9fans <9fans@9fans.net>
Subject: Re: [9fans] syscall silently kill processes
Date: Fri, 17 Jun 2022 09:46:49 -0400 [thread overview]
Message-ID: <CAG3JMtb6LuPc8G82iMg6SLDJ_U7-CYb1-x0_NR3C-zmGQbLudw@mail.gmail.com> (raw)
In-Reply-To: <79286caa2ca77ea9b9a1cd64918bdc5f28c8f180.camel@gmail.com>
I believe threadnotify() should be called from threadmain() to
properly register the handler in the rendez group.
On Fri, Jun 17, 2022 at 5:39 AM <andrey100100100@gmail.com> wrote:
>
> Hi all!
>
> Strange behavior of syscall 'read' with signal 'alarm' in followed
> simple program (ip/port - not matter):
>
> -----------------------------------------------------------------------
> #include <u.h>
> #include <libc.h>
> #include <thread.h>
>
> static int
> handler_alarm(void *, char *msg)
> {
> if(strstr(msg, "alarm"))
> return 1;
>
> return 0;
> }
>
> static void
> proc_udp(void *)
> {
> char resp[512];
> char req[] = "request";
> int fd;
>
> threadnotify(handler_alarm, 1);
>
> if((fd = dial("udp!185.157.221.201!5678", nil, nil, nil)) >=
> 0){
> if(write(fd, req, strlen(req)) == strlen(req)){
> fprint(1, "start\n");
> alarm(2000);
> read(fd, resp, sizeof(resp));
> alarm(0);
> fprint(1, "end\n");
> }
> close(fd);
> }
>
> threadexits(nil);
> }
>
> int mainstacksize = 5242880;
>
> void
> threadmain(int argc, char *argv[])
> {
> for(int i = 0; i < 80; i++){
> proccreate(proc_udp, nil, 10240);
> }
>
> sleep(5000);
> threadexitsall(nil);
> }
> -----------------------------------------------------------------------
>
> cpu% 6.out | grep end | wc -l
> 33
>
> sometimes little more or less
> but
>
> cpu% 6.out | grep start | wc -l
> 80
>
> always.
>
> Testing on Miller's RPi and 9front (amd64 & RPi 2)
>
> Why does read() kill process?
> Why not always?
> Why number of 'ended' processes arond 33?
> This is normal behavior?
> How to fix the program so that the processes do not lost?
>
> Can someone point me in the right direction?
>
> Thanks!
> Andrey
------------------------------------------
9fans: 9fans
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next prev parent reply other threads:[~2022-06-17 13:46 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-17 9:37 andrey100100100
2022-06-17 13:46 ` Thaddeus Woskowiak [this message]
2022-06-17 14:11 ` Jacob Moody
2022-06-17 14:39 ` Thaddeus Woskowiak
2022-06-17 15:06 ` andrey100100100
2022-06-17 16:08 ` Skip Tavakkolian
2022-06-17 16:11 ` Skip Tavakkolian
2022-06-17 16:16 ` Skip Tavakkolian
2022-06-17 17:42 ` adr
2022-06-17 16:11 ` Jacob Moody
2022-06-17 18:48 ` andrey100100100
2022-06-17 19:28 ` Jacob Moody
2022-06-17 21:15 ` adr
2022-06-18 6:40 ` andrey100100100
2022-06-18 8:37 ` adr
2022-06-18 9:22 ` adr
2022-06-18 12:53 ` Jacob Moody
2022-06-18 22:03 ` andrey100100100
2022-06-19 5:54 ` adr
2022-06-19 6:13 ` Jacob Moody
2022-06-18 22:22 ` andrey100100100
2022-06-18 16:57 ` andrey100100100
2022-06-19 2:40 ` adr
2022-06-19 5:01 ` adr
2022-06-19 8:52 ` andrey100100100
2022-06-19 10:32 ` adr
2022-06-19 11:40 ` andrey100100100
2022-06-19 12:01 ` andrey100100100
2022-06-19 15:10 ` andrey100100100
2022-06-19 16:41 ` adr
2022-06-19 21:22 ` andrey100100100
2022-06-19 21:26 ` andrey100100100
2022-06-20 4:41 ` adr
2022-06-20 5:39 ` andrey100100100
2022-06-20 5:59 ` adr
2022-06-20 15:56 ` andrey100100100
2022-06-20 22:29 ` Skip Tavakkolian
2022-06-21 7:07 ` andrey100100100
2022-06-21 11:26 ` adr
2022-06-21 13:03 ` andrey100100100
2022-06-21 13:22 ` adr
2022-06-28 15:28 ` adr
2022-06-28 16:43 ` ori
2022-06-28 18:19 ` adr
2022-06-28 18:28 ` adr
2022-06-28 19:09 ` andrey100100100
2022-06-28 19:42 ` adr
2022-06-29 13:14 ` adr
2022-06-21 13:47 ` andrey100100100
2022-06-21 7:22 ` adr
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