f749b57e89
revision 255744. sys/kern/subr_smp.c: IPI_SUSPEND is only available on amd64 and i386. Protect new uses of this constant with #ifdefs to avoid impacting other platforms. Approved by: re (blanket Xen)
837 lines
21 KiB
C
837 lines
21 KiB
C
/*-
|
|
* Copyright (c) 2001, John Baldwin <jhb@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.
|
|
* 3. Neither the name of the author nor the names of any co-contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
/*
|
|
* This module holds the global variables and machine independent functions
|
|
* used for the kernel SMP support.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/ktr.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/bus.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/pcpu.h>
|
|
#include <sys/sched.h>
|
|
#include <sys/smp.h>
|
|
#include <sys/sysctl.h>
|
|
|
|
#include <machine/cpu.h>
|
|
#include <machine/smp.h>
|
|
|
|
#include "opt_sched.h"
|
|
|
|
#ifdef SMP
|
|
volatile cpuset_t stopped_cpus;
|
|
volatile cpuset_t started_cpus;
|
|
volatile cpuset_t suspended_cpus;
|
|
cpuset_t hlt_cpus_mask;
|
|
cpuset_t logical_cpus_mask;
|
|
|
|
void (*cpustop_restartfunc)(void);
|
|
#endif
|
|
/* This is used in modules that need to work in both SMP and UP. */
|
|
cpuset_t all_cpus;
|
|
|
|
int mp_ncpus;
|
|
/* export this for libkvm consumers. */
|
|
int mp_maxcpus = MAXCPU;
|
|
|
|
volatile int smp_started;
|
|
u_int mp_maxid;
|
|
|
|
static SYSCTL_NODE(_kern, OID_AUTO, smp, CTLFLAG_RD|CTLFLAG_CAPRD, NULL,
|
|
"Kernel SMP");
|
|
|
|
SYSCTL_INT(_kern_smp, OID_AUTO, maxid, CTLFLAG_RD|CTLFLAG_CAPRD, &mp_maxid, 0,
|
|
"Max CPU ID.");
|
|
|
|
SYSCTL_INT(_kern_smp, OID_AUTO, maxcpus, CTLFLAG_RD|CTLFLAG_CAPRD, &mp_maxcpus,
|
|
0, "Max number of CPUs that the system was compiled for.");
|
|
|
|
int smp_active = 0; /* are the APs allowed to run? */
|
|
SYSCTL_INT(_kern_smp, OID_AUTO, active, CTLFLAG_RW, &smp_active, 0,
|
|
"Number of Auxillary Processors (APs) that were successfully started");
|
|
|
|
int smp_disabled = 0; /* has smp been disabled? */
|
|
SYSCTL_INT(_kern_smp, OID_AUTO, disabled, CTLFLAG_RDTUN|CTLFLAG_CAPRD,
|
|
&smp_disabled, 0, "SMP has been disabled from the loader");
|
|
TUNABLE_INT("kern.smp.disabled", &smp_disabled);
|
|
|
|
int smp_cpus = 1; /* how many cpu's running */
|
|
SYSCTL_INT(_kern_smp, OID_AUTO, cpus, CTLFLAG_RD|CTLFLAG_CAPRD, &smp_cpus, 0,
|
|
"Number of CPUs online");
|
|
|
|
int smp_topology = 0; /* Which topology we're using. */
|
|
SYSCTL_INT(_kern_smp, OID_AUTO, topology, CTLFLAG_RD, &smp_topology, 0,
|
|
"Topology override setting; 0 is default provided by hardware.");
|
|
TUNABLE_INT("kern.smp.topology", &smp_topology);
|
|
|
|
#ifdef SMP
|
|
/* Enable forwarding of a signal to a process running on a different CPU */
|
|
static int forward_signal_enabled = 1;
|
|
SYSCTL_INT(_kern_smp, OID_AUTO, forward_signal_enabled, CTLFLAG_RW,
|
|
&forward_signal_enabled, 0,
|
|
"Forwarding of a signal to a process on a different CPU");
|
|
|
|
/* Variables needed for SMP rendezvous. */
|
|
static volatile int smp_rv_ncpus;
|
|
static void (*volatile smp_rv_setup_func)(void *arg);
|
|
static void (*volatile smp_rv_action_func)(void *arg);
|
|
static void (*volatile smp_rv_teardown_func)(void *arg);
|
|
static void *volatile smp_rv_func_arg;
|
|
static volatile int smp_rv_waiters[4];
|
|
|
|
/*
|
|
* Shared mutex to restrict busywaits between smp_rendezvous() and
|
|
* smp(_targeted)_tlb_shootdown(). A deadlock occurs if both of these
|
|
* functions trigger at once and cause multiple CPUs to busywait with
|
|
* interrupts disabled.
