Commit f048aace authored by Benjamin Herrenschmidt's avatar Benjamin Herrenschmidt Committed by Paul Mackerras

powerpc/mm: Add SMP support to no-hash TLB handling

This commit moves the whole no-hash TLB handling out of line into a
new tlb_nohash.c file, and implements some basic SMP support using
IPIs and/or broadcast tlbivax instructions.

Note that I'm using local invalidations for D->I cache coherency.

At worst, if another processor is trying to execute the same and
has the old entry in its TLB, it will just take a fault and re-do
the TLB flush locally (it won't re-do the cache flush in any case).
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: default avatarKumar Gala <galak@kernel.crashing.org>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent 7c03d653
......@@ -85,7 +85,7 @@ static inline void *kmap_atomic_prot(struct page *page, enum km_type type, pgpro
BUG_ON(!pte_none(*(kmap_pte-idx)));
#endif
__set_pte_at(&init_mm, vaddr, kmap_pte-idx, mk_pte(page, prot));
local_flush_tlb_page(vaddr);
local_flush_tlb_page(NULL, vaddr);
return (void*) vaddr;
}
......@@ -113,7 +113,7 @@ static inline void kunmap_atomic(void *kvaddr, enum km_type type)
* this pte without first remap it
*/
pte_clear(&init_mm, vaddr, kmap_pte-idx);
local_flush_tlb_page(vaddr);
local_flush_tlb_page(NULL, vaddr);
#endif
pagefault_enable();
}
......
......@@ -30,6 +30,22 @@
*/
#define MMU_FTR_BIG_PHYS ASM_CONST(0x00020000)
/* Enable use of broadcast TLB invalidations. We don't always set it
* on processors that support it due to other constraints with the
* use of such invalidations
*/
#define MMU_FTR_USE_TLBIVAX_BCAST ASM_CONST(0x00040000)
/* Enable use of tlbilx invalidate-by-PID variant.
*/
#define MMU_FTR_USE_TLBILX_PID ASM_CONST(0x00080000)
/* This indicates that the processor cannot handle multiple outstanding
* broadcast tlbivax or tlbsync. This makes the code use a spinlock
* around such invalidate forms.
*/
#define MMU_FTR_LOCK_BCAST_INVAL ASM_CONST(0x00100000)
#ifndef __ASSEMBLY__
#include <asm/cputable.h>
......
......@@ -6,7 +6,9 @@
*
* - flush_tlb_mm(mm) flushes the specified mm context TLB's
* - flush_tlb_page(vma, vmaddr) flushes one page
* - local_flush_tlb_page(vmaddr) flushes one page on the local processor
* - local_flush_tlb_mm(mm) flushes the specified mm context on
* the local processor
* - local_flush_tlb_page(vma, vmaddr) flushes one page on the local processor
* - flush_tlb_page_nohash(vma, vmaddr) flushes one page if SW loaded TLB
* - flush_tlb_range(vma, start, end) flushes a range of pages
* - flush_tlb_kernel_range(start, end) flushes a range of kernel pages
......@@ -18,7 +20,7 @@
*/
#ifdef __KERNEL__
#if defined(CONFIG_4xx) || defined(CONFIG_8xx) || defined(CONFIG_FSL_BOOKE)
#ifdef CONFIG_PPC_MMU_NOHASH
/*
* TLB flushing for software loaded TLB chips
*
......@@ -31,10 +33,10 @@
#define MMU_NO_CONTEXT ((unsigned int)-1)
extern void _tlbie(unsigned long address, unsigned int pid);
extern void _tlbil_all(void);
extern void _tlbil_pid(unsigned int pid);
extern void _tlbil_va(unsigned long address, unsigned int pid);
extern void _tlbivax_bcast(unsigned long address, unsigned int pid);
#if defined(CONFIG_40x) || defined(CONFIG_8xx)
#define _tlbia() asm volatile ("tlbia; sync" : : : "memory")
......@@ -42,48 +44,26 @@ extern void _tlbil_va(unsigned long address, unsigned int pid);
extern void _tlbia(void);
#endif
static inline void local_flush_tlb_mm(struct mm_struct *mm)
{
_tlbil_pid(mm->context.id);
}
static inline void flush_tlb_mm(struct mm_struct *mm)
{
_tlbil_pid(mm->context.id);
}
