diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-06 13:50:15 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-06 13:50:15 -0700 |
commit | 007dc78fea62610bf06829e38f1d8c69b6ea5af6 (patch) | |
tree | 683af90696ed7a237dedd48030bfd649e5822955 /arch | |
parent | 2f1835dffa949f560dfa3ed63c0bfc10944b461c (diff) | |
parent | d671002be6bdd7f77a771e23bf3e95d1f16775e6 (diff) | |
download | linux-007dc78fea62610bf06829e38f1d8c69b6ea5af6.tar.bz2 |
Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
"Here are the locking changes in this cycle:
- rwsem unification and simpler micro-optimizations to prepare for
more intrusive (and more lucrative) scalability improvements in
v5.3 (Waiman Long)
- Lockdep irq state tracking flag usage cleanups (Frederic
Weisbecker)
- static key improvements (Jakub Kicinski, Peter Zijlstra)
- misc updates, cleanups and smaller fixes"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
locking/lockdep: Remove unnecessary unlikely()
locking/static_key: Don't take sleeping locks in __static_key_slow_dec_deferred()
locking/static_key: Factor out the fast path of static_key_slow_dec()
locking/static_key: Add support for deferred static branches
locking/lockdep: Test all incompatible scenarios at once in check_irq_usage()
locking/lockdep: Avoid bogus Clang warning
locking/lockdep: Generate LOCKF_ bit composites
locking/lockdep: Use expanded masks on find_usage_*() functions
locking/lockdep: Map remaining magic numbers to lock usage mask names
locking/lockdep: Move valid_state() inside CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING
locking/rwsem: Prevent unneeded warning during locking selftest
locking/rwsem: Optimize rwsem structure for uncontended lock acquisition
locking/rwsem: Enable lock event counting
locking/lock_events: Don't show pvqspinlock events on bare metal
locking/lock_events: Make lock_events available for all archs & other locks
locking/qspinlock_stat: Introduce generic lockevent_*() counting APIs
locking/rwsem: Enhance DEBUG_RWSEMS_WARN_ON() macro
locking/rwsem: Add debug check for __down_read*()
locking/rwsem: Micro-optimize rwsem_try_read_lock_unqueued()
locking/rwsem: Move rwsem internal function declarations to rwsem-xadd.h
...
Diffstat (limited to 'arch')
40 files changed, 10 insertions, 918 deletions
diff --git a/arch/Kconfig b/arch/Kconfig index a826843470ed..3ab446bd12ef 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -907,6 +907,15 @@ config HAVE_ARCH_PREL32_RELOCATIONS config ARCH_USE_MEMREMAP_PROT bool +config LOCK_EVENT_COUNTS + bool "Locking event counts collection" + depends on DEBUG_FS + ---help--- + Enable light-weight counting of various locking related events + in the system with minimal performance impact. This reduces + the chance of application behavior change because of timing + differences. The counts are reported via debugfs. + source "kernel/gcov/Kconfig" source "scripts/gcc-plugins/Kconfig" diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig index c7c976eb6407..f7b19b813a70 100644 --- a/arch/alpha/Kconfig +++ b/arch/alpha/Kconfig @@ -50,13 +50,6 @@ config MMU bool default y -config RWSEM_GENERIC_SPINLOCK - bool - -config RWSEM_XCHGADD_ALGORITHM - bool - default y - config ARCH_HAS_ILOG2_U32 bool default n diff --git a/arch/alpha/include/asm/rwsem.h b/arch/alpha/include/asm/rwsem.h deleted file mode 100644 index cf8fc8f9a2ed..000000000000 --- a/arch/alpha/include/asm/rwsem.h +++ /dev/null @@ -1,211 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifndef _ALPHA_RWSEM_H -#define _ALPHA_RWSEM_H - -/* - * Written by Ivan Kokshaysky <ink@jurassic.park.msu.ru>, 2001. - * Based on asm-alpha/semaphore.h and asm-i386/rwsem.h - */ - -#ifndef _LINUX_RWSEM_H -#error "please don't include asm/rwsem.h directly, use linux/rwsem.h instead" -#endif - -#ifdef __KERNEL__ - -#include <linux/compiler.h> - -#define RWSEM_UNLOCKED_VALUE 0x0000000000000000L -#define RWSEM_ACTIVE_BIAS 0x0000000000000001L -#define RWSEM_ACTIVE_MASK 0x00000000ffffffffL -#define RWSEM_WAITING_BIAS (-0x0000000100000000L) -#define RWSEM_ACTIVE_READ_BIAS RWSEM_ACTIVE_BIAS -#define RWSEM_ACTIVE_WRITE_BIAS (RWSEM_WAITING_BIAS + RWSEM_ACTIVE_BIAS) - -static inline int ___down_read(struct rw_semaphore *sem) -{ - long oldcount; -#ifndef CONFIG_SMP - oldcount = sem->count.counter; - sem->count.counter += RWSEM_ACTIVE_READ_BIAS; -#else - long temp; - __asm__ __volatile__( - "1: ldq_l %0,%1\n" - " addq %0,%3,%2\n" - " stq_c %2,%1\n" - " beq %2,2f\n" - " mb\n" - ".subsection 2\n" - "2: br 