swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: 0c8efd610b58cb23cefdfa12015799079aef94ae authored by Linus Torvalds on 12 March 2018, 00:25:09 UTC
Linux 4.16-rc5
Linux 4.16-rc5
Tip revision: 0c8efd6
tlb-radix.c
/*
* TLB flush routines for radix kernels.
*
* Copyright 2015-2016, Aneesh Kumar K.V, IBM Corporation.
*
* 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/mm.h>
#include <linux/hugetlb.h>
#include <linux/memblock.h>
#include <asm/ppc-opcode.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
#include <asm/trace.h>
#include <asm/cputhreads.h>
#define RIC_FLUSH_TLB 0
#define RIC_FLUSH_PWC 1
#define RIC_FLUSH_ALL 2
/*
* tlbiel instruction for radix, set invalidation
* i.e., r=1 and is=01 or is=10 or is=11
*/
static inline void tlbiel_radix_set_isa300(unsigned int set, unsigned int is,
unsigned int pid,
unsigned int ric, unsigned int prs)
{
unsigned long rb;
unsigned long rs;
unsigned int r = 1; /* radix format */
rb = (set << PPC_BITLSHIFT(51)) | (is << PPC_BITLSHIFT(53));
rs = ((unsigned long)pid << PPC_BITLSHIFT(31));
asm volatile(PPC_TLBIEL(%0, %1, %2, %3, %4)
: : "r"(rb), "r"(rs), "i"(ric), "i"(prs), "r"(r)
: "memory");
}
static void tlbiel_all_isa300(unsigned int num_sets, unsigned int is)
{
unsigned int set;
asm volatile("ptesync": : :"memory");
/*
* Flush the first set of the TLB, and the entire Page Walk Cache
* and partition table entries. Then flush the remaining sets of the
* TLB.
*/
tlbiel_radix_set_isa300(0, is, 0, RIC_FLUSH_ALL, 0);
for (set = 1; set < num_sets; set++)
tlbiel_radix_set_isa300(set, is, 0, RIC_FLUSH_TLB, 0);
/* Do the same for process scoped entries. */
tlbiel_radix_set_isa300(0, is, 0, RIC_FLUSH_ALL, 1);
for (set = 1; set < num_sets; set++)
tlbiel_radix_set_isa300(set, is, 0, RIC_FLUSH_TLB, 1);
asm volatile("ptesync": : :"memory");
}
void radix__tlbiel_all(unsigned int action)
{
unsigned int is;
switch (action) {
case TLB_INVAL_SCOPE_GLOBAL:
is = 3;
break;
case TLB_INVAL_SCOPE_LPID:
is = 2;
break;
default:
BUG();
}
if (early_cpu_has_feature(CPU_FTR_ARCH_300))
tlbiel_all_isa300(POWER9_TLB_SETS_RADIX, is);
else
WARN(1, "%s called on pre-POWER9 CPU\n", __func__);
asm volatile(PPC_INVALIDATE_ERAT "; isync" : : :"memory");
}
static inline void __tlbiel_pid(unsigned long pid, int set,
unsigned long ric)
{
unsigned long rb,rs,prs,r;
rb = PPC_BIT(53); /* IS = 1 */
rb |= set << PPC_BITLSHIFT(51);
rs = ((unsigned long)pid) << PPC_BITLSHIFT(31);
prs = 1; /* process scoped */
r = 1; /* raidx format */
asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
trace_tlbie(0, 1, rb, rs, ric, prs, r);
}
static inline void __tlbie_pid(unsigned long pid, unsigned long ric)
{
unsigned long rb,rs,prs,r;
rb = PPC_BIT(53); /* IS = 1 */
rs = pid << PPC_BITLSHIFT(31);
prs = 1; /* process scoped */
r = 1; /* raidx format */
asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
trace_tlbie(0, 0, rb, rs, ric, prs, r);
}
/*
* We use 128 set in radix mode and 256 set in hpt mode.