static inline void local_flush_tlb_page(unsigned long vmaddr)
{
_tlbil_va(vmaddr, 0);
}
static inline void flush_tlb_page(struct vm_area_struct *vma,
unsigned long vmaddr)
{
_tlbil_va(vmaddr, vma ? vma->vm_mm->context.id : 0);
}
extern void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end);
extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
static inline void flush_tlb_page_nohash(struct vm_area_struct *vma,
unsigned long vmaddr)
{
flush_tlb_page(vma, vmaddr);
}
extern void local_flush_tlb_mm(struct mm_struct *mm);
extern void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr);
static inline void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
_tlbil_pid(vma->vm_mm->context.id);
}
#ifdef CONFIG_SMP
extern void flush_tlb_mm(struct mm_struct *mm);
extern void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr);
#else
#define flush_tlb_mm(mm) local_flush_tlb_mm(mm)
#define flush_tlb_page(vma,addr) local_flush_tlb_page(vma,addr)
#endif
#define flush_tlb_page_nohash(vma,addr) flush_tlb_page(vma,addr)
static inline void flush_tlb_kernel_range(unsigned long start,
unsigned long end)
{
_tlbil_pid(0);
}
#elif defined(CONFIG_PPC_STD_MMU_32)
#elif defined(CONFIG_PPC32)
/*
* TLB flushing for "classic" hash-MMMU 32-bit CPUs, 6xx, 7xx, 7xxx
* TLB flushing for "classic" hash-MMU 32-bit CPUs, 6xx, 7xx, 7xxx
*/
extern void _tlbie(unsigned long address);
extern void _tlbia(void);
......@@ -94,14 +74,20 @@ extern void flush_tlb_page_nohash(struct vm_area_struct *vma, unsigned long addr
extern void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end);
extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
static inline void local_flush_tlb_page(unsigned long vmaddr)
static inline void local_flush_tlb_page(struct vm_area_struct *vma,
unsigned long vmaddr)
{
flush_tlb_page(vma, vmaddr);
}
static inline void local_flush_tlb_mm(struct mm_struct *mm)
{
flush_tlb_page(NULL, vmaddr);
flush_tlb_mm(mm);
}
#else
#elif defined(CONFIG_PPC_STD_MMU_64)
/*
* TLB flushing for 64-bit has-MMU CPUs
* TLB flushing for 64-bit hash-MMU CPUs
*/
#include <linux/percpu.h>
......@@ -151,11 +137,16 @@ extern void flush_hash_page(unsigned long va, real_pte_t pte, int psize,
extern void flush_hash_range(unsigned long number, int local);
static inline void local_flush_tlb_mm(struct mm_struct *mm)
{
}
static inline void flush_tlb_mm(struct mm_struct *mm)
{
}
static inline void local_flush_tlb_page(unsigned long vmaddr)
static inline void local_flush_tlb_page(struct vm_area_struct *vma,
unsigned long vmaddr)
{
}
......@@ -183,7 +174,8 @@ static inline void flush_tlb_kernel_range(unsigned long start,
extern void __flush_hash_table_range(struct mm_struct *mm, unsigned long start,
unsigned long end);
#else
#error Unsupported MMU type
#endif
#endif /*__KERNEL__ */
......
......@@ -29,6 +29,7 @@
#include <asm/asm-offsets.h>
#include <asm/processor.h>
#include <asm/kexec.h>
#include <asm/bug.h>
.text
......@@ -496,6 +497,14 @@ _GLOBAL(_tlbil_va)
blr
#endif /* CONFIG_FSL_BOOKE */
/*
* Nobody implements this yet
*/
_GLOBAL(_tlbivax_bcast)
1: trap
EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,0;
blr
/*
* Flush instruction cache.
......
......@@ -116,12 +116,6 @@ EXPORT_SYMBOL(giveup_spe);
#ifndef CONFIG_PPC64
EXPORT_SYMBOL(flush_instruction_cache);
EXPORT_SYMBOL(flush_tlb_kernel_range);
EXPORT_SYMBOL(flush_tlb_page);
EXPORT_SYMBOL(_tlbie);
#if defined(CONFIG_4xx) || defined(CONFIG_8xx) || defined(CONFIG_FSL_BOOKE)
EXPORT_SYMBOL(_tlbil_va);
#endif
#endif
EXPORT_SYMBOL(__flush_icache_range);
EXPORT_SYMBOL(flush_dcache_range);
......
