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author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-07 19:33:50 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-08-07 19:33:50 +0200 |
commit | 25d8d4eecace9de5a6a2193e4df1917afbdd3052 (patch) | |
tree | 1f1bbde6423745251c41fb4d1842e70b9f7bca07 /arch/powerpc/include/asm/spinlock.h | |
parent | Merge tag 'm68knommu-for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/g... (diff) | |
parent | selftests/powerpc: Fix pkey syscall redefinitions (diff) | |
download | linux-25d8d4eecace9de5a6a2193e4df1917afbdd3052.tar.xz linux-25d8d4eecace9de5a6a2193e4df1917afbdd3052.zip |
Merge tag 'powerpc-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
- Add support for (optionally) using queued spinlocks & rwlocks.
- Support for a new faster system call ABI using the scv instruction on
Power9 or later.
- Drop support for the PROT_SAO mmap/mprotect flag as it will be
unsupported on Power10 and future processors, leaving us with no way
to implement the functionality it requests. This risks breaking
userspace, though we believe it is unused in practice.
- A bug fix for, and then the removal of, our custom stack expansion
checking. We now allow stack expansion up to the rlimit, like other
architectures.
- Remove the remnants of our (previously disabled) topology update
code, which tried to react to NUMA layout changes on virtualised
systems, but was prone to crashes and other problems.
- Add PMU support for Power10 CPUs.
- A change to our signal trampoline so that we don't unbalance the link
stack (branch return predictor) in the signal delivery path.
- Lots of other cleanups, refactorings, smaller features and so on as
usual.
Thanks to: Abhishek Goel, Alastair D'Silva, Alexander A. Klimov, Alexey
Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju
T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Balamuruhan
S, Bharata B Rao, Bill Wendling, Bin Meng, Cédric Le Goater, Chris
Packham, Christophe Leroy, Christoph Hellwig, Daniel Axtens, Dan
Williams, David Lamparter, Desnes A. Nunes do Rosario, Erhard F., Finn
Thain, Frederic Barrat, Ganesh Goudar, Gautham R. Shenoy, Geoff Levand,
Greg Kurz, Gustavo A. R. Silva, Hari Bathini, Harish, Imre Kaloz, Joel
Stanley, Joe Perches, John Crispin, Jordan Niethe, Kajol Jain, Kamalesh
Babulal, Kees Cook, Laurent Dufour, Leonardo Bras, Li RongQing, Madhavan
Srinivasan, Mahesh Salgaonkar, Mark Cave-Ayland, Michal Suchanek, Milton
Miller, Mimi Zohar, Murilo Opsfelder Araujo, Nathan Chancellor, Nathan
Lynch, Naveen N. Rao, Nayna Jain, Nicholas Piggin, Oliver O'Halloran,
Palmer Dabbelt, Pedro Miraglia Franco de Carvalho, Philippe Bergheaud,
Pingfan Liu, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Randy
Dunlap, Ravi Bangoria, Sachin Sant, Sam Bobroff, Sandipan Das, Santosh
Sivaraj, Satheesh Rajendran, Shirisha Ganta, Sourabh Jain, Srikar
Dronamraju, Stan Johnson, Stephen Rothwell, Thadeu Lima de Souza
Cascardo, Thiago Jung Bauermann, Tom Lane, Vaibhav Jain, Vladis Dronov,
Wei Yongjun, Wen Xiong, YueHaibing.
* tag 'powerpc-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (337 commits)
selftests/powerpc: Fix pkey syscall redefinitions
powerpc: Fix circular dependency between percpu.h and mmu.h
powerpc/powernv/sriov: Fix use of uninitialised variable
selftests/powerpc: Skip vmx/vsx/tar/etc tests on older CPUs
powerpc/40x: Fix assembler warning about r0
powerpc/papr_scm: Add support for fetching nvdimm 'fuel-gauge' metric
powerpc/papr_scm: Fetch nvdimm performance stats from PHYP
cpuidle: pseries: Fixup exit latency for CEDE(0)
cpuidle: pseries: Add function to parse extended CEDE records
cpuidle: pseries: Set the latency-hint before entering CEDE
selftests/powerpc: Fix online CPU selection
powerpc/perf: Consolidate perf_callchain_user_[64|32]()
powerpc/pseries/hotplug-cpu: Remove double free in error path
powerpc/pseries/mobility: Add pr_debug() for device tree changes
powerpc/pseries/mobility: Set pr_fmt()
powerpc/cacheinfo: Warn if cache object chain becomes unordered
powerpc/cacheinfo: Improve diagnostics about malformed cache lists
powerpc/cacheinfo: Use name@unit instead of full DT path in debug messages
powerpc/cacheinfo: Set pr_fmt()
powerpc: fix function annotations to avoid section mismatch warnings with gcc-10
...
