From: andrey100100100@gmail.com
To: 9fans@9fans.net
Subject: Re: [9fans] syscall silently kill processes
Date: Mon, 20 Jun 2022 18:56:04 +0300 [thread overview]
Message-ID: <a6a977b8338888d71a1f29a5fa2c8e4b88040398.camel@gmail.com> (raw)
In-Reply-To: <2b857fe-c6df-a6b8-40ec-566c85b7377d@SDF.ORG>
В Пн, 20/06/2022 в 05:59 +0000, adr пишет:
> On Mon, 20 Jun 2022, adr wrote:
> > But I have something in mind for a case like
> > this, when all the processes are going to use the same handler
> > (that's why I was asking). Let me play with it a litle before I
> > share it.
>
> Ok, the idea is this: If in is bigger than zero in
> threadnotify(int (*f)(void*, char*), int in), the handler is register
> for the calling process. If in is 0, then the handler is cleared
> for the calling process. If in is -1, the handler is register for
> all processes and if in is less than -1, it is cleared for all
> processes (expect for those who have already registered it for
> themselves).
>
> Now back to your example, as all the processes are going to use the
> same handler,
> you just have to register it once in threadmain:
>
> #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;
> 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[])
> {
> threadnotify(handler_alarm, -1);
> for(int i = 0; i < 80; i++)
> proccreate(proc_udp, nil, 10240);
> sleep(5000);
> threadexitsall(nil);
> }
> Now,
> ; ./5.out | grep end | wc -l
> 80
>
> Are you happy Andrej?
Yes. Thank you very much! It's working!
How convenient it is to use - more experiments are needed.
>
> adr.
>
> /sys/src/libthread/sched.c:
> [...]
> if(t == nil){
> _threaddebug(DBGSCHED, "all threads gone;
> exiting");
> cancelnotes(p->pid);
> _schedexit(p);
> }
> [...]
> /sys/src/libthread/note.c
> [...]
> int
> threadnotify(int (*f)(void*, char*), int in)
> {
> int i, frompid, topid;
> int (*from)(void*, char*), (*to)(void*, char*);
>
> if(in && in>-2){
> from = nil;
> frompid = 0;
> to = f;
> topid = (in == -1)? -1 : _threadgetproc()->pid;
> lock(&onnotelock);
> for(i=0; i<NFN; i++)
> if(onnote[i]==to && onnotepid[i]==topid){
> unlock(&onnotelock);
> return i<NFN;
> }
> unlock(&onnotelock);
> }else{
> from = f;
> frompid = (in < -1)? -1 : _threadgetproc()->pid;
> to = nil;
> topid = 0;
> }
> lock(&onnotelock);
> for(i=0; i<NFN; i++)
> if(onnote[i]==from && onnotepid[i]==frompid){
> onnote[i] = to;
> onnotepid[i] = topid;
> break;
> }
> unlock(&onnotelock);
> return i<NFN;
> }
>
> void
> cancelnotes(int pid)
> {
> int i;
>
> lock(&onnotelock);
> for(i=0; i<NFN; i++)
> if(onnotepid[i] == pid){
> onnote[i] = nil;
> onnotepid[i] = 0;
> }
> unlock(&onnotelock);
> return;
> }
>
> static void
> delayednotes(Proc *p, void *v)
> {
> int i;
> Note *n;
> int (*fn)(void*, char*);
>
> if(!p->pending)
> return;
>
> p->pending = 0;
> for(n=notes; n<enotes; n++){
> if(n->proc == p){
> for(i=0; i<NFN; i++){
> if((onnotepid[i]!=p->pid &&
> onnotepid[i]!=-1) || (fn = onnote[i])==nil)
> continue;
> if((*fn)(v, n->s))
> break;
> [...]
> /sys/include/thread.h
> [...]
> void cancelnotes(int pid);
> [...]
>
Regards,
Andrej
------------------------------------------
9fans: 9fans
Permalink: https://9fans.topicbox.com/groups/9fans/Tfa6823048ad90a21-M3802ed594c69b660a4210973
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next prev parent reply other threads:[~2022-06-20 15:56 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
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 [this message]
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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