From fb1c8f93d869b34cacb8b8932e2b83d96a19d720 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Sat, 10 Sep 2005 00:25:56 -0700 Subject: [PATCH] spinlock consolidation 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 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" ia64 fix Signed-off-by: Ingo Molnar Signed-off-by: Arjan van de Ven Signed-off-by: Grant Grundler Cc: Matthew Wilcox Signed-off-by: Hirokazu Takata Signed-off-by: Mikael Pettersson Signed-off-by: Benoit Boissinot Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/spinlock_api_up.h | 80 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+) create mode 100644 include/linux/spinlock_api_up.h (limited to 'include/linux/spinlock_api_up.h') diff --git a/include/linux/spinlock_api_up.h b/include/linux/spinlock_api_up.h new file mode 100644 index 00000000000..cd81cee566f --- /dev/null +++ b/include/linux/spinlock_api_up.h @@ -0,0 +1,80 @@ +#ifndef __LINUX_SPINLOCK_API_UP_H +#define __LINUX_SPINLOCK_API_UP_H + +#ifndef __LINUX_SPINLOCK_H +# error "please don't include this file directly" +#endif + +/* + * include/linux/spinlock_api_up.h + * + * spinlock API implementation on UP-nondebug (inlined implementation) + * + * portions Copyright 2005, Red Hat, Inc., Ingo Molnar + * Released under the General Public License (GPL). + */ + +#define in_lock_functions(ADDR) 0 + +#define assert_spin_locked(lock) do { (void)(lock); } while (0) + +/* + * In the UP-nondebug case there's no real locking going on, so the + * only thing we have to do is to keep the preempt counts and irq + * flags straight, to supress compiler warnings of unused lock + * variables, and to add the proper checker annotations: + */ +#define __LOCK(lock) \ + do { preempt_disable(); __acquire(lock); (void)(lock); } while (0) + +#define __LOCK_BH(lock) \ + do { local_bh_disable(); __LOCK(lock); } while (0) + +#define __LOCK_IRQ(lock) \ + do { local_irq_disable(); __LOCK(lock); } while (0) + +#define __LOCK_IRQSAVE(lock, flags) \ + do { local_irq_save(flags); __LOCK(lock); } while (0) + +#define __UNLOCK(lock) \ + do { preempt_enable(); __release(lock); (void)(lock); } while (0) + +#define __UNLOCK_BH(lock) \ + do { preempt_enable_no_resched(); local_bh_enable(); __release(lock); (void)(lock); } while (0) + +#define __UNLOCK_IRQ(lock) \ + do { local_irq_enable(); __UNLOCK(lock); } while (0) + +#define __UNLOCK_IRQRESTORE(lock, flags) \ + do { local_irq_restore(flags); __UNLOCK(lock); } while (0) + +#define _spin_lock(lock) __LOCK(lock) +#define _read_lock(lock) __LOCK(lock) +#define _write_lock(lock) __LOCK(lock) +#define _spin_lock_bh(lock) __LOCK_BH(lock) +#define _read_lock_bh(lock) __LOCK_BH(lock) +#define _write_lock_bh(lock) __LOCK_BH(lock) +#define _spin_lock_irq(lock) __LOCK_IRQ(lock) +#define _read_lock_irq(lock) __LOCK_IRQ(lock) +#define _write_lock_irq(lock) __LOCK_IRQ(lock) +#define _spin_lock_irqsave(lock, flags) __LOCK_IRQSAVE(lock, flags) +#define _read_lock_irqsave(lock, flags) __LOCK_IRQSAVE(lock, flags) +#define _write_lock_irqsave(lock, flags) __LOCK_IRQSAVE(lock, flags) +#define _spin_trylock(lock) ({ __LOCK(lock); 1; }) +#define _read_trylock(lock) ({ __LOCK(lock); 1; }) +#define _write_trylock(lock) ({ __LOCK(lock); 1; }) +#define _spin_trylock_bh(lock) ({ __LOCK_BH(lock); 1; }) +#define _spin_unlock(lock) __UNLOCK(lock) +#define _read_unlock(lock) __UNLOCK(lock) +#define _write_unlock(lock) __UNLOCK(lock) +#define _spin_unlock_bh(lock) __UNLOCK_BH(lock) +#define _write_unlock_bh(lock) __UNLOCK_BH(lock) +#define _read_unlock_bh(lock) __UNLOCK_BH(lock) +#define _spin_unlock_irq(lock) __UNLOCK_IRQ(lock) +#define _read_unlock_irq(lock) __UNLOCK_IRQ(lock) +#define _write_unlock_irq(lock) __UNLOCK_IRQ(lock) +#define _spin_unlock_irqrestore(lock, flags) __UNLOCK_IRQRESTORE(lock, flags) +#define _read_unlock_irqrestore(lock, flags) __UNLOCK_IRQRESTORE(lock, flags) +#define _write_unlock_irqrestore(lock, flags) __UNLOCK_IRQRESTORE(lock, flags) + +#endif /* __LINUX_SPINLOCK_API_UP_H */ -- cgit v1.2.3-70-g09d2