1. 11 10月, 2007 1 次提交
  2. 07 12月, 2006 1 次提交
  3. 01 10月, 2006 1 次提交
    • M
      [PATCH] Directed yield: cpu_relax variants for spinlocks and rw-locks · ef6edc97
      Martin Schwidefsky 提交于
      On systems running with virtual cpus there is optimization potential in
      regard to spinlocks and rw-locks.  If the virtual cpu that has taken a lock
      is known to a cpu that wants to acquire the same lock it is beneficial to
      yield the timeslice of the virtual cpu in favour of the cpu that has the
      lock (directed yield).
      
      With CONFIG_PREEMPT="n" this can be implemented by the architecture without
      common code changes.  Powerpc already does this.
      
      With CONFIG_PREEMPT="y" the lock loops are coded with _raw_spin_trylock,
      _raw_read_trylock and _raw_write_trylock in kernel/spinlock.c.  If the lock
      could not be taken cpu_relax is called.  A directed yield is not possible
      because cpu_relax doesn't know anything about the lock.  To be able to
      yield the lock in favour of the current lock holder variants of cpu_relax
      for spinlocks and rw-locks are needed.  The new _raw_spin_relax,
      _raw_read_relax and _raw_write_relax primitives differ from cpu_relax
      insofar that they have an argument: a pointer to the lock structure.
      Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      ef6edc97
  4. 27 9月, 2006 1 次提交
  5. 26 9月, 2006 3 次提交
    • A
      [PATCH] Clean up spin/rwlocks · 8b059d23
      Andi Kleen 提交于
      - Inline spinlock strings into their inline functions
      - Convert macros to typesafe inlines
      - Replace some leftover __asm__ __volatile__s with asm volatile
      Signed-off-by: NAndi Kleen <ak@suse.de>
      8b059d23
    • A
      [PATCH] Don't use lock section for mutexes and semaphores · 8578bdf8
      Andi Kleen 提交于
      Lock sections cannot be handled by the dwarf2 unwinder.
      
      Disadvantage is a taken branch in the hot path.
      Signed-off-by: NAndi Kleen <ak@suse.de>
      8578bdf8
    • A
      [PATCH] Clean up read write lock assembly · 9a0b26e6
      Andi Kleen 提交于
      - Move the slow path fallbacks to their own assembly files
      This makes them much easier to read and is needed for the next change.
      - Add CFI annotations for unwinding (XXX need review)
      - Remove constant case which can never happen with out of line spinlocks
      - Use patchable LOCK prefixes
      - Don't use lock sections anymore for inline code because they can't
      be expressed by the unwinder (this adds one taken jump to the lock
      fast path)
      
      Cc: jbeulich@novell.com
      Signed-off-by: NAndi Kleen <ak@suse.de>
      9a0b26e6
  6. 31 8月, 2006 1 次提交
  7. 27 6月, 2006 1 次提交
    • G
      [PATCH] x86_64: x86_64 version of the smp alternative patch. · d167a518
      Gerd Hoffmann 提交于
      Changes are largely identical to the i386 version:
      
       * alternative #define are moved to the new alternative.h file.
       * one new elf section with pointers to the lock prefixes which can be
         nop'ed out for non-smp.
       * two new elf sections simliar to the "classic" alternatives to
         replace SMP code with simpler UP code.
       * fixup headers to use alternative.h instead of defining their own
         LOCK / LOCK_PREFIX macros.
      
      The patch reuses the i386 version of the alternatives code to avoid code
      duplication.  The code in alternatives.c was shuffled around a bit to
      reduce the number of #ifdefs needed.  It also got some tweaks needed for
      x86_64 (vsyscall page handling) and new features (noreplacement option
      which was x86_64 only up to now).  Debug printk's are changed from
      compile-time to runtime.
      
      Loosely based on a early version from Bastian Blank <waldi@debian.org>
      Signed-off-by: NGerd Hoffmann <kraxel@suse.de>
      Signed-off-by: NAndi Kleen <ak@suse.de>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      d167a518
  8. 26 4月, 2006 1 次提交
  9. 15 11月, 2005 1 次提交
  10. 11 9月, 2005 1 次提交
    • I
      [PATCH] spinlock consolidation · fb1c8f93
      Ingo Molnar 提交于
      This patch (written by me and also containing many suggestions of Arjan van
      de Ven) does a major cleanup of the spinlock code.  It does the following
      things:
      
       - consolidates and enhances the spinlock/rwlock debugging code
      
       - simplifies the asm/spinlock.h files
      
       - encapsulates the raw spinlock type and moves generic spinlock
         features (such as ->break_lock) into the generic code.
      