1b\n" - ".previous" - :"=&r" (oldcount), "=m" (sem->count), "=&r" (temp) - :"Ir" (RWSEM_ACTIVE_READ_BIAS), "m" (sem->count) : "memory"); -#endif - return (oldcount < 0); -} - -static inline void __down_read(struct rw_semaphore *sem) -{ - if (unlikely(___down_read(sem))) - rwsem_down_read_failed(sem); -} - -static inline int __down_read_killable(struct rw_semaphore *sem) -{ - if (unlikely(___down_read(sem))) - if (IS_ERR(rwsem_down_read_failed_killable(sem))) - return -EINTR; - - return 0; -} - -/* - * trylock for reading -- returns 1 if successful, 0 if contention - */ -static inline int __down_read_trylock(struct rw_semaphore *sem) -{ - long old, new, res; - - res = atomic_long_read(&sem->count); - do { - new = res + RWSEM_ACTIVE_READ_BIAS; - if (new <= 0) - break; - old = res; - res = atomic_long_cmpxchg(&sem->count, old, new); - } while (res != old); - return res >= 0 ? 1 : 0; -} - -static inline long ___down_write(struct rw_semaphore *sem) -{ - long oldcount; -#ifndef CONFIG_SMP - oldcount = sem->count.counter; - sem->count.counter += RWSEM_ACTIVE_WRITE_BIAS; -#else - long temp; - __asm__ __volatile__( - "1: ldq_l %0,%1\n" - " addq %0,%3,%2\n" - " stq_c %2,%1\n" - " beq %2,2f\n" - " mb\n" - ".subsection 2\n" - "2: br 1b\n" - ".previous" - :"=&r" (oldcount), "=m" (sem->count), "=&r" (temp) - :"Ir" (RWSEM_ACTIVE_WRITE_BIAS), "m" (sem->count) : "memory"); -#endif - return oldcount; -} - -static inline void __down_write(struct rw_semaphore *sem) -{ - if (unlikely(___down_write(sem))) - rwsem_down_write_failed(sem); -} - -static inline int __down_write_killable(struct rw_semaphore *sem) -{ - if (unlikely(___down_write(sem))) { - if (IS_ERR(rwsem_down_write_failed_killable(sem))) - return -EINTR; - } - - return 0; -} - -/* - * trylock for writing -- returns 1 if successful, 0 if contention - */ -static inline int __down_write_trylock(struct rw_semaphore *sem) -{ - long ret = atomic_long_cmpxchg(&sem->count, RWSEM_UNLOCKED_VALUE, - RWSEM_ACTIVE_WRITE_BIAS); - if (ret == RWSEM_UNLOCKED_VALUE) - return 1; - return 0; -} - -static inline void __up_read(struct rw_semaphore *sem) -{ - long oldcount; -#ifndef CONFIG_SMP - oldcount = sem->count.counter; - sem->count.counter -= RWSEM_ACTIVE_READ_BIAS; -#else - long temp; - __asm__ __volatile__( - " mb\n" - "1: ldq_l %0,%1\n" - " subq %0,%3,%2\n" - " stq_c %2,%1\n" - " beq %2,2f\n" - ".subsection 2\n" - "2: br 1b\n" - ".previous" - :"=&r" (oldcount), "=m" (sem->count), "=&r" (temp) - :"Ir" (RWSEM_ACTIVE_READ_BIAS), "m" (sem->count) : "memory"); -#endif - if (unlikely(oldcount < 0)) - if ((int)oldcount - RWSEM_ACTIVE_READ_BIAS == 0) - rwsem_wake(sem); -} - -static inline void __up_write(struct rw_semaphore *sem) -{ - long count; -#ifndef CONFIG_SMP - sem->count.counter -= RWSEM_ACTIVE_WRITE_BIAS; - count = sem->count.counter; -#else - long temp; - __asm__ __volatile__( - " mb\n" - "1: ldq_l %0,%1\n" - " subq %0,%3,%2\n" - " stq_c %2,%1\n" - " beq %2,2f\n" - " subq %0,%3,%0\n" - ".subsection 2\n" - "2: br 1b\n" - ".previous" - :"=&r" (count), "=m" (sem->count), "=&r" (temp) - :"Ir" (RWSEM_ACTIVE_WRITE_BIAS), "m" (sem->count) : "memory"); -#endif - if (unlikely(count)) - if ((int)count == 0) - rwsem_wake(sem); -} - -/* - * downgrade write lock to read lock - */ -static inline void __downgrade_write(struct rw_semaphore *sem) -{ - long oldcount; -#ifndef CONFIG_SMP - oldcount = sem->count.counter; - sem->count.counter -= RWSEM_WAITING_BIAS; -#else - long temp; - __asm__ __volatile__( - "1: ldq_l %0,%1\n" - " addq %0,%3,%2\n" - " stq_c %2,%1\n" - " beq %2,2f\n" - " mb\n" - ".subsection 2\n" - "2: br 1b\n" - ".previous" - :"=&r" (oldcount), "=m" (sem->count), "=&r" (temp) - :"Ir" (-RWSEM_WAITING_BIAS), "m" (sem->count) : "memory"); -#endif - if (unlikely(oldcount < 0)) - rwsem_downgrade_wake(sem); -} - -#endif /* __KERNEL__ */ -#endif /* _ALPHA_RWSEM_H */ diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index c781e45d1d99..23e063df5d2c 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -63,9 +63,6 @@ config SCHED_OMIT_FRAME_POINTER config GENERIC_CSUM def_bool y -config RWSEM_GENERIC_SPINLOCK - def_bool y - config ARCH_DISCONTIGMEM_ENABLE def_bool n diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 9aed25a6019b..dc9855c4a3b4 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -178,10 +178,6 @@ config TRACE_IRQFLAGS_SUPPORT bool default !CPU_V7M -config RWSEM_XCHGADD_ALGORITHM - bool - default y - config ARCH_HAS_ILOG2_U32 bool diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild index a8a4eb7f6dae..8fb51b7bf1d5 100644 --- a/arch/arm/include/asm/Kbuild +++ b/arch/arm/include/asm/Kbuild @@ -12,7 +12,6 @@ generic-y += mm-arch-hooks.h generic-y += msi.h generic-y += parport.h generic-y += preempt.h -generic-y += rwsem.h generic-y += seccomp.h generic-y += segment.h generic-y += serial.h diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 78d9fafac983..d81adca1b04d 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -236,9 +236,6 @@ config LOCKDEP_SUPPORT config TRACE_IRQFLAGS_SUPPORT def_bool y -config RWSEM_XCHGADD_ALGORITHM - def_bool y - config GENERIC_BUG def_bool y depends on BUG diff --git a/arch/arm64/include/asm/Kbuild b/arch/arm64/include/asm/Kbuild index 1e17ea5c372b..60a933b07001 100644 --- a/arch/arm64/include/asm/Kbuild +++ b/arch/arm64/include/asm/Kbuild @@ -16,7 +16,6 @@ generic-y += mm-arch-hooks.h generic-y += msi.h generic-y += qrwlock.h generic-y += qspinlock.h -generic-y += rwsem.h generic-y += segment.h generic-y += serial.h generic-y += set_memory.h diff --git a/arch/c6x/Kconfig b/arch/c6x/Kconfig index 3bb75e674161..eeb0471268a0 100644 --- a/arch/c6x/Kconfig +++ b/arch/c6x/Kconfig @@ -28,9 +28,6 @@ config MMU config FPU def_bool n -config RWSEM_GENERIC_SPINLOCK - def_bool y - config GENERIC_CALIBRATE_DELAY def_bool y diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig index 725a115759c9..6555d1781132 100644 --- a/arch/csky/Kconfig +++ b/arch/csky/Kconfig @@ -92,9 +92,6 @@ config GENERIC_HWEIGHT config MMU def_bool y -config RWSEM_GENERIC_SPINLOCK - def_bool y - config STACKTRACE_SUPPORT def_bool y diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig index c071da34e081..61c01db6c292 100644 --- a/arch/h8300/Kconfig +++ b/arch/h8300/Kconfig @@ -27,9 +27,6 @@ config H8300 config CPU_BIG_ENDIAN def_bool y -config RWSEM_GENERIC_SPINLOCK - def_bool y - config GENERIC_HWEIGHT def_bool y diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig index ac441680dcc0..3e54a53208d5 100644 --- a/arch/hexagon/Kconfig +++ b/arch/hexagon/Kconfig @@ -65,12 +65,6 @@ config GENERIC_CSUM config GENERIC_IRQ_PROBE def_bool y -config RWSEM_GENERIC_SPINLOCK - def_bool n - -config RWSEM_XCHGADD_ALGORITHM - def_bool y - config GENERIC_HWEIGHT def_bool y diff --git a/arch/hexagon/include/asm/Kbuild b/arch/hexagon/include/asm/Kbuild index d046e8ccdf78..3ff5f297acda 100644 --- a/arch/hexagon/include/asm/Kbuild +++ b/arch/hexagon/include/asm/Kbuild @@ -27,7 +27,6 @@ generic-y += mm-arch-hooks.h generic-y += pci.h generic-y += percpu.h generic-y += preempt.h -generic-y += rwsem.h generic-y += sections.h generic-y += segment.h generic-y += serial.h diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index 8d7396bd1790..73a26f04644e 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -83,10 +83,6 @@ config STACKTRACE_SUPPORT config GENERIC_LOCKBREAK def_bool n -config RWSEM_XCHGADD_ALGORITHM - bool - default y - config HUGETLB_PAGE_SIZE_VARIABLE bool depends on HUGETLB_PAGE diff --git a/arch/ia64/include/asm/rwsem.h b/arch/ia64/include/asm/rwsem.h deleted file mode 100644 index 917910607e0e..000000000000 --- a/arch/ia64/include/asm/rwsem.h +++ /dev/null @@ -1,172 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* - * R/W semaphores for ia64 - * - * Copyright (C) 2003 Ken Chen <kenneth.w.chen@intel.com> - * Copyright (C) 2003 Asit Mallick <asit.k.mallick@intel.com> - * Copyright (C) 2005 Christoph Lameter <cl@linux.com> - * - * Based on asm-i386/rwsem.h and other architecture implementation. - * - * The MSW of the count is the negated number of active writers and - * waiting lockers, and the LSW is the total number of active locks. - * - * The lock count is initialized to 0 (no active and no waiting lockers). - * - * When a writer subtracts WRITE_BIAS, it'll get 0xffffffff00000001 for - * the case of an uncontended lock. Readers increment by 1 and see a positive - * value when uncontended, negative if there are writers (and maybe) readers - * waiting (in which case it goes to sleep). - */ - -#ifndef _ASM_IA64_RWSEM_H -#define _ASM_IA64_RWSEM_H - -#ifndef _LINUX_RWSEM_H -#error "Please don't include <asm/rwsem.h> directly, use <linux/rwsem.h> instead." -#endif - -#include <asm/intrinsics.h> - -#define RWSEM_UNLOCKED_VALUE __IA64_UL_CONST(0x0000000000000000) -#define RWSEM_ACTIVE_BIAS (1L) -#define RWSEM_ACTIVE_MASK (0xffffffffL) -#define RWSEM_WAITING_BIAS (-0x100000000L) -#define RWSEM_ACTIVE_READ_BIAS RWSEM_ACTIVE_BIAS -#define RWSEM_ACTIVE_WRITE_BIAS (RWSEM_WAITING_BIAS + RWSEM_ACTIVE_BIAS) - -/* - * lock