|
|
*/
|
|
struct mtx smp_ipi_mtx;
|
|
|
|
/*
|
|
* Let the MD SMP code initialize mp_maxid very early if it can.
|
|
*/
|
|
static void
|
|
mp_setmaxid(void *dummy)
|
|
{
|
|
cpu_mp_setmaxid();
|
|
}
|
|
SYSINIT(cpu_mp_setmaxid, SI_SUB_TUNABLES, SI_ORDER_FIRST, mp_setmaxid, NULL);
|
|
|
|
/*
|
|
* Call the MD SMP initialization code.
|
|
*/
|
|
static void
|
|
mp_start(void *dummy)
|
|
{
|
|
|
|
mtx_init(&smp_ipi_mtx, "smp rendezvous", NULL, MTX_SPIN);
|
|
|
|
/* Probe for MP hardware. */
|
|
if (smp_disabled != 0 || cpu_mp_probe() == 0) {
|
|
mp_ncpus = 1;
|
|
CPU_SETOF(PCPU_GET(cpuid), &all_cpus);
|
|
return;
|
|
}
|
|
|
|
cpu_mp_start();
|
|
printf("FreeBSD/SMP: Multiprocessor System Detected: %d CPUs\n",
|
|
mp_ncpus);
|
|
cpu_mp_announce();
|
|
}
|
|
SYSINIT(cpu_mp, SI_SUB_CPU, SI_ORDER_THIRD, mp_start, NULL);
|
|
|
|
void
|
|
forward_signal(struct thread *td)
|
|
{
|
|
int id;
|
|
|
|
/*
|
|
* signotify() has already set TDF_ASTPENDING and TDF_NEEDSIGCHECK on
|
|
* this thread, so all we need to do is poke it if it is currently
|
|
* executing so that it executes ast().
|
|
*/
|
|
THREAD_LOCK_ASSERT(td, MA_OWNED);
|
|
KASSERT(TD_IS_RUNNING(td),
|
|
("forward_signal: thread is not TDS_RUNNING"));
|
|
|
|
CTR1(KTR_SMP, "forward_signal(%p)", td->td_proc);
|
|
|
|
if (!smp_started || cold || panicstr)
|
|
return;
|
|
if (!forward_signal_enabled)
|
|
return;
|
|
|
|
/* No need to IPI ourself. */
|
|
if (td == curthread)
|
|
return;
|
|
|
|
id = td->td_oncpu;
|
|
if (id == NOCPU)
|
|
return;
|
|
ipi_cpu(id, IPI_AST);
|
|
}
|
|
|
|
/*
|
|
* When called the executing CPU will send an IPI to all other CPUs
|
|
* requesting that they halt execution.
|
|
*
|
|
* Usually (but not necessarily) called with 'other_cpus' as its arg.
|
|
*
|
|
* - Signals all CPUs in map to stop.
|
|
* - Waits for each to stop.
