diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-06 16:57:52 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-06 16:57:52 -0700 |
commit | dd4e5d6106b2380e2c1238406d26df8b2fe1c42c (patch) | |
tree | 33eb172237dd8873de02d5b881bf17cf58d05fab /arch/powerpc | |
parent | 14be4c61c205dcb0a72251c1e2790814181bd9ba (diff) | |
parent | 9726840d9cf0d42377e1591263d7c1d9ae0988ac (diff) |
Merge tag 'arm64-mmiowb' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull mmiowb removal from Will Deacon:
"Remove Mysterious Macro Intended to Obscure Weird Behaviours (mmiowb())
Remove mmiowb() from the kernel memory barrier API and instead, for
architectures that need it, hide the barrier inside spin_unlock() when
MMIO has been performed inside the critical section.
The only relatively recent changes have been addressing review
comments on the documentation, which is in a much better shape thanks
to the efforts of Ben and Ingo.
I was initially planning to split this into two pull requests so that
you could run the coccinelle script yourself, however it's been plain
sailing in linux-next so I've just included the whole lot here to keep
things simple"
* tag 'arm64-mmiowb' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (23 commits)
docs/memory-barriers.txt: Update I/O section to be clearer about CPU vs thread
docs/memory-barriers.txt: Fix style, spacing and grammar in I/O section
arch: Remove dummy mmiowb() definitions from arch code
net/ethernet/silan/sc92031: Remove stale comment about mmiowb()
i40iw: Redefine i40iw_mmiowb() to do nothing
scsi/qla1280: Remove stale comment about mmiowb()
drivers: Remove explicit invocations of mmiowb()
drivers: Remove useless trailing comments from mmiowb() invocations
Documentation: Kill all references to mmiowb()
riscv/mmiowb: Hook up mmwiob() implementation to asm-generic code
powerpc/mmiowb: Hook up mmwiob() implementation to asm-generic code
ia64/mmiowb: Add unconditional mmiowb() to arch_spin_unlock()
mips/mmiowb: Add unconditional mmiowb() to arch_spin_unlock()
sh/mmiowb: Add unconditional mmiowb() to arch_spin_unlock()
m68k/io: Remove useless definition of mmiowb()
nds32/io: Remove useless definition of mmiowb()
x86/io: Remove useless definition of mmiowb()
arm64/io: Remove useless definition of mmiowb()
ARM/io: Remove useless definition of mmiowb()
mmiowb: Hook up mmiowb helpers to spinlocks and generic I/O accessors
...
Diffstat (limited to 'arch/powerpc')
-rw-r--r-- | arch/powerpc/Kconfig | 1 | ||||
-rw-r--r-- | arch/powerpc/include/asm/io.h | 33 | ||||
-rw-r--r-- | arch/powerpc/include/asm/mmiowb.h | 18 | ||||
-rw-r--r-- | arch/powerpc/include/asm/paca.h | 6 | ||||
-rw-r--r-- | arch/powerpc/include/asm/spinlock.h | 17 | ||||
-rw-r--r-- | arch/powerpc/xmon/xmon.c | 5 |
6 files changed, 31 insertions, 49 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 88a4fb3647a2..fa7219ffeadc 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -125,6 +125,7 @@ config PPC select ARCH_HAS_FORTIFY_SOURCE select ARCH_HAS_GCOV_PROFILE_ALL select ARCH_HAS_KCOV + select ARCH_HAS_MMIOWB if PPC64 select ARCH_HAS_PHYS_TO_DMA select ARCH_HAS_PMEM_API if PPC64 select ARCH_HAS_PTE_SPECIAL diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h index 4b73847e9b95..1fad67b46409 100644 --- a/arch/powerpc/include/asm/io.h +++ b/arch/powerpc/include/asm/io.h @@ -34,14 +34,11 @@ extern struct pci_dev *isa_bridge_pcidev; #include <asm/byteorder.h> #include <asm/synch.h> #include <asm/delay.h> +#include <asm/mmiowb.h> #include <asm/mmu.h> #include <asm/ppc_asm.h> #include <asm/pgtable.h> -#ifdef CONFIG_PPC64 -#include <asm/paca.h> -#endif - #define SIO_CONFIG_RA 0x398 #define SIO_CONFIG_RD 0x399 @@ -107,12 +104,6 @@ extern bool isa_io_special; * */ -#ifdef CONFIG_PPC64 -#define IO_SET_SYNC_FLAG() do { local_paca->io_sync = 1; } while(0) -#else -#define IO_SET_SYNC_FLAG() -#endif - #define DEF_MMIO_IN_X(name, size, insn) \ static inline u##size name(const volatile u##size __iomem *addr) \ { \ @@ -127,7 +118,7 @@ static inline void name(volatile u##size __iomem *addr, u##size val) \ { \ __asm__ __volatile__("sync;"#insn" %1,%y0" \ : "=Z" (*addr) : "r" (val) : "memory"); \ - IO_SET_SYNC_FLAG(); \ + mmiowb_set_pending(); \ } #define DEF_MMIO_IN_D(name, size, insn) \ @@ -144,7 +135,7 @@ static inline void name(volatile u##size __iomem *addr, u##size val) \ { \ __asm__ __volatile__("sync;"#insn"%U0%X0 %1,%0" \ : "=m" (*addr) : "r" (val) : "memory"); \ - IO_SET_SYNC_FLAG(); \ + mmiowb_set_pending(); \ } DEF_MMIO_IN_D(in_8, 8, lbz); @@ -652,24 +643,6 @@ static inline void name at \ #include <asm-generic/iomap.h> -#ifdef CONFIG_PPC32 -#define mmiowb() -#else -/* - * Enforce synchronisation of stores vs. spin_unlock - * (this does it explicitly, though our implementation of spin_unlock - * does it implicitely too) - */ -static inline void mmiowb(void) -{ - unsigned long tmp; - - __asm__ __volatile__("sync; li %0,0; stb %0,%1(13)" - : "=&r" (tmp) : "i" (offsetof(struct paca_struct, io_sync)) - : "memory"); -} -#endif /* !CONFIG_PPC32 */ - static inline void iosync(void) { __asm__ __volatile__ ("sync" : : : "memory"); diff --git a/arch/powerpc/include/asm/mmiowb.h b/arch/powerpc/include/asm/mmiowb.h new file mode 100644 index 000000000000..74a00127eb20 --- /dev/null +++ b/arch/powerpc/include/asm/mmiowb.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_POWERPC_MMIOWB_H +#define _ASM_POWERPC_MMIOWB_H + +#ifdef CONFIG_MMIOWB + +#include <linux/compiler.h> +#include <asm/barrier.h> +#include <asm/paca.h> + +#define arch_mmiowb_state() (&local_paca->mmiowb_state) +#define mmiowb() mb() + +#endif /* CONFIG_MMIOWB */ + +#include <asm-generic/mmiowb.h> + +#endif /* _ASM_POWERPC_MMIOWB_H */ diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h index e843bc5d1a0f..134e912d403f 100644 --- a/arch/powerpc/include/asm/paca.h +++ b/arch/powerpc/include/asm/paca.h @@ -34,6 +34,8 @@ #include <asm/cpuidle.h> #include <asm/atomic.h> +#include <asm-generic/mmiowb_types.h> + register struct paca_struct *local_paca asm("r13"); #if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_SMP) @@ -171,7 +173,6 @@ struct paca_struct { u16 trap_save; /* Used when bad stack is encountered */ u8 irq_soft_mask; /* mask for irq soft masking */ u8 irq_happened; /* irq happened while soft-disabled */ - u8 io_sync; /* writel() needs spin_unlock sync */ u8 irq_work_pending; /* IRQ_WORK interrupt while soft-disable */ u8 nap_state_lost; /* NV GPR values lost in power7_idle */ #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE @@ -264,6 +265,9 @@ struct paca_struct { #ifdef CONFIG_STACKPROTECTOR unsigned long canary; #endif +#ifdef CONFIG_MMIOWB + struct mmiowb_state mmiowb_state; +#endif } ____cacheline_aligned; extern void copy_mm_to_paca(struct mm_struct *mm); diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h index 685c72310f5d..15b39c407c4e 100644 --- a/arch/powerpc/include/asm/spinlock.h +++ b/arch/powerpc/include/asm/spinlock.h @@ -39,19 +39,6 @@ #define LOCK_TOKEN 1 #endif -#if defined(CONFIG_PPC64) && defined(CONFIG_SMP) -#define CLEAR_IO_SYNC (get_paca()->io_sync = 0) -#define SYNC_IO do { \ - if (unlikely(get_paca()->io_sync)) { \ - mb(); \ - get_paca()->io_sync = 0; \ - } \ - } while (0) -#else -#define CLEAR_IO_SYNC -#define SYNC_IO -#endif - #ifdef CONFIG_PPC_PSERIES #define vcpu_is_preempted vcpu_is_preempted static inline bool vcpu_is_preempted(int cpu) @@ -99,7 +86,6 @@ static inline unsigned long __arch_spin_trylock(arch_spinlock_t *lock) static inline int arch_spin_trylock(arch_spinlock_t *lock) { - CLEAR_IO_SYNC; return __arch_spin_trylock(lock) == 0; } @@ -130,7 +116,6 @@ extern void __rw_yield(arch_rwlock_t *lock); static inline void arch_spin_lock(arch_spinlock_t *lock) { - CLEAR_IO_SYNC; while (1) { if (likely(__arch_spin_trylock(lock) == 0)) break; @@ -148,7 +133,6 @@ void arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags) { unsigned long flags_dis; - CLEAR_IO_SYNC; while (1) { if (likely(__arch_spin_trylock(lock) == 0)) break; @@ -167,7 +151,6 @@ void arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags) static inline void arch_spin_unlock(arch_spinlock_t *lock) { - SYNC_IO; __asm__ __volatile__("# arch_spin_unlock\n\t" PPC_RELEASE_BARRIER: : :"memory"); lock->slock = 0; diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c index a0f44f992360..13c6a47e6150 100644 --- a/arch/powerpc/xmon/xmon.c +++ b/arch/powerpc/xmon/xmon.c @@ -2429,7 +2429,10 @@ static void dump_one_paca(int cpu) DUMP(p, trap_save, "%#-*x"); DUMP(p, irq_soft_mask, "%#-*x"); DUMP(p, irq_happened, "%#-*x"); - DUMP(p, io_sync, "%#-*x"); +#ifdef CONFIG_MMIOWB + DUMP(p, mmiowb_state.nesting_count, "%#-*x"); + DUMP(p, mmiowb_state.mmiowb_pending, "%#-*x"); +#endif DUMP(p, irq_work_pending, "%#-*x"); DUMP(p, nap_state_lost, "%#-*x"); DUMP(p, sprg_vdso, "%#-*llx"); |