for reading - */ -static inline int -___down_read (struct rw_semaphore *sem) -{ - long result = ia64_fetchadd8_acq((unsigned long *)&sem->count.counter, 1); - - return (result < 0); -} - -static inline void -__down_read (struct rw_semaphore *sem) -{ - if (___down_read(sem)) - rwsem_down_read_failed(sem); -} - -static inline int -__down_read_killable (struct rw_semaphore *sem) -{ - if (___down_read(sem)) - if (IS_ERR(rwsem_down_read_failed_killable(sem))) - return -EINTR; - - return 0; -} - -/* - * lock for writing - */ -static inline long -___down_write (struct rw_semaphore *sem) -{ - long old, new; - - do { - old = atomic_long_read(&sem->count); - new = old + RWSEM_ACTIVE_WRITE_BIAS; - } while (atomic_long_cmpxchg_acquire(&sem->count, old, new) != old); - - return old; -} - -static inline void -__down_write (struct rw_semaphore *sem) -{ - if (___down_write(sem)) - rwsem_down_write_failed(sem); -} - -static inline int -__down_write_killable (struct rw_semaphore *sem) -{ - if (___down_write(sem)) { - if (IS_ERR(rwsem_down_write_failed_killable(sem))) - return -EINTR; - } - - return 0; -} - -/* - * unlock after reading - */ -static inline void -__up_read (struct rw_semaphore *sem) -{ - long result = ia64_fetchadd8_rel((unsigned long *)&sem->count.counter, -1); - - if (result < 0 && (--result & RWSEM_ACTIVE_MASK) == 0) - rwsem_wake(sem); -} - -/* - * unlock after writing - */ -static inline void -__up_write (struct rw_semaphore *sem) -{ - long old, new; - - do { - old = atomic_long_read(&sem->count); - new = old - RWSEM_ACTIVE_WRITE_BIAS; - } while (atomic_long_cmpxchg_release(&sem->count, old, new) != old); - - if (new < 0 && (new & RWSEM_ACTIVE_MASK) == 0) - rwsem_wake(sem); -} - -/* - * trylock for reading -- returns 1 if successful, 0 if contention - */ -static inline int -__down_read_trylock (struct rw_semaphore *sem) -{ - long tmp; - while ((tmp = atomic_long_read(&sem->count)) >= 0) { - if (tmp == atomic_long_cmpxchg_acquire(&sem->count, tmp, tmp+1)) { - return 1; - } - } - return 0; -} - -/* - * trylock for writing -- returns 1 if successful, 0 if contention - */ -static inline int -__down_write_trylock (struct rw_semaphore *sem) -{ - long tmp = atomic_long_cmpxchg_acquire(&sem->count, - RWSEM_UNLOCKED_VALUE, RWSEM_ACTIVE_WRITE_BIAS); - return tmp == RWSEM_UNLOCKED_VALUE; -} - -/* - * downgrade write lock to read lock - */ -static inline void -__downgrade_write (struct rw_semaphore *sem) -{ - long old, new; - - do { - old = atomic_long_read(&sem->count); - new = old - RWSEM_WAITING_BIAS; - } while (atomic_long_cmpxchg_release(&sem->count, old, new) != old); - - if (old < 0) - rwsem_downgrade_wake(sem); -} - -#endif /* _ASM_IA64_RWSEM_H */ diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index 4e37efbc9296..735b9679fe6f 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -33,13 +33,6 @@ config M68K config CPU_BIG_ENDIAN def_bool y -config RWSEM_GENERIC_SPINLOCK - bool - default y - -config RWSEM_XCHGADD_ALGORITHM - bool - config ARCH_HAS_ILOG2_U32 bool diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig index 321e398ab6b5..adb179f519f9 100644 --- a/arch/microblaze/Kconfig +++ b/arch/microblaze/Kconfig @@ -59,15 +59,9 @@ config CPU_LITTLE_ENDIAN endchoice -config RWSEM_GENERIC_SPINLOCK - def_bool y - config ZONE_DMA def_bool y -config RWSEM_XCHGADD_ALGORITHM - bool - config ARCH_HAS_ILOG2_U32 def_bool n diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 4a5f5b0ee9a9..b9c48b27162d 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1037,13 +1037,6 @@ source "arch/mips/paravirt/Kconfig" endmenu -config RWSEM_GENERIC_SPINLOCK - bool - default y - -config RWSEM_XCHGADD_ALGORITHM - bool - config GENERIC_HWEIGHT bool default y diff --git a/arch/nds32/Kconfig b/arch/nds32/Kconfig index addb7f5f5264..55559ca0efe4 100644 --- a/arch/nds32/Kconfig +++ b/arch/nds32/Kconfig @@ -60,9 +60,6 @@ config GENERIC_LOCKBREAK def_bool y depends on PREEMPT -config RWSEM_GENERIC_SPINLOCK - def_bool y - config TRACE_IRQFLAGS_SUPPORT def_bool y diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig index 3633f8144367..ea37394ff3ea 100644 --- a/arch/nios2/Kconfig +++ b/arch/nios2/Kconfig @@ -41,9 +41,6 @@ config NO_IOPORT_MAP config FPU def_bool n -config RWSEM_GENERIC_SPINLOCK - def_bool y - config TRACE_IRQFLAGS_SUPPORT def_bool n diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig index c6cf8a49a0ab..7cfb20555b10 100644 --- a/arch/openrisc/Kconfig +++ b/arch/openrisc/Kconfig @@ -44,12 +44,6 @@ config CPU_BIG_ENDIAN config MMU