nagai/kernel
3
0
Fork 0
forked from mirrors/linux
Code Pull requests Activity

x86/hyper-v: Support extended CPU ranges for TLB flush hypercalls

Browse source 
Hyper-V hosts may support more than 64 vCPUs, we need to use
HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX/LIST_EX hypercalls in this
case.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devel@linuxdriverproject.org
Link: http://lkml.kernel.org/r/20170802160921.21791-9-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Vitaly Kuznetsov 2017-08-02 18:09:20 +02:00 committed by Ingo Molnar
parent 3e83dfd5d8
commit 628f54cc64
2 changed files with 140 additions and 3 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

133
arch/x86/hyperv/mmu.c
View file

@ -18,11 +18,25 @@ struct hv_flush_pcpu {
u64 gva_list[];
};
/* HvFlushVirtualAddressSpaceEx, HvFlushVirtualAddressListEx hypercalls */
struct hv_flush_pcpu_ex {
u64 address_space;
u64 flags;
struct {
u64 format;
u64 valid_bank_mask;
u64 bank_contents[];
} hv_vp_set;
u64 gva_list[];
};
/* Each gva in gva_list encodes up to 4096 pages to flush */
#define HV_TLB_FLUSH_UNIT (4096 * PAGE_SIZE)
static struct hv_flush_pcpu __percpu *pcpu_flush;
static struct hv_flush_pcpu_ex __percpu *pcpu_flush_ex;
/*
* Fills in gva_list starting from offset. Returns the number of items added.
*/
@ -53,6 +67,34 @@ static inline int fill_gva_list(u64 gva_list[], int offset,
return gva_n - offset;
}
/* Return the number of banks in the resulting vp_set */
static inline int cpumask_to_vp_set(struct hv_flush_pcpu_ex *flush,
const struct cpumask *cpus)
{
int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
/*
* Some banks may end up being empty but this is acceptable.
*/
for_each_cpu(cpu, cpus) {
vcpu = hv_cpu_number_to_vp_number(cpu);
vcpu_bank = vcpu / 64;
vcpu_offset = vcpu % 64;
/* valid_bank_mask can represent up to 64 banks */
if (vcpu_bank >= 64)
return 0;
__set_bit(vcpu_offset, (unsigned long *)
&flush->hv_vp_set.bank_contents[vcpu_bank]);
if (vcpu_bank >= nr_bank)
nr_bank = vcpu_bank + 1;
}
flush->hv_vp_set.valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
return nr_bank;
}
static void hyperv_flush_tlb_others(const struct cpumask *cpus,
const struct flush_tlb_info *info)
{
@ -122,17 +164,102 @@ static void hyperv_flush_tlb_others(const struct cpumask *cpus,
native_flush_tlb_others(cpus, info);
}
static void hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
const struct flush_tlb_info *info)
{
int nr_bank = 0, max_gvas, gva_n;
struct hv_flush_pcpu_ex *flush;
u64 status = U64_MAX;
unsigned long flags;
if (!pcpu_flush_ex || !hv_hypercall_pg)
goto do_native;
if (cpumask_empty(cpus))
return;
local_irq_save(flags);
flush = this_cpu_ptr(pcpu_flush_ex);
if (info->mm) {
flush->address_space = virt_to_phys(info->mm->pgd);
flush->flags = 0;
} else {
flush->address_space = 0;
flush->flags = HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES;
}
flush->hv_vp_set.valid_bank_mask = 0;
if (!cpumask_equal(cpus, cpu_present_mask)) {
flush->hv_vp_set.format = HV_GENERIC_SET_SPARCE_4K;
nr_bank = cpumask_to_vp_set(flush, cpus);
}
if (!nr_bank) {
flush->hv_vp_set.format = HV_GENERIC_SET_ALL;
flush->flags |= HV_FLUSH_ALL_PROCESSORS;
}
/*
* We can flush not more than max_gvas with one hypercall. Flush the
* whole address space if we were asked to do more.
*/
max_gvas =
(PAGE_SIZE - sizeof(*flush) - nr_bank *
sizeof(flush->hv_vp_set.bank_contents[0])) /
sizeof(flush->gva_list[0]);
if (info->end == TLB_FLUSH_ALL) {
flush->flags |= HV_FLUSH_NON_GLOBAL_MAPPINGS_ONLY;
status = hv_do_rep_hypercall(
HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX,
0, nr_bank + 2, flush, NULL);
} else if (info->end &&
((info->end - info->start)/HV_TLB_FLUSH_UNIT) > max_gvas) {
status = hv_do_rep_hypercall(
HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX,
0, nr_bank + 2, flush, NULL);
} else {
gva_n = fill_gva_list(flush->gva_list, nr_bank,
info->start, info->end);
status = hv_do_rep_hypercall(
HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX,
gva_n, nr_bank + 2, flush, NULL);
}
local_irq_restore(flags);
if (!(status & HV_HYPERCALL_RESULT_MASK))
return;
do_native:
native_flush_tlb_others(cpus, info);
}
void hyperv_setup_mmu_ops(void)
{
if (ms_hyperv.hints & HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED) {
if (!(ms_hyperv.hints & HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED))
return;
setup_clear_cpu_cap(X86_FEATURE_PCID);
if (!(ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED)) {
pr_info("Using hypercall for remote TLB flush\n");
pv_mmu_ops.flush_tlb_others = hyperv_flush_tlb_others;
setup_clear_cpu_cap(X86_FEATURE_PCID);
} else {
pr_info("Using ext hypercall for remote TLB flush\n");
pv_mmu_ops.flush_tlb_others = hyperv_flush_tlb_others_ex;
}
}
void hyper_alloc_mmu(void)
{
if (ms_hyperv.hints & HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED)
if (!(ms_hyperv.hints & HV_X64_REMOTE_TLB_FLUSH_RECOMMENDED))
return;
if (!(ms_hyperv.hints & HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED))
pcpu_flush = __alloc_percpu(PAGE_SIZE, PAGE_SIZE);
else
pcpu_flush_ex = __alloc_percpu(PAGE_SIZE, PAGE_SIZE);
}

10
arch/x86/include/uapi/asm/hyperv.h
View file

@ -149,6 +149,9 @@
*/
#define HV_X64_DEPRECATING_AEOI_RECOMMENDED (1 << 9)
/* Recommend using the newer ExProcessorMasks interface */
#define HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED (1 << 11)
/*
* HV_VP_SET available
*/
@ -245,6 +248,8 @@
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE 0x0002
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST 0x0003
#define HVCALL_NOTIFY_LONG_SPIN_WAIT 0x0008
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX 0x0013
#define HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX 0x0014
#define HVCALL_POST_MESSAGE 0x005c
#define HVCALL_SIGNAL_EVENT 0x005d
@ -266,6 +271,11 @@
#define HV_FLUSH_NON_GLOBAL_MAPPINGS_ONLY BIT(2)
#define HV_FLUSH_USE_EXTENDED_RANGE_FORMAT BIT(3)
enum HV_GENERIC_SET_FORMAT {
HV_GENERIC_SET_SPARCE_4K,
HV_GENERIC_SET_ALL,
};
/* hypercall status code */
#define HV_STATUS_SUCCESS 0
#define HV_STATUS_INVALID_HYPERCALL_CODE 2