*/
static inline void _tlbiel_pid(unsigned long pid, unsigned long ric)
{
int set;
asm volatile("ptesync": : :"memory");
/*
* Flush the first set of the TLB, and if we're doing a RIC_FLUSH_ALL,
* also flush the entire Page Walk Cache.
*/
__tlbiel_pid(pid, 0, ric);
/* For PWC, only one flush is needed */
if (ric == RIC_FLUSH_PWC) {
asm volatile("ptesync": : :"memory");
return;
}
/* For the remaining sets, just flush the TLB */
for (set = 1; set < POWER9_TLB_SETS_RADIX ; set++)
__tlbiel_pid(pid, set, RIC_FLUSH_TLB);
asm volatile("ptesync": : :"memory");
asm volatile(PPC_INVALIDATE_ERAT "; isync" : : :"memory");
}
static inline void _tlbie_pid(unsigned long pid, unsigned long ric)
{
asm volatile("ptesync": : :"memory");
__tlbie_pid(pid, ric);
asm volatile("eieio; tlbsync; ptesync": : :"memory");
}
static inline void __tlbiel_va(unsigned long va, unsigned long pid,
unsigned long ap, unsigned long ric)
{
unsigned long rb,rs,prs,r;
rb = va & ~(PPC_BITMASK(52, 63));
rb |= ap << PPC_BITLSHIFT(58);
rs = pid << PPC_BITLSHIFT(31);
prs = 1; /* process scoped */
r = 1; /* raidx format */
asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
trace_tlbie(0, 1, rb, rs, ric, prs, r);
}
static inline void __tlbiel_va_range(unsigned long start, unsigned long end,
unsigned long pid, unsigned long page_size,
unsigned long psize)
{
unsigned long addr;
unsigned long ap = mmu_get_ap(psize);
for (addr = start; addr < end; addr += page_size)
__tlbiel_va(addr, pid, ap, RIC_FLUSH_TLB);
}
static inline void _tlbiel_va(unsigned long va, unsigned long pid,
unsigned long psize, unsigned long ric)
{
unsigned long ap = mmu_get_ap(psize);
asm volatile("ptesync": : :"memory");
__tlbiel_va(va, pid, ap, ric);
asm volatile("ptesync": : :"memory");
}
static inline void _tlbiel_va_range(unsigned long start, unsigned long end,
unsigned long pid, unsigned long page_size,
unsigned long psize, bool also_pwc)
{
asm volatile("ptesync": : :"memory");
if (also_pwc)
__tlbiel_pid(pid, 0, RIC_FLUSH_PWC);
__tlbiel_va_range(start, end, pid, page_size, psize);
asm volatile("ptesync": : :"memory");
}
static inline void __tlbie_va(unsigned long va, unsigned long pid,
unsigned long ap, unsigned long ric)
{
unsigned long rb,rs,prs,r;
rb = va & ~(PPC_BITMASK(52, 63));
rb |= ap << PPC_BITLSHIFT(58);
rs = pid << PPC_BITLSHIFT(31);
prs = 1; /* process scoped */
r = 1; /* raidx format */
asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
trace_tlbie(0, 0, rb, rs, ric, prs, r);
}
static inline void __tlbie_va_range(unsigned long start, unsigned long end,
unsigned long pid, unsigned long page_size,
unsigned long psize)
{
unsigned long addr;
unsigned long ap = mmu_get_ap(psize);
for (addr = start; addr < end; addr += page_size)
__tlbie_va(addr, pid, ap, RIC_FLUSH_TLB);
}
static inline void _tlbie_va(unsigned long va, unsigned long pid,
unsigned long psize, unsigned long ric)
{
unsigned long ap = mmu_get_ap(psize);
asm volatile("ptesync": : :"memory");
__tlbie_va(va, pid, ap, ric);
asm volatile("eieio; tlbsync; ptesync": : :"memory");
}
static inline void _tlbie_va_range(unsigned long start, unsigned long end,
unsigned long pid, unsigned long page_size,
unsigned long psize, bool also_pwc)
{
