Date: Mon, 12 Sep 2005 03:55:13 GMT From: Justin Shumaker <justin@arl.army.mil> To: freebsd-gnats-submit@FreeBSD.org Subject: threads/86004: libthr broken on amd64 Message-ID: <200509120355.j8C3tDgc028074@www.freebsd.org> Resent-Message-ID: <200509120400.j8C40dcF068556@freefall.freebsd.org>
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>Number: 86004
>Category: threads
>Synopsis: libthr broken on amd64
>Confidential: no
>Severity: serious
>Priority: high
>Responsible: freebsd-threads
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Mon Sep 12 04:00:38 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator: Justin Shumaker
>Release: 5.4 AMD64
>Organization:
U.S. Army Research Laboratory
>Environment:
FreeBSD xxx.army.mil 5.4-RELEASE-p6 FreeBSD 5.4-RELEASE-p6 #0: Wed Sep 7 17:41:09 EST 2005
>Description:
maping libpthread to libthr on AMD-64 causes multithreaded apps to core dump.
>How-To-Repeat:
Write a simple multithreaded test program in C. Here is a snippet of my test appplication. I have also tested with 3 other threaded apps all with the same results, so before complaining about a line of code in the below code, try cooking up your own. The application runs with libpthread.
#include <stdio.h>
#include <pthread.h>
#define WORK_SIZE 1024*128*8
int queue;
void* work(void *ptr) {
unsigned int i, q;
float a;
q = queue;
while(q--) {
a = 1;
for(i = 0; i < 128; i++)
a *= 1.001;
}
return 0;
}
int main(int argc, char *args[]) {
unsigned int i, tnum, n;
pthread_t t[8];
if(argc < 2) {
fprintf(stderr, "thread argument [1..8] required.\n");
exit(1);
}
tnum = atoi(args[1]);
if(tnum < 1 || tnum > 8) {
fprintf(stderr, "thread number must be from 1 to 8\n");
exit(1);
}
for(n = 0; n < 4; n++) {
queue = WORK_SIZE / tnum;
/* Launch the threads */
for(i = 0; i < tnum; i++)
pthread_create(&t[i], 0, work, 0);
/* Join the threads and finish */
for(i = 0; i < tnum; i++) {
pthread_join(t[i], 0);
printf("done: %d\n", i);
}
}
exit(0);
}
>Fix:
No idea, will require combing the libthr source and finding 64-bit unfriendly code or something it's tickling in the kernel.
>Release-Note:
>Audit-Trail:
>Unformatted:
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