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* powerpc: Rename LWSYNC_ON_SMP to PPC_RELEASE_BARRIER, ISYNC_ON_SMP to ↵Anton Blanchard2010-02-16
| | | | | | | | | | | PPC_ACQUIRE_BARRIER For performance reasons we are about to change ISYNC_ON_SMP to sometimes be lwsync. Now that the macro name doesn't make sense, change it and LWSYNC_ON_SMP to better explain what the barriers are doing. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* powerpc: Use lwarx hint in spinlocksAnton Blanchard2010-02-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Recent versions of the PowerPC architecture added a hint bit to the larx instructions to differentiate between an atomic operation and a lock operation: > 0 Other programs might attempt to modify the word in storage addressed by EA > even if the subsequent Store Conditional succeeds. > > 1 Other programs will not attempt to modify the word in storage addressed by > EA until the program that has acquired the lock performs a subsequent store > releasing the lock. To avoid a binutils dependency this patch create macros for the extended lwarx format and uses it in the spinlock code. To test this change I used a simple test case that acquires and releases a global pthread mutex: pthread_mutex_lock(&mutex); pthread_mutex_unlock(&mutex); On a 32 core POWER6, running 32 test threads we spend almost all our time in the futex spinlock code: 94.37% perf [kernel] [k] ._raw_spin_lock | |--99.95%-- ._raw_spin_lock | | | |--63.29%-- .futex_wake | | | |--36.64%-- .futex_wait_setup Which is a good test for this patch. The results (in lock/unlock operations per second) are: before: 1538203 ops/sec after: 2189219 ops/sec An improvement of 42% A 32 core POWER7 improves even more: before: 1279529 ops/sec after: 2282076 ops/sec An improvement of 78% Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* locking: Convert raw_rwlock functions to arch_rwlockThomas Gleixner2009-12-14
| | | | | | | | | | Name space cleanup for rwlock functions. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
* locking: Convert raw_rwlock to arch_rwlockThomas Gleixner2009-12-14
| | | | | | | | | | | | | | Not strictly necessary for -rt as -rt does not have non sleeping rwlocks, but it's odd to not have a consistent naming convention. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
* locking: Convert __raw_spin* functions to arch_spin*Thomas Gleixner2009-12-14
| | | | | | | | | | Name space cleanup. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
* locking: Convert raw_spinlock to arch_spinlockThomas Gleixner2009-12-14
| | | | | | | | | | | | | | | | | | | The raw_spin* namespace was taken by lockdep for the architecture specific implementations. raw_spin_* would be the ideal name space for the spinlocks which are not converted to sleeping locks in preempt-rt. Linus suggested to convert the raw_ to arch_ locks and cleanup the name space instead of using an artifical name like core_spin, atomic_spin or whatever No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: linux-arch@vger.kernel.org
* locking, powerpc: Rename __spin_try_lock() and friendsHeiko Carstens2009-08-31
| | | | | | | | | | | | | | | | | | | | | | | | Needed to avoid namespace conflicts when the common code function bodies of _spin_try_lock() etc. are moved to a header file where the function name would be __spin_try_lock(). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Horst Hartmann <horsth@linux.vnet.ibm.com> Cc: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: David Miller <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: <linux-arch@vger.kernel.org> LKML-Reference: <20090831124415.918799705@de.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Allow rwlocks to re-enable interruptsRobin Holt2009-04-02
| | | | | | | | | | | | | | | | | Pass the original flags to rwlock arch-code, so that it can re-enable interrupts if implemented for that architecture. Initially, make __raw_read_lock_flags and __raw_write_lock_flags stubs which just do the same thing as non-flags variants. Signed-off-by: Petr Tesarik <ptesarik@suse.cz> Signed-off-by: Robin Holt <holt@sgi.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: <linux-arch@vger.kernel.org> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* powerpc: Tell gcc when we clobber the carry in inline asmPaul Mackerras2008-11-19
| | | | | | | | | | | | We have several instances of inline assembly code that use the addic or addic. instructions, but don't include XER in the list of clobbers. The addic and addic. instructions affect the carry bit, which is in the XER register. This adds "xer" to the list of clobbers for those inline asm statements that use addic or addic. and didn't already have it. Signed-off-by: Paul Mackerras <paulus@samba.org>
* powerpc: Move include files to arch/powerpc/include/asmStephen Rothwell2008-08-03
from include/asm-powerpc. This is the result of a mkdir arch/powerpc/include/asm git mv include/asm-powerpc/* arch/powerpc/include/asm Followed by a few documentation/comment fixups and a couple of places where <asm-powepc/...> was being used explicitly. Of the latter only one was outside the arch code and it is a driver only built for powerpc. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>