[patch] spinlock consolidation, v2

[Ingo Molnar <mingo@elte.hu>]

the latest version of the spinlock consolidation patch can be found at:

  http://redhat.com/~mingo/spinlock-patches/consolidate-spinlocks.patch

the patch is now complete in the sense that it does everything i wanted 
it to do. If you have any other suggestions (or i have missed to 
incorporate an earlier suggestion of yours), please yell.

Changes:

 - all architectures have been converted to the new spinlock code.
   arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via
   crosscompilers. Alpha, m32r, mips, parisc, sh, sparc, sparc64 has
   not been tested yet, but should be mostly fine. x86 and x64 was
   boot-tested in all relevant .config variations. It all brought a nice 
   reduction in source code size:

     62 files changed, 1455 insertions(+), 3025 deletions(-)

   Al, would you be interested in checking this patch on your build 
   farm? It should build on all architectures, UP and SMP alike.

   (NOTE: i've switched sparc32, sparc64, alpha, ppc, parisc to use the 
    generic spinlock debugging code. I believe the generic debugging 
    code is now capable enough to be a replacement - but especially the 
    Sparc ones are pretty advanced; so if i've missed some important
    feature please let me know and i'll implement it in the generic 
    code.)

 - linux/spinlock_types.h: new, pure header file that can be used
   by other headers to define spinlock fields - without having to
   pull in all the other include files that are needed on the
   implementational side. (Roman Zippel)

 - lib/spinlock_debug.c: got rid of the __FILE__/__LINE__ debug output 
   (suggested by Ingo Oeser), and streamlined the debug output. 
   Implemented 'lockup detection' which is a must for architectures that 
   dont have the equivalent of an NMI watchdog. (but is useful on other 
   architectures as well.) Both spinlocks and rwlocks are now fully 
   debugged.

 - linux/spinlock.h: got rid of the ATOMIC_DEC_AND_LOCK cruft. This is 
   achieved by not doing the UP-nonpreempt-nondebug specific 
   optimization but letting it pick the generic _atomic_dec_and_lock 
   function. The assembly looks sane on x86 (no locked ops, etc.) so 
   there's no performance problem. Other architectures should work fine 
   too, those which implement _atomic_dec_and_lock unconditionally might 
   want to review whether they want to use the CONFIG_HAVE_DEC_LOCK 
   mechanism to get the optimized (generic) version of the function on 
   UP.

 - asm-generic/spinlock_types_up.h: further simplifications (suggested
   by Arjan van de Ven), typo fixed

 - linux/spinlock_up.h: since this an UP-nondebug branch now, the macros 
   were simplified and streamlined significantly.

 - asm-generic/spinlock_up.h: further cleanups, reordering of op
   definitions into 'natural' op order.

 - asm-i386/spinlock.h and asm-x86_64/spinlock.h: reordering of ops, 
   cleanups

 - include/linux/spinlock.h: more cleanups, reordering

 - linux/spinlock_smp.h: cleanups, reordering of prototypes

 - kernel/spinlock.c: fixed bug in generic_raw_read_trylock and renamed 
   it to generic__raw_read_trylock to ease conversion.

 - lib/kernel_lock.c: simplification

 - (lots of small details i forgot)

	Ingo
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/