Index: amd64/amd64/cpu_switch.S =================================================================== RCS file: /usr/home/ncvs/src/sys/amd64/amd64/cpu_switch.S,v retrieving revision 1.158 diff -u -r1.158 cpu_switch.S --- amd64/amd64/cpu_switch.S 6 Jun 2007 07:35:07 -0000 1.158 +++ amd64/amd64/cpu_switch.S 2 Jul 2007 05:43:31 -0000 @@ -148,13 +148,7 @@ movq %cr3,%rax cmpq %rcx,%rax /* Same address space? */ jne swinact - movq %rdx, TD_LOCK(%rdi) /* Release the old thread */ - /* Wait for the new thread to become unblocked */ - movq $blocked_lock, %rdx -1: - movq TD_LOCK(%rsi),%rcx - cmpq %rcx, %rdx - je 1b + xchgq %rdx, TD_LOCK(%rdi) /* Release the old thread */ jmp sw1 swinact: movq %rcx,%cr3 /* new address space */ @@ -165,19 +159,21 @@ LK btrl %eax, VM_PMAP+PM_ACTIVE(%rcx) /* clear old */ movq %rdx, TD_LOCK(%rdi) /* Release the old thread */ swact: + /* Set bit in new pmap->pm_active */ + movq TD_PROC(%rsi),%rdx /* newproc */ + movq P_VMSPACE(%rdx), %rdx + LK btsl %eax, VM_PMAP+PM_ACTIVE(%rdx) /* set new */ + +sw1: /* Wait for the new thread to become unblocked */ movq $blocked_lock, %rdx 1: + lfence movq TD_LOCK(%rsi),%rcx cmpq %rcx, %rdx + pause je 1b - /* Set bit in new pmap->pm_active */ - movq TD_PROC(%rsi),%rdx /* newproc */ - movq P_VMSPACE(%rdx), %rdx - LK btsl %eax, VM_PMAP+PM_ACTIVE(%rdx) /* set new */ - -sw1: /* * At this point, we've switched address spaces and are ready * to load up the rest of the next context. Index: conf/NOTES =================================================================== RCS file: /usr/home/ncvs/src/sys/conf/NOTES,v retrieving revision 1.1438 diff -u -r1.1438 NOTES --- conf/NOTES 29 Jun 2007 22:47:16 -0000 1.1438 +++ conf/NOTES 2 Jul 2007 05:43:32 -0000 @@ -183,6 +183,7 @@ # options SCHED_4BSD #options SCHED_ULE +#options SCHED_SMP ##################################################################### # SMP OPTIONS: Index: conf/files =================================================================== RCS file: /usr/home/ncvs/src/sys/conf/files,v retrieving revision 1.1225 diff -u -r1.1225 files --- conf/files 29 Jun 2007 22:47:16 -0000 1.1225 +++ conf/files 2 Jul 2007 05:43:32 -0000 @@ -1443,6 +1443,7 @@ kern/p1003_1b.c standard kern/posix4_mib.c standard kern/sched_4bsd.c optional sched_4bsd +kern/sched_smp.c optional sched_smp kern/sched_ule.c optional sched_ule kern/serdev_if.m standard kern/subr_acl_posix1e.c standard Index: conf/options =================================================================== RCS file: /usr/home/ncvs/src/sys/conf/options,v retrieving revision 1.597 diff -u -r1.597 options --- conf/options 25 Jun 2007 05:06:55 -0000 1.597 +++ conf/options 2 Jul 2007 05:43:32 -0000 @@ -73,6 +73,7 @@ DIRECTIO FULL_PREEMPTION opt_sched.h IPI_PREEMPTION opt_sched.h +SCHED_STATS opt_sched.h GEOM_AES opt_geom.h GEOM_BDE opt_geom.h GEOM_BSD opt_geom.h @@ -135,6 +136,7 @@ PREEMPTION opt_sched.h QUOTA SCHED_4BSD opt_sched.h +SCHED_SMP opt_sched.h SCHED_ULE opt_sched.h SHOW_BUSYBUFS SLEEPQUEUE_PROFILING Index: i386/i386/genassym.c =================================================================== RCS file: /usr/home/ncvs/src/sys/i386/i386/genassym.c,v retrieving revision 1.157 diff -u -r1.157 genassym.c --- i386/i386/genassym.c 6 Jun 2007 07:35:07 -0000 1.157 +++ i386/i386/genassym.c 2 Jul 2007 05:43:36 -0000 @@ -81,6 +81,7 @@ ASSYM(P_SFLAG, offsetof(struct proc, p_sflag)); ASSYM(TD_FLAGS, offsetof(struct thread, td_flags)); +ASSYM(TD_LOCK, offsetof(struct thread, td_lock)); ASSYM(TD_PCB, offsetof(struct thread, td_pcb)); ASSYM(TD_PROC, offsetof(struct thread, td_proc)); ASSYM(TD_MD, offsetof(struct thread, td_md)); Index: i386/i386/swtch.s =================================================================== RCS file: /usr/home/ncvs/src/sys/i386/i386/swtch.s,v retrieving revision 1.154 diff -u -r1.154 swtch.s --- i386/i386/swtch.s 6 Jun 2007 07:35:07 -0000 1.154 +++ i386/i386/swtch.s 2 Jul 2007 05:43:36 -0000 @@ -33,6 +33,7 @@ */ #include "opt_npx.h" +#include "opt_sched.h" #include @@ -91,6 +92,7 @@ * 0(%esp) = ret * 4(%esp) = oldtd * 8(%esp) = newtd + * 12(%esp) = newlock */ ENTRY(cpu_switch) @@ -145,13 +147,16 @@ #endif /* Save is done. Now fire up new thread. Leave old vmspace. */ +#ifdef SCHED_SMP + movl 4(%esp),%edi + movl 12(%esp),%esi /* New td_lock */ +#endif movl 8(%esp),%ecx /* New thread */ #ifdef INVARIANTS testl %ecx,%ecx /* no thread? */ jz badsw3 /* no, panic */ #endif movl TD_PCB(%ecx),%edx - movl PCPU(CPUID), %esi /* switch address space */ movl PCB_CR3(%edx),%eax @@ -160,11 +165,32 @@ #else cmpl %eax,IdlePTD /* Kernel address space? */ #endif +#ifdef SCHED_SMP + je sw0 + movl %cr3,%ebx /* The same address space? */ + cmpl %ebx,%eax + je sw0 + movl %eax,%cr3 /* new address space */ + movl %esi,%eax + movl PCPU(CPUID), %esi + + xchgl %eax,TD_LOCK(%edi) /* _rel memory barrier */ + movl $blocked_lock,%eax +1: + lock + cmpxchgl %eax,TD_LOCK(%ecx) /* _acq memory barrier */ + jne 2f + pause + jmp 1b +2: +#else je sw1 movl %cr3,%ebx /* The same address space? */ cmpl %ebx,%eax je sw1 movl %eax,%cr3 /* new address space */ + movl PCPU(CPUID), %esi +#endif /* Release bit from old pmap->pm_active */ movl PCPU(CURPMAP), %ebx @@ -183,6 +209,18 @@ #endif btsl %esi, PM_ACTIVE(%ebx) /* set new */ +#ifdef SCHED_SMP + jmp sw1 +sw0: + xchgl %esi,TD_LOCK(%edi) /* _rel memory barrier */ + movl $blocked_lock,%eax +1: + lock + cmpxchgl %eax,TD_LOCK(%ecx) /* _acq memory barrier */ + jne sw1 + pause + jmp 1b +#endif sw1: /* * At this point, we've switched address spaces and are ready Index: kern/sched_smp.c =================================================================== RCS file: kern/sched_smp.c diff -N kern/sched_smp.c --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ kern/sched_smp.c 2 Jul 2007 05:43:37 -0000 @@ -0,0 +1,2386 @@ +/*- + * Copyright (c) 2002-2007, Jeffrey Roberson + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice unmodified, this list of conditions, and the following + * disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include +__FBSDID("$FreeBSD: src/sys/kern/sched_ule.c,v 1.192 2007/04/20 05:45:46 kmacy Exp $"); + +#include "opt_hwpmc_hooks.h" +#include "opt_sched.h" + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#ifdef KTRACE +#include +#include +#endif + +#ifdef HWPMC_HOOKS +#include +#endif + +#include +#include + +#ifndef PREEMPTION +#error "SCHED_ULE requires options PREEMPTION" +#endif + +/* + * TODO: + * Pick idle from affinity group or self group first. + * Implement pick_score. + */ + +#define KTR_ULE 0 + +/* + * Thread scheduler specific section. + */ +struct td_sched { + TAILQ_ENTRY(td_sched) ts_procq; /* (j/z) Run queue. */ + int ts_flags; /* (j) TSF_* flags. */ + struct thread *ts_thread; /* (*) Active associated thread. */ + u_char ts_rqindex; /* (j) Run queue index. */ + int ts_slptime; + int ts_slice; + struct runq *ts_runq; + u_char ts_cpu; /* CPU that we have affinity for. */ + /* The following variables are only used for pctcpu calculation */ + int ts_ltick; /* Last tick that we were running on */ + int ts_ftick; /* First tick that we were running on */ + int ts_ticks; /* Tick count */ +#ifdef SMP + int ts_rltick; /* Real last tick, for affinity. */ +#endif + + /* originally from kg_sched */ + u_int skg_slptime; /* Number of ticks we vol. slept */ + u_int skg_runtime; /* Number of ticks we were running */ +}; +/* flags kept in ts_flags */ +#define TSF_BOUND 0x0001 /* Thread can not migrate. */ +#define TSF_XFERABLE 0x0002 /* Thread was added as transferable. */ + +static struct td_sched td_sched0; + +/* + * Cpu percentage computation macros and defines. + * + * SCHED_TICK_SECS: Number of seconds to average the cpu usage across. + * SCHED_TICK_TARG: Number of hz ticks to average the cpu usage across. + * SCHED_TICK_MAX: Maximum number of ticks before scaling back. + * SCHED_TICK_SHIFT: Shift factor to avoid rounding away results. + * SCHED_TICK_HZ: Compute the number of hz ticks for a given ticks count. + * SCHED_TICK_TOTAL: Gives the amount of time we've been recording ticks. + */ +#define SCHED_TICK_SECS 10 +#define SCHED_TICK_TARG (hz * SCHED_TICK_SECS) +#define SCHED_TICK_MAX (SCHED_TICK_TARG + hz) +#define SCHED_TICK_SHIFT 10 +#define SCHED_TICK_HZ(ts) ((ts)->ts_ticks >> SCHED_TICK_SHIFT) +#define SCHED_TICK_TOTAL(ts) (max((ts)->ts_ltick - (ts)->ts_ftick, hz)) + +/* + * These macros determine priorities for non-interactive threads. They are + * assigned a priority based on their recent cpu utilization as expressed + * by the ratio of ticks to the tick total. NHALF priorities at the start + * and end of the MIN to MAX timeshare range are only reachable with negative + * or positive nice respectively. + * + * PRI_RANGE: Priority range for utilization dependent priorities. + * PRI_NRESV: Number of nice values. + * PRI_TICKS: Compute a priority in PRI_RANGE from the ticks count and total. + * PRI_NICE: Determines the part of the priority inherited from nice. + */ +#define SCHED_PRI_NRESV (PRIO_MAX - PRIO_MIN) +#define SCHED_PRI_NHALF (SCHED_PRI_NRESV / 2) +#define SCHED_PRI_MIN (PRI_MIN_TIMESHARE + SCHED_PRI_NHALF) +#define SCHED_PRI_MAX (PRI_MAX_TIMESHARE - SCHED_PRI_NHALF) +#define SCHED_PRI_RANGE (SCHED_PRI_MAX - SCHED_PRI_MIN) +#define SCHED_PRI_TICKS(ts) \ + (SCHED_TICK_HZ((ts)) / \ + (roundup(SCHED_TICK_TOTAL((ts)), SCHED_PRI_RANGE) / SCHED_PRI_RANGE)) +#define SCHED_PRI_NICE(nice) (nice) + +/* + * These determine the interactivity of a process. Interactivity differs from + * cpu utilization in that it expresses the voluntary time slept vs time ran + * while cpu utilization includes all time not running. This more accurately + * models the intent of the thread. + * + * SLP_RUN_MAX: Maximum amount of sleep time + run time we'll accumulate + * before throttling back. + * SLP_RUN_FORK: Maximum slp+run time to inherit at fork time. + * INTERACT_MAX: Maximum interactivity value. Smaller is better. + * INTERACT_THRESH: Threshhold for placement on the current runq. + */ +#define SCHED_SLP_RUN_MAX ((hz * 5) << SCHED_TICK_SHIFT) +#define SCHED_SLP_RUN_FORK ((hz / 2) << SCHED_TICK_SHIFT) +#define SCHED_INTERACT_MAX (100) +#define SCHED_INTERACT_HALF (SCHED_INTERACT_MAX / 2) +#define SCHED_INTERACT_THRESH (30) + +/* + * tickincr: Converts a stathz tick into a hz domain scaled by + * the shift factor. Without the shift the error rate + * due to rounding would be unacceptably high. + * realstathz: stathz is sometimes 0 and run off of hz. + * sched_slice: Runtime of each thread before rescheduling. + * preempt_thresh: Priority threshold for preemption and remote IPIs. + */ +static int sched_interact = SCHED_INTERACT_THRESH; +static int realstathz; +static int tickincr; +static int sched_slice; +static int preempt_thresh = PRI_MIN_KERN; + +#define SCHED_BAL_SECS 2 /* How often we run the rebalance algorithm. */ + +/* + * tdq - per processor runqs and statistics. + */ +struct tdq { + struct mtx tdq_lock; /* Protects all fields below. */ + struct runq tdq_idle; /* Queue of IDLE threads. */ + struct runq tdq_timeshare; /* timeshare run queue. */ + struct runq tdq_realtime; /* real-time run queue. */ + int tdq_load; /* Aggregate load. */ + u_char tdq_idx; /* Current insert index. */ + u_char tdq_ridx; /* Current removal index. */ +#ifdef SMP + u_char tdq_lowpri; /* Lowest priority thread */ + int tdq_transferable; + LIST_ENTRY(tdq) tdq_siblings; /* Next in tdq group. */ + struct tdq_group *tdq_group; /* Our processor group. */ +#else + int tdq_sysload; /* For loadavg, !ITHD load. */ +#endif + char tdq_name[32]; /* lock name */ + char tdq_runname[32]; /* run lock name */ + /* + * tdq_runlock is purposefully placed where it will be in it's own + * cacheline. + */ + struct mtx tdq_runlock; /* Protects running thread. */ +} __aligned(64); + + +#ifdef SMP +/* + * tdq groups are groups of processors which can cheaply share threads. When + * one processor in the group goes idle it will check the runqs of the other + * processors in its group prior to halting and waiting for an interrupt. + * These groups are suitable for SMT (Symetric Multi-Threading) and not NUMA. + * In a numa environment we'd want an idle bitmap per group and a two tiered + * load balancer. + */ +struct tdq_group { + int tdg_cpus; /* Count of CPUs in this tdq group. */ + cpumask_t tdg_cpumask; /* Mask of cpus in this group. */ + cpumask_t tdg_idlemask; /* Idle cpus in this group. */ + cpumask_t tdg_mask; /* Bit mask for first cpu. */ + int tdg_load; /* Total load of this group. */ + int tdg_transferable; /* Transferable load of this group. */ + LIST_HEAD(, tdq) tdg_members; /* Linked list of all members. */ +} __aligned(64); + +#define SCHED_AFFINITY_DEFAULT (max(1, hz / 300)) +#define SCHED_AFFINITY(ts) ((ts)->ts_rltick > ticks - affinity) + +/* + * Run-time tunables. + */ +static int rebalance = 0; +static int pick_pri = 0; +static int pick_mysql = 0; +static int affinity; +static int tryself = 1; +static int tryselfidle = 1; +static int steal_htt = 0; +static int steal_busy = 0; +static int topology = 0; + +/* + * One thread queue per processor. + */ +static volatile cpumask_t tdq_idle; +static int tdg_maxid; +static struct tdq tdq_cpu[MAXCPU]; +static struct tdq_group tdq_groups[MAXCPU]; +static int bal_tick; +static int gbal_tick; +static int balance_groups; + +#define TDQ_SELF() (&tdq_cpu[PCPU_GET(cpuid)]) +#define TDQ_CPU(x) (&tdq_cpu[(x)]) +#define TDQ_ID(x) ((x) - tdq_cpu) +#define TDQ_GROUP(x) (&tdq_groups[(x)]) +#else /* !SMP */ +static struct tdq tdq_cpu; + +#define TDQ_ID(x) (0) +#define TDQ_SELF() (&tdq_cpu) +#define TDQ_CPU(x) (&tdq_cpu) +#endif + +#define TDQ_LOCK_ASSERT(t, type) mtx_assert(TDQ_LOCKPTR((t)), (type)) +#define TDQ_LOCK(t) mtx_lock_spin(TDQ_LOCKPTR((t))) +#define TDQ_LOCK_FLAGS(t, f) mtx_lock_spin_flags(TDQ_LOCKPTR((t)), (f)) +#define TDQ_UNLOCK(t) mtx_unlock_spin(TDQ_LOCKPTR((t))) +#define TDQ_LOCKPTR(t) (&(t)->tdq_lock) + +#define TDQ_RUN_LOCK_ASSERT(t, type) mtx_assert(TDQ_RUN_LOCKPTR((t)), (type)) +#define TDQ_RUN_LOCK(t) mtx_lock_spin(TDQ_RUN_LOCKPTR((t))) +#define TDQ_RUN_LOCK_FLAGS(t, f) mtx_lock_spin_flags(TDQ_RUN_LOCKPTR((t)), (f)) +#define TDQ_RUN_UNLOCK(t) mtx_unlock_spin(TDQ_RUN_LOCKPTR((t))) +#define TDQ_RUN_LOCKPTR(t) (&(t)->tdq_runlock) + +static void sched_priority(struct thread *); +static void sched_thread_priority(struct thread *, u_char); +static int sched_interact_score(struct thread *); +static void sched_interact_update(struct thread *); +static void sched_interact_fork(struct thread *); +static void sched_pctcpu_update(struct td_sched *); + +/* Operations on per processor queues */ +static struct td_sched * tdq_choose(struct tdq *); +static void tdq_setup(struct tdq *); +static void tdq_load_add(struct tdq *, struct td_sched *); +static void tdq_load_rem(struct tdq *, struct td_sched *); +static __inline void tdq_runq_add(struct tdq *, struct td_sched *, int); +static __inline void tdq_runq_rem(struct tdq *, struct td_sched *); +void tdq_print(int cpu); +static void runq_print(struct runq *rq); +static void tdq_add(struct tdq *, struct thread *, int); +#ifdef SMP +static int tdq_pickcpu(struct td_sched *, int); +static void tdq_move(struct tdq *, struct tdq *); +static int tdq_idled(struct tdq *); +static void tdq_notify(struct td_sched *); +static struct td_sched *tdq_steal(struct tdq *, int); +static struct td_sched *runq_steal(struct runq *); +static void sched_balance(void); +static void sched_balance_groups(void); +static void sched_balance_group(struct tdq_group *); +static void sched_balance_pair(struct tdq *, struct tdq *); +static void sched_smp_tick(void); +static inline struct mtx *thread_block_switch(struct thread *); +static inline void thread_unblock_switch(struct thread *, struct mtx *); + + +#define THREAD_CAN_MIGRATE(td) ((td)->td_pinned == 0) +#endif + +static void sched_setup(void *dummy); +SYSINIT(sched_setup, SI_SUB_RUN_QUEUE, SI_ORDER_FIRST, sched_setup, NULL) + +static void sched_initticks(void *dummy); +SYSINIT(sched_initticks, SI_SUB_CLOCKS, SI_ORDER_THIRD, sched_initticks, NULL) + +static void +runq_print(struct runq *rq) +{ + struct rqhead *rqh; + struct td_sched *ts; + int pri; + int j; + int i; + + for (i = 0; i < RQB_LEN; i++) { + printf("\t\trunq bits %d 0x%zx\n", + i, rq->rq_status.rqb_bits[i]); + for (j = 0; j < RQB_BPW; j++) + if (rq->rq_status.rqb_bits[i] & (1ul << j)) { + pri = j + (i << RQB_L2BPW); + rqh = &rq->rq_queues[pri]; + TAILQ_FOREACH(ts, rqh, ts_procq) { + printf("\t\t\ttd %p(%s) priority %d rqindex %d pri %d\n", + ts->ts_thread, ts->ts_thread->td_proc->p_comm, ts->ts_thread->td_priority, ts->ts_rqindex, pri); + } + } + } +} + +void +tdq_print(int cpu) +{ + struct tdq *tdq; + + tdq = TDQ_CPU(cpu); + + printf("tdq:\n"); + printf("\tlockptr %p\n", TDQ_LOCKPTR(tdq)); + printf("\trun lockptr %p\n", TDQ_RUN_LOCKPTR(tdq)); + printf("\tlock name %s\n", tdq->tdq_name); + printf("\trun lock name %s\n", tdq->tdq_name); + printf("\tload: %d\n", tdq->tdq_load); + printf("\ttimeshare idx: %d\n", tdq->tdq_idx); + printf("\ttimeshare ridx: %d\n", tdq->tdq_ridx); + printf("\trealtime runq:\n"); + runq_print(&tdq->tdq_realtime); + printf("\ttimeshare runq:\n"); + runq_print(&tdq->tdq_timeshare); + printf("\tidle runq:\n"); + runq_print(&tdq->tdq_idle); +#ifdef SMP + printf("\tload transferable: %d\n", tdq->tdq_transferable); + printf("\tlowest priority: %d\n", tdq->tdq_lowpri); +#endif +} + +static __inline void +tdq_runq_add(struct tdq *tdq, struct td_sched *ts, int flags) +{ + TDQ_LOCK_ASSERT(tdq, MA_OWNED); + THREAD_LOCK_ASSERT(ts->ts_thread, MA_OWNED); +#ifdef SMP + if (THREAD_CAN_MIGRATE(ts->ts_thread)) { + tdq->tdq_transferable++; + tdq->tdq_group->tdg_transferable++; + ts->ts_flags |= TSF_XFERABLE; + } +#endif + if (ts->ts_runq == &tdq->tdq_timeshare) { + u_char pri; + + pri = ts->ts_thread->td_priority; + KASSERT(pri <= PRI_MAX_TIMESHARE && pri >= PRI_MIN_TIMESHARE, + ("Invalid priority %d on timeshare runq", pri)); + /* + * This queue contains only priorities between MIN and MAX + * realtime. Use the whole queue to represent these values. + */ +#define TS_RQ_PPQ (((PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE) + 1) / RQ_NQS) + if ((flags & SRQ_BORROWING) == 0) { + pri = (pri - PRI_MIN_TIMESHARE) / TS_RQ_PPQ; + pri = (pri + tdq->tdq_idx) % RQ_NQS; + /* + * This effectively shortens the queue by one so we + * can have a one slot difference between idx and + * ridx while we wait for threads to drain. + */ + if (tdq->tdq_ridx != tdq->tdq_idx && + pri == tdq->tdq_ridx) + pri = (unsigned char)(pri - 1) % RQ_NQS; + } else + pri = tdq->tdq_ridx; + runq_add_pri(ts->ts_runq, ts, pri, flags); + } else + runq_add(ts->ts_runq, ts, flags); +} + +static __inline void +tdq_runq_rem(struct tdq *tdq, struct td_sched *ts) +{ + TDQ_LOCK_ASSERT(tdq, MA_OWNED); + KASSERT(ts->ts_runq != NULL, + ("tdq_runq_remove: thread %p null ts_runq", ts->ts_thread)); +#ifdef SMP + if (ts->ts_flags & TSF_XFERABLE) { + tdq->tdq_transferable--; + tdq->tdq_group->tdg_transferable--; + ts->ts_flags &= ~TSF_XFERABLE; + } +#endif + if (ts->ts_runq == &tdq->tdq_timeshare) { + if (tdq->tdq_idx != tdq->tdq_ridx) + runq_remove_idx(ts->ts_runq, ts, &tdq->tdq_ridx); + else + runq_remove_idx(ts->ts_runq, ts, NULL); + /* + * For timeshare threads we update the priority here so + * the priority reflects the time we've been sleeping. + */ + ts->ts_ltick = ticks; + sched_pctcpu_update(ts); + sched_priority(ts->ts_thread); + } else + runq_remove(ts->ts_runq, ts); +} + +static void +tdq_load_add(struct tdq *tdq, struct td_sched *ts) +{ + int class; + + TDQ_LOCK_ASSERT(tdq, MA_OWNED); + THREAD_LOCK_ASSERT(ts->ts_thread, MA_OWNED); + class = PRI_BASE(ts->ts_thread->td_pri_class); + tdq->tdq_load++; + CTR2(KTR_SCHED, "cpu %jd load: %d", TDQ_ID(tdq), tdq->tdq_load); + if (class != PRI_ITHD && + (ts->ts_thread->td_proc->p_flag & P_NOLOAD) == 0) +#ifdef SMP + tdq->tdq_group->tdg_load++; +#else + tdq->tdq_sysload++; +#endif +} + +static void +tdq_load_rem(struct tdq *tdq, struct td_sched *ts) +{ + int class; + + THREAD_LOCK_ASSERT(ts->ts_thread, MA_OWNED); + TDQ_LOCK_ASSERT(tdq, MA_OWNED); + class = PRI_BASE(ts->ts_thread->td_pri_class); + if (class != PRI_ITHD && + (ts->ts_thread->td_proc->p_flag & P_NOLOAD) == 0) +#ifdef SMP + tdq->tdq_group->tdg_load--; +#else + tdq->tdq_sysload--; +#endif + KASSERT(tdq->tdq_load != 0, + ("tdq_load_rem: Removing with 0 load on queue %jd", TDQ_ID(tdq))); + tdq->tdq_load--; + CTR1(KTR_SCHED, "load: %d", tdq->tdq_load); + ts->ts_runq = NULL; +} + +#ifdef SMP +static void +sched_smp_tick() +{ + + if (rebalance) { + if (ticks >= bal_tick) + sched_balance(); + if (ticks >= gbal_tick && balance_groups) + sched_balance_groups(); + } +} + +/* + * sched_balance is a simple CPU load balancing algorithm. It operates by + * finding the least loaded and most loaded cpu and equalizing their load + * by migrating some processes. + * + * Dealing only with two CPUs at a time has two advantages. Firstly, most + * installations will only have 2 cpus. Secondly, load balancing too much at + * once can have an unpleasant effect on the system. The scheduler rarely has + * enough information to make perfect decisions. So this algorithm chooses + * simplicity and more gradual effects on load in larger systems. + * + */ +static void +sched_balance(void) +{ + struct tdq_group *high; + struct tdq_group *low; + struct tdq_group *tdg; + int cnt; + int i; + + bal_tick = ticks + (random() % (hz * SCHED_BAL_SECS)); + if (smp_started == 0) + return; + low = high = NULL; + i = random() % (tdg_maxid + 1); + for (cnt = 0; cnt <= tdg_maxid; cnt++) { + tdg = TDQ_GROUP(i); + /* + * Find the CPU with the highest load that has some + * threads to transfer. + */ + if ((high == NULL || tdg->tdg_load > high->tdg_load) + && tdg->tdg_transferable) + high = tdg; + if (low == NULL || tdg->tdg_load < low->tdg_load) + low = tdg; + if (++i > tdg_maxid) + i = 0; + } + if (low != NULL && high != NULL && high != low) + sched_balance_pair(LIST_FIRST(&high->tdg_members), + LIST_FIRST(&low->tdg_members)); +} + +static void +sched_balance_groups(void) +{ + int i; + + gbal_tick = ticks + (random() % (hz * SCHED_BAL_SECS)); + if (smp_started) + for (i = 0; i <= tdg_maxid; i++) + sched_balance_group(TDQ_GROUP(i)); +} + +static void +sched_balance_group(struct tdq_group *tdg) +{ + struct tdq *tdq; + struct tdq *high; + struct tdq *low; + int load; + + if (tdg->tdg_transferable == 0) + return; + low = NULL; + high = NULL; + LIST_FOREACH(tdq, &tdg->tdg_members, tdq_siblings) { + load = tdq->tdq_load; + if (high == NULL || load > high->tdq_load) + high = tdq; + if (low == NULL || load < low->tdq_load) + low = tdq; + } + if (high != NULL && low != NULL && high != low) + sched_balance_pair(high, low); +} + +static void +tdq_lock_pair(struct tdq *one, struct tdq *two) +{ + if (one < two) { + TDQ_LOCK(one); + TDQ_LOCK_FLAGS(two, MTX_DUPOK); + } else { + TDQ_LOCK(two); + TDQ_LOCK_FLAGS(one, MTX_DUPOK); + } +} + +static void +sched_balance_pair(struct tdq *high, struct tdq *low) +{ + int transferable; + int high_load; + int low_load; + int move; + int diff; + int i; + + tdq_lock_pair(high, low); + /* + * If we're transfering within a group we have to use this specific + * tdq's transferable count, otherwise we can steal from other members + * of the group. + */ + if (high->tdq_group == low->tdq_group) { + transferable = high->tdq_transferable; + high_load = high->tdq_load; + low_load = low->tdq_load; + } else { + transferable = high->tdq_group->tdg_transferable; + high_load = high->tdq_group->tdg_load; + low_load = low->tdq_group->tdg_load; + } + /* + * Determine what the imbalance is and then adjust that to how many + * threads we actually have to give up (transferable). + */ + if (transferable != 0) { + diff = high_load - low_load; + move = diff / 2; + if (diff & 0x1) + move++; + move = min(move, transferable); + for (i = 0; i < move; i++) + tdq_move(high, low); + } + TDQ_UNLOCK(high); + TDQ_UNLOCK(low); + return; +} + +static void +tdq_move(struct tdq *from, struct tdq *to) +{ + struct td_sched *ts; + struct tdq *tdq; + int cpu; + + tdq = from; + cpu = TDQ_ID(to); + ts = tdq_steal(tdq, 1); + if (ts == NULL) { + struct tdq_group *tdg; + + tdg = tdq->tdq_group; + LIST_FOREACH(tdq, &tdg->tdg_members, tdq_siblings) { + if (tdq == from || tdq->tdq_transferable == 0) + continue; + ts = tdq_steal(tdq, 1); + break; + } + if (ts == NULL) + return; + } + if (tdq == to) + return; + sched_rem(ts->ts_thread); + ts->ts_cpu = cpu; + ts->ts_thread->td_lock = TDQ_LOCKPTR(to); + tdq_add(to, ts->ts_thread, SRQ_YIELDING); +} + +static int +tdq_idled(struct tdq *tdq) +{ + struct tdq_group *tdg; + struct tdq *steal; + struct td_sched *ts; + struct thread *td; + int highload; + int highcpu; + int load; + int cpu; + + /* We don't want to be preempted while we're iterating over tdqs */ + spinlock_enter(); + tdg = tdq->tdq_group; + /* + * If we're in a cpu group, try and steal threads from another cpu in + * the group before idling. + */ + if (steal_htt && tdg->tdg_cpus > 1 && tdg->tdg_transferable) { + LIST_FOREACH(steal, &tdg->tdg_members, tdq_siblings) { + if (steal == tdq || steal->tdq_transferable == 0) + continue; + TDQ_LOCK(steal); + ts = tdq_steal(steal, 0); + if (ts) + goto steal; + TDQ_UNLOCK(steal); + } + } + for (;;) { + if (steal_busy == 0) + break; + highcpu = 0; + highload = 0; + for (cpu = 0; cpu <= mp_maxid; cpu++) { + if (CPU_ABSENT(cpu)) + continue; + steal = TDQ_CPU(cpu); + load = TDQ_CPU(cpu)->tdq_transferable; + if (load < highload) + continue; + highload = load; + highcpu = cpu; + } + if (highload < 2) + break; + steal = TDQ_CPU(highcpu); + TDQ_LOCK(steal); + if (steal->tdq_transferable > 1 && + (ts = tdq_steal(steal, 1)) != NULL) + goto steal; + TDQ_UNLOCK(steal); + break; + } + spinlock_exit(); + return (1); +steal: + td = ts->ts_thread; + thread_lock(td); + spinlock_exit(); + MPASS(td->td_lock == TDQ_LOCKPTR(steal)); + TDQ_UNLOCK(steal); + sched_rem(td); + ts->ts_cpu = PCPU_GET(cpuid); + thread_lock_block(td); + TDQ_LOCK(tdq); + thread_lock_unblock(td, TDQ_LOCKPTR(tdq)); + tdq_add(tdq, td, SRQ_YIELDING); + mi_switch(SW_VOL, NULL); + TDQ_UNLOCK(tdq); + + return (0); +} + +static void +tdq_notify(struct td_sched *ts) +{ + struct thread *ctd; + struct pcpu *pcpu; + int cpri; + int pri; + int cpu; + + cpu = ts->ts_cpu; + pri = ts->ts_thread->td_priority; + pcpu = pcpu_find(cpu); + ctd = pcpu->pc_curthread; + cpri = ctd->td_priority; + + /* + * If our priority is not better than the current priority there is + * nothing to do. + */ + if (pri > cpri) + return; + /* + * Always IPI idle. + */ + if (cpri > PRI_MIN_IDLE) + goto sendipi; + /* + * If we're realtime or better and there is timeshare or worse running + * send an IPI. + */ + if (pri < PRI_MAX_REALTIME && cpri > PRI_MAX_REALTIME) + goto sendipi; + /* + * Otherwise only IPI if we exceed the threshold. + */ + if (pri > preempt_thresh) + return; +sendipi: + ctd->td_flags |= TDF_NEEDRESCHED; + ipi_selected(1 << cpu, IPI_PREEMPT); +} + +static struct td_sched * +runq_steal_from(struct runq *rq, u_char start) +{ + struct td_sched *ts; + struct rqbits *rqb; + struct rqhead *rqh; + int first; + int bit; + int pri; + int i; + + rqb = &rq->rq_status; + bit = start & (RQB_BPW -1); + pri = 0; + first = 0; +again: + for (i = RQB_WORD(start); i < RQB_LEN; bit = 0, i++) { + if (rqb->rqb_bits[i] == 0) + continue; + if (bit != 0) { + for (pri = bit; pri < RQB_BPW; pri++) + if (rqb->rqb_bits[i] & (1ul << pri)) + break; + if (pri >= RQB_BPW) + continue; + } else + pri = RQB_FFS(rqb->rqb_bits[i]); + pri += (i << RQB_L2BPW); + rqh = &rq->rq_queues[pri]; + TAILQ_FOREACH(ts, rqh, ts_procq) { + if (first && THREAD_CAN_MIGRATE(ts->ts_thread)) + return (ts); + first = 1; + } + } + if (start != 0) { + start = 0; + goto again; + } + + return (NULL); +} + +static struct td_sched * +runq_steal(struct runq *rq) +{ + struct rqhead *rqh; + struct rqbits *rqb; + struct td_sched *ts; + int first; + int word; + int bit; + + first = 0; + rqb = &rq->rq_status; + for (word = 0; word < RQB_LEN; word++) { + if (rqb->rqb_bits[word] == 0) + continue; + for (bit = 0; bit < RQB_BPW; bit++) { + if ((rqb->rqb_bits[word] & (1ul << bit)) == 0) + continue; + rqh = &rq->rq_queues[bit + (word << RQB_L2BPW)]; + TAILQ_FOREACH(ts, rqh, ts_procq) { + if (first && THREAD_CAN_MIGRATE(ts->ts_thread)) + return (ts); + first = 1; + } + } + } + return (NULL); +} + +static struct td_sched * +tdq_steal(struct tdq *tdq, int stealidle) +{ + struct td_sched *ts; + + TDQ_LOCK_ASSERT(tdq, MA_OWNED); + /* + * Steal from next first to try to get a non-interactive task that + * may not have run for a while. + * XXX Need to effect steal order for timeshare threads. + */ + if ((ts = runq_steal(&tdq->tdq_realtime)) != NULL) + return (ts); + if ((ts = runq_steal_from(&tdq->tdq_timeshare, tdq->tdq_ridx)) != NULL) + return (ts); + if (stealidle) + return (runq_steal(&tdq->tdq_idle)); + return (NULL); +} + +static inline struct tdq * +sched_setcpu(struct td_sched *ts, int cpu, int flags) +{ + struct thread *td; + struct tdq *tdq; + int self; + + THREAD_LOCK_ASSERT(ts->ts_thread, MA_OWNED); + + tdq = TDQ_CPU(cpu); + td = ts->ts_thread; + if (td->td_lock == TDQ_LOCKPTR(tdq)) + goto setcpu; +#ifdef notyet + /* + * If the thread isn't running it's lockptr is a + * turnstile or a sleepqueue. We can just lock_set without + * blocking. + */ + if (TD_CAN_RUN(td)) { + TDQ_LOCK(tdq); + thread_lock_set(td, TDQ_LOCKPTR(tdq)); + goto setcpu; + } +#endif + /* + * This is via sched_switch(). We want to lock the tdq but leave + * the thread blocked. We also have to unlock the current cpu's lock + * if we're migrating. + */ + if (flags & SRQ_OURSELF) { + self = PCPU_GET(cpuid); + if (cpu == self) + goto setcpu; + MPASS(td->td_lock == &blocked_lock); + TDQ_UNLOCK(TDQ_CPU(self)); + TDQ_LOCK(tdq); + goto setcpu; + } + /* + * The hard case, migration, we need to block the thread first to + * prevent order reversals with other cpus locks. + */ + thread_lock_block(td); + TDQ_LOCK(tdq); + thread_lock_unblock(td, TDQ_LOCKPTR(tdq)); + +setcpu: + ts->ts_cpu = cpu; + return (tdq); +} + +static int +tdq_lowestpri(void) +{ + struct tdq *tdq; + int lowpri; + int lowcpu; + int lowload; + int load; + int cpu; + int pri; + + lowload = 0; + lowpri = lowcpu = 0; + for (cpu = 0; cpu <= mp_maxid; cpu++) { + if (CPU_ABSENT(cpu)) + continue; + tdq = TDQ_CPU(cpu); + pri = tdq->tdq_lowpri; + load = TDQ_CPU(cpu)->tdq_load; + CTR4(KTR_ULE, + "cpu %d pri %d lowcpu %d lowpri %d", + cpu, pri, lowcpu, lowpri); + if (pri < lowpri) + continue; + if (lowpri && lowpri == pri && load > lowload) + continue; + lowpri = pri; + lowcpu = cpu; + lowload = load; + } + + return (lowcpu); +} + +static int +tdq_lowestload(void) +{ + struct tdq *tdq; + int lowload; + int lowpri; + int lowcpu; + int load; + int cpu; + int pri; + + lowcpu = 0; + lowload = TDQ_CPU(0)->tdq_load; + lowpri = TDQ_CPU(0)->tdq_lowpri; + for (cpu = 1; cpu <= mp_maxid; cpu++) { + if (CPU_ABSENT(cpu)) + continue; + tdq = TDQ_CPU(cpu); + load = tdq->tdq_load; + pri = tdq->tdq_lowpri; + CTR4(KTR_ULE, "cpu %d load %d lowcpu %d lowload %d", + cpu, load, lowcpu, lowload); + if (load > lowload) + continue; + if (load == lowload && pri < lowpri) + continue; + lowcpu = cpu; + lowload = load; + lowpri = pri; + } + + return (lowcpu); +} + +static int +tdq_pickcpu(struct td_sched *ts, int flags) +{ + struct tdq *tdq; + int self; + int pri; + int cpu; + + cpu = self = PCPU_GET(cpuid); + if (smp_started == 0) + return (self); + pri = ts->ts_thread->td_priority; + cpu = ts->ts_cpu; + /* + * Regardless of affinity, if the last cpu is idle send it there. + */ + tdq = TDQ_CPU(cpu); + if (tdq->tdq_lowpri > PRI_MIN_IDLE) { + CTR5(KTR_ULE, + "ts_cpu %d idle, ltick %d ticks %d pri %d curthread %d", + ts->ts_cpu, ts->ts_rltick, ticks, pri, + tdq->tdq_lowpri); + return (ts->ts_cpu); + } + /* + * If we have affinity, try to place it on the cpu we last ran on. + */ + if (SCHED_AFFINITY(ts) && tdq->tdq_lowpri > pri) { + CTR5(KTR_ULE, + "affinity for %d, ltick %d ticks %d pri %d curthread %d", + ts->ts_cpu, ts->ts_rltick, ticks, pri, + tdq->tdq_lowpri); + return (ts->ts_cpu); + } + /* + * Try ourself first; If we're running something lower priority this + * may have some locality with the waking thread and execute faster + * here. + */ + if (tryself) { + /* + * If we're being awoken by an interrupt thread or the waker + * is going right to sleep run here as well. + */ + if ((TDQ_SELF()->tdq_load <= 1) && (flags & (SRQ_YIELDING) || + curthread->td_pri_class == PRI_ITHD)) { + CTR2(KTR_ULE, "tryself load %d flags %d", + TDQ_SELF()->tdq_load, flags); + return (self); + } + } + /* + * Look for an idle group. + */ + CTR1(KTR_ULE, "tdq_idle %X", tdq_idle); + cpu = ffs(tdq_idle); + if (cpu) + return (--cpu); + if (tryselfidle && pri < curthread->td_priority) { + CTR1(KTR_ULE, "tryselfidle %d", + curthread->td_priority); + return (self); + } + /* + * XXX Under heavy load mysql performs way better if you + * serialize the non-running threads on one cpu. This is + * a horrible hack. + */ + if (pick_mysql) + return (0); + /* + * Now search for the cpu running the lowest priority thread with + * the least load. + */ + if (pick_pri) + cpu = tdq_lowestpri(); + else + cpu = tdq_lowestload(); + return (cpu); +} + +#endif /* SMP */ + +/* + * Pick the highest priority task we have and return it. + */ + +static struct td_sched * +tdq_choose(struct tdq *tdq) +{ + struct td_sched *ts; + + TDQ_LOCK_ASSERT(tdq, MA_OWNED); + ts = runq_choose(&tdq->tdq_realtime); + if (ts != NULL) + return (ts); + ts = runq_choose_from(&tdq->tdq_timeshare, tdq->tdq_ridx); + if (ts != NULL) { + KASSERT(ts->ts_thread->td_priority >= PRI_MIN_TIMESHARE, + ("tdq_choose: Invalid priority on timeshare queue %d", + ts->ts_thread->td_priority)); + return (ts); + } + + ts = runq_choose(&tdq->tdq_idle); + if (ts != NULL) { + KASSERT(ts->ts_thread->td_priority >= PRI_MIN_IDLE, + ("tdq_choose: Invalid priority on idle queue %d", + ts->ts_thread->td_priority)); + return (ts); + } + + return (NULL); +} + +static void +tdq_setup(struct tdq *tdq) +{ + + snprintf(tdq->tdq_name, sizeof(tdq->tdq_name), + "sched queue lock %d", (int)TDQ_ID(tdq)); + snprintf(tdq->tdq_runname, sizeof(tdq->tdq_name), + "sched run lock %d", (int)TDQ_ID(tdq)); + mtx_init(&tdq->tdq_lock, tdq->tdq_name, "sched lock", + MTX_SPIN | MTX_RECURSE); + mtx_init(&tdq->tdq_runlock, tdq->tdq_runname, "sched run lock", + MTX_SPIN | MTX_RECURSE); + runq_init(&tdq->tdq_realtime); + runq_init(&tdq->tdq_timeshare); + runq_init(&tdq->tdq_idle); + tdq->tdq_load = 0; +} + +static void +sched_setup(void *dummy) +{ + struct tdq *tdq; +#ifdef SMP + int i; +#endif + + /* + * To avoid divide-by-zero, we set realstathz a dummy value + * in case which sched_clock() called before sched_initticks(). + */ + realstathz = hz; + sched_slice = (realstathz/10); /* ~100ms */ + tickincr = 1 << SCHED_TICK_SHIFT; + +#ifdef SMP + balance_groups = 0; + /* + * Initialize the tdqs. + */ + for (i = 0; i < MAXCPU; i++) { + tdq = &tdq_cpu[i]; + tdq_setup(&tdq_cpu[i]); + } + if (smp_topology == NULL) { + struct tdq_group *tdg; + int cpus; + + for (cpus = 0, i = 0; i < MAXCPU; i++) { + if (CPU_ABSENT(i)) + continue; + tdq = &tdq_cpu[i]; + tdg = &tdq_groups[cpus]; + /* + * Setup a tdq group with one member. + */ + tdq->tdq_transferable = 0; + tdq->tdq_group = tdg; + tdg->tdg_cpus = 1; + tdg->tdg_idlemask = 0; + tdg->tdg_cpumask = tdg->tdg_mask = 1 << i; + tdg->tdg_load = 0; + tdg->tdg_transferable = 0; + LIST_INIT(&tdg->tdg_members); + LIST_INSERT_HEAD(&tdg->tdg_members, tdq, tdq_siblings); + cpus++; + } + tdg_maxid = cpus - 1; + } else { + struct tdq_group *tdg; + struct cpu_group *cg; + int j; + + topology = 1; + for (i = 0; i < smp_topology->ct_count; i++) { + cg = &smp_topology->ct_group[i]; + tdg = &tdq_groups[i]; + /* + * Initialize the group. + */ + tdg->tdg_idlemask = 0; + tdg->tdg_load = 0; + tdg->tdg_transferable = 0; + tdg->tdg_cpus = cg->cg_count; + tdg->tdg_cpumask = cg->cg_mask; + LIST_INIT(&tdg->tdg_members); + /* + * Find all of the group members and add them. + */ + for (j = 0; j < MAXCPU; j++) { + if ((cg->cg_mask & (1 << j)) != 0) { + if (tdg->tdg_mask == 0) + tdg->tdg_mask = 1 << j; + tdq_cpu[j].tdq_transferable = 0; + tdq_cpu[j].tdq_group = tdg; + LIST_INSERT_HEAD(&tdg->tdg_members, + &tdq_cpu[j], tdq_siblings); + } + } + if (tdg->tdg_cpus > 1) + balance_groups = 1; + } + tdg_maxid = smp_topology->ct_count - 1; + } + /* + * Stagger the group and global load balancer so they do not + * interfere with each other. + */ + bal_tick = ticks + hz; + if (balance_groups) + gbal_tick = ticks + (hz / 2); +#else + tdq_setup(TDQ_SELF()); +#endif + tdq = TDQ_SELF(); + TDQ_LOCK(tdq); + tdq_load_add(tdq, &td_sched0); + TDQ_UNLOCK(tdq); +} + +/* ARGSUSED */ +static void +sched_initticks(void *dummy) +{ + int incr; + + realstathz = stathz ? stathz : hz; + sched_slice = (realstathz/10); /* ~100ms */ + + /* + * tickincr is shifted out by 10 to avoid rounding errors due to + * hz not being evenly divisible by stathz on all platforms. + */ + incr = (hz << SCHED_TICK_SHIFT) / realstathz; + /* + * This does not work for values of stathz that are more than + * 1 << SCHED_TICK_SHIFT * hz. In practice this does not happen. + */ + if (incr == 0) + incr = 1; + tickincr = incr; +#ifdef SMP + affinity = SCHED_AFFINITY_DEFAULT; +#endif +} + + +static int +sched_interact_score(struct thread *td) +{ + struct td_sched *ts; + int div; + + ts = td->td_sched; + /* + * The score is only needed if this is likely to be an interactive + * task. Don't go through the expense of computing it if there's + * no chance. + */ + if (sched_interact <= SCHED_INTERACT_HALF && + ts->skg_runtime >= ts->skg_slptime) + return (SCHED_INTERACT_HALF); + + if (ts->skg_runtime > ts->skg_slptime) { + div = max(1, ts->skg_runtime / SCHED_INTERACT_HALF); + return (SCHED_INTERACT_HALF + + (SCHED_INTERACT_HALF - (ts->skg_slptime / div))); + } + if (ts->skg_slptime > ts->skg_runtime) { + div = max(1, ts->skg_slptime / SCHED_INTERACT_HALF); + return (ts->skg_runtime / div); + } + /* runtime == slptime */ + if (ts->skg_runtime) + return (SCHED_INTERACT_HALF); + + /* + * This can happen if slptime and runtime are 0. + */ + return (0); + +} + +/* + * Scale the scheduling priority according to the "interactivity" of this + * process. + */ +static void +sched_priority(struct thread *td) +{ + int score; + int pri; + + if (td->td_pri_class != PRI_TIMESHARE) + return; + /* + * If the score is interactive we place the thread in the realtime + * queue with a priority that is less than kernel and interrupt + * priorities. These threads are not subject to nice restrictions. + * + * Scores greater than this are placed on the normal realtime queue + * where the priority is partially decided by the most recent cpu + * utilization and the rest is decided by nice value. + */ + score = sched_interact_score(td); + if (score < sched_interact) { + pri = PRI_MIN_REALTIME; + pri += ((PRI_MAX_REALTIME - PRI_MIN_REALTIME) / sched_interact) + * score; + KASSERT(pri >= PRI_MIN_REALTIME && pri <= PRI_MAX_REALTIME, + ("sched_priority: invalid interactive priority %d score %d", + pri, score)); + } else { + pri = SCHED_PRI_MIN; + if (td->td_sched->ts_ticks) + pri += SCHED_PRI_TICKS(td->td_sched); + pri += SCHED_PRI_NICE(td->td_proc->p_nice); + KASSERT(pri >= PRI_MIN_TIMESHARE && pri <= PRI_MAX_TIMESHARE, + ("sched_priority: invalid priority %d: nice %d, " + "ticks %d ftick %d ltick %d tick pri %d", + pri, td->td_proc->p_nice, td->td_sched->ts_ticks, + td->td_sched->ts_ftick, td->td_sched->ts_ltick, + SCHED_PRI_TICKS(td->td_sched))); + } + sched_user_prio(td, pri); + + return; +} + +/* + * This routine enforces a maximum limit on the amount of scheduling history + * kept. It is called after either the slptime or runtime is adjusted. + */ +static void +sched_interact_update(struct thread *td) +{ + struct td_sched *ts; + u_int sum; + + ts = td->td_sched; + sum = ts->skg_runtime + ts->skg_slptime; + if (sum < SCHED_SLP_RUN_MAX) + return; + /* + * This only happens from two places: + * 1) We have added an unusual amount of run time from fork_exit. + * 2) We have added an unusual amount of sleep time from sched_sleep(). + */ + if (sum > SCHED_SLP_RUN_MAX * 2) { + if (ts->skg_runtime > ts->skg_slptime) { + ts->skg_runtime = SCHED_SLP_RUN_MAX; + ts->skg_slptime = 1; + } else { + ts->skg_slptime = SCHED_SLP_RUN_MAX; + ts->skg_runtime = 1; + } + return; + } + /* + * If we have exceeded by more than 1/5th then the algorithm below + * will not bring us back into range. Dividing by two here forces + * us into the range of [4/5 * SCHED_INTERACT_MAX, SCHED_INTERACT_MAX] + */ + if (sum > (SCHED_SLP_RUN_MAX / 5) * 6) { + ts->skg_runtime /= 2; + ts->skg_slptime /= 2; + return; + } + ts->skg_runtime = (ts->skg_runtime / 5) * 4; + ts->skg_slptime = (ts->skg_slptime / 5) * 4; +} + +static void +sched_interact_fork(struct thread *td) +{ + int ratio; + int sum; + + sum = td->td_sched->skg_runtime + td->td_sched->skg_slptime; + if (sum > SCHED_SLP_RUN_FORK) { + ratio = sum / SCHED_SLP_RUN_FORK; + td->td_sched->skg_runtime /= ratio; + td->td_sched->skg_slptime /= ratio; + } +} + +/* + * Called from proc0_init() to bootstrap the scheduler. + */ +void +schedinit(void) +{ + + /* + * Set up the scheduler specific parts of proc0. + */ + proc0.p_sched = NULL; /* XXX */ + thread0.td_sched = &td_sched0; + thread0.td_lock = TDQ_LOCKPTR(TDQ_SELF()); + td_sched0.ts_ltick = ticks; + td_sched0.ts_ftick = ticks; + td_sched0.ts_thread = &thread0; +} + +/* + * This is only somewhat accurate since given many processes of the same + * priority they will switch when their slices run out, which will be + * at most sched_slice stathz ticks. + */ +int +sched_rr_interval(void) +{ + + /* Convert sched_slice to hz */ + return (hz/(realstathz/sched_slice)); +} + +static void +sched_pctcpu_update(struct td_sched *ts) +{ + + if (ts->ts_ticks == 0) + return; + if (ticks - (hz / 10) < ts->ts_ltick && + SCHED_TICK_TOTAL(ts) < SCHED_TICK_MAX) + return; + /* + * Adjust counters and watermark for pctcpu calc. + */ + if (ts->ts_ltick > ticks - SCHED_TICK_TARG) + ts->ts_ticks = (ts->ts_ticks / (ticks - ts->ts_ftick)) * + SCHED_TICK_TARG; + else + ts->ts_ticks = 0; + ts->ts_ltick = ticks; + ts->ts_ftick = ts->ts_ltick - SCHED_TICK_TARG; +} + +static void +sched_thread_priority(struct thread *td, u_char prio) +{ + struct td_sched *ts; + + CTR6(KTR_SCHED, "sched_prio: %p(%s) prio %d newprio %d by %p(%s)", + td, td->td_proc->p_comm, td->td_priority, prio, curthread, + curthread->td_proc->p_comm); + ts = td->td_sched; + THREAD_LOCK_ASSERT(td, MA_OWNED); + if (td->td_priority == prio) + return; + + if (TD_ON_RUNQ(td) && prio < td->td_priority) { + /* + * If the priority has been elevated due to priority + * propagation, we may have to move ourselves to a new + * queue. This could be optimized to not re-add in some + * cases. + */ + sched_rem(td); + td->td_priority = prio; + sched_add(td, SRQ_BORROWING); + } else { +#ifdef SMP + struct tdq *tdq; + + tdq = TDQ_CPU(ts->ts_cpu); + if (prio < tdq->tdq_lowpri) + tdq->tdq_lowpri = prio; +#endif + td->td_priority = prio; + } +} + +/* + * Update a thread's priority when it is lent another thread's + * priority. + */ +void +sched_lend_prio(struct thread *td, u_char prio) +{ + + td->td_flags |= TDF_BORROWING; + sched_thread_priority(td, prio); +} + +/* + * Restore a thread's priority when priority propagation is + * over. The prio argument is the minimum priority the thread + * needs to have to satisfy other possible priority lending + * requests. If the thread's regular priority is less + * important than prio, the thread will keep a priority boost + * of prio. + */ +void +sched_unlend_prio(struct thread *td, u_char prio) +{ + u_char base_pri; + + if (td->td_base_pri >= PRI_MIN_TIMESHARE && + td->td_base_pri <= PRI_MAX_TIMESHARE) + base_pri = td->td_user_pri; + else + base_pri = td->td_base_pri; + if (prio >= base_pri) { + td->td_flags &= ~TDF_BORROWING; + sched_thread_priority(td, base_pri); + } else + sched_lend_prio(td, prio); +} + +void +sched_prio(struct thread *td, u_char prio) +{ + u_char oldprio; + + /* First, update the base priority. */ + td->td_base_pri = prio; + + /* + * If the thread is borrowing another thread's priority, don't + * ever lower the priority. + */ + if (td->td_flags & TDF_BORROWING && td->td_priority < prio) + return; + + /* Change the real priority. */ + oldprio = td->td_priority; + sched_thread_priority(td, prio); + + /* + * If the thread is on a turnstile, then let the turnstile update + * its state. + */ + if (TD_ON_LOCK(td) && oldprio != prio) + turnstile_adjust(td, oldprio); +} + +void +sched_user_prio(struct thread *td, u_char prio) +{ + u_char oldprio; + + td->td_base_user_pri = prio; + if (td->td_flags & TDF_UBORROWING && td->td_user_pri <= prio) + return; + oldprio = td->td_user_pri; + td->td_user_pri = prio; + + if (TD_ON_UPILOCK(td) && oldprio != prio) + umtx_pi_adjust(td, oldprio); +} + +void +sched_lend_user_prio(struct thread *td, u_char prio) +{ + u_char oldprio; + + td->td_flags |= TDF_UBORROWING; + + oldprio = td->td_user_pri; + td->td_user_pri = prio; + + if (TD_ON_UPILOCK(td) && oldprio != prio) + umtx_pi_adjust(td, oldprio); +} + +void +sched_unlend_user_prio(struct thread *td, u_char prio) +{ + u_char base_pri; + + base_pri = td->td_base_user_pri; + if (prio >= base_pri) { + td->td_flags &= ~TDF_UBORROWING; + sched_user_prio(td, base_pri); + } else + sched_lend_user_prio(td, prio); +} + +static inline struct mtx * +thread_block_switch(struct thread *td) +{ + struct mtx *lock; + + THREAD_LOCK_ASSERT(td, MA_OWNED); + lock = td->td_lock; + td->td_lock = &blocked_lock; + mtx_unlock_spin(lock); + + return (lock); +} + +static inline void +thread_unblock_switch(struct thread *td, struct mtx *mtx) +{ + atomic_store_rel_ptr((volatile uintptr_t *)&td->td_lock, + (uintptr_t)mtx); +} + +void +sched_switch(struct thread *td, struct thread *newtd, int flags) +{ + struct tdq *tdq; + struct td_sched *ts; + struct mtx *mtx; + int cpuid; + + THREAD_LOCK_ASSERT(td, MA_OWNED); + + cpuid = PCPU_GET(cpuid); + tdq = TDQ_CPU(cpuid); + ts = td->td_sched; +#ifdef SMP + ts->ts_rltick = ticks; +#endif + td->td_lastcpu = td->td_oncpu; + td->td_oncpu = NOCPU; + td->td_flags &= ~TDF_NEEDRESCHED; + td->td_owepreempt = 0; + + /* + * Block the thread so we're free to acquire the correct run queue + * locks. + */ + mtx = thread_lock_block(td); + /* + * If we've been given a thread to execute just add it to the + * run queue rather than directly dispatching. Only KSE does this + * now. This must happen while curthread is blocked. + */ + if (newtd != NULL) { + thread_lock(newtd); + sched_add(newtd, SRQ_YIELDING); + thread_unlock(newtd); + } + TDQ_LOCK(tdq); + /* + * Take care of the outgoing thread's state. + */ + if (TD_IS_IDLETHREAD(td)) { + TD_SET_CAN_RUN(td); + mtx = TDQ_LOCKPTR(tdq); + } else if (TD_IS_RUNNING(td)) { + tdq_load_rem(tdq, ts); + sched_add(td, (flags & SW_PREEMPT) ? + SRQ_OURSELF|SRQ_YIELDING|SRQ_PREEMPTED : + SRQ_OURSELF|SRQ_YIELDING); + /* mtx is no longer the running lock */ + mtx = TDQ_LOCKPTR(TDQ_CPU(ts->ts_cpu)); + /* + * If we migrated in sched_add our lock was dropped and the + * new one was picked up in sched_setcpu(). + */ + if (ts->ts_cpu != cpuid) { + mtx_unlock_spin(mtx); + TDQ_LOCK(tdq); + } + } else + tdq_load_rem(tdq, ts); + /* Drop the extra spinlock nesting acquired in thread_lock_block */ + spinlock_exit(); + TDQ_LOCK_ASSERT(tdq, MA_OWNED | MA_NOTRECURSED); + /* + * Now that we've taken care of the outgoing thread pick a new one + * and switch while we hold the tdq lock. + */ + newtd = choosethread(); + if (td != newtd) { +#ifdef HWPMC_HOOKS + if (PMC_PROC_IS_USING_PMCS(td->td_proc)) + PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_OUT); +#endif + cpu_switch(td, newtd, mtx); + /* + * We may return from cpu_switch on a different cpu. However, + * we always return with td_lock pointing to the current cpu's + * run queue lock. + */ + cpuid = PCPU_GET(cpuid); + tdq = TDQ_CPU(cpuid); + TDQ_LOCKPTR(tdq)->mtx_lock = (uintptr_t)td; +#ifdef HWPMC_HOOKS + if (PMC_PROC_IS_USING_PMCS(td->td_proc)) + PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_IN); +#endif + } else + thread_unblock_switch(td, mtx); +#ifdef SMP + /* We should always get here with the lowest priority td possible */ + tdq->tdq_lowpri = td->td_priority; +#endif + TDQ_LOCK_ASSERT(tdq, MA_OWNED|MA_NOTRECURSED); + MPASS(td->td_lock == TDQ_LOCKPTR(tdq)); + /* + * Switch is complete; transition to the run lock to reduce + * contention on the runqueue lock. + */ + TDQ_RUN_LOCK(tdq); + thread_lock_set(td, TDQ_RUN_LOCKPTR(tdq)); + td->td_oncpu = cpuid; +} + +void +sched_nice(struct proc *p, int nice) +{ + struct thread *td; + + PROC_LOCK_ASSERT(p, MA_OWNED); + PROC_SLOCK_ASSERT(p, MA_OWNED); + + p->p_nice = nice; + FOREACH_THREAD_IN_PROC(p, td) { + thread_lock(td); + sched_priority(td); + sched_prio(td, td->td_base_user_pri); + thread_unlock(td); + } +} + +void +sched_sleep(struct thread *td) +{ + + THREAD_LOCK_ASSERT(td, MA_OWNED); + + td->td_sched->ts_slptime = ticks; +} + +void +sched_wakeup(struct thread *td) +{ + struct td_sched *ts; + int slptime; + + THREAD_LOCK_ASSERT(td, MA_OWNED); + ts = td->td_sched; + /* + * If we slept for more than a tick update our interactivity and + * priority. + */ + slptime = ts->ts_slptime; + ts->ts_slptime = 0; + if (slptime && slptime != ticks) { + u_int hzticks; + + hzticks = (ticks - slptime) << SCHED_TICK_SHIFT; + ts->skg_slptime += hzticks; + sched_interact_update(td); + sched_pctcpu_update(ts); + sched_priority(td); + } + /* Reset the slice value after we sleep. */ + ts->ts_slice = sched_slice; + sched_add(td, SRQ_BORING); +} + +/* + * Penalize the parent for creating a new child and initialize the child's + * priority. + */ +void +sched_fork(struct thread *td, struct thread *child) +{ + THREAD_LOCK_ASSERT(td, MA_OWNED); + sched_fork_thread(td, child); + /* + * Penalize the parent and child for forking. + */ + sched_interact_fork(child); + sched_priority(child); + td->td_sched->skg_runtime += tickincr; + sched_interact_update(td); + sched_priority(td); +} + +void +sched_fork_thread(struct thread *td, struct thread *child) +{ + struct td_sched *ts; + struct td_sched *ts2; + + /* + * Initialize child. + */ + THREAD_LOCK_ASSERT(td, MA_OWNED); + sched_newthread(child); + child->td_lock = TDQ_LOCKPTR(TDQ_SELF()); + ts = td->td_sched; + ts2 = child->td_sched; + ts2->ts_cpu = ts->ts_cpu; + ts2->ts_runq = NULL; + /* + * Grab our parents cpu estimation information and priority. + */ + ts2->ts_ticks = ts->ts_ticks; + ts2->ts_ltick = ts->ts_ltick; + ts2->ts_ftick = ts->ts_ftick; + child->td_user_pri = td->td_user_pri; + child->td_base_user_pri = td->td_base_user_pri; + /* + * And update interactivity score. + */ + ts2->skg_slptime = ts->skg_slptime; + ts2->skg_runtime = ts->skg_runtime; + ts2->ts_slice = 1; /* Attempt to quickly learn interactivity. */ +} + +void +sched_class(struct thread *td, int class) +{ + + THREAD_LOCK_ASSERT(td, MA_OWNED); + if (td->td_pri_class == class) + return; + +#ifdef SMP + /* + * On SMP if we're on the RUNQ we must adjust the transferable + * count because could be changing to or from an interrupt + * class. + */ + if (TD_ON_RUNQ(td)) { + struct tdq *tdq; + + tdq = TDQ_CPU(td->td_sched->ts_cpu); + if (THREAD_CAN_MIGRATE(td)) { + tdq->tdq_transferable--; + tdq->tdq_group->tdg_transferable--; + } + td->td_pri_class = class; + if (THREAD_CAN_MIGRATE(td)) { + tdq->tdq_transferable++; + tdq->tdq_group->tdg_transferable++; + } + } +#endif + td->td_pri_class = class; +} + +/* + * Return some of the child's priority and interactivity to the parent. + */ +void +sched_exit(struct proc *p, struct thread *child) +{ + struct thread *td; + + CTR3(KTR_SCHED, "sched_exit: %p(%s) prio %d", + child, child->td_proc->p_comm, child->td_priority); + + PROC_SLOCK_ASSERT(p, MA_OWNED); + td = FIRST_THREAD_IN_PROC(p); + sched_exit_thread(td, child); +} + +void +sched_exit_thread(struct thread *td, struct thread *child) +{ + + CTR3(KTR_SCHED, "sched_exit_thread: %p(%s) prio %d", + child, child->td_proc->p_comm, child->td_priority); + +#ifdef KSE + /* + * KSE forks and exits so often that this penalty causes short-lived + * threads to always be non-interactive. This causes mozilla to + * crawl under load. + */ + if ((td->td_pflags & TDP_SA) && td->td_proc == child->td_proc) + return; +#endif + /* + * Give the child's runtime to the parent without returning the + * sleep time as a penalty to the parent. This causes shells that + * launch expensive things to mark their children as expensive. + */ + thread_lock(td); + td->td_sched->skg_runtime += child->td_sched->skg_runtime; + sched_interact_update(td); + sched_priority(td); + thread_unlock(td); +} + +void +sched_userret(struct thread *td) +{ + /* + * XXX we cheat slightly on the locking here to avoid locking in + * the usual case. Setting td_priority here is essentially an + * incomplete workaround for not setting it properly elsewhere. + * Now that some interrupt handlers are threads, not setting it + * properly elsewhere can clobber it in the window between setting + * it here and returning to user mode, so don't waste time setting + * it perfectly here. + */ + KASSERT((td->td_flags & TDF_BORROWING) == 0, + ("thread with borrowed priority returning to userland")); + if (td->td_priority != td->td_user_pri) { + thread_lock(td); + td->td_priority = td->td_user_pri; + td->td_base_pri = td->td_user_pri; + thread_unlock(td); + } +} + +void +sched_clock(struct thread *td) +{ + struct tdq *tdq; + struct td_sched *ts; + + THREAD_LOCK_ASSERT(td, MA_OWNED); + tdq = TDQ_SELF(); + /* + * Advance the insert index once for each tick to ensure that all + * threads get a chance to run. + */ + if (tdq->tdq_idx == tdq->tdq_ridx) { + tdq->tdq_idx = (tdq->tdq_idx + 1) % RQ_NQS; + if (TAILQ_EMPTY(&tdq->tdq_timeshare.rq_queues[tdq->tdq_ridx])) + tdq->tdq_ridx = tdq->tdq_idx; + } + ts = td->td_sched; + /* + * We only do slicing code for TIMESHARE threads. + */ + if (td->td_pri_class != PRI_TIMESHARE) + return; + /* + * We used a tick; charge it to the thread so that we can compute our + * interactivity. + */ + td->td_sched->skg_runtime += tickincr; + sched_interact_update(td); + /* + * We used up one time slice. + */ + if (--ts->ts_slice > 0) + return; + /* + * We're out of time, recompute priorities and requeue. + */ + sched_priority(td); + td->td_flags |= TDF_NEEDRESCHED; +} + +int +sched_runnable(void) +{ + struct tdq *tdq; + int load; + + load = 1; + + tdq = TDQ_SELF(); + if ((curthread->td_flags & TDF_IDLETD) != 0) { + if (tdq->tdq_load > 0) + goto out; + } else + if (tdq->tdq_load - 1 > 0) + goto out; + load = 0; +out: + return (load); +} + +struct thread * +sched_choose(void) +{ +#ifdef SMP + struct tdq_group *tdg; +#endif + struct td_sched *ts; + struct tdq *tdq; + + tdq = TDQ_SELF(); + TDQ_LOCK_ASSERT(tdq, MA_OWNED); + ts = tdq_choose(tdq); + if (ts) { + tdq_runq_rem(tdq, ts); + return (ts->ts_thread); + } +#ifdef SMP + /* + * We only set the idled bit when all of the cpus in the group are + * idle. Otherwise we could get into a situation where a thread bounces + * back and forth between two idle cores on seperate physical CPUs. + */ + tdg = tdq->tdq_group; + tdg->tdg_idlemask |= PCPU_GET(cpumask); + if (tdg->tdg_idlemask == tdg->tdg_cpumask) + atomic_set_int(&tdq_idle, tdg->tdg_mask); +#endif + return (PCPU_GET(idlethread)); +} + +static inline void +sched_setpreempt(struct thread *td) +{ + struct thread *ctd; + int cpri; + int pri; + + ctd = curthread; + pri = td->td_priority; + cpri = ctd->td_priority; + if (td->td_priority < ctd->td_priority) + curthread->td_flags |= TDF_NEEDRESCHED; + if (panicstr != NULL || pri >= cpri || cold || TD_IS_INHIBITED(ctd)) + return; + /* + * Always preempt IDLE threads. Otherwise only if the preempting + * thread is an ithread. + */ + if (pri > preempt_thresh && cpri < PRI_MIN_IDLE) + return; + ctd->td_owepreempt = 1; + return; +} + +void +tdq_add(struct tdq *tdq, struct thread *td, int flags) +{ + struct td_sched *ts; + int class; +#ifdef SMP + int cpumask; +#endif + + TDQ_LOCK_ASSERT(tdq, MA_OWNED); + KASSERT((td->td_inhibitors == 0), + ("sched_add: trying to run inhibited thread")); + KASSERT((TD_CAN_RUN(td) || TD_IS_RUNNING(td)), + ("sched_add: bad thread state")); + KASSERT(td->td_proc->p_sflag & PS_INMEM, + ("sched_add: process swapped out")); + + ts = td->td_sched; + class = PRI_BASE(td->td_pri_class); + TD_SET_RUNQ(td); + if (ts->ts_slice == 0) + ts->ts_slice = sched_slice; + /* + * Pick the run queue based on priority. + */ + if (td->td_priority <= PRI_MAX_REALTIME) + ts->ts_runq = &tdq->tdq_realtime; + else if (td->td_priority <= PRI_MAX_TIMESHARE) + ts->ts_runq = &tdq->tdq_timeshare; + else + ts->ts_runq = &tdq->tdq_idle; +#ifdef SMP + cpumask = 1 << ts->ts_cpu; + /* + * If we had been idle, clear our bit in the group and potentially + * the global bitmap. + */ + if ((class != PRI_IDLE && class != PRI_ITHD) && + (tdq->tdq_group->tdg_idlemask & cpumask) != 0) { + /* + * Check to see if our group is unidling, and if so, remove it + * from the global idle mask. + */ + if (tdq->tdq_group->tdg_idlemask == + tdq->tdq_group->tdg_cpumask) + atomic_clear_int(&tdq_idle, tdq->tdq_group->tdg_mask); + /* + * Now remove ourselves from the group specific idle mask. + */ + tdq->tdq_group->tdg_idlemask &= ~cpumask; + } + if (td->td_priority < tdq->tdq_lowpri) + tdq->tdq_lowpri = td->td_priority; +#endif + tdq_runq_add(tdq, ts, flags); + tdq_load_add(tdq, ts); +} + +void +sched_add(struct thread *td, int flags) +{ + struct td_sched *ts; + struct tdq *tdq; +#ifdef SMP + int cpuid; + int cpu; +#endif + CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)", + td, td->td_proc->p_comm, td->td_priority, curthread, + curthread->td_proc->p_comm); + THREAD_LOCK_ASSERT(td, MA_OWNED); + ts = td->td_sched; + /* + * Recalculate the priority before we select the target cpu or + * run-queue. + */ + if (PRI_BASE(td->td_pri_class) == PRI_TIMESHARE) + sched_priority(td); +#ifdef SMP + cpuid = PCPU_GET(cpuid); + /* + * Pick the destination cpu and if it isn't ours transfer to the + * target cpu. + */ + if (td->td_priority <= PRI_MAX_ITHD && THREAD_CAN_MIGRATE(td)) + cpu = cpuid; + else if (!THREAD_CAN_MIGRATE(td)) + cpu = ts->ts_cpu; + else + cpu = tdq_pickcpu(ts, flags); + tdq = sched_setcpu(ts, cpu, flags); + tdq_add(tdq, td, flags); + if (cpu != cpuid) { + tdq_notify(ts); + return; + } +#else + tdq = TDQ_SELF(); + TDQ_LOCK(tdq); + /* + * Now that the thread is moving to the run-queue, set the lock + * to the scheduler's lock. + */ + thread_lock_set(td, TDQ_LOCKPTR(tdq)); + tdq_add(tdq, td, flags); +#endif + if (!(flags & SRQ_YIELDING)) + sched_setpreempt(td); +} + +void +sched_rem(struct thread *td) +{ + struct tdq *tdq; + struct td_sched *ts; + + CTR5(KTR_SCHED, "sched_rem: %p(%s) prio %d by %p(%s)", + td, td->td_proc->p_comm, td->td_priority, curthread, + curthread->td_proc->p_comm); + ts = td->td_sched; + tdq = TDQ_CPU(ts->ts_cpu); + TDQ_LOCK_ASSERT(tdq, MA_OWNED); + MPASS(td->td_lock == TDQ_LOCKPTR(tdq)); + KASSERT(TD_ON_RUNQ(td), + ("sched_rem: thread not on run queue")); + tdq_runq_rem(tdq, ts); + tdq_load_rem(tdq, ts); + TD_SET_CAN_RUN(td); +} + +fixpt_t +sched_pctcpu(struct thread *td) +{ + fixpt_t pctcpu; + struct td_sched *ts; + + pctcpu = 0; + ts = td->td_sched; + if (ts == NULL) + return (0); + + thread_lock(td); + if (ts->ts_ticks) { + int rtick; + + sched_pctcpu_update(ts); + /* How many rtick per second ? */ + rtick = min(SCHED_TICK_HZ(ts) / SCHED_TICK_SECS, hz); + pctcpu = (FSCALE * ((FSCALE * rtick)/hz)) >> FSHIFT; + } + td->td_proc->p_swtime = ts->ts_ltick - ts->ts_ftick; + thread_unlock(td); + + return (pctcpu); +} + +void +sched_bind(struct thread *td, int cpu) +{ + struct td_sched *ts; + + THREAD_LOCK_ASSERT(td, MA_OWNED); + ts = td->td_sched; + if (ts->ts_flags & TSF_BOUND) + sched_unbind(td); + ts->ts_flags |= TSF_BOUND; +#ifdef SMP + sched_pin(); + if (PCPU_GET(cpuid) == cpu) + return; + ts->ts_cpu = cpu; + /* When we return from mi_switch we'll be on the correct cpu. */ + mi_switch(SW_VOL, NULL); +#endif +} + +void +sched_unbind(struct thread *td) +{ + struct td_sched *ts; + + THREAD_LOCK_ASSERT(td, MA_OWNED); + ts = td->td_sched; + if ((ts->ts_flags & TSF_BOUND) == 0) + return; + ts->ts_flags &= ~TSF_BOUND; +#ifdef SMP + sched_unpin(); +#endif +} + +int +sched_is_bound(struct thread *td) +{ + THREAD_LOCK_ASSERT(td, MA_OWNED); + return (td->td_sched->ts_flags & TSF_BOUND); +} + +void +sched_relinquish(struct thread *td) +{ + thread_lock(td); + if (td->td_pri_class == PRI_TIMESHARE) + sched_prio(td, PRI_MAX_TIMESHARE); + SCHED_STAT_INC(switch_relinquish); + mi_switch(SW_VOL, NULL); + thread_unlock(td); +} + +int +sched_load(void) +{ +#ifdef SMP + int total; + int i; + + total = 0; + for (i = 0; i <= tdg_maxid; i++) + total += TDQ_GROUP(i)->tdg_load; + return (total); +#else + return (TDQ_SELF()->tdq_sysload); +#endif +} + +int +sched_sizeof_proc(void) +{ + return (sizeof(struct proc)); +} + +int +sched_sizeof_thread(void) +{ + return (sizeof(struct thread) + sizeof(struct td_sched)); +} + +void +sched_tick(void) +{ + struct td_sched *ts; + +#ifdef SMP + sched_smp_tick(); +#endif + ts = curthread->td_sched; + /* Adjust ticks for pctcpu */ + ts->ts_ticks += 1 << SCHED_TICK_SHIFT; + ts->ts_ltick = ticks; + /* + * Update if we've exceeded our desired tick threshhold by over one + * second. + */ + if (ts->ts_ftick + SCHED_TICK_MAX < ts->ts_ltick) + sched_pctcpu_update(ts); +} + +/* + * The actual idle process. + */ +void +sched_idletd(void *dummy) +{ + struct thread *td; + struct tdq *tdq; + + td = curthread; + tdq = TDQ_SELF(); + mtx_assert(&Giant, MA_NOTOWNED); + /* ULE relies on preemption for idle interruption. */ + for (;;) { +#ifdef SMP + if (tdq_idled(tdq)) + cpu_idle(); +#else + cpu_idle(); +#endif + } +} + +/* + * A CPU is entering for the first time or a thread is exiting. + */ +void +sched_throw(struct thread *td) +{ + struct tdq *tdq; + + tdq = TDQ_SELF(); + /* + * Correct spinlock nesting. The idle thread context that we are + * borrowing was created so that it would start out with a single + * spin lock (sched_lock) held in fork_trampoline(). Since we've + * explicitly acquired locks in this function, the nesting count + * is now 2 rather than 1. Since we are nested, calling + * spinlock_exit() will simply adjust the counts without allowing + * spin lock using code to interrupt us. + */ + if (td == NULL) { + TDQ_LOCK(tdq); + spinlock_exit(); + } else { + /* We need to switch from the run lock to the queue lock. */ + thread_lock_block(td); + TDQ_LOCK(tdq); + thread_lock_unblock(td, TDQ_LOCKPTR(tdq)); + tdq_load_rem(tdq, td->td_sched); + } + KASSERT(curthread->td_md.md_spinlock_count == 1, ("invalid count")); + PCPU_SET(switchtime, cpu_ticks()); + PCPU_SET(switchticks, ticks); + cpu_throw(td, choosethread()); /* doesn't return */ +} + +void +sched_fork_exit(struct thread *td) +{ + struct td_sched *ts; + struct tdq *tdq; + int cpuid; + + /* + * Finish setting up thread glue so that it begins execution in a + * non-nested critical section with the scheduler lock held. + */ + cpuid = PCPU_GET(cpuid); + tdq = TDQ_CPU(cpuid); + ts = td->td_sched; + if (TD_IS_IDLETHREAD(td)) + td->td_lock = TDQ_LOCKPTR(tdq); + MPASS(td->td_lock == TDQ_LOCKPTR(tdq)); + td->td_oncpu = cpuid; + TDQ_LOCKPTR(tdq)->mtx_lock = (uintptr_t)td; + THREAD_LOCK_ASSERT(td, MA_OWNED | MA_NOTRECURSED); +} + +static SYSCTL_NODE(_kern, OID_AUTO, sched, CTLFLAG_RW, 0, "Scheduler"); +SYSCTL_STRING(_kern_sched, OID_AUTO, name, CTLFLAG_RD, "SMP", 0, + "Scheduler name"); +SYSCTL_INT(_kern_sched, OID_AUTO, slice, CTLFLAG_RW, &sched_slice, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, interact, CTLFLAG_RW, &sched_interact, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, tickincr, CTLFLAG_RD, &tickincr, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, realstathz, CTLFLAG_RD, &realstathz, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, preempt_thresh, CTLFLAG_RW, + &preempt_thresh, 0, ""); +#ifdef SMP +SYSCTL_INT(_kern_sched, OID_AUTO, pick_pri, CTLFLAG_RW, &pick_pri, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, pick_mysql, CTLFLAG_RW, &pick_mysql, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, affinity, CTLFLAG_RW, &affinity, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, tryself, CTLFLAG_RW, &tryself, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, tryselfidle, CTLFLAG_RW, + &tryselfidle, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, balance, CTLFLAG_RW, &rebalance, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, steal_htt, CTLFLAG_RW, &steal_htt, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, steal_busy, CTLFLAG_RW, &steal_busy, 0, ""); +SYSCTL_INT(_kern_sched, OID_AUTO, topology, CTLFLAG_RD, &topology, 0, ""); +#endif + +/* ps compat */ +static fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */ +SYSCTL_INT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0, ""); + + +#define KERN_SWITCH_INCLUDE 1 +#include "kern/kern_switch.c"