Diffstat (limited to 'arch/powerpc/include/asm/spinlock.h')
-rw-r--r-- | arch/powerpc/include/asm/spinlock.h | 308 |
1 files changed, 6 insertions, 302 deletions
diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h index 2d620896cdae..6ec72282888d 100644 --- a/arch/powerpc/include/asm/spinlock.h +++ b/arch/powerpc/include/asm/spinlock.h @@ -3,312 +3,16 @@ #define __ASM_SPINLOCK_H #ifdef __KERNEL__ -/* - * Simple spin lock operations. - * - * Copyright (C) 2001-2004 Paul Mackerras <paulus@au.ibm.com>, IBM - * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM - * Copyright (C) 2002 Dave Engebretsen <engebret@us.ibm.com>, IBM - * Rework to support virtual processors - * - * Type of int is used as a full 64b word is not necessary. - * - * (the type definitions are in asm/spinlock_types.h) - */ -#include <linux/jump_label.h> -#include <linux/irqflags.h> -#ifdef CONFIG_PPC64 -#include <asm/paca.h> -#include <asm/hvcall.h> -#endif -#include <asm/synch.h> -#include <asm/ppc-opcode.h> - -#ifdef CONFIG_PPC64 -/* use 0x800000yy when locked, where yy == CPU number */ -#ifdef __BIG_ENDIAN__ -#define LOCK_TOKEN (*(u32 *)(&get_paca()->lock_token)) -#else -#define LOCK_TOKEN (*(u32 *)(&get_paca()->paca_index)) -#endif +#ifdef CONFIG_PPC_QUEUED_SPINLOCKS +#include <asm/qspinlock.h> +#include <asm/qrwlock.h> #else -#define LOCK_TOKEN 1 +#include <asm/simple_spinlock.h> #endif -#ifdef CONFIG_PPC_PSERIES -DECLARE_STATIC_KEY_FALSE(shared_processor); - -#define vcpu_is_preempted vcpu_is_preempted -static inline bool vcpu_is_preempted(int cpu) -{ - if (!static_branch_unlikely(&shared_processor)) - return false; - return !!(be32_to_cpu(lppaca_of(cpu).yield_count) & 1); -} -#endif - -static __always_inline int arch_spin_value_unlocked(arch_spinlock_t lock) -{ - return lock.slock == 0; -} - -static inline int arch_spin_is_locked(arch_spinlock_t *lock) -{ - smp_mb(); - return !arch_spin_value_unlocked(*lock); -} - -/* - * This returns the old value in the lock, so we succeeded - * in getting the lock if the return value is 0. - */ -static inline unsigned long __arch_spin_trylock(arch_spinlock_t *lock) -{ - unsigned long tmp, token; - - token = LOCK_TOKEN; - __asm__ __volatile__( -"1: " PPC_LWARX(%0,0,%2,1) "\n\ - cmpwi 0,%0,0\n\ - bne- 2f\n\ - stwcx. %1,0,%2\n\ - bne- 1b\n" - PPC_ACQUIRE_BARRIER -"2:" - : "=&r" (tmp) - : "r" (token), "r" (&lock->slock) - : "cr0", "memory"); - - return tmp; -} - -static inline int arch_spin_trylock(arch_spinlock_t *lock) -{ - return __arch_spin_trylock(lock) == 0; -} - -/* - * On a system with shared processors (that is, where a physical - * processor is multiplexed between several virtual processors), - * there is no point spinning on a lock if the holder of the lock - * isn't currently scheduled on a physical processor. Instead - * we detect this situation and ask the hypervisor to give the - * rest of our timeslice to the lock holder. - * - * So that we can tell which virtual processor is holding a lock, - * we put 0x80000000 | smp_processor_id() in the lock when it is - * held. Conveniently, we have a word in the paca that holds this - * value. - */ - -#if defined(CONFIG_PPC_SPLPAR) -/* We only yield to the hypervisor if we are in shared processor mode */ -void splpar_spin_yield(arch_spinlock_t *lock); -void splpar_rw_yield(arch_rwlock_t *lock); -#else /* SPLPAR */ -static inline void splpar_spin_yield(arch_spinlock_t *lock) {}; -static inline void splpar_rw_yield(arch_rwlock_t *lock) {}; -#endif - -static inline bool is_shared_processor(void) -{ -#ifdef CONFIG_PPC_SPLPAR - return static_branch_unlikely(&shared_processor); -#else - return false; -#endif -} - -static inline void spin_yield(arch_spinlock_t *lock) -{ - if (is_shared_processor()) - splpar_spin_yield(lock); - else - barrier(); -} - -static inline void rw_yield(arch_rwlock_t *lock) -{ - if (is_shared_processor()) - splpar_rw_yield(lock); - else - barrier(); -} - -static inline void arch_spin_lock(arch_spinlock_t *lock) -{ - while (1) { - if (likely(__arch_spin_trylock(lock) == 0)) - break; - do { - HMT_low(); - if (is_shared_processor()) - splpar_spin_yield(lock); - } while (unlikely(lock->slock != 0)); - HMT_medium(); - } -} - -static inline -void arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags) -{ - unsigned long flags_dis; - - while (1) { - if (likely(__arch_spin_trylock(lock) == 0)) - break; - local_save_flags(flags_dis); - local_irq_restore(flags); - do { - HMT_low(); - if (is_shared_processor()) - splpar_spin_yield(lock); - } while (unlikely(lock->slock != 0)); - HMT_medium(); - local_irq_restore(flags_dis); - } -} -#define arch_spin_lock_flags arch_spin_lock_flags - -static inline void arch_spin_unlock(arch_spinlock_t *lock) -{ - __asm__ __volatile__("# arch_spin_unlock\n\t" - PPC_RELEASE_BARRIER: : :"memory"); - lock->slock = 0; -} - -/* - * Read-write spinlocks, allowing multiple readers - * but only one writer. - * - * NOTE! it is quite common to have readers in interrupts - * but no interrupt writers. For those circumstances we - * can "mix" irq-safe locks - any writer needs to get a - * irq-safe write-lock, but readers can get non-irqsafe - * read-locks. - */ - -#ifdef CONFIG_PPC64 -#define __DO_SIGN_EXTEND "extsw %0,%0\n" -#define WRLOCK_TOKEN LOCK_TOKEN /* it's negative */ -#else -#define __DO_SIGN_EXTEND -#define WRLOCK_TOKEN (-1) +#ifndef CONFIG_PARAVIRT_SPINLOCKS +static inline void pv_spinlocks_init(void) { } #endif -/* - * This returns the old value in the lock + 1, - * so we got a read lock if the return value is > 0. - */ -static inline long __arch_read_trylock(arch_rwlock_t *rw) -{ - long tmp; - - __asm__ __volatile__( -"1: " PPC_LWARX(%0,0,%1,1) "\n" - __DO_SIGN_EXTEND -" addic. %0,%0,1\n\ - ble- 2f\n" -" stwcx. %0,0,%1\n\ - bne- 1b\n" - PPC_ACQUIRE_BARRIER -"2:" : "=&r" (tmp) - : "r" (&rw->lock) - : "cr0", "xer", "memory"); - - return tmp; -} - -/* - * This returns the old value in the lock, - * so we got the write lock if the return value is 0. - */ -static inline long __arch_write_trylock(arch_rwlock_t *rw) -{ - long tmp, token; - - token = WRLOCK_TOKEN; - __asm__ __volatile__( -"1: " PPC_LWARX(%0,0,%2,1) "\n\ - cmpwi 0,%0,0\n\ - bne- 2f\n" -" stwcx. %1,0,%2\n\ - bne- 1b\n" - PPC_ACQUIRE_BARRIER -"2:" : "=&r" (tmp) - : "r" (token), "r" (&rw->lock) - : "cr0", "memory"); - - return tmp; -} - -static inline void arch_read_lock(arch_rwlock_t *rw) -{ - while (1) { - if (likely(__arch_read_trylock(rw) > 0)) - break; - do { - HMT_low(); - if (is_shared_processor()) - splpar_rw_yield(rw); - } while (unlikely(rw->lock < 0)); - HMT_medium(); - } -} - -static inline void arch_write_lock(arch_rwlock_t *rw) -{ - while (1) { - if (likely(__arch_write_trylock(rw) == 0)) - break; - do { - HMT_low(); - if (is_shared_processor()) - splpar_rw_yield(rw); - } while (unlikely(rw->lock != 0)); - HMT_medium(); - } -} - -static inline int arch_read_trylock(arch_rwlock_t *rw) -{ - return __arch_read_trylock(rw) > 0; -} - -static inline int arch_write_trylock(arch_rwlock_t *rw) -{ - return __arch_write_trylock(rw) == 0; -} - -static inline void arch_read_unlock(arch_rwlock_t *rw) -{ - long tmp; - - __asm__ __volatile__( - "# read_unlock\n\t" - PPC_RELEASE_BARRIER -"1: lwarx %0,0,%1\n\ - addic %0,%0,-1\n" -" stwcx. %0,0,%1\n\ - bne- 1b" - : "=&r"(tmp) - : "r"(&rw->lock) - : "cr0", "xer", "memory"); -} - -static inline void arch_write_unlock(arch_rwlock_t *rw) -{ - __asm__ __volatile__("# write_unlock\n\t" - PPC_RELEASE_BARRIER: : :"memory"); - rw->lock = 0; -} - -#define arch_spin_relax(lock) spin_yield(lock) -#define arch_read_relax(lock) rw_yield(lock) -#define arch_write_relax(lock) rw_yield(lock) - -/* See include/linux/spinlock.h */ -#define smp_mb__after_spinlock() smp_mb() - #endif /* __KERNEL__ */ #endif /* __ASM_SPINLOCK_H */ |