|
|
*
|
|
* Returns:
|
|
* -1: error
|
|
* 0: NA
|
|
* 1: ok
|
|
*
|
|
*/
|
|
static int
|
|
generic_stop_cpus(cpuset_t map, u_int type)
|
|
{
|
|
#ifdef KTR
|
|
char cpusetbuf[CPUSETBUFSIZ];
|
|
#endif
|
|
static volatile u_int stopping_cpu = NOCPU;
|
|
int i;
|
|
volatile cpuset_t *cpus;
|
|
|
|
KASSERT(
|
|
#if defined(__amd64__) || defined(__i386__)
|
|
type == IPI_STOP || type == IPI_STOP_HARD || type == IPI_SUSPEND,
|
|
#else
|
|
type == IPI_STOP || type == IPI_STOP_HARD,
|
|
#endif
|
|
("%s: invalid stop type", __func__));
|
|
|
|
if (!smp_started)
|
|
return (0);
|
|
|
|
CTR2(KTR_SMP, "stop_cpus(%s) with %u type",
|
|
cpusetobj_strprint(cpusetbuf, &map), type);
|
|
|
|
#if defined(__amd64__) || defined(__i386__)
|
|
/*
|
|
* When suspending, ensure there are are no IPIs in progress.
|
|
* IPIs that have been issued, but not yet delivered (e.g.
|
|
* not pending on a vCPU when running under virtualization)
|
|
* will be lost, violating FreeBSD's assumption of reliable
|
|
* IPI delivery.
|
|
*/
|
|
if (type == IPI_SUSPEND)
|
|
mtx_lock_spin(&smp_ipi_mtx);
|
|
#endif
|
|
|
|
if (stopping_cpu != PCPU_GET(cpuid))
|
|
while (atomic_cmpset_int(&stopping_cpu, NOCPU,
|
|
PCPU_GET(cpuid)) == 0)
|
|
while (stopping_cpu != NOCPU)
|
|
cpu_spinwait(); /* spin */
|
|
|
|
/* send the stop IPI to all CPUs in map */
|
|
ipi_selected(map, type);
|
|
|
|
#if defined(__amd64__) || defined(__i386__)
|
|
if (type == IPI_SUSPEND)
|
|
cpus = &suspended_cpus;
|
|
else
|
|
#endif
|
|
cpus = &stopped_cpus;
|
|
|
|
i = 0;
|
|
while (!CPU_SUBSET(cpus, &map)) {
|
|
/* spin */
|
|
cpu_spinwait();
|
|
i++;
|
|
if (i == 100000000) {
|
|
printf("timeout stopping cpus\n");
|
|
break;
|
|
}
|
|
}
|
|
|
|
#if defined(__amd64__) || defined(__i386__)
|
|
if (type == IPI_SUSPEND)
|
|
mtx_unlock_spin(&smp_ipi_mtx);
|
|
#endif
|
|
|
|
stopping_cpu = NOCPU;
|
|
return (1);
|
|
}
|
|
|
|
int
|
|
stop_cpus(cpuset_t map)
|
|
{
|
|
|
|
return (generic_stop_cpus(map, IPI_STOP));
|
|
}
|
|
|
|
int
|
|
stop_cpus_hard(cpuset_t map)
|
|
{
|
|
|
|
return (generic_stop_cpus(map, IPI_STOP_HARD));
|
|
}
|
|
|
|
#if defined(__amd64__) || defined(__i386__)
|
|
int
|
|
suspend_cpus(cpuset_t map)
|
|
{
|
|
|
|
return (generic_stop_cpus(map, IPI_SUSPEND));
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Called by a CPU to restart stopped CPUs.
|
|
*
|
|
* Usually (but not necessarily) called with 'stopped_cpus' as its arg.
|
|
*
|
|
* - Signals all CPUs in map to restart.
|
|
* - Waits for each to restart.