asm volatile("ptesync": : :"memory");
if (also_pwc)
__tlbie_pid(pid, RIC_FLUSH_PWC);
__tlbie_va_range(start, end, pid, page_size, psize);
asm volatile("eieio; tlbsync; ptesync": : :"memory");
}
/*
* 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
*/
void radix__local_flush_tlb_mm(struct mm_struct *mm)
{
unsigned long pid;
preempt_disable();
pid = mm->context.id;
if (pid != MMU_NO_CONTEXT)
_tlbiel_pid(pid, RIC_FLUSH_TLB);
preempt_enable();
}
EXPORT_SYMBOL(radix__local_flush_tlb_mm);
#ifndef CONFIG_SMP
void radix__local_flush_all_mm(struct mm_struct *mm)
{
unsigned long pid;
preempt_disable();
pid = mm->context.id;
if (pid != MMU_NO_CONTEXT)
_tlbiel_pid(pid, RIC_FLUSH_ALL);
preempt_enable();
}
EXPORT_SYMBOL(radix__local_flush_all_mm);
#endif /* CONFIG_SMP */
void radix__local_flush_tlb_page_psize(struct mm_struct *mm, unsigned long vmaddr,
int psize)
{
unsigned long pid;
preempt_disable();
pid = mm->context.id;
if (pid != MMU_NO_CONTEXT)
_tlbiel_va(vmaddr, pid, psize, RIC_FLUSH_TLB);
preempt_enable();
}
void radix__local_flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
{
#ifdef CONFIG_HUGETLB_PAGE
/* need the return fix for nohash.c */
if (is_vm_hugetlb_page(vma))
return radix__local_flush_hugetlb_page(vma, vmaddr);
#endif
radix__local_flush_tlb_page_psize(vma->vm_mm, vmaddr, mmu_virtual_psize);
}
EXPORT_SYMBOL(radix__local_flush_tlb_page);
#ifdef CONFIG_SMP
void radix__flush_tlb_mm(struct mm_struct *mm)
{
unsigned long pid;
pid = mm->context.id;
if (unlikely(pid == MMU_NO_CONTEXT))
return;
preempt_disable();
if (!mm_is_thread_local(mm))
_tlbie_pid(pid, RIC_FLUSH_TLB);
else
_tlbiel_pid(pid, RIC_FLUSH_TLB);
preempt_enable();
}
EXPORT_SYMBOL(radix__flush_tlb_mm);
void radix__flush_all_mm(struct mm_struct *mm)
{
unsigned long pid;
pid = mm->context.id;
if (unlikely(pid == MMU_NO_CONTEXT))
return;
preempt_disable();
if (!mm_is_thread_local(mm))
_tlbie_pid(pid, RIC_FLUSH_ALL);
else
_tlbiel_pid(pid, RIC_FLUSH_ALL);
preempt_enable();
}
EXPORT_SYMBOL(radix__flush_all_mm);
void radix__flush_tlb_pwc(struct mmu_gather *tlb, unsigned long addr)
{
tlb->need_flush_all = 1;
}
EXPORT_SYMBOL(radix__flush_tlb_pwc);
void radix__flush_tlb_page_psize(struct mm_struct *mm, unsigned long vmaddr,
int psize)
{
unsigned long pid;
pid = mm->context.id;
if (unlikely(pid == MMU_NO_CONTEXT))
return;
preempt_disable();
if (!mm_is_thread_local(mm))
_tlbie_va(vmaddr, pid, psize, RIC_FLUSH_TLB);
else
_tlbiel_va(vmaddr, pid, psize, RIC_FLUSH_TLB);
preempt_enable();
}
void radix__flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
{
#ifdef CONFIG_HUGETLB_PAGE
if (is_vm_hugetlb_page(vma))
return radix__flush_hugetlb_page(vma, vmaddr);
#endif
radix__flush_tlb_page_psize(vma->vm_mm, vmaddr, mmu_virtual_psize);
}
EXPORT_SYMBOL(radix__flush_tlb_page);
#else /* CONFIG_SMP */
#define radix__flush_all_mm radix__local_flush_all_mm
#endif /* CONFIG_SMP */
void radix__flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
_tlbie_pid(0, RIC_FLUSH_ALL);
}
EXPORT_SYMBOL(radix__flush_tlb_kernel_range);
#define TLB_FLUSH_ALL -1UL
/*
* Number of pages above which we invalidate the entire PID rather than
* flush individual pages, for local and global flushes respectively.