def_bool y -config RWSEM_GENERIC_SPINLOCK - def_bool y - -config RWSEM_XCHGADD_ALGORITHM - def_bool n - config GENERIC_HWEIGHT def_bool y diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index c8e621296092..f1ed8ddfe486 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -75,12 +75,6 @@ config GENERIC_LOCKBREAK default y depends on SMP && PREEMPT -config RWSEM_GENERIC_SPINLOCK - def_bool y - -config RWSEM_XCHGADD_ALGORITHM - bool - config ARCH_HAS_ILOG2_U32 bool default n diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 8e1e2abf17eb..fab0bf4259c7 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -103,13 +103,6 @@ config LOCKDEP_SUPPORT bool default y -config RWSEM_GENERIC_SPINLOCK - bool - -config RWSEM_XCHGADD_ALGORITHM - bool - default y - config GENERIC_LOCKBREAK bool default y diff --git a/arch/powerpc/include/asm/Kbuild b/arch/powerpc/include/asm/Kbuild index a0c132bedfae..36bda391e549 100644 --- a/arch/powerpc/include/asm/Kbuild +++ b/arch/powerpc/include/asm/Kbuild @@ -8,6 +8,5 @@ generic-y += irq_regs.h generic-y += local64.h generic-y += mcs_spinlock.h generic-y += preempt.h -generic-y += rwsem.h generic-y += vtime.h generic-y += msi.h diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index eb56c82d8aa1..0582260fb6c2 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -69,9 +69,6 @@ config STACKTRACE_SUPPORT config TRACE_IRQFLAGS_SUPPORT def_bool y -config RWSEM_GENERIC_SPINLOCK - def_bool y - config GENERIC_BUG def_bool y depends on BUG diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index cf06e313e103..97b555e772d7 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -14,12 +14,6 @@ config LOCKDEP_SUPPORT config STACKTRACE_SUPPORT def_bool y -config RWSEM_GENERIC_SPINLOCK - bool - -config RWSEM_XCHGADD_ALGORITHM - def_bool y - config ARCH_HAS_ILOG2_U32 def_bool n diff --git a/arch/s390/include/asm/Kbuild b/arch/s390/include/asm/Kbuild index 12d77cb11fe5..d5fadefea33c 100644 --- a/arch/s390/include/asm/Kbuild +++ b/arch/s390/include/asm/Kbuild @@ -20,7 +20,6 @@ generic-y += local.h generic-y += local64.h generic-y += mcs_spinlock.h generic-y += mm-arch-hooks.h -generic-y += rwsem.h generic-y += trace_clock.h generic-y += unaligned.h generic-y += word-at-a-time.h diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig index b1c91ea9a958..0be08d586d40 100644 --- a/arch/sh/Kconfig +++ b/arch/sh/Kconfig @@ -90,12 +90,6 @@ config ARCH_DEFCONFIG default "arch/sh/configs/shx3_defconfig" if SUPERH32 default "arch/sh/configs/cayman_defconfig" if SUPERH64 -config RWSEM_GENERIC_SPINLOCK - def_bool y - -config RWSEM_XCHGADD_ALGORITHM - bool - config GENERIC_BUG def_bool y depends on BUG && SUPERH32 diff --git a/arch/sh/include/asm/Kbuild b/arch/sh/include/asm/Kbuild index 7bf2cb680d32..73fff39a0122 100644 --- a/arch/sh/include/asm/Kbuild +++ b/arch/sh/include/asm/Kbuild @@ -17,7 +17,6 @@ generic-y += mm-arch-hooks.h generic-y += parport.h generic-y += percpu.h generic-y += preempt.h -generic-y += rwsem.h generic-y += serial.h generic-y += sizes.h generic-y += trace_clock.h diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index db79290ed6d5..f6421c9ce5d3 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -192,14 +192,6 @@ config NR_CPUS source "kernel/Kconfig.hz" -config RWSEM_GENERIC_SPINLOCK - bool - default y if SPARC32 - -config RWSEM_XCHGADD_ALGORITHM - bool - default y if SPARC64 - config GENERIC_HWEIGHT bool default y diff --git a/arch/sparc/include/asm/Kbuild b/arch/sparc/include/asm/Kbuild index a22cfd5c0ee8..2ca3200d3616 100644 --- a/arch/sparc/include/asm/Kbuild +++ b/arch/sparc/include/asm/Kbuild @@ -18,7 +18,6 @@ generic-y += mm-arch-hooks.h generic-y += module.h generic-y += msi.h generic-y += preempt.h -generic-y += rwsem.h generic-y += serial.h generic-y += trace_clock.h generic-y += word-at-a-time.h diff --git a/arch/unicore32/Kconfig b/arch/unicore32/Kconfig index d83c8f70900d..2445dfcf6444 100644 --- a/arch/unicore32/Kconfig +++ b/arch/unicore32/Kconfig @@ -39,12 +39,6 @@ config STACKTRACE_SUPPORT config LOCKDEP_SUPPORT def_bool y -config RWSEM_GENERIC_SPINLOCK - def_bool y - -config RWSEM_XCHGADD_ALGORITHM - bool - config ARCH_HAS_ILOG2_U32 bool diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index f1162df4a805..90e2640ade75 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -268,9 +268,6 @@ config ARCH_MAY_HAVE_PC_FDC def_bool y depends on ISA_DMA_API -config RWSEM_XCHGADD_ALGORITHM - def_bool y - config GENERIC_CALIBRATE_DELAY def_bool y @@ -783,14 +780,6 @@ config