......@@ -9,7 +9,7 @@ endif
obj-y := fault.o mem.o pgtable.o \
init_$(CONFIG_WORD_SIZE).o \
pgtable_$(CONFIG_WORD_SIZE).o
obj-$(CONFIG_PPC_MMU_NOHASH) += mmu_context_nohash.o
obj-$(CONFIG_PPC_MMU_NOHASH) += mmu_context_nohash.o tlb_nohash.o
hash-$(CONFIG_PPC_NATIVE) := hash_native_64.o
obj-$(CONFIG_PPC64) += hash_utils_64.o \
slb_low.o slb.o stab.o \
......
......@@ -284,7 +284,7 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
}
pte_update(ptep, 0, _PAGE_HWEXEC |
_PAGE_ACCESSED);
_tlbie(address, mm->context.id);
local_flush_tlb_page(vma, address);
pte_unmap_unlock(ptep, ptl);
up_read(&mm->mmap_sem);
return 0;
......
......@@ -488,7 +488,7 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
* we invalidate the TLB here, thus avoiding dcbst
* misbehaviour.
*/
_tlbie(address, 0 /* 8xx doesn't care about PID */);
_tlbil_va(address, 0 /* 8xx doesn't care about PID */);
#endif
/* The _PAGE_USER test should really be _PAGE_EXEC, but
* older glibc versions execute some code from no-exec
......
......@@ -137,6 +137,7 @@ void flush_tlb_kernel_range(unsigned long start, unsigned long end)
flush_range(&init_mm, start, end);
FINISH_FLUSH;
}
EXPORT_SYMBOL(flush_tlb_kernel_range);
/*
* Flush all the (user) entries for the address space described by mm.
......@@ -160,6 +161,7 @@ void flush_tlb_mm(struct mm_struct *mm)
flush_range(mp->vm_mm, mp->vm_start, mp->vm_end);
FINISH_FLUSH;
}
EXPORT_SYMBOL(flush_tlb_mm);
void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
{
......@@ -176,6 +178,7 @@ void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
flush_hash_pages(mm->context.id, vmaddr, pmd_val(*pmd), 1);
FINISH_FLUSH;
}
EXPORT_SYMBOL(flush_tlb_page);
/*
* For each address in the range, find the pte for the address
......@@ -188,3 +191,4 @@ void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
flush_range(vma->vm_mm, start, end);
FINISH_FLUSH;
}
EXPORT_SYMBOL(flush_tlb_range);
/*
* This file contains the routines for TLB flushing.
* On machines where the MMU does not use a hash table to store virtual to
* physical translations (ie, SW loaded TLBs or Book3E compilant processors,
* this does -not- include 603 however which shares the implementation with
* hash based processors)
*
* -- BenH
*
* Copyright 2008 Ben Herrenschmidt <benh@kernel.crashing.org>
* IBM Corp.
*
* Derived from arch/ppc/mm/init.c:
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
*
* Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
* and Cort Dougan (PReP) (cort@cs.nmt.edu)
* Copyright (C) 1996 Paul Mackerras
*
* Derived from "arch/i386/mm/init.c"
* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
*
* 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.
