freebsd-skq/sys/i386/include/counter.h
Gleb Smirnoff 83c9dea1ba - Remove 'struct vmmeter' from 'struct pcpu', leaving only global vmmeter
in place.  To do per-cpu stats, convert all fields that previously were
  maintained in the vmmeters that sit in pcpus to counter(9).
- Since some vmmeter stats may be touched at very early stages of boot,
  before we have set up UMA and we can do counter_u64_alloc(), provide an
  early counter mechanism:
  o Leave one spare uint64_t in struct pcpu, named pc_early_dummy_counter.
  o Point counter(9) fields of vmmeter to pcpu[0].pc_early_dummy_counter,
    so that at early stages of boot, before counters are allocated we already
    point to a counter that can be safely written to.
  o For sparc64 that required a whole dummy pcpu[MAXCPU] array.

Further related changes:
- Don't include vmmeter.h into pcpu.h.
- vm.stats.vm.v_swappgsout and vm.stats.vm.v_swappgsin changed to 64-bit,
  to match kernel representation.
- struct vmmeter hidden under _KERNEL, and only vmstat(1) is an exclusion.

This is based on benno@'s 4-year old patch:
https://lists.freebsd.org/pipermail/freebsd-arch/2013-July/014471.html

Reviewed by:	kib, gallatin, marius, lidl
Differential Revision:	https://reviews.freebsd.org/D10156
2017-04-17 17:34:47 +00:00

181 lines
4.4 KiB
C

/*-
* Copyright (c) 2012 Konstantin Belousov <kib@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef __MACHINE_COUNTER_H__
#define __MACHINE_COUNTER_H__
#include <sys/pcpu.h>
#ifdef INVARIANTS
#include <sys/proc.h>
#endif
#include <machine/md_var.h>
#include <machine/specialreg.h>
extern struct pcpu __pcpu[];
#define EARLY_COUNTER &__pcpu[0].pc_early_dummy_counter
#define counter_enter() do { \
if ((cpu_feature & CPUID_CX8) == 0) \
critical_enter(); \
} while (0)
#define counter_exit() do { \
if ((cpu_feature & CPUID_CX8) == 0) \
critical_exit(); \
} while (0)
static inline void
counter_64_inc_8b(uint64_t *p, int64_t inc)
{
__asm __volatile(
"movl %%fs:(%%esi),%%eax\n\t"
"movl %%fs:4(%%esi),%%edx\n"
"1:\n\t"
"movl %%eax,%%ebx\n\t"
"movl %%edx,%%ecx\n\t"
"addl (%%edi),%%ebx\n\t"
"adcl 4(%%edi),%%ecx\n\t"
"cmpxchg8b %%fs:(%%esi)\n\t"
"jnz 1b"
:
: "S" ((char *)p - (char *)&__pcpu[0]), "D" (&inc)
: "memory", "cc", "eax", "edx", "ebx", "ecx");
}
#ifdef IN_SUBR_COUNTER_C
static inline uint64_t
counter_u64_read_one_8b(uint64_t *p)
{
uint32_t res_lo, res_high;
__asm __volatile(
"movl %%eax,%%ebx\n\t"
"movl %%edx,%%ecx\n\t"
"cmpxchg8b (%2)"
: "=a" (res_lo), "=d"(res_high)
: "SD" (p)
: "cc", "ebx", "ecx");
return (res_lo + ((uint64_t)res_high << 32));
}
static inline uint64_t
counter_u64_fetch_inline(uint64_t *p)
{
uint64_t res;
int i;
res = 0;
if ((cpu_feature & CPUID_CX8) == 0) {
/*
* The machines without cmpxchg8b are not SMP.
* Disabling the preemption provides atomicity of the
* counter reading, since update is done in the
* critical section as well.
*/
critical_enter();
CPU_FOREACH(i) {
res += *(uint64_t *)((char *)p +
sizeof(struct pcpu) * i);
}
critical_exit();
} else {
CPU_FOREACH(i)
res += counter_u64_read_one_8b((uint64_t *)((char *)p +
sizeof(struct pcpu) * i));
}
return (res);
}
static inline void
counter_u64_zero_one_8b(uint64_t *p)
{
__asm __volatile(
"movl (%0),%%eax\n\t"
"movl 4(%0),%%edx\n"
"xorl %%ebx,%%ebx\n\t"
"xorl %%ecx,%%ecx\n\t"
"1:\n\t"
"cmpxchg8b (%0)\n\t"
"jnz 1b"
:
: "SD" (p)
: "memory", "cc", "eax", "edx", "ebx", "ecx");
}
static void
counter_u64_zero_one_cpu(void *arg)
{
uint64_t *p;
p = (uint64_t *)((char *)arg + sizeof(struct pcpu) * PCPU_GET(cpuid));
counter_u64_zero_one_8b(p);
}
static inline void
counter_u64_zero_inline(counter_u64_t c)
{
int i;
if ((cpu_feature & CPUID_CX8) == 0) {
critical_enter();
CPU_FOREACH(i)
*(uint64_t *)((char *)c + sizeof(struct pcpu) * i) = 0;
critical_exit();
} else {
smp_rendezvous(smp_no_rendezvous_barrier,
counter_u64_zero_one_cpu, smp_no_rendezvous_barrier, c);
}
}
#endif
#define counter_u64_add_protected(c, inc) do { \
if ((cpu_feature & CPUID_CX8) == 0) { \
CRITICAL_ASSERT(curthread); \
*(uint64_t *)zpcpu_get(c) += (inc); \
} else \
counter_64_inc_8b((c), (inc)); \
} while (0)
static inline void
counter_u64_add(counter_u64_t c, int64_t inc)
{
if ((cpu_feature & CPUID_CX8) == 0) {
critical_enter();
*(uint64_t *)zpcpu_get(c) += inc;
critical_exit();
} else {
counter_64_inc_8b(c, inc);
}
}
#endif /* ! __MACHINE_COUNTER_H__ */