|
|
*
|
|
* Returns:
|
|
* -1: error
|
|
* 0: NA
|
|
* 1: ok
|
|
*/
|
|
static int
|
|
generic_restart_cpus(cpuset_t map, u_int type)
|
|
{
|
|
#ifdef KTR
|
|
char cpusetbuf[CPUSETBUFSIZ];
|
|
#endif
|
|
volatile cpuset_t *cpus;
|
|
|
|
KASSERT(
|
|
#if defined(__amd64__) || defined(__i386__)
|
|
type == IPI_STOP || type == IPI_STOP_HARD || type == IPI_SUSPEND,
|
|
#else
|
|
type == IPI_STOP || type == IPI_STOP_HARD,
|
|
#endif
|
|
("%s: invalid stop type", __func__));
|
|
|
|
if (!smp_started)
|
|
return 0;
|
|
|
|
CTR1(KTR_SMP, "restart_cpus(%s)", cpusetobj_strprint(cpusetbuf, &map));
|
|
|
|
#if defined(__amd64__) || defined(__i386__)
|
|
if (type == IPI_SUSPEND)
|
|
cpus = &suspended_cpus;
|
|
else
|
|
#endif
|
|
cpus = &stopped_cpus;
|
|
|
|
/* signal other cpus to restart */
|
|
CPU_COPY_STORE_REL(&map, &started_cpus);
|
|
|
|
/* wait for each to clear its bit */
|
|
while (CPU_OVERLAP(cpus, &map))
|
|
cpu_spinwait();
|
|
|
|
return 1;
|
|
}
|
|
|
|
int
|
|
restart_cpus(cpuset_t map)
|
|
{
|
|
|
|
return (generic_restart_cpus(map, IPI_STOP));
|
|
}
|
|
|
|
#if defined(__amd64__) || defined(__i386__)
|
|
int
|
|
resume_cpus(cpuset_t map)
|
|
{
|
|
|
|
return (generic_restart_cpus(map, IPI_SUSPEND));
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* All-CPU rendezvous. CPUs are signalled, all execute the setup function
|
|
* (if specified), rendezvous, execute the action function (if specified),
|
|
* rendezvous again, execute the teardown function (if specified), and then
|
|
* resume.
|
|
*
|
|
* Note that the supplied external functions _must_ be reentrant and aware
|
|
* that they are running in parallel and in an unknown lock context.
|
|
*/
|
|
void
|
|
smp_rendezvous_action(void)
|
|
{
|
|
struct thread *td;
|
|
void *local_func_arg;
|
|
void (*local_setup_func)(void*);
|
|
void (*local_action_func)(void*);
|
|
void (*local_teardown_func)(void*);
|
|
#ifdef INVARIANTS
|
|
int owepreempt;
|
|
#endif
|
|
|
|
/* Ensure we have up-to-date values. */
|
|
atomic_add_acq_int(&smp_rv_waiters[0], 1);
|
|
while (smp_rv_waiters[0] < smp_rv_ncpus)
|
|
cpu_spinwait();
|
|
|
|
/* Fetch rendezvous parameters after acquire barrier. */
|
|
local_func_arg = smp_rv_func_arg;
|
|
local_setup_func = smp_rv_setup_func;
|
|
local_action_func = smp_rv_action_func;
|
|
local_teardown_func = smp_rv_teardown_func;
|
|
|
|
/*
|
|
* Use a nested critical section to prevent any preemptions
|
|
* from occurring during a rendezvous action routine.
|
|
* Specifically, if a rendezvous handler is invoked via an IPI
|
|
* and the interrupted thread was in the critical_exit()
|
|
* function after setting td_critnest to 0 but before
|
|
* performing a deferred preemption, this routine can be
|
|
* invoked with td_critnest set to 0 and td_owepreempt true.
|
|
* In that case, a critical_exit() during the rendezvous
|
|
* action would trigger a preemption which is not permitted in
|
|
* a rendezvous action. To fix this, wrap all of the
|
|
* rendezvous action handlers in a critical section. We
|
|
* cannot use a regular critical section however as having
|
|
* critical_exit() preempt from this routine would also be
|
|
* problematic (the preemption must not occur before the IPI
|
|
* has been acknowledged via an EOI). Instead, we
|
|
* intentionally ignore td_owepreempt when leaving the
|
|
* critical section. This should be harmless because we do
|
|
* not permit rendezvous action routines to schedule threads,
|
|
* and thus td_owepreempt should never transition from 0 to 1
|
|
* during this routine.
|
|
*/
|
|
td = curthread;
|
|
td->td_critnest++;
|
|
#ifdef INVARIANTS
|
|
owepreempt = td->td_owepreempt;
|
|
#endif
|
|
|
|
/*
|
|
* If requested, run a setup function before the main action
|
|
* function. Ensure all CPUs have completed the setup
|
|
* function before moving on to the action function.
