LWN: Comments on "2.6.27 - the rest of the story"

2.6.27 - the rest of the story

SEJeff — Mon, 18 Aug 2008 04:14:15 +0000

Sorry forgot to say you just escape it like a normal extended regexp:
+palm +"T\|X"

The above search in google finds exactly what you are looking for.

For better google-foo spend an afternoon glazing over this site:
http://johnny.ihackstuff.com/ghdb.php

2.6.27 - the rest of the story

SEJeff — Mon, 18 Aug 2008 04:11:52 +0000

Because google supports some extended regexp. Here is an example for you to google for:
+"happy tree friends" +"(date|candy)"

/proc/1234/syscall vs /proc/1234/wchan

jimparis — Sun, 03 Aug 2008 21:44:57 +0000

I don't get zero, but on my x86_32 machine I always get "_stext". My x86_64 machine gives more reasonable values. My guess would be this option:

config SCHED_NO_NO_OMIT_FRAME_POINTER
        def_bool y
        prompt "Single-depth WCHAN output"
        depends on X86_32
        help
          Calculate simpler /proc/<PID>/wchan values. If this option
          is disabled then wchan values will recurse back to the
          caller function. This provides more accurate wchan values,
          at the expense of slightly more scheduling overhead.

          If in doubt, say "Y".

On x86_32, by default, you will get no frame pointers, so the wchan output is not particularly useful. At least, that's how I read things. See arch/x86/Kconfig, kernel/Makefile, and arch/x86_kernel/process_32.c

By the way, this quadruple(?) negative in kernel/Makefile makes my head hurt:

ifneq ($(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER),y)

If it's not true that we're not not omitting them... AAH

2.6.27 - the rest of the story

BackSeat — Sat, 02 Aug 2008 20:00:23 +0000

The Palm T|X handheld computer is now supported.

Meaning Linux now runs on that platform? Pointer to more info, please.

Rant: why doesn't Google understand "T|X"?

/proc/1234/syscall vs /proc/1234/wchan

walles — Thu, 31 Jul 2008 08:23:46 +0000

I've asked this before both on the kernel mailing list and in Debian's bug tracker without getting any reply, but how is the syscall file different from the wchan file?

/proc/1234/wchan has been there for ages, but seems broken AFAICT (see the linked posts).

2.6.27 - the rest of the story

dlang — Thu, 31 Jul 2008 06:26:13 +0000

our editor is modest enough not to have mentioned the final line of the announcement

Quote:
Go to kernelnewbies or lwn for more reporting, I'm going to sleep for 
twenty-four hours now ;)

2.6.27 - the rest of the story

lacostej — Thu, 31 Jul 2008 01:41:18 +0000

Linux users hoping to upgrade their systems in the near future will be glad to know that a series of patches designed to make the kernel scale to 4096 processors has been merged.

Damn it, I will still have to use out of tree patches for my 8192 processors mythtv box.

Jonathan, thanks for the humor! Always appreciated.