PARAVIRT_SPINLOCKS If you are unsure how to answer this question, answer Y. -config QUEUED_LOCK_STAT - bool "Paravirt queued spinlock statistics" - depends on PARAVIRT_SPINLOCKS && DEBUG_FS - ---help--- - Enable the collection of statistical data on the slowpath - behavior of paravirtualized queued spinlocks and report - them on debugfs. - source "arch/x86/xen/Kconfig" config KVM_GUEST diff --git a/arch/x86/include/asm/rwsem.h b/arch/x86/include/asm/rwsem.h deleted file mode 100644 index 4c25cf6caefa..000000000000 --- a/arch/x86/include/asm/rwsem.h +++ /dev/null @@ -1,237 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -/* rwsem.h: R/W semaphores implemented using XADD/CMPXCHG for i486+ - * - * Written by David Howells (dhowells@redhat.com). - * - * Derived from asm-x86/semaphore.h - * - * - * The MSW of the count is the negated number of active writers and waiting - * lockers, and the LSW is the total number of active locks - * - * The lock count is initialized to 0 (no active and no waiting lockers). - * - * When a writer subtracts WRITE_BIAS, it'll get 0xffff0001 for the case of an - * uncontended lock. This can be determined because XADD returns the old value. - * Readers increment by 1 and see a positive value when uncontended, negative - * if there are writers (and maybe) readers waiting (in which case it goes to - * sleep). - * - * The value of WAITING_BIAS supports up to 32766 waiting processes. This can - * be extended to 65534 by manually checking the whole MSW rather than relying - * on the S flag. - * - * The value of ACTIVE_BIAS supports up to 65535 active processes. - * - * This should be totally fair - if anything is waiting, a process that wants a - * lock will go to the back of the queue. When the currently active lock is - * released, if there's a writer at the front of the queue, then that and only - * that will be woken up; if there's a bunch of consecutive readers at the - * front, then they'll all be woken up, but no other readers will be. - */ - -#ifndef _ASM_X86_RWSEM_H -#define _ASM_X86_RWSEM_H - -#ifndef _LINUX_RWSEM_H -#error "please don't include asm/rwsem.h directly, use linux/rwsem.h instead" -#endif - -#ifdef __KERNEL__ -#include <asm/asm.h> - -/* - * The bias values and the counter type limits the number of - * potential readers/writers to 32767 for 32 bits and 2147483647 - * for 64 bits. - */ - -#ifdef CONFIG_X86_64 -# define RWSEM_ACTIVE_MASK 0xffffffffL -#else -# define RWSEM_ACTIVE_MASK 0x0000ffffL -#endif - -#define RWSEM_UNLOCKED_VALUE 0x00000000L -#define RWSEM_ACTIVE_BIAS 0x00000001L -#define RWSEM_WAITING_BIAS (-RWSEM_ACTIVE_MASK-1) -#define RWSEM_ACTIVE_READ_BIAS RWSEM_ACTIVE_BIAS -#define RWSEM_ACTIVE_WRITE_BIAS (RWSEM_WAITING_BIAS + RWSEM_ACTIVE_BIAS) - -/* - * lock for reading - */ -#define ____down_read(sem, slow_path) \ -({ \ - struct rw_semaphore* ret; \ - asm volatile("# beginning down_read\n\t" \ - LOCK_PREFIX _ASM_INC "(%[sem])\n\t" \ - /* adds 0x00000001 */ \ - " jns 1f\n" \ - " call " slow_path "\n" \ - "1:\n\t" \ - "# ending down_read\n\t" \ - : "+m" (sem->count), "=a" (ret), \ - ASM_CALL_CONSTRAINT \ - : [sem] "a" (sem) \ - : "memory", "cc"); \ - ret; \ -}) - -static inline void __down_read(struct rw_semaphore *sem) -{ - ____down_read(sem, "call_rwsem_down_read_failed"); -} - -static inline int __down_read_killable(struct rw_semaphore *sem) -{ - if (IS_ERR(____down_read(sem, "call_rwsem_down_read_failed_killable"))) - return -EINTR; - return 0; -} - -/* - * trylock for reading -- returns 1 if successful, 0 if contention - */ -static inline bool __down_read_trylock(struct rw_semaphore *sem) -{ - long result, tmp; - asm volatile("# beginning __down_read_trylock\n\t" - " mov %[count],%[result]\n\t" - "1:\n\t" - " mov %[result],%[tmp]\n\t" - " add %[inc],%[tmp]\n\t" - " jle 2f\n\t" - LOCK_PREFIX " cmpxchg %[tmp],%[count]\n\t" - " jnz 1b\n\t" - "2:\n\t" - "# ending __down_read_trylock\n\t" - : [count] "+m" (sem->count), [result] "=&a" (result), - [tmp] "=&r" (tmp) - : [inc] "i" (RWSEM_ACTIVE_READ_BIAS) - : "memory", "cc"); - return result >= 0; -} - -/* - * lock for writing - */ -#define ____down_write(sem, slow_path) \ -({ \ - long tmp; \ - struct rw_semaphore* ret; \ - \ - asm volatile("# beginning down_write\n\t" \ - LOCK_PREFIX " xadd %[tmp],(%[sem])\n\t" \ - /* adds 0xffff0001, returns the old value */ \ - " test " __ASM_SEL(%w1,%k1) "," __ASM_SEL(%w1,%k1) "\n\t" \ - /* was the active mask 0 before? */\ - " jz 1f\n" \ - " call " slow_path "\n" \ - "1:\n" \ - "# ending