diff options
Diffstat (limited to 'sys/kern/subr_smp.c')
| -rw-r--r-- | sys/kern/subr_smp.c | 117 |
1 files changed, 90 insertions, 27 deletions
diff --git a/sys/kern/subr_smp.c b/sys/kern/subr_smp.c index 75378f8dad36..375aed7eb4ab 100644 --- a/sys/kern/subr_smp.c +++ b/sys/kern/subr_smp.c @@ -74,6 +74,9 @@ u_int mp_maxid; SYSCTL_NODE(_kern, OID_AUTO, smp, CTLFLAG_RD, NULL, "Kernel SMP"); +SYSCTL_INT(_kern_smp, OID_AUTO, maxid, CTLFLAG_RD, &mp_maxid, 0, + "Max CPU ID."); + SYSCTL_INT(_kern_smp, OID_AUTO, maxcpus, CTLFLAG_RD, &mp_maxcpus, 0, "Max number of CPUs that the system was compiled for."); @@ -104,10 +107,11 @@ SYSCTL_INT(_kern_smp, OID_AUTO, forward_roundrobin_enabled, CTLFLAG_RW, "Forwarding of roundrobin to all other CPUs"); /* Variables needed for SMP rendezvous. */ -static void (*smp_rv_setup_func)(void *arg); -static void (*smp_rv_action_func)(void *arg); -static void (*smp_rv_teardown_func)(void *arg); -static void *smp_rv_func_arg; +static volatile cpumask_t smp_rv_cpumask; +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[3]; /* @@ -286,6 +290,14 @@ restart_cpus(cpumask_t map) return 1; } +void +smp_no_rendevous_barrier(void *dummy) +{ +#ifdef SMP + KASSERT((!smp_started),("smp_no_rendevous called and smp is started")); +#endif +} + /* * All-CPU rendezvous. CPUs are signalled, all execute the setup function * (if specified), rendezvous, execute the action function (if specified), @@ -298,41 +310,57 @@ restart_cpus(cpumask_t map) void smp_rendezvous_action(void) { + cpumask_t map = smp_rv_cpumask; + int i, ncpus = 0; + void* local_func_arg = smp_rv_func_arg; + void (*local_setup_func)(void*) = smp_rv_setup_func; + void (*local_action_func)(void*) = smp_rv_action_func; + void (*local_teardown_func)(void*) = smp_rv_teardown_func; + + for (i = 0; i < MAXCPU; i++) + if (((1 << i) & map) != 0 && pcpu_find(i) != NULL) + ncpus++; /* Ensure we have up-to-date values. */ atomic_add_acq_int(&smp_rv_waiters[0], 1); - while (smp_rv_waiters[0] < mp_ncpus) + while (smp_rv_waiters[0] < ncpus) cpu_spinwait(); /* setup function */ - if (smp_rv_setup_func != NULL) - smp_rv_setup_func(smp_rv_func_arg); - - /* spin on entry rendezvous */ - atomic_add_int(&smp_rv_waiters[1], 1); - while (smp_rv_waiters[1] < mp_ncpus) - cpu_spinwait(); + if (local_setup_func != smp_no_rendevous_barrier) { + if (smp_rv_setup_func != NULL) + smp_rv_setup_func(smp_rv_func_arg); + + /* spin on entry rendezvous */ + atomic_add_int(&smp_rv_waiters[1], 1); + while (smp_rv_waiters[1] < ncpus) + cpu_spinwait(); + } /* action function */ - if (smp_rv_action_func != NULL) - smp_rv_action_func(smp_rv_func_arg); + if (local_action_func != NULL) + local_action_func(local_func_arg); /* spin on exit rendezvous */ atomic_add_int(&smp_rv_waiters[2], 1); - while (smp_rv_waiters[2] < mp_ncpus) + if (local_teardown_func == smp_no_rendevous_barrier) + return; + while (smp_rv_waiters[2] < ncpus) cpu_spinwait(); /* teardown function */ - if (smp_rv_teardown_func != NULL) - smp_rv_teardown_func(smp_rv_func_arg); + if (local_teardown_func != NULL) + local_teardown_func(local_func_arg); } void -smp_rendezvous(void (* setup_func)(void *), - void (* action_func)(void *), - void (* teardown_func)(void *), - void *arg) +smp_rendezvous_cpus(cpumask_t map, + void (* setup_func)(void *), + void (* action_func)(void *), + void (* teardown_func)(void *), + void *arg) { + int i, ncpus = 0; if (!smp_started) { if (setup_func != NULL) @@ -343,11 +371,16 @@ smp_rendezvous(void (* setup_func)(void *), teardown_func(arg); return; } + + for (i = 0; i < MAXCPU; i++) + if (((1 << i) & map) != 0 && pcpu_find(i) != NULL) + ncpus++; /* obtain rendezvous lock */ mtx_lock_spin(&smp_ipi_mtx); /* set static function pointers */ + smp_rv_cpumask = map & ~(1 << curcpu); smp_rv_setup_func = setup_func; smp_rv_action_func = action_func; smp_rv_teardown_func = teardown_func; @@ -357,14 +390,29 @@ smp_rendezvous(void (* setup_func)(void *), atomic_store_rel_int(&smp_rv_waiters[0], 0); /* signal other processors, which will enter the IPI with interrupts off */ - ipi_all_but_self(IPI_RENDEZVOUS); + ipi_selected(map, IPI_RENDEZVOUS); + + /* Check if the current CPU is in the map */ + if ((map & (1 << curcpu)) != 0) + /* call executor function for the current CPU */ + smp_rendezvous_action(); - /* call executor function */ - smp_rendezvous_action(); + if (teardown_func == smp_no_rendevous_barrier) + while (atomic_load_acq_int(&smp_rv_waiters[2]) < ncpus) + cpu_spinwait(); /* release lock */ 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); +} #else /* !SMP */ /* @@ -383,9 +431,24 @@ SYSINIT(cpu_mp_setvariables, SI_SUB_TUNABLES, SI_ORDER_FIRST, mp_setvariables_for_up, NULL); void -smp_rendezvous(void (* setup_func)(void *), - void (* action_func)(void *), - void (* teardown_func)(void *), +smp_rendezvous_cpus(cpumask_t map, + void (*setup_func)(void *), + void (*action_func)(void *), + void (*teardown_func)(void *), + void *arg) +{ + if (setup_func != NULL) + setup_func(arg); + if (action_func != NULL) + action_func(arg); + if (teardown_func != NULL) + teardown_func(arg); +} + +void +smp_rendezvous(void (*setup_func)(void *), + void (*action_func)(void *), + void (*teardown_func)(void *), void *arg) { |