*
* tlbie goes out to the interconnect and individual ops are more costly.
* It also does not iterate over sets like the local tlbiel variant when
* invalidating a full PID, so it has a far lower threshold to change from
* individual page flushes to full-pid flushes.
*/
static unsigned long tlb_single_page_flush_ceiling __read_mostly = 33;
static unsigned long tlb_local_single_page_flush_ceiling __read_mostly = POWER9_TLB_SETS_RADIX * 2;
void radix__flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
struct mm_struct *mm = vma->vm_mm;
unsigned long pid;
unsigned int page_shift = mmu_psize_defs[mmu_virtual_psize].shift;
unsigned long page_size = 1UL << page_shift;
unsigned long nr_pages = (end - start) >> page_shift;
bool local, full;
#ifdef CONFIG_HUGETLB_PAGE
if (is_vm_hugetlb_page(vma))
return radix__flush_hugetlb_tlb_range(vma, start, end);
#endif
pid = mm->context.id;
if (unlikely(pid == MMU_NO_CONTEXT))
return;
preempt_disable();
if (mm_is_thread_local(mm)) {
local = true;
full = (end == TLB_FLUSH_ALL ||
nr_pages > tlb_local_single_page_flush_ceiling);
} else {
local = false;
full = (end == TLB_FLUSH_ALL ||
nr_pages > tlb_single_page_flush_ceiling);
}
if (full) {
if (local)
_tlbiel_pid(pid, RIC_FLUSH_TLB);
else
_tlbie_pid(pid, RIC_FLUSH_TLB);
} else {
bool hflush = false;
unsigned long hstart, hend;
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
hstart = (start + HPAGE_PMD_SIZE - 1) >> HPAGE_PMD_SHIFT;
hend = end >> HPAGE_PMD_SHIFT;
if (hstart < hend) {
hstart <<= HPAGE_PMD_SHIFT;
hend <<= HPAGE_PMD_SHIFT;
hflush = true;
}
#endif
asm volatile("ptesync": : :"memory");
if (local) {
__tlbiel_va_range(start, end, pid, page_size, mmu_virtual_psize);
if (hflush)
__tlbiel_va_range(hstart, hend, pid,
HPAGE_PMD_SIZE, MMU_PAGE_2M);
asm volatile("ptesync": : :"memory");
} else {
__tlbie_va_range(start, end, pid, page_size, mmu_virtual_psize);
if (hflush)
__tlbie_va_range(hstart, hend, pid,
HPAGE_PMD_SIZE, MMU_PAGE_2M);
asm volatile("eieio; tlbsync; ptesync": : :"memory");
}
}
preempt_enable();
}
EXPORT_SYMBOL(radix__flush_tlb_range);
static int radix_get_mmu_psize(int page_size)
{
int psize;
if (page_size == (1UL << mmu_psize_defs[mmu_virtual_psize].shift))
psize = mmu_virtual_psize;
else if (page_size == (1UL << mmu_psize_defs[MMU_PAGE_2M].shift))
psize = MMU_PAGE_2M;
else if (page_size == (1UL << mmu_psize_defs[MMU_PAGE_1G].shift))
psize = MMU_PAGE_1G;
else
return -1;
return psize;
}
static void radix__flush_tlb_pwc_range_psize(struct mm_struct *mm, unsigned long start,
unsigned long end, int psize);
void radix__tlb_flush(struct mmu_gather *tlb)
{
int psize = 0;
struct mm_struct *mm = tlb->mm;
int page_size = tlb->page_size;
/*
* if page size is not something we understand, do a full mm flush
*
* A "fullmm" flush must always do a flush_all_mm (RIC=2) flush
* that flushes the process table entry cache upon process teardown.
