/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2017, Jeffrey Roberson <jeff@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 unmodified, 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 ``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 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.
*
*/
#include <sys/cdefs.h>
#include "opt_vm.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bitset.h>
#include <sys/domainset.h>
#include <sys/proc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/malloc.h>
#include <sys/rwlock.h>
#include <sys/vmmeter.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_domainset.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_phys.h>
#ifdef NUMA
/*
* Iterators are written such that the first nowait pass has as short a
* codepath as possible to eliminate bloat from the allocator. It is
* assumed that most allocations are successful.
*/
static int vm_domainset_default_stride = 64;
/*
* Determine which policy is to be used for this allocation.
*/
static void
vm_domainset_iter_init(struct vm_domainset_iter *di, struct domainset *ds,
int *iter, struct vm_object *obj, vm_pindex_t pindex)
{
di->di_domain = ds;
di->di_iter = iter;
di->di_policy = ds->ds_policy;
DOMAINSET_COPY(&ds->ds_mask, &di->di_valid_mask);
if (di->di_policy == DOMAINSET_POLICY_INTERLEAVE) {
#if VM_NRESERVLEVEL > 0
if (vm_object_reserv(obj)) {
/*
* Color the pindex so we end up on the correct
* reservation boundary.
*/
pindex += obj->pg_color;
pindex >>= VM_LEVEL_0_ORDER;
} else
#endif
pindex /= vm_domainset_default_stride;
/*
* Offset pindex so the first page of each object does
* not end up in domain 0.
*/
if (obj != NULL)
pindex += (((uintptr_t)obj) / sizeof(*obj));
di->di_offset = pindex;
}
/* Skip domains below min on the first pass. */
di->di_minskip = true;
}
static void
vm_domainset_iter_rr(struct vm_domainset_iter *di, int *domain)
{
*domain = di->di_domain->ds_order[
++(*di->di_iter) % di->di_domain->ds_cnt];
}
static void
vm_domainset_iter_prefer(struct vm_domainset_iter *di, int *domain)
{
int d;
do {
d = di->di_domain->ds_order[
++(*di->di_iter) % di->di_domain->ds_cnt];
} while (d == di->di_domain->ds_prefer);
*domain = d;
}
static void
vm_domainset_iter_interleave(struct vm_domainset_iter *di, int *domain)
{
int d;
d = di->di_offset % di->di_domain->ds_cnt;
*di->di_iter = d;
*domain = di->di_domain->ds_order[d];
}
static void
vm_domainset_iter_next(struct vm_domainset_iter *di, int *domain)
{
KASSERT(di->di_n > 0,
("vm_domainset_iter_first: Invalid n %d", di->di_n));
switch (di->di_policy) {
case DOMAINSET_POLICY_FIRSTTOUCH:
/*
* To prevent impossible allocations we convert an invalid
* first-touch to round-robin.
*/
/* FALLTHROUGH */
case DOMAINSET_POLICY_INTERLEAVE:
/* FALLTHROUGH */
case DOMAINSET_POLICY_ROUNDROBIN:
vm_domainset_iter_rr(di, domain);
break;
case DOMAINSET_POLICY_PREFER:
vm_domainset_iter_prefer(di, domain);
break;
default:
panic("vm_domainset_iter_first: Unknown policy %d",
di->di_policy);
}
KASSERT(*domain < vm_ndomains,
("vm_domainset_iter_next: Invalid domain %d", *domain));
}
static void
vm_domainset_iter_first(struct vm_domainset_iter *di, int *domain)
{
switch (di->di_policy) {
case DOMAINSET_POLICY_FIRSTTOUCH:
*domain = PCPU_GET(domain);
if (DOMAINSET_ISSET(*domain, &di->di_valid_mask)) {
/*
* Add an extra iteration because we will visit the
* current domain a second time in the rr iterator.
*/
di->di_n = di->di_domain->ds_cnt + 1;
break;
}
/*
* To prevent impossible allocations we convert an invalid
* first-touch to round-robin.
*/
/* FALLTHROUGH */
case DOMAINSET_POLICY_ROUNDROBIN:
di->di_n = di->di_domain->ds_cnt;
vm_domainset_iter_rr(di, domain);
break;
case DOMAINSET_POLICY_PREFER:
*domain = di->di_domain->ds_prefer;
di->di_n = di->di_domain->ds_cnt;
break;
case DOMAINSET_POLICY_INTERLEAVE:
vm_domainset_iter_interleave(di, domain);
di->di_n = di->di_domain->ds_cnt;
break;
default:
panic("vm_domainset_iter_first: Unknown policy %d",
di->di_policy);
}
KASSERT(di->di_n > 0,
("vm_domainset_iter_first: Invalid n %d", di->di_n));
KASSERT(*domain < vm_ndomains,
("vm_domainset_iter_first: Invalid domain %d", *domain));
}
void
vm_domainset_iter_page_init(struct vm_domainset_iter *di, struct vm_object *obj,
vm_pindex_t pindex, int *domain, int *req)
{
struct domainset_ref *dr;
/*
* Object policy takes precedence over thread policy. The policies
* are immutable and unsynchronized. Updates can race but pointer
* loads are assumed to be atomic.
*/
if (obj != NULL && obj->domain.dr_policy != NULL)
dr = &obj->domain;
else
dr = &curthread->td_domain;
vm_domainset_iter_init(di, dr->dr_policy, &dr->dr_iter, obj, pindex);
di->di_flags = *req;
*req = (di->di_flags & ~(VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL)) |
VM_ALLOC_NOWAIT;
vm_domainset_iter_first(di, domain);
if (vm_page_count_min_domain(*domain))
vm_domainset_iter_page(di, obj, domain);
}
int
vm_domainset_iter_page(struct vm_domainset_iter *di, struct vm_object *obj,
int *domain)
{
if (__predict_false(DOMAINSET_EMPTY(&di->di_valid_mask)))
return (ENOMEM);
/* If there are more domains to visit we run the iterator. */
while (--di->di_n != 0) {
vm_domainset_iter_next(di, domain);
if (DOMAINSET_ISSET(*domain, &di->di_valid_mask) &&
(!di->di_minskip || !vm_page_count_min_domain(*domain)))
return (0);
}
/* If we skipped domains below min restart the search. */
if (di->di_minskip) {
di->di_minskip = false;
vm_domainset_iter_first(di, domain);
return (0);
}
/* If we visited all domains and this was a NOWAIT we return error. */
if ((di->di_flags & (VM_ALLOC_WAITOK | VM_ALLOC_WAITFAIL)) == 0)
return (ENOMEM);
/* Wait for one of the domains to accumulate some free pages. */
if (obj != NULL)
VM_OBJECT_WUNLOCK(obj);
vm_wait_doms(&di->di_valid_mask, 0);
if (obj != NULL)
VM_OBJECT_WLOCK(obj);
if ((di->di_flags & VM_ALLOC_WAITFAIL) != 0)
return (ENOMEM);
/* Restart the search. */
vm_domainset_iter_first(di, domain);
return (0);
}
static void
_vm_domainset_iter_policy_init(struct vm_domainset_iter *di, int *domain,
int *flags)
{
di->di_flags = *flags;
*flags = (di->di_flags & ~M_WAITOK) | M_NOWAIT;
vm_domainset_iter_first(di, domain);
if (vm_page_count_min_domain(*domain))
vm_domainset_iter_policy(di, domain);
}
void
vm_domainset_iter_policy_init(struct vm_domainset_iter *di,
struct domainset *ds, int *domain, int *flags)
{
vm_domainset_iter_init(di, ds, &curthread->td_domain.dr_iter, NULL, 0);
_vm_domainset_iter_policy_init(di, domain, flags);
}
void
vm_domainset_iter_policy_ref_init(struct vm_domainset_iter *di,
struct domainset_ref *dr, int *domain, int *flags)
{
vm_domainset_iter_init(di, dr->dr_policy, &dr->dr_iter, NULL, 0);
_vm_domainset_iter_policy_init(di, domain, flags);
}
int
vm_domainset_iter_policy(struct vm_domainset_iter *di, int *domain)
{
if (DOMAINSET_EMPTY(&di->di_valid_mask))
return (ENOMEM);
/* If there are more domains to visit we run the iterator. */
while (--di->di_n != 0) {
vm_domainset_iter_next(di, domain);
if (DOMAINSET_ISSET(*domain, &di->di_valid_mask) &&
(!di->di_minskip || !vm_page_count_min_domain(*domain)))
return (0);
}
/* If we skipped domains below min restart the search. */
if (di->di_minskip) {
di->di_minskip = false;
vm_domainset_iter_first(di, domain);
return (0);
}
/* If we visited all domains and this was a NOWAIT we return error. */
if ((di->di_flags & M_WAITOK) == 0)
return (ENOMEM);
/* Wait for one of the domains to accumulate some free pages. */
vm_wait_doms(&di->di_valid_mask, 0);
/* Restart the search. */
vm_domainset_iter_first(di, domain);
return (0);
}
void
vm_domainset_iter_ignore(struct vm_domainset_iter *di, int domain)
{
KASSERT(DOMAINSET_ISSET(domain, &di->di_valid_mask),
("%s: domain %d not present in di_valid_mask for di %p",
__func__, domain, di));
DOMAINSET_CLR(domain, &di->di_valid_mask);
}
#else /* !NUMA */
int
vm_domainset_iter_page(struct vm_domainset_iter *di, struct vm_object *obj,
int *domain)
{
return (EJUSTRETURN);
}
void
vm_domainset_iter_page_init(struct vm_domainset_iter *di, struct vm_object *obj,
vm_pindex_t pindex, int *domain, int *flags)
{
*domain = 0;
}
int
vm_domainset_iter_policy(struct vm_domainset_iter *di, int *domain)
{
return (EJUSTRETURN);
}
void
vm_domainset_iter_policy_init(struct vm_domainset_iter *di,
struct domainset *ds, int *domain, int *flags)
{
*domain = 0;
}
void
vm_domainset_iter_policy_ref_init(struct vm_domainset_iter *di,
struct domainset_ref *dr, int *domain, int *flags)
{
*domain = 0;
}
void
vm_domainset_iter_ignore(struct vm_domainset_iter *di __unused,
int domain __unused)
{
}
#endif /* NUMA */