|
|
*/
|
|
if (local_setup_func != smp_no_rendevous_barrier) {
|
|
if (smp_rv_setup_func != NULL)
|
|
smp_rv_setup_func(smp_rv_func_arg);
|
|
atomic_add_int(&smp_rv_waiters[1], 1);
|
|
while (smp_rv_waiters[1] < smp_rv_ncpus)
|
|
cpu_spinwait();
|
|
}
|
|
|
|
if (local_action_func != NULL)
|
|
local_action_func(local_func_arg);
|
|
|
|
if (local_teardown_func != smp_no_rendevous_barrier) {
|
|
/*
|
|
* Signal that the main action has been completed. If a
|
|
* full exit rendezvous is requested, then all CPUs will
|
|
* wait here until all CPUs have finished the main action.
|
|
*/
|
|
atomic_add_int(&smp_rv_waiters[2], 1);
|
|
while (smp_rv_waiters[2] < smp_rv_ncpus)
|
|
cpu_spinwait();
|
|
|
|
if (local_teardown_func != NULL)
|
|
local_teardown_func(local_func_arg);
|
|
}
|
|
|
|
/*
|
|
* Signal that the rendezvous is fully completed by this CPU.
|
|
* This means that no member of smp_rv_* pseudo-structure will be
|
|
* accessed by this target CPU after this point; in particular,
|
|
* memory pointed by smp_rv_func_arg.
|
|
*/
|
|
atomic_add_int(&smp_rv_waiters[3], 1);
|
|
|
|
td->td_critnest--;
|
|
KASSERT(owepreempt == td->td_owepreempt,
|
|
("rendezvous action changed td_owepreempt"));
|
|
}
|
|
|
|
void
|
|
smp_rendezvous_cpus(cpuset_t map,
|
|
void (* setup_func)(void *),
|
|
void (* action_func)(void *),
|
|
void (* teardown_func)(void *),
|
|
void *arg)
|
|
{
|
|
int curcpumap, i, ncpus = 0;
|
|
|
|
/* Look comments in the !SMP case. */
|
|
if (!smp_started) {
|
|
spinlock_enter();
|
|
if (setup_func != NULL)
|
|
setup_func(arg);
|
|
if (action_func != NULL)
|
|
action_func(arg);
|
|
if (teardown_func != NULL)
|
|
teardown_func(arg);
|
|
spinlock_exit();
|
|
return;
|
|
}
|
|
|
|
CPU_FOREACH(i) {
|
|
if (CPU_ISSET(i, &map))
|
|
ncpus++;
|
|
}
|
|
if (ncpus == 0)
|
|
panic("ncpus is 0 with non-zero map");
|
|
|
|
mtx_lock_spin(&smp_ipi_mtx);
|
|
|
|
/* Pass rendezvous parameters via global variables. */
|
|
smp_rv_ncpus = ncpus;
|
|
smp_rv_setup_func = setup_func;
|
|
smp_rv_action_func = action_func;
|
|
smp_rv_teardown_func = teardown_func;
|
|
smp_rv_func_arg = arg;
|
|
smp_rv_waiters[1] = 0;
|
|
smp_rv_waiters[2] = 0;
|
|
smp_rv_waiters[3] = 0;
|
|
atomic_store_rel_int(&smp_rv_waiters[0], 0);
|
|
|
|
/*
|
|
* Signal other processors, which will enter the IPI with
|
|
* interrupts off.
|
|
*/
|
|
curcpumap = CPU_ISSET(curcpu, &map);
|
|
CPU_CLR(curcpu, &map);
|
|
ipi_selected(map, IPI_RENDEZVOUS);
|
|
|
|
/* Check if the current CPU is in the map */
|
|
if (curcpumap != 0)
|
|
smp_rendezvous_action();
|
|
|
|
/*
|
|
* Ensure that the master CPU waits for all the other
|
|
* CPUs to finish the rendezvous, so that smp_rv_*
|
|
* pseudo-structure and the arg are guaranteed to not
|
|
* be in use.
