// SPDX-License-Identifier: GPL-2.0 /* smp.c: Sparc64 SMP support. * * Copyright (C) 1997, 2007, 2008 David S. Miller (davem@davemloft.net) */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "cpumap.h" #include "kernel.h" DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE; cpumask_t cpu_core_map[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = CPU_MASK_NONE }; cpumask_t cpu_core_sib_map[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = CPU_MASK_NONE }; cpumask_t cpu_core_sib_cache_map[NR_CPUS] __read_mostly = { [0 ... NR_CPUS - 1] = CPU_MASK_NONE }; EXPORT_PER_CPU_SYMBOL(cpu_sibling_map); EXPORT_SYMBOL(cpu_core_map); EXPORT_SYMBOL(cpu_core_sib_map); EXPORT_SYMBOL(cpu_core_sib_cache_map); static cpumask_t smp_commenced_mask; static DEFINE_PER_CPU(bool, poke); static bool cpu_poke; void smp_info(struct seq_file *m) { int i; seq_printf(m, "State:\n"); for_each_online_cpu(i) seq_printf(m, "CPU%d:\t\tonline\n", i); } void smp_bogo(struct seq_file *m) { int i; for_each_online_cpu(i) seq_printf(m, "Cpu%dClkTck\t: %016lx\n", i, cpu_data(i).clock_tick); } extern void setup_sparc64_timer(void); static volatile unsigned long callin_flag = 0; void smp_callin(void) { int cpuid = hard_smp_processor_id(); __local_per_cpu_offset = __per_cpu_offset(cpuid); if (tlb_type == hypervisor) sun4v_ktsb_register(); __flush_tlb_all(); setup_sparc64_timer(); if (cheetah_pcache_forced_on) cheetah_enable_pcache(); callin_flag = 1; __asm__ __volatile__("membar #Sync\n\t" "flush %%g6" : : : "memory"); /* Clear this or we will die instantly when we * schedule back to this idler... */ current_thread_info()->new_child = 0; /* Attach to the address space of init_task. */ mmgrab(&init_mm); current->active_mm = &init_mm; /* inform the notifiers about the new cpu */ notify_cpu_starting(cpuid); while (!cpumask_test_cpu(cpuid, &smp_commenced_mask)) rmb(); set_cpu_online(cpuid, true); /* idle thread is expected to have preempt disabled */ preempt_disable(); local_irq_enable(); cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); } void cpu_panic(void) { printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id()); panic("SMP bolixed\n"); } /* This tick register synchronization scheme is taken entirely from * the ia64 port, see arch/ia64/kernel/smpboot.c for details and credit. * * The only change I've made is to rework it so that the master * initiates the synchonization instead of the slave. -DaveM */ #define MASTER 0 #define SLAVE (SMP_CACHE_BYTES/sizeof(unsigned long)) #define NUM_ROUNDS 64 /* magic value */ #define NUM_ITERS 5 /* likewise */ static DEFINE_RAW_SPINLOCK(itc_sync_lock); static unsigned long go[SLAVE + 1]; #define DEBUG_TICK_SYNC 0 static inline long get_delta (long *rt, long *master) { unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0; unsigned long tcenter, t0, t1, tm; unsigned long i; for (i = 0; i < NUM_ITERS; i++) { t0 = tick_ops->get_tick(); go[MASTER] = 1; membar_safe("#StoreLoad"); while (!(tm = go[SLAVE])) rmb(); go[SLAVE] = 0; wmb(); t1 = tick_ops->get_tick(); if (t1 - t0 < best_t1 - best_t0) best_t0 = t0, best_t1 = t1, best_tm = tm; } *rt = best_t1 - best_t0; *master = best_tm - best_t0; /* average best_t0 and best_t1 without overflow: */ tcenter = (best_t0/2 + best_t1/2); if (best_t0 % 2 + best_t1 % 2 == 2) tcenter++; return tcenter - best_tm; } void smp_synchronize_tick_client(void) { long i, delta, adj, adjust_latency = 0, done = 0; unsigned long flags, rt, master_time_stamp; #if DEBUG_TICK_SYNC struct { long rt; /* roundtrip time */ long master; /* master's timestamp */ long diff; /* difference between midpoint and master's timestamp */ long lat; /* estimate of itc adjustment latency */ } t[NUM_ROUNDS]; #endif go[MASTER] = 1; while (go[MASTER]) rmb(); local_irq_save(flags); { for (i = 0; i < NUM_ROUNDS; i++) { delta = get_delta(&rt, &master_time_stamp); if (delta == 0) done = 1; /* let's lock on to this... */ if (!done) { if (i > 0) { adjust_latency += -delta; adj = -delta + adjust_latency/4; } else adj = -delta; tick_ops->add_tick(adj); } #if DEBUG_TICK_SYNC t[i].rt = rt; t[i].master = master_time_stamp; t[i].diff = delta; t[i].lat = adjust_latency/4; #endif } } local_irq_restore(flags); #if DEBUG_TICK_SYNC for (i = 0; i < NUM_ROUNDS; i++) printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n", t[i].rt, t[i].master, t[i].diff, t[i].lat); #endif printk(KERN_INFO "CPU %d: synchronized TICK with master CPU " "(last diff %ld cycles, maxerr %lu cycles)\n", smp_processor_id(), delta, rt); } static void smp_start_sync_tick_client(int cpu); static void smp_synchronize_one_tick(int cpu) { unsigned long flags, i; go[MASTER] = 0; smp_start_sync_tick_client(cpu); /* wait for client to be ready */ while (!go[MASTER]) rmb(); /* now let the client proceed into his loop */ go[MASTER] = 0; membar_safe("#StoreLoad"); raw_spin_lock_irqsave(&itc_sync_lock, flags); { for (i = 0; i < NUM_ROUNDS*NUM_ITERS; i++) { while (!go[MASTER]) rmb(); go[MASTER] = 0; wmb(); go[SLAVE] = tick_ops->get_tick(); membar_safe("#StoreLoad"); } } raw_spin_unlock_irqrestore(&itc_sync_lock, flags); } #if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU) static void ldom_startcpu_cpuid(unsigned int cpu, unsigned long thread_reg, void **descrp) { extern unsigned long sparc64_ttable_tl0; extern unsigned long kern_locked_tte_data; struct hvtramp_descr *hdesc; unsigned long trampoline_ra; struct trap_per_cpu *tb; u64 tte_vaddr, tte_data; unsigned long hv_err; int i; hdesc = kzalloc(sizeof(*hdesc) + (sizeof(struct hvtramp_mapping) * num_kernel_image_mappings - 1), GFP_KERNEL); if (!hdesc) { printk(KERN_ERR "ldom_startcpu_cpuid: Cannot allocate " "hvtramp_descr.\n"); return; } *descrp = hdesc; hdesc->cpu = cpu; hdesc->num_mappings = num_kernel_image_mappings; tb = &trap_block[cpu]; hdesc->fault_info_va = (unsigned long) &tb->fault_info; hdesc->fault_info_pa = kimage_addr_to_ra(&tb->fault_info); hdesc->thread_reg = thread_reg; tte_vaddr = (unsigned long) KERNBASE; tte_data = kern_locked