cs161-list April 2002

cs161-list@lists.fas.harvard.edu

10 participants
21 discussions

by David Xiao

Hey everyone, I'm trying to build gdb for sys161 on x86 linux but I get some errors in the bfd library. Did anyone have these errors, and if so how'd you fix them? If you have a successfully built version, could you send the binary to me? (I assume they're statically linked, right?) Thanks, Dave

22 years

Solution set

by dholland＠eecs.harvard.edu

The solution set for assignment 4 has been released. We apologize for the delay. :( -- - David A. Holland / dholland(a)eecs.harvard.edu

22 years

Printing unaligned strings

by dholland＠eecs.harvard.edu

It was brought to my attention recently that gdb connected to sys161 would refuse to print strings unless they were aligned to start on a word boundary. This is badly broken and shouldn't have been tolerated -- I wish someone had told me earlier. It ought to be working now. A new sys161 release (0.99) has been issued and is posted in the usual places. (The funny part is, I'm sure I remember fixing this problem already once. I guess it regressed.) -- - David A. Holland / dholland(a)eecs.harvard.edu

22 years

Do we have to handle these too? ;)

by Charles Duan

lhd1:fstest.tmp10-11: 16560 bytes written sfs: looking up "fstest.tmp10-11". sfs: close vnode 0x80077c00. lhd1:fstest.tmp6-11: 16560 bytes read sfs: open vnode 0x80076c00. sfs: open vnode 0x80077c00. sfs: open vnode 0x80075c00. lNFS3 RFS3_GETATTR failed for server core-misc4 : RPC: Timed out NFS3 RFS3_GETATTR failed for server core-misc4 : RPC: Timed out hd1:fstest.tmp4-12: Write error: error 5 sfs: close vnode 0x80076800. lhd1:fstest.tmp10-11: Read error: error 5 sfs: close vnode 0x80077c00. lhd1:fstest.tmp1-12: Write error: error 5 sfs: close vnode 0x80076000. lhd1:fstest.tmp0-12: Write error: error 5 sfs: close vnode 0x80079400. *** Thread 10: file 11: failed *** Thread 4: file 12: failed sleep: Dropping thread createstress sleep: Dropping thread <boot/menu> sleep: Dropping thread createstress sleep: Dropping thread createstress sleep: Dropping thread createstress sleep: Dropping thread createstress panic: Assertion failed: index < b->nbits, at ../../lib/bitmap.c:125 (bitmap_unmark) sys161: 24172569417 cycles (7296090277k, 0u, 16876479140i) sys161: 577981 irqs 0 exns 335025r/117342w disk 9r/33211w console 0r/0w/1m emufs 0r/0w net sys161: Elapsed real time: 2474.814567 seconds (9.76743 mhz) sys161: Elapsed virtual time: 966.902776680 seconds (25 mhz)

22 years

concurrent dirops test

by David Holland

There have apparently been some requests for some more heavily concurrent filesystem tests. So I wrote one. It randomly mkdirs, rmdirs, and renames dirs from 20 processes at a time. I haven't actually run this on OS/161 yet. It runs on Unix and does compile on OS/161, so it is *probably* ok. You may need to increase physical memory to 1M to run it, because of all the kernel stacks it needs to allocate. It may take a long time to run. Etc. I realize it's fairly late in the game, but in case anyone is interested, here it is. --- snip; begin dirconc.c --- #include <sys/types.h> #include <sys/wait.h> #include <sys/stat.h> #include <errno.h> #include <stdio.h> #include <unistd.h> #include <stdlib.h> #include <stdarg.h> #include <string.h> #define NTRIES 100 /* loop count */ #define NPROCS 5 /* actually totals 4x this +1 processes */ #define TESTDIR "dirconc" #define NNAMES 4 #define NAMESIZE 32 #ifndef HOST /* OS/161 doesn't support the Unix exit status macros */ #define WIFSIGNALED(status) ((void)(status), 0) #define WTERMSIG(status) ((void)(status), 0) #define WIFEXITED(status) ((void)(status), 1) #define WEXITSTATUS(status) (status) #endif //////////////////////////////////////////////////////////// static const char *const names[NNAMES] = { "aaaa", "bbbb", "cccc", "dddd", }; static void choose_name(char *buf, size_t len) { const char *a, *b, *c; a = names[random()%NNAMES]; if (random()%2==0) { snprintf(buf, len, "%s", a); return; } b = names[random()%NNAMES]; if (random()%2==0) { snprintf(buf, len, "%s/%s", a, b); return; } c = names[random()%NNAMES]; snprintf(buf, len, "%s/%s/%s", a, b, c); } //////////////////////////////////////////////////////////// /* * The purpose of this is to be atomic. In our world, straight * printf tends not to be. */ static void say(const char *fmt, ...) { char buf[512]; va_list ap; va_start(ap, fmt); vsnprintf(buf, sizeof(buf), fmt, ap); va_end(ap); write(STDOUT_FILENO, buf, strlen(buf)); } //////////////////////////////////////////////////////////// static void dorename(const char *name1, const char *name2) { if (rename(name1, name2) < 0) { switch (errno) { case ENOENT: case ENOTEMPTY: case EINVAL: break; default: say("pid %d: rename %s -> %s: %s\n", getpid(), name1, name2, strerror(errno)); break; } } } static void domkdir(const char *name) { if (mkdir(name, 0775)<0) { switch (errno) { case ENOENT: case EEXIST: break; default: say("pid %d: mkdir %s: %s\n", getpid(), name, strerror(errno)); break; } } } static void dormdir(const char *name) { if (rmdir(name)<0) { switch (errno) { case ENOENT: case ENOTEMPTY: break; default: say("pid %d: rmdir %s: %s\n", getpid(), name, strerror(errno)); break; } } } static void cleanup_rmdir(const char *name) { if (rmdir(name)<0) { switch (errno) { case ENOENT: break; default: say("cleanup: rmdir %s: %s\n", getpid(), name, strerror(errno)); break; } } } //////////////////////////////////////////////////////////// static void rename_proc(void) { char name1[NAMESIZE], name2[NAMESIZE]; int ct; for (ct=0; ct<NTRIES; ct++) { choose_name(name1, sizeof(name1)); choose_name(name2, sizeof(name2)); say("pid %2d: rename %s -> %s\n", (int)getpid(), name1, name2); dorename(name1, name2); } } static void mkdir_proc(void) { char name[NAMESIZE]; int ct; for (ct=0; ct<NTRIES; ct++) { choose_name(name, sizeof(name)); say("pid %2d: mkdir %s\n", (int)getpid(), name); domkdir(name); } } static void rmdir_proc(void) { char name[NAMESIZE]; int ct; for (ct=0; ct<NTRIES; ct++) { choose_name(name, sizeof(name)); say("pid %2d: rmdir %s\n", (int)getpid(), name); dormdir(name); } } //////////////////////////////////////////////////////////// static pid_t dofork(void (*func)(void)) { pid_t pid; pid = fork(); if (pid < 0) { say("fork: %s\n", strerror(errno)); return -1; } if (pid == 0) { /* child */ func(); exit(0); } return pid; } static void run(void) { pid_t pids[NPROCS*4], wp; int i, status; for (i=0; i<NPROCS; i++) { pids[i*4] = dofork(mkdir_proc); pids[i*4+1] = dofork(mkdir_proc); pids[i*4+2] = dofork(rename_proc); pids[i*4+3] = dofork(rmdir_proc); } for (i=0; i<NPROCS*4; i++) { if (pids[i]>=0) { wp = waitpid(pids[i], &status, 0); if (wp<0) { say("waitpid %d: %s\n", (int) pids[i], strerror(errno)); } else if (WIFSIGNALED(status)) { say("pid %d: signal %d\n", (int) pids[i], WTERMSIG(status)); } else if (WIFEXITED(status) && WEXITSTATUS(status)!=0) { say("pid %d: exit %d\n", (int) pids[i], WEXITSTATUS(status)); } } } } //////////////////////////////////////////////////////////// static void setup(const char *fs) { if (chdir(fs)<0) { say("chdir: %s: %s\n", fs, strerror(errno)); exit(1); } if (mkdir(TESTDIR, 0775)<0) { say("mkdir: %s: %s\n", TESTDIR, strerror(errno)); exit(1); } if (chdir(TESTDIR)<0) { say("chdir: %s: %s\n", TESTDIR, strerror(errno)); exit(1); } } static void recursive_cleanup(const char *sofar, int depth) { char buf[NAMESIZE*2]; int i; for (i=0; i<NNAMES; i++) { snprintf(buf, sizeof(buf), "%s/%s", sofar, names[i]); if (rmdir(buf)<0) { if (errno==ENOTEMPTY) { recursive_cleanup(buf, depth+1); cleanup_rmdir(buf); } else if (errno!=ENOENT) { say("cleanup: rmdir %s: %s\n", getpid(), buf, strerror(errno)); } } } } static void cleanup(void) { recursive_cleanup(".", 0); chdir(".."); cleanup_rmdir(TESTDIR); } //////////////////////////////////////////////////////////// int main(int argc, char *argv[]) { const char *fs; long seed = 0; say("Concurrent directory ops test\n"); if (argc==0 || argv==NULL) { say("Warning: argc is 0 - assuming you mean to run on lhd1: " "with seed 0\n"); fs = "lhd1:"; } else if (argc==2) { fs = argv[1]; } else if (argc==3) { fs = argv[1]; seed = atoi(argv[2]); } else { say("Usage: dirconc filesystem [random-seed]\n"); exit(1); } srandom(seed); setup(fs); say("Starting in %s/%s\n", fs, TESTDIR); run(); say("Cleaning up\n"); cleanup(); return 0; }