* See the comment for radix in arch_exit_mmap().
*/
if (tlb->fullmm) {
radix__flush_all_mm(mm);
} else if ( (psize = radix_get_mmu_psize(page_size)) == -1) {
if (!tlb->need_flush_all)
radix__flush_tlb_mm(mm);
else
radix__flush_all_mm(mm);
} else {
unsigned long start = tlb->start;
unsigned long end = tlb->end;
if (!tlb->need_flush_all)
radix__flush_tlb_range_psize(mm, start, end, psize);
else
radix__flush_tlb_pwc_range_psize(mm, start, end, psize);
}
tlb->need_flush_all = 0;
}
static inline void __radix__flush_tlb_range_psize(struct mm_struct *mm,
unsigned long start, unsigned long end,
int psize, bool also_pwc)
{
unsigned long pid;
unsigned int page_shift = mmu_psize_defs[psize].shift;
unsigned long page_size = 1UL << page_shift;
unsigned long nr_pages = (end - start) >> page_shift;
bool local, full;
pid = mm->context.id;
if (unlikely(pid == MMU_NO_CONTEXT))
return;
preempt_disable();
if (mm_is_thread_local(mm)) {
local = true;
full = (end == TLB_FLUSH_ALL ||
nr_pages > tlb_local_single_page_flush_ceiling);
} else {
local = false;
full = (end == TLB_FLUSH_ALL ||
nr_pages > tlb_single_page_flush_ceiling);
}
if (full) {
if (local)
_tlbiel_pid(pid, also_pwc ? RIC_FLUSH_ALL : RIC_FLUSH_TLB);
else
_tlbie_pid(pid, also_pwc ? RIC_FLUSH_ALL: RIC_FLUSH_TLB);
} else {
if (local)
_tlbiel_va_range(start, end, pid, page_size, psize, also_pwc);
else
_tlbie_va_range(start, end, pid, page_size, psize, also_pwc);
}
preempt_enable();
}
void radix__flush_tlb_range_psize(struct mm_struct *mm, unsigned long start,
unsigned long end, int psize)
{
return __radix__flush_tlb_range_psize(mm, start, end, psize, false);
}
static void radix__flush_tlb_pwc_range_psize(struct mm_struct *mm, unsigned long start,
unsigned long end, int psize)
{
__radix__flush_tlb_range_psize(mm, start, end, psize, true);
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
void radix__flush_tlb_collapsed_pmd(struct mm_struct *mm, unsigned long addr)
{
unsigned long pid, end;
pid = mm->context.id;
if (unlikely(pid == MMU_NO_CONTEXT))
return;
/* 4k page size, just blow the world */
if (PAGE_SIZE == 0x1000) {
radix__flush_all_mm(mm);
return;
}
end = addr + HPAGE_PMD_SIZE;
/* Otherwise first do the PWC, then iterate the pages. */
preempt_disable();
if (mm_is_thread_local(mm)) {
_tlbiel_va_range(addr, end, pid, PAGE_SIZE, mmu_virtual_psize, true);
} else {
_tlbie_va_range(addr, end, pid, PAGE_SIZE, mmu_virtual_psize, true);
}
preempt_enable();
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
void radix__flush_tlb_lpid_va(unsigned long lpid, unsigned long gpa,
unsigned long page_size)
{
unsigned long rb,rs,prs,r;
unsigned long ap;
unsigned long ric = RIC_FLUSH_TLB;
ap = mmu_get_ap(radix_get_mmu_psize(page_size));
rb = gpa & ~(PPC_BITMASK(52, 63));
rb |= ap << PPC_BITLSHIFT(58);
rs = lpid & ((1UL << 32) - 1);
prs = 0; /* process scoped */
r = 1; /* raidx format */
asm volatile("ptesync": : :"memory");
asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
asm volatile("eieio; tlbsync; ptesync": : :"memory");
trace_tlbie(lpid, 0, rb, rs, ric, prs, r);
}
EXPORT_SYMBOL(radix__flush_tlb_lpid_va);
