From: Lars E. G <lar...@er...> - 2012-06-06 10:56:57
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Hello, This may be caused by a bad configuration, or it may have been corrected already. In that case I apologize. I am using UML-kernel; 3.0.26 Anyway, this program; #include <stdio.h> #include <unistd.h> int main(int argc, char* argv[]) { printf("_SC_NPROCESSORS_CONF = %d\n", sysconf(_SC_NPROCESSORS_CONF)); printf("_SC_NPROCESSORS_ONLN = %d\n", sysconf(_SC_NPROCESSORS_ONLN)); return 0; } prints; _SC_NPROCESSORS_CONF = 0 _SC_NPROCESSORS_ONLN = 1 I found this when using http://lttng.org/ust on UML. It "almost worked". In fact everything except "lttng start" seems to work. I patched LTTng to fix the problem. The problem took a few hours to find so I post this just in case. Best Regards, Lars Ekman |
From: richard -r. w. <ric...@gm...> - 2012-06-06 11:18:15
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On Wed, Jun 6, 2012 at 12:56 PM, Lars Ekman G <lar...@er...> wrote: > I am using UML-kernel; 3.0.26 > > Anyway, this program; > > #include <stdio.h> > #include <unistd.h> > int main(int argc, char* argv[]) > { > printf("_SC_NPROCESSORS_CONF = %d\n", sysconf(_SC_NPROCESSORS_CONF)); > printf("_SC_NPROCESSORS_ONLN = %d\n", sysconf(_SC_NPROCESSORS_ONLN)); > return 0; > } > > prints; > > _SC_NPROCESSORS_CONF = 0 > _SC_NPROCESSORS_ONLN = 1 > > I found this when using http://lttng.org/ust on UML. > It "almost worked". In fact everything except "lttng start" > seems to work. I patched LTTng to fix the problem. > > The problem took a few hours to find so I post this > just in case. Thanks a lot for reporting this! What glibc-version are you using? -- Thanks, //richard |
From: Lars E. G <lar...@er...> - 2012-06-06 11:29:35
|
Hello, examples/lttng > /lib/libc.so.6 GNU C Library stable release version 2.11.1 (20100118), by Roland McGrath et al. Copyright (C) 2009 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Configured for i686-suse-linux. Compiled by GNU CC version 4.3.4 [gcc-4_3-branch revision 152973]. Compiled on a Linux 2.6.32 system on 2010-10-25. Available extensions: crypt add-on version 2.1 by Michael Glad and others GNU Libidn by Simon Josefsson NoVersion patch for broken glibc 2.0 binaries Native POSIX Threads Library by Ulrich Drepper et al BIND-8.2.3-T5B On a SLED 11 SP1 host (company WS, hence the ancient version) An "strace" shows; > strace numcpu (...stuff removed) open("/sys/devices/system/cpu", O_RDONLY|O_NONBLOCK|O_LARGEFILE|O_DIRECTORY|O_CLOEXEC) = 3 fcntl64(3, F_GETFD) = 0x1 (flags FD_CLOEXEC) brk(0) = 0x804b000 brk(0x8074000) = 0x8074000 getdents64(3, /* 7 entries */, 32768) = 208 getdents64(3, /* 0 entries */, 32768) = 0 brk(0x806c000) = 0x806c000 close(3) = 0 fstat64(1, {st_mode=S_IFCHR|0660, st_rdev=makedev(4, 0), ...}) = 0 ioctl(1, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig icanon echo ...}) = 0 mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x4018f000 write(1, "_SC_NPROCESSORS_CONF = 0\n", 25_SC_NPROCESSORS_CONF = 0 ) = 25 open("/proc/stat", O_RDONLY|O_CLOEXEC) = 3 read(3, "cpu 6 0 6 1228 0 0 0 0 0 0\ncpu0"..., 8192) = 210 close(3) = 0 write(1, "_SC_NPROCESSORS_ONLN = 1\n", 25_SC_NPROCESSORS_ONLN = 1 ) = 25 exit_group(0) = ? Regards, L Ekman -----Original Message----- From: richard -rw- weinberger [mailto:ric...