|
|
*/
|
|
while (atomic_load_acq_int(&smp_rv_waiters[3]) < ncpus)
|
|
cpu_spinwait();
|
|
|
|
mtx_unlock_spin(&smp_ipi_mtx);
|
|
}
|
|
|
|
void
|
|
smp_rendezvous(void (* setup_func)(void *),
|
|
void (* action_func)(void *),
|
|
void (* teardown_func)(void *),
|
|
void *arg)
|
|
{
|
|
smp_rendezvous_cpus(all_cpus, setup_func, action_func, teardown_func, arg);
|
|
}
|
|
|
|
static struct cpu_group group[MAXCPU];
|
|
|
|
struct cpu_group *
|
|
smp_topo(void)
|
|
{
|
|
char cpusetbuf[CPUSETBUFSIZ], cpusetbuf2[CPUSETBUFSIZ];
|
|
struct cpu_group *top;
|
|
|
|
/*
|
|
* Check for a fake topology request for debugging purposes.
|
|
*/
|
|
switch (smp_topology) {
|
|
case 1:
|
|
/* Dual core with no sharing. */
|
|
top = smp_topo_1level(CG_SHARE_NONE, 2, 0);
|
|
break;
|
|
case 2:
|
|
/* No topology, all cpus are equal. */
|
|
top = smp_topo_none();
|
|
break;
|
|
case 3:
|
|
/* Dual core with shared L2. */
|
|
top = smp_topo_1level(CG_SHARE_L2, 2, 0);
|
|
break;
|
|
case 4:
|
|
/* quad core, shared l3 among each package, private l2. */
|
|
top = smp_topo_1level(CG_SHARE_L3, 4, 0);
|
|
break;
|
|
case 5:
|
|
/* quad core, 2 dualcore parts on each package share l2. */
|
|
top = smp_topo_2level(CG_SHARE_NONE, 2, CG_SHARE_L2, 2, 0);
|
|
break;
|
|
case 6:
|
|
/* Single-core 2xHTT */
|
|
top = smp_topo_1level(CG_SHARE_L1, 2, CG_FLAG_HTT);
|
|
break;
|
|
case 7:
|
|
/* quad core with a shared l3, 8 threads sharing L2. */
|
|
top = smp_topo_2level(CG_SHARE_L3, 4, CG_SHARE_L2, 8,
|
|
CG_FLAG_SMT);
|
|
break;
|
|
default:
|
|
/* Default, ask the system what it wants. */
|
|
top = cpu_topo();
|
|
break;
|
|
}
|
|
/*
|
|
* Verify the returned topology.
|
|
*/
|
|
if (top->cg_count != mp_ncpus)
|
|
panic("Built bad topology at %p. CPU count %d != %d",
|
|
top, top->cg_count, mp_ncpus);
|
|
if (CPU_CMP(&top->cg_mask, &all_cpus))
|
|
panic("Built bad topology at %p. CPU mask (%s) != (%s)",
|
|
top, cpusetobj_strprint(cpusetbuf, &top->cg_mask),
|
|
cpusetobj_strprint(cpusetbuf2, &all_cpus));
|
|
return (top);
|
|
}
|
|
|
|
struct cpu_group *
|
|
smp_topo_none(void)
|
|
{
|
|
struct cpu_group *top;
|
|
|
|
top = &group[0];
|
|
top->cg_parent = NULL;
|
|
top->cg_child = NULL;
|
|
top->cg_mask = all_cpus;
|
|
top->cg_count = mp_ncpus;
|
|
top->cg_children = 0;
|
|
top->cg_level = CG_SHARE_NONE;
|
|
top->cg_flags = 0;
|
|
|
|
return (top);
|
|
}
|
|
|
|
static int
|
|
smp_topo_addleaf(struct cpu_group *parent, struct cpu_group *child, int share,
|
|
int count, int flags, int start)
|
|
{
|
|
char cpusetbuf[CPUSETBUFSIZ], cpusetbuf2[CPUSETBUFSIZ];
|
|
cpuset_t mask;
|
|
int i;
|
|
|
|
CPU_ZERO(&mask);
|
|
for (i = 0; i < count; i++, start++)