void radix__flush_tlb_lpid(unsigned long lpid)
{
unsigned long rb,rs,prs,r;
unsigned long ric = RIC_FLUSH_ALL;
rb = 0x2 << PPC_BITLSHIFT(53); /* IS = 2 */
rs = lpid & ((1UL << 32) - 1);
prs = 0; /* partition scoped */
r = 1; /* raidx format */
asm volatile("ptesync": : :"memory");
asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(rs) : "memory");
asm volatile("eieio; tlbsync; ptesync": : :"memory");
trace_tlbie(lpid, 0, rb, rs, ric, prs, r);
}
EXPORT_SYMBOL(radix__flush_tlb_lpid);
void radix__flush_pmd_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
radix__flush_tlb_range_psize(vma->vm_mm, start, end, MMU_PAGE_2M);
}
EXPORT_SYMBOL(radix__flush_pmd_tlb_range);
void radix__flush_tlb_all(void)
{
unsigned long rb,prs,r,rs;
unsigned long ric = RIC_FLUSH_ALL;
rb = 0x3 << PPC_BITLSHIFT(53); /* IS = 3 */
prs = 0; /* partition scoped */
r = 1; /* raidx format */
rs = 1 & ((1UL << 32) - 1); /* any LPID value to flush guest mappings */
asm volatile("ptesync": : :"memory");
/*
* now flush guest entries by passing PRS = 1 and LPID != 0
*/
asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
: : "r"(rb), "i"(r), "i"(1), "i"(ric), "r"(rs) : "memory");
/*
* now flush host entires by passing PRS = 0 and LPID == 0
*/
asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
: : "r"(rb), "i"(r), "i"(prs), "i"(ric), "r"(0) : "memory");
asm volatile("eieio; tlbsync; ptesync": : :"memory");
}
void radix__flush_tlb_pte_p9_dd1(unsigned long old_pte, struct mm_struct *mm,
unsigned long address)
{
/*
* We track page size in pte only for DD1, So we can
* call this only on DD1.
*/
if (!cpu_has_feature(CPU_FTR_POWER9_DD1)) {
VM_WARN_ON(1);
return;
}
if (old_pte & R_PAGE_LARGE)
radix__flush_tlb_page_psize(mm, address, MMU_PAGE_2M);
else
radix__flush_tlb_page_psize(mm, address, mmu_virtual_psize);
}
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
extern void radix_kvm_prefetch_workaround(struct mm_struct *mm)
{
unsigned int pid = mm->context.id;
if (unlikely(pid == MMU_NO_CONTEXT))
return;
/*
* If this context hasn't run on that CPU before and KVM is
* around, there's a slim chance that the guest on another
* CPU just brought in obsolete translation into the TLB of
* this CPU due to a bad prefetch using the guest PID on
* the way into the hypervisor.
*
* We work around this here. If KVM is possible, we check if
* any sibling thread is in KVM. If it is, the window may exist
* and thus we flush that PID from the core.
*
* A potential future improvement would be to mark which PIDs
* have never been used on the system and avoid it if the PID
* is new and the process has no other cpumask bit set.
*/
if (cpu_has_feature(CPU_FTR_HVMODE) && radix_enabled()) {
int cpu = smp_processor_id();
int sib = cpu_first_thread_sibling(cpu);
bool flush = false;
for (; sib <= cpu_last_thread_sibling(cpu) && !flush; sib++) {
if (sib == cpu)
continue;
if (paca[sib].kvm_hstate.kvm_vcpu)
flush = true;
}
if (flush)
_tlbiel_pid(pid, RIC_FLUSH_ALL);
}
}
EXPORT_SYMBOL_GPL(radix_kvm_prefetch_workaround);
#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */