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 --- arch/m32r/kernel/smp.c | 48 ++++++++++++------------------------------------ 1 file changed, 12 insertions(+), 36 deletions(-) (limited to 'arch/m32r/kernel/smp.c') diff --git a/arch/m32r/kernel/smp.c b/arch/m32r/kernel/smp.c index 48b187f2d2b3..a4576ac7e870 100644 --- a/arch/m32r/kernel/smp.c +++ b/arch/m32r/kernel/smp.c @@ -892,7 +892,6 @@ unsigned long send_IPI_mask_phys(cpumask_t physid_mask, int ipi_num, int try) { spinlock_t *ipilock; - unsigned long flags = 0; volatile unsigned long *ipicr_addr; unsigned long ipicr_val; unsigned long my_physid_mask; @@ -916,50 +915,27 @@ unsigned long send_IPI_mask_phys(cpumask_t physid_mask, int ipi_num, * write IPICRi (send IPIi) * unlock ipi_lock[i] */ + spin_lock(ipilock); __asm__ __volatile__ ( - ";; LOCK ipi_lock[i] \n\t" + ";; CHECK IPICRi == 0 \n\t" ".fillinsn \n" "1: \n\t" - "mvfc %1, psw \n\t" - "clrpsw #0x40 -> nop \n\t" - DCACHE_CLEAR("r4", "r5", "%2") - "lock r4, @%2 \n\t" - "addi r4, #-1 \n\t" - "unlock r4, @%2 \n\t" - "mvtc %1, psw \n\t" - "bnez r4, 2f \n\t" - LOCK_SECTION_START(".balign 4 \n\t") - ".fillinsn \n" - "2: \n\t" - "ld r4, @%2 \n\t" - "blez r4, 2b \n\t" + "ld %0, @%1 \n\t" + "and %0, %4 \n\t" + "beqz %0, 2f \n\t" + "bnez %3, 3f \n\t" "bra 1b \n\t" - LOCK_SECTION_END - ";; CHECK IPICRi == 0 \n\t" - ".fillinsn \n" - "3: \n\t" - "ld %0, @%3 \n\t" - "and %0, %6 \n\t" - "beqz %0, 4f \n\t" - "bnez %5, 5f \n\t" - "bra 3b \n\t" ";; WRITE IPICRi (send IPIi) \n\t" ".fillinsn \n" - "4: \n\t" - "st %4, @%3 \n\t" - ";; UNLOCK ipi_lock[i] \n\t" + "2: \n\t" + "st %2, @%1 \n\t" ".fillinsn \n" - "5: \n\t" - "ldi r4, #1 \n\t" - "st r4, @%2 \n\t" + "3: \n\t" : "=&r"(ipicr_val) - : "r"(flags), "r"(&ipilock->slock), "r"(ipicr_addr), - "r"(mask), "r"(try), "r"(my_physid_mask) - : "memory", "r4" -#ifdef CONFIG_CHIP_M32700_TS1 - , "r5" -#endif /* CONFIG_CHIP_M32700_TS1 */ + : "r"(ipicr_addr), "r"(mask), "r"(try), "r"(my_physid_mask) + : "memory" ); + spin_unlock(ipilock); return ipicr_val; } -- cgit v1.2.2