*
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/preempt.h>
#include <linux/spinlock.h>
#include <asm/tlbflush.h>
#include <asm/tlb.h>
#include "mmu_decl.h"
/*
* Base TLB flushing operations:
*
* - flush_tlb_mm(mm) flushes the specified mm context TLB's
* - flush_tlb_page(vma, vmaddr) flushes one page
* - flush_tlb_range(vma, start, end) flushes a range of pages
* - flush_tlb_kernel_range(start, end) flushes kernel pages
*
* - local_* variants of page and mm only apply to the current
* processor
*/
/*
* These are the base non-SMP variants of page and mm flushing
*/
void local_flush_tlb_mm(struct mm_struct *mm)
{
unsigned int pid;
preempt_disable();
pid = mm->context.id;
if (pid != MMU_NO_CONTEXT)
_tlbil_pid(pid);
preempt_enable();
}
EXPORT_SYMBOL(local_flush_tlb_mm);
void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
{
unsigned int pid;
preempt_disable();
pid = vma ? vma->vm_mm->context.id : 0;
if (pid != MMU_NO_CONTEXT)
_tlbil_va(vmaddr, pid);
preempt_enable();
}
EXPORT_SYMBOL(local_flush_tlb_page);
/*
* And here are the SMP non-local implementations
*/
#ifdef CONFIG_SMP
static DEFINE_SPINLOCK(tlbivax_lock);
struct tlb_flush_param {
unsigned long addr;
unsigned int pid;
};
static void do_flush_tlb_mm_ipi(void *param)
{
struct tlb_flush_param *p = param;
_tlbil_pid(p ? p->pid : 0);
}
static void do_flush_tlb_page_ipi(void *param)
{
struct tlb_flush_param *p = param;
_tlbil_va(p->addr, p->pid);
}
/* Note on invalidations and PID:
*
* We snapshot the PID with preempt disabled. At this point, it can still
* change either because:
* - our context is being stolen (PID -> NO_CONTEXT) on another CPU
* - we are invaliating some target that isn't currently running here
* and is concurrently acquiring a new PID on another CPU
* - some other CPU is re-acquiring a lost PID for this mm
* etc...
*
* However, this shouldn't be a problem as we only guarantee
* invalidation of TLB entries present prior to this call, so we
* don't care about the PID changing, and invalidating a stale PID
* is generally harmless.
*/
void flush_tlb_mm(struct mm_struct *mm)
{
cpumask_t cpu_mask;
unsigned int pid;
preempt_disable();
pid = mm->context.id;
if (unlikely(pid == MMU_NO_CONTEXT))
goto no_context;
cpu_mask = mm->cpu_vm_mask;
cpu_clear(smp_processor_id(), cpu_mask);
if (!cpus_empty(cpu_mask)) {
struct tlb_flush_param p = { .pid = pid };
smp_call_function_mask(cpu_mask, do_flush_tlb_mm_ipi, &p, 1);
}
_tlbil_pid(pid);
no_context:
preempt_enable();
}
EXPORT_SYMBOL(flush_tlb_mm);
void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
{
cpumask_t cpu_mask;
unsigned int pid;
preempt_disable();
pid = vma ? vma->vm_mm->context.id : 0;
if (unlikely(pid == MMU_NO_CONTEXT))
goto bail;
cpu_mask = vma->vm_mm->cpu_vm_mask;
cpu_clear(smp_processor_id(), cpu_mask);
if (!cpus_empty(cpu_mask)) {
/* If broadcast tlbivax is supported, use it */
if (mmu_has_feature(MMU_FTR_USE_TLBIVAX_BCAST)) {
int lock = mmu_has_feature(MMU_FTR_LOCK_BCAST_INVAL);
if (lock)
spin_lock(&tlbivax_lock);
_tlbivax_bcast(vmaddr, pid);
if (lock)
spin_unlock(&tlbivax_lock);
goto bail;
} else {
struct tlb_flush_param p = { .pid = pid, .addr = vmaddr };
smp_call_function_mask(cpu_mask,
do_flush_tlb_page_ipi, &p, 1);
}
}
_tlbil_va(vmaddr, pid);
bail:
preempt_enable();
}
EXPORT_SYMBOL(flush_tlb_page);
#endif /* CONFIG_SMP */
/*
* Flush kernel TLB entries in the given range
*/
void flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
#ifdef CONFIG_SMP
preempt_disable();
smp_call_function(do_flush_tlb_mm_ipi, NULL, 1);
_tlbil_pid(0);
preempt_enable();
#endif
_tlbil_pid(0);
}
EXPORT_SYMBOL(flush_tlb_kernel_range);
/*
* Currently, for range flushing, we just do a full mm flush. This should
* be optimized based on a threshold on the size of the range, since
* some implementation can stack multiple tlbivax before a tlbsync but
* for now, we keep it that way
*/
void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
flush_tlb_mm(vma->vm_mm);
}
EXPORT_SYMBOL(flush_tlb_range);
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