22 years

Assignment 5 Topics & Assignment 4 Note

by mike vernal

Greetings -- Hopefully everyone is finishing up assignment 4. A quick note on that -- there was some confusion on what type of crash consistency you need to enforce (e.g., FFS forces meta-data to write synchronously). You don't have to implement any -- i.e., you don't need to worry about the case where your system crashes. Our apologies on an confusion on this point. On to assignment 5 -- please send mail to your TFs by Sunday morning (9:00 am) letting them know what topics you are considering. Your TF will then aim to cover that in section. thanks, -mike

22 years

/testbin/badcall empty-string tests

by David Holland

A. Student wrote: > I was wondering why badcall expects EFAULT to be returned when the > empty string is passed to rmdir (and other similar calls). > Technically, the memory address is valid, so wouldn't ENOENT make > more sense? Because it's broken, and the test framework in badcall isn't powerful enough to allow fixing it with a simple patch but rather needs a complete rewrite. So everyone please ignore its complaints about error returns on empty-string tests. :-| -- - David A. Holland / dholland(a)eecs.harvard.edu

22 years

Change of Office Hours Tomorrow

by Nicholas C. Murphy

Due to scheduling conflicts, we're rearranging office hours for tomorrow. Office hours will be held at the following times: Georgi: 7-9 pm Nick: 9-11 pm If you were somehow counting on a TF being available from 11-midnight, let us know and we can work something out. Nick

22 years

VFS layer bug

by David Holland

Some sharp-eyed people noticed something missing from an error-return path in vfs_open. Patch follows, will be posted on the web site, etc.: Index: src/kern/fs/vfs/vfspath.c =================================================================== RCS file: /disk/disk0/cs161/CVSREPO/os161/src/kern/fs/vfs/vfspath.c,v retrieving revision 1.5 diff -u -r1.5 vfspath.c --- vfspath.c 2001/09/18 22:19:20 1.5 +++ vfspath.c 2002/04/16 23:40:49 @@ -74,6 +74,14 @@ result = VOP_TRUNCATE(vn, 0); } if (result) { + int result2 = VOP_DECOPEN(vn); + if (result2) { + /* Blah. What else can we do? */ + panic("vfs_open: Error %d from VOP_DECOPEN " + "trying to recover from\n" + "error %d handling O_TRUNC\n", + result2, result); + } VOP_DECREF(vn); return result; } -- - David A. Holland / dholland(a)eecs.harvard.edu

22 years

Test program fixes

by David Holland

Two errors in the tests have been detected. The following patch fixes them. (The patch will be posted on the web site, etc., etc.) Index: src/testbin/badcall/badcall.c =================================================================== RCS file: /disk/disk0/cs161/CVSREPO/os161/src/testbin/badcall/badcall.c,v retrieving revision 1.9 diff -u -r1.9 badcall.c --- badcall.c 2002/02/16 01:36:28 1.9 +++ badcall.c 2002/04/14 18:39:19 @@ -1554,7 +1554,7 @@ } switch (errno) { - case EFAULT: + case EBADF: warnx("passed: getdirentry on %s fd", desc); break; default: Index: src/testbin/f_test/f_test.c =================================================================== RCS file: /disk/disk0/cs161/CVSREPO/os161/src/testbin/f_test/f_test.c,v retrieving revision 1.3 diff -u -r1.3 f_test.c --- f_test.c 2001/08/02 19:37:32 1.3 +++ f_test.c 2002/04/14 18:42:32 @@ -62,7 +62,7 @@ return -1; default: break; } - return 0; + return pid; } -- - David A. Holland / dholland(a)eecs.harvard.edu

22 years

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

cs161-list April 2002