|
|
CPU_SET(start, &mask);
|
|
child->cg_parent = parent;
|
|
child->cg_child = NULL;
|
|
child->cg_children = 0;
|
|
child->cg_level = share;
|
|
child->cg_count = count;
|
|
child->cg_flags = flags;
|
|
child->cg_mask = mask;
|
|
parent->cg_children++;
|
|
for (; parent != NULL; parent = parent->cg_parent) {
|
|
if (CPU_OVERLAP(&parent->cg_mask, &child->cg_mask))
|
|
panic("Duplicate children in %p. mask (%s) child (%s)",
|
|
parent,
|
|
cpusetobj_strprint(cpusetbuf, &parent->cg_mask),
|
|
cpusetobj_strprint(cpusetbuf2, &child->cg_mask));
|
|
CPU_OR(&parent->cg_mask, &child->cg_mask);
|
|
parent->cg_count += child->cg_count;
|
|
}
|
|
|
|
return (start);
|
|
}
|
|
|
|
struct cpu_group *
|
|
smp_topo_1level(int share, int count, int flags)
|
|
{
|
|
struct cpu_group *child;
|
|
struct cpu_group *top;
|
|
int packages;
|
|
int cpu;
|
|
int i;
|
|
|
|
cpu = 0;
|
|
top = &group[0];
|
|
packages = mp_ncpus / count;
|
|
top->cg_child = child = &group[1];
|
|
top->cg_level = CG_SHARE_NONE;
|
|
for (i = 0; i < packages; i++, child++)
|
|
cpu = smp_topo_addleaf(top, child, share, count, flags, cpu);
|
|
return (top);
|
|
}
|
|
|
|
struct cpu_group *
|
|
smp_topo_2level(int l2share, int l2count, int l1share, int l1count,
|
|
int l1flags)
|
|
{
|
|
struct cpu_group *top;
|
|
struct cpu_group *l1g;
|
|
struct cpu_group *l2g;
|
|
int cpu;
|
|
int i;
|
|
int j;
|
|
|
|
cpu = 0;
|
|
top = &group[0];
|
|
l2g = &group[1];
|
|
top->cg_child = l2g;
|
|
top->cg_level = CG_SHARE_NONE;
|
|
top->cg_children = mp_ncpus / (l2count * l1count);
|
|
l1g = l2g + top->cg_children;
|
|
for (i = 0; i < top->cg_children; i++, l2g++) {
|
|
l2g->cg_parent = top;
|
|
l2g->cg_child = l1g;
|
|
l2g->cg_level = l2share;
|
|
for (j = 0; j < l2count; j++, l1g++)
|
|
cpu = smp_topo_addleaf(l2g, l1g, l1share, l1count,
|
|
l1flags, cpu);
|
|
}
|
|
return (top);
|
|
}
|
|
|
|
|
|
struct cpu_group *
|
|
smp_topo_find(struct cpu_group *top, int cpu)
|
|
{
|
|
struct cpu_group *cg;
|
|
cpuset_t mask;
|
|
int children;
|
|
int i;
|
|
|
|
CPU_SETOF(cpu, &mask);
|
|
cg = top;
|
|
for (;;) {
|
|
if (!CPU_OVERLAP(&cg->cg_mask, &mask))
|
|
return (NULL);
|
|
if (cg->cg_children == 0)
|
|
return (cg);
|
|
children = cg->cg_children;
|
|
for (i = 0, cg = cg->cg_child; i < children; cg++, i++)
|
|
if (CPU_OVERLAP(&cg->cg_mask, &mask))
|
|
break;
|
|
}
|
|
return (NULL);
|
|
}
|
|
#else /* !SMP */
|
|
|
|
void
|
|
smp_rendezvous_cpus(cpuset_t map,
|
|
void (*setup_func)(void *),
|
|
void (*action_func)(void *),
|
|
void (*teardown_func)(void *),
|
|
void *arg)
|
|
{
|
|
/*
|
|
* In the !SMP case we just need to ensure the same initial conditions
|
|
* as the SMP case.
