linux/arch/parisc/lib/bitops.c

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/*
* bitops.c: atomic operations which got too long to be inlined all over
* the place.
*
* Copyright 1999 Philipp Rumpf (prumpf@tux.org)
* Copyright 2000 Grant Grundler (grundler@cup.hp.com)
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <asm/system.h>
#include <asm/atomic.h>
#ifdef CONFIG_SMP
[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 <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: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjanv@infradead.org> Signed-off-by: Grant Grundler <grundler@parisc-linux.org> Cc: Matthew Wilcox <willy@debian.org> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se> Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 07:25:56 +00:00
raw_spinlock_t __atomic_hash[ATOMIC_HASH_SIZE] __lock_aligned = {
[0 ... (ATOMIC_HASH_SIZE-1)] = __RAW_SPIN_LOCK_UNLOCKED
};
#endif
#ifdef __LP64__
unsigned long __xchg64(unsigned long x, unsigned long *ptr)
{
unsigned long temp, flags;
_atomic_spin_lock_irqsave(ptr, flags);
temp = *ptr;
*ptr = x;
_atomic_spin_unlock_irqrestore(ptr, flags);
return temp;
}
#endif
unsigned long __xchg32(int x, int *ptr)
{
unsigned long flags;
long temp;
_atomic_spin_lock_irqsave(ptr, flags);
temp = (long) *ptr; /* XXX - sign extension wanted? */
*ptr = x;
_atomic_spin_unlock_irqrestore(ptr, flags);
return (unsigned long)temp;
}
unsigned long __xchg8(char x, char *ptr)
{
unsigned long flags;
long temp;
_atomic_spin_lock_irqsave(ptr, flags);
temp = (long) *ptr; /* XXX - sign extension wanted? */
*ptr = x;
_atomic_spin_unlock_irqrestore(ptr, flags);
return (unsigned long)temp;
}
#ifdef __LP64__
unsigned long __cmpxchg_u64(volatile unsigned long *ptr, unsigned long old, unsigned long new)
{
unsigned long flags;
unsigned long prev;
_atomic_spin_lock_irqsave(ptr, flags);
if ((prev = *ptr) == old)
*ptr = new;
_atomic_spin_unlock_irqrestore(ptr, flags);
return prev;
}
#endif
unsigned long __cmpxchg_u32(volatile unsigned int *ptr, unsigned int old, unsigned int new)
{
unsigned long flags;
unsigned int prev;
_atomic_spin_lock_irqsave(ptr, flags);
if ((prev = *ptr) == old)
*ptr = new;
_atomic_spin_unlock_irqrestore(ptr, flags);
return (unsigned long)prev;
}