@gm...] Sent: den 6 juni 2012 13:18 To: Lars Ekman G Cc: use...@li... Subject: Re: [uml-user] sysconf(_SC_NPROCESSORS_CONF) returns incorrect on UML (0) On Wed, Jun 6, 2012 at 12:56 PM, Lars Ekman G <lar...@er...> wrote: > I am using UML-kernel; 3.0.26 > > Anyway, this program; > > #include <stdio.h> > #include <unistd.h> > int main(int argc, char* argv[]) > { > printf("_SC_NPROCESSORS_CONF = %d\n", > sysconf(_SC_NPROCESSORS_CONF)); > printf("_SC_NPROCESSORS_ONLN = %d\n", > sysconf(_SC_NPROCESSORS_ONLN)); > return 0; > } > > prints; > > _SC_NPROCESSORS_CONF = 0 > _SC_NPROCESSORS_ONLN = 1 > > I found this when using http://lttng.org/ust on UML. > It "almost worked". In fact everything except "lttng start" > seems to work. I patched LTTng to fix the problem. > > The problem took a few hours to find so I post this just in case. Thanks a lot for reporting this! What glibc-version are you using? -- Thanks, //richard |
From: richard -r. w. <ric...@gm...> - 2012-06-06 11:33:59
|
On Wed, Jun 6, 2012 at 1:29 PM, Lars Ekman G <lar...@er...> wrote: > Hello, > > examples/lttng > /lib/libc.so.6 > GNU C Library stable release version 2.11.1 (20100118), by Roland McGrath et al. > Copyright (C) 2009 Free Software Foundation, Inc. > This is free software; see the source for copying conditions. > There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A > PARTICULAR PURPOSE. > Configured for i686-suse-linux. > Compiled by GNU CC version 4.3.4 [gcc-4_3-branch revision 152973]. > Compiled on a Linux 2.6.32 system on 2010-10-25. > Available extensions: > crypt add-on version 2.1 by Michael Glad and others > GNU Libidn by Simon Josefsson > NoVersion patch for broken glibc 2.0 binaries > Native POSIX Threads Library by Ulrich Drepper et al > BIND-8.2.3-T5B > > On a SLED 11 SP1 host (company WS, hence the ancient version) > Okay, I have an idea what's going on. I'll send a patch ASAP. -- Thanks, //richard |
From: richard -r. w. <ric...@gm...> - 2012-06-06 13:17:32
Attachments:
cpu_reg.diff
|
On Wed, Jun 6, 2012 at 1:33 PM, richard -rw- weinberger <ric...@gm...> wrote: > Okay, I have an idea what's going on. > I'll send a patch ASAP. > Does the attached patch solve the problem? -- Thanks, //richard |
From: Lars E. G <lar...@er...> - 2012-06-06 14:15:44
|
Hello, Yes, it works fine; / # /hostfs/numcpu _SC_NPROCESSORS_CONF = 1 _SC_NPROCESSORS_ONLN = 1 Thanks, Lars Ekman -----Original Message----- From: richard -rw- weinberger [mailto:ric...@gm...] Sent: den 6 juni 2012 15:17 To: Lars Ekman G Cc: use...@li... Subject: Re: [uml-user] sysconf(_SC_NPROCESSORS_CONF) returns incorrect on UML (0) On Wed, Jun 6, 2012 at 1:33 PM, richard -rw- weinberger <ric...@gm...> wrote: > Okay, I have an idea what's going on. > I'll send a patch ASAP. > Does the attached patch solve the problem? -- Thanks, //richard |
From: richard -r. w. <ric...@gm...> - 2012-06-06 15:15:00
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On Wed, Jun 6, 2012 at 4:15 PM, Lars Ekman G <lar...@er...> wrote: > > Hello, > > Yes, it works fine; > Okay, I'll queue this patch for -stable. -- Thanks, //richard |