|
|
*/
|
|
spinlock_enter();
|
|
if (setup_func != NULL)
|
|
setup_func(arg);
|
|
if (action_func != NULL)
|
|
action_func(arg);
|
|
if (teardown_func != NULL)
|
|
teardown_func(arg);
|
|
spinlock_exit();
|
|
}
|
|
|
|
void
|
|
smp_rendezvous(void (*setup_func)(void *),
|
|
void (*action_func)(void *),
|
|
void (*teardown_func)(void *),
|
|
void *arg)
|
|
{
|
|
|
|
/* Look comments in the smp_rendezvous_cpus() case. */
|
|
spinlock_enter();
|
|
if (setup_func != NULL)
|
|
setup_func(arg);
|
|
if (action_func != NULL)
|
|
action_func(arg);
|
|
if (teardown_func != NULL)
|
|
teardown_func(arg);
|
|
spinlock_exit();
|
|
}
|
|
|
|
/*
|
|
* Provide dummy SMP support for UP kernels. Modules that need to use SMP
|
|
* APIs will still work using this dummy support.
|
|
*/
|
|
static void
|
|
mp_setvariables_for_up(void *dummy)
|
|
{
|
|
mp_ncpus = 1;
|
|
mp_maxid = PCPU_GET(cpuid);
|
|
CPU_SETOF(mp_maxid, &all_cpus);
|
|
KASSERT(PCPU_GET(cpuid) == 0, ("UP must have a CPU ID of zero"));
|
|
}
|
|
SYSINIT(cpu_mp_setvariables, SI_SUB_TUNABLES, SI_ORDER_FIRST,
|
|
mp_setvariables_for_up, NULL);
|
|
#endif /* SMP */
|
|
|
|
void
|
|
smp_no_rendevous_barrier(void *dummy)
|
|
{
|
|
#ifdef SMP
|
|
KASSERT((!smp_started),("smp_no_rendevous called and smp is started"));
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Wait specified idle threads to switch once. This ensures that even
|
|
* preempted threads have cycled through the switch function once,
|
|
* exiting their codepaths. This allows us to change global pointers
|
|
* with no other synchronization.
|
|
*/
|
|
int
|
|
quiesce_cpus(cpuset_t map, const char *wmesg, int prio)
|
|
{
|
|
struct pcpu *pcpu;
|
|
u_int gen[MAXCPU];
|
|
int error;
|
|
int cpu;
|
|
|
|
error = 0;
|
|
for (cpu = 0; cpu <= mp_maxid; cpu++) {
|
|
if (!CPU_ISSET(cpu, &map) || CPU_ABSENT(cpu))
|
|
continue;
|
|
pcpu = pcpu_find(cpu);
|
|
gen[cpu] = pcpu->pc_idlethread->td_generation;
|
|
}
|
|
for (cpu = 0; cpu <= mp_maxid; cpu++) {
|
|
if (!CPU_ISSET(cpu, &map) || CPU_ABSENT(cpu))
|
|
continue;
|
|
pcpu = pcpu_find(cpu);
|
|
thread_lock(curthread);
|
|
sched_bind(curthread, cpu);
|
|
thread_unlock(curthread);
|
|
while (gen[cpu] == pcpu->pc_idlethread->td_generation) {
|
|
error = tsleep(quiesce_cpus, prio, wmesg, 1);
|
|
if (error != EWOULDBLOCK)
|
|
goto out;
|
|
error = 0;
|
|
}
|
|
}
|
|
out:
|
|
thread_lock(curthread);
|
|
sched_unbind(curthread);
|
|
thread_unlock(curthread);
|
|
|
|
return (error);
|
|
}
|
|
|
|
int
|
|
quiesce_all_cpus(const char *wmesg, int prio)
|
|
{
|
|
|
|
return quiesce_cpus(all_cpus, wmesg, prio);
|
|
}
|