       - cleans up the spinlock code hierarchy to get rid of the spaghetti.
      
      Most notably there's now only a single variant of the debugging code,
      located in lib/spinlock_debug.c.  (previously we had one SMP debugging
      variant per architecture, plus a separate generic one for UP builds)
      
      Also, i've enhanced the rwlock debugging facility, it will now track
      write-owners.  There is new spinlock-owner/CPU-tracking on SMP builds too.
      All locks have lockup detection now, which will work for both soft and hard
      spin/rwlock lockups.
      
      The arch-level include files now only contain the minimally necessary
      subset of the spinlock code - all the rest that can be generalized now
      lives in the generic headers:
      
       include/asm-i386/spinlock_types.h       |   16
       include/asm-x86_64/spinlock_types.h     |   16
      
      I have also split up the various spinlock variants into separate files,
      making it easier to see which does what. The new layout is:
      
         SMP                         |  UP
         ----------------------------|-----------------------------------
         asm/spinlock_types_smp.h    |  linux/spinlock_types_up.h
         linux/spinlock_types.h      |  linux/spinlock_types.h
         asm/spinlock_smp.h          |  linux/spinlock_up.h
         linux/spinlock_api_smp.h    |  linux/spinlock_api_up.h
         linux/spinlock.h            |  linux/spinlock.h
      
      /*
       * here's the role of the various spinlock/rwlock related include files:
       *
       * on SMP builds:
       *
       *  asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
       *                        initializers
       *
       *  linux/spinlock_types.h:
       *                        defines the generic type and initializers
       *
       *  asm/spinlock.h:       contains the __raw_spin_*()/etc. lowlevel
       *                        implementations, mostly inline assembly code
       *
       *   (also included on UP-debug builds:)
       *
       *  linux/spinlock_api_smp.h:
       *                        contains the prototypes for the _spin_*() APIs.
       *
       *  linux/spinlock.h:     builds the final spin_*() APIs.
       *
       * on UP builds:
       *
       *  linux/spinlock_type_up.h:
       *                        contains the generic, simplified UP spinlock type.
       *                        (which is an empty structure on non-debug builds)
       *
       *  linux/spinlock_types.h:
       *                        defines the generic type and initializers
       *
       *  linux/spinlock_up.h:
       *                        contains the __raw_spin_*()/etc. version of UP
       *                        builds. (which are NOPs on non-debug, non-preempt
       *                        builds)
       *
       *   (included on UP-non-debug builds:)
       *
       *  linux/spinlock_api_up.h:
       *                        builds the _spin_*() APIs.
       *
       *  linux/spinlock.h:     builds the final spin_*() APIs.
       */
      
      All SMP and UP architectures are converted by this patch.
      
      arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via
      crosscompilers.  m32r, mips, sh, sparc, have not been tested yet, but should
      be mostly fine.
      
      From: Grant Grundler <grundler@parisc-linux.org>
      
        Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU).
        Builds 32-bit SMP kernel (not booted or tested).  I did not try to build
        non-SMP kernels.  That should be trivial to fix up later if necessary.
      
        I converted bit ops atomic_hash lock to raw_spinlock_t.  Doing so avoids
        some ugly nesting of linux/*.h and asm/*.h files.  Those particular locks
        are well tested and contained entirely inside arch specific code.  I do NOT
        expect any new issues to arise with them.
      
       If someone does ever need to use debug/metrics with them, then they will
        need to unravel this hairball between spinlocks, atomic ops, and bit ops
        that exist only because parisc has exactly one atomic instruction: LDCW
        (load and clear word).
      
      From: "Luck, Tony" <tony.luck@intel.com>
      
         ia64 fix
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NArjan van de Ven <arjanv@infradead.org>
      Signed-off-by: NGrant Grundler <grundler@parisc-linux.org>
      Cc: Matthew Wilcox <willy@debian.org>
      Signed-off-by: NHirokazu Takata <takata@linux-m32r.org>
      Signed-off-by: NMikael Pettersson <mikpe@csd.uu.se>
      Signed-off-by: NBenoit Boissinot <benoit.boissinot@ens-lyon.org>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      fb1c8f93
  11. 17 4月, 2005 1 次提交
    • L
      Linux-2.6.12-rc2 · 1da177e4
      Linus Torvalds 提交于
      Initial git repository build. I'm not bothering with the full history,
      even though we have it. We can create a separate "historical" git
      archive of that later if we want to, and in the meantime it's about
      3.2GB when imported into git - space that would just make the early
      git days unnecessarily complicated, when we don't have a lot of good
      infrastructure for it.
      
      Let it rip!
      1da177e4