down_write" \ - : "+m" (sem->count), [tmp] "=d" (tmp), \ - "=a" (ret), ASM_CALL_CONSTRAINT \ - : [sem] "a" (sem), "[tmp]" (RWSEM_ACTIVE_WRITE_BIAS) \ - : "memory", "cc"); \ - ret; \ -}) - -static inline void __down_write(struct rw_semaphore *sem) -{ - ____down_write(sem, "call_rwsem_down_write_failed"); -} - -static inline int __down_write_killable(struct rw_semaphore *sem) -{ - if (IS_ERR(____down_write(sem, "call_rwsem_down_write_failed_killable"))) - return -EINTR; - - return 0; -} - -/* - * trylock for writing -- returns 1 if successful, 0 if contention - */ -static inline bool __down_write_trylock(struct rw_semaphore *sem) -{ - bool result; - long tmp0, tmp1; - asm volatile("# beginning __down_write_trylock\n\t" - " mov %[count],%[tmp0]\n\t" - "1:\n\t" - " test " __ASM_SEL(%w1,%k1) "," __ASM_SEL(%w1,%k1) "\n\t" - /* was the active mask 0 before? */ - " jnz 2f\n\t" - " mov %[tmp0],%[tmp1]\n\t" - " add %[inc],%[tmp1]\n\t" - LOCK_PREFIX " cmpxchg %[tmp1],%[count]\n\t" - " jnz 1b\n\t" - "2:\n\t" - CC_SET(e) - "# ending __down_write_trylock\n\t" - : [count] "+m" (sem->count), [tmp0] "=&a" (tmp0), - [tmp1] "=&r" (tmp1), CC_OUT(e) (result) - : [inc] "er" (RWSEM_ACTIVE_WRITE_BIAS) - : "memory"); - return result; -} - -/* - * unlock after reading - */ -static inline void __up_read(struct rw_semaphore *sem) -{ - long tmp; - asm volatile("# beginning __up_read\n\t" - LOCK_PREFIX " xadd %[tmp],(%[sem])\n\t" - /* subtracts 1, returns the old value */ - " jns 1f\n\t" - " call call_rwsem_wake\n" /* expects old value in %edx */ - "1:\n" - "# ending __up_read\n" - : "+m" (sem->count), [tmp] "=d" (tmp) - : [sem] "a" (sem), "[tmp]" (-RWSEM_ACTIVE_READ_BIAS) - : "memory", "cc"); -} - -/* - * unlock after writing - */ -static inline void __up_write(struct rw_semaphore *sem) -{ - long tmp; - asm volatile("# beginning __up_write\n\t" - LOCK_PREFIX " xadd %[tmp],(%[sem])\n\t" - /* subtracts 0xffff0001, returns the old value */ - " jns 1f\n\t" - " call call_rwsem_wake\n" /* expects old value in %edx */ - "1:\n\t" - "# ending __up_write\n" - : "+m" (sem->count), [tmp] "=d" (tmp) - : [sem] "a" (sem), "[tmp]" (-RWSEM_ACTIVE_WRITE_BIAS) - : "memory", "cc"); -} - -/* - * downgrade write lock to read lock - */ -static inline void __downgrade_write(struct rw_semaphore *sem) -{ - asm volatile("# beginning __downgrade_write\n\t" - LOCK_PREFIX _ASM_ADD "%[inc],(%[sem])\n\t" - /* - * transitions 0xZZZZ0001 -> 0xYYYY0001 (i386) - * 0xZZZZZZZZ00000001 -> 0xYYYYYYYY00000001 (x86_64) - */ - " jns 1f\n\t" - " call call_rwsem_downgrade_wake\n" - "1:\n\t" - "# ending __downgrade_write\n" - : "+m" (sem->count) - : [sem] "a" (sem), [inc] "er" (-RWSEM_WAITING_BIAS) - : "memory", "cc"); -} - -#endif /* __KERNEL__ */ -#endif /* _ASM_X86_RWSEM_H */ diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile index 3cb3af51ec89..5246db42de45 100644 --- a/arch/x86/lib/Makefile +++ b/arch/x86/lib/Makefile @@ -35,7 +35,6 @@ obj-$(CONFIG_SMP) += msr-smp.o cache-smp.o lib-y := delay.o misc.o cmdline.o cpu.o lib-y += usercopy_$(BITS).o usercopy.o getuser.o putuser.o lib-y += memcpy_$(BITS).o -lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o lib-$(CONFIG_INSTRUCTION_DECODER) += insn.o inat.o insn-eval.o lib-$(CONFIG_RANDOMIZE_BASE) += kaslr.o lib-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o diff --git a/arch/x86/lib/rwsem.S b/arch/x86/lib/rwsem.S deleted file mode 100644 index dc2ab6ea6768..000000000000 --- a/arch/x86/lib/rwsem.S +++ /dev/null @@ -1,156 +0,0 @@ -/* - * x86 semaphore implementation. - * - * (C) Copyright 1999 Linus Torvalds - * - * Portions Copyright 1999 Red Hat, Inc. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - * rw semaphores implemented November 1999 by Benjamin LaHaise <bcrl@kvack.org> - */ - -#include <linux/linkage.h> -#include <asm/alternative-asm.h> -#include <asm/frame.h> - -#define __ASM_HALF_REG(reg) __ASM_SEL(reg, e##reg) -#define __ASM_HALF_SIZE(inst) __ASM_SEL(inst##w, inst##l) - -#ifdef CONFIG_X86_32 - -/* - * The semaphore operations have a special calling sequence that - * allow us to do a simpler in-line version of them. These routines - * need to convert that sequence back into the C sequence when - * there is contention on the semaphore. - * - * %eax contains the semaphore pointer on entry. Save the C-clobbered - * registers (%eax, %edx and %ecx) except %eax which is either a return - * value or just gets clobbered. Same is true for %edx so make sure GCC - * reloads it after the slow path, by making it hold a temporary, for - * example see ____down_write(). - */ - -#define save_common_regs \ - pushl %ecx - -#define restore_common_regs \ - popl %ecx - - /* Avoid uglifying the argument copying x86-64 needs to do. */ - .macro movq src, dst - .endm - -#else - -/* - * x86-64 rwsem wrappers - * - * This interfaces the inline asm code to the slow-path - * C routines. We need to save the call-clobbered regs - * that the asm does not mark as clobbered, and move the - * argument from %rax to %rdi. - * - * NOTE! We don't need to save %rax, because the functions - * will always return the semaphore pointer in %rax (which - * is also the input argument to these helpers) - * - * The following can clobber %rdx because the asm clobbers it: - * call_rwsem_down_write_failed - * call_rwsem_wake - * but %rdi, %rsi, %rcx, %r8-r11 always need saving. - */ - -#define save_common_regs \ - pushq %rdi; \ - pushq %rsi; \ - pushq %rcx; \ - pushq %r8; \ - pushq %r9; \ - pushq %r10; \ - pushq %r11 - -#define restore_common_regs \ - popq %r11; \ - popq %r10; \ - popq %r9; \ - popq %r8; \ - popq %rcx; \ - popq %rsi; \ - popq %rdi - -#endif - -/* Fix up special calling conventions */ -ENTRY(call_rwsem_down_read_failed) - FRAME_BEGIN - save_common_regs - __ASM_SIZE(push,) %__ASM_REG(dx) - movq %rax,%rdi - call rwsem_down_read_failed - __ASM_SIZE(pop,) %__ASM_REG(dx) - restore_common_regs - FRAME_END - ret -ENDPROC(call_rwsem_down_read_failed) - -ENTRY(call_rwsem_down_read_failed_killable) - FRAME_BEGIN - save_common_regs - __ASM_SIZE(push,) %__ASM_REG(dx) - movq %rax,%rdi - call rwsem_down_read_failed_killable - __ASM_SIZE(pop,) %__ASM_REG(dx) - restore_common_regs - FRAME_END - ret -ENDPROC(call_rwsem_down_read_failed_killable) - -ENTRY(call_rwsem_down_write_failed) - FRAME_BEGIN - save_common_regs - movq %rax,%rdi - call rwsem_down_write_failed - restore_common_regs - FRAME_END - ret -ENDPROC(call_rwsem_down_write_failed) - -ENTRY(call_rwsem_down_write_failed_killable) - FRAME_BEGIN - save_common_regs - movq %rax,%rdi - call rwsem_down_write_failed_killable - restore_common_regs - FRAME_END - ret -ENDPROC(call_rwsem_down_write_failed_killable) - -ENTRY(call_rwsem_wake) - FRAME_BEGIN - /* do nothing if still outstanding active readers */ - __ASM_HALF_SIZE(dec) %__ASM_HALF_REG(dx) - jnz 1f - save_common_regs - movq %rax,%rdi - call rwsem_wake - restore_common_regs -1: FRAME_END - ret -ENDPROC(call_rwsem_wake) - -ENTRY(call_rwsem_downgrade_wake) - FRAME_BEGIN - save_common_regs - __ASM_SIZE(push,) %__ASM_REG(dx) - movq %rax,%rdi - call rwsem_downgrade_wake - __ASM_SIZE(pop,) %__ASM_REG(dx) - restore_common_regs - FRAME_END - ret -ENDPROC(call_rwsem_downgrade_wake) diff --git a/arch/x86/um/Kconfig b/arch/x86/um/Kconfig index a9e80e44178c..a8985e1f7432 100644 --- a/arch/x86/um/Kconfig +++ b/arch/x86/um/Kconfig @@ -32,12 +32,6 @@ config ARCH_DEFCONFIG default "arch/um/configs/i386_defconfig" if X86_32 default "arch/um/configs/x86_64_defconfig" if X86_64 -config RWSEM_XCHGADD_ALGORITHM - def_bool 64BIT - -config RWSEM_GENERIC_SPINLOCK - def_bool !RWSEM_XCHGADD_ALGORITHM - config 3_LEVEL_PGTABLES bool "Three-level pagetables" if !64BIT default 64BIT diff --git a/arch/x86/um/Makefile b/arch/x86/um/Makefile index 2d686ae54681..33c51c064c77 100644 --- a/arch/x86/um/Makefile +++ b/arch/x86/um/Makefile @@ -21,14 +21,12 @@ obj-y += checksum_32.o syscalls_32.o obj-$(CONFIG_ELF_CORE) += elfcore.o subarch-y = ../lib/string_32.o ../lib/atomic64_32.o ../lib/atomic64_cx8_32.o -subarch-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += ../lib/rwsem.o else obj-y += syscalls_64.o vdso/ -subarch-y = ../lib/csum-partial_64.o ../lib/memcpy_64.o ../entry/thunk_64.o \ - ../lib/rwsem.o +subarch-y = ../lib/csum-partial_64.o ../lib/memcpy_64.o ../entry/thunk_64.o endif diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index 4b9aafe766c5..35c8d91e6106 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -46,9 +46,6 @@ config XTENSA with reasonable minimum requirements. The Xtensa Linux project has a home page at <http://www.linux-xtensa.org/>. -config RWSEM_XCHGADD_ALGORITHM - def_bool y - config GENERIC_HWEIGHT def_bool y diff --git a/arch/xtensa/include/asm/Kbuild b/arch/xtensa/include/asm/Kbuild index 3843198e03d4..4148090cafb0 100644 --- a/arch/xtensa/include/asm/Kbuild +++ b/arch/xtensa/include/asm/Kbuild @@ -25,7 +25,6 @@ generic-y += percpu.h generic-y += preempt.h generic-y += qrwlock.h generic-y += qspinlock.h -generic-y += rwsem.h generic-y += sections.h generic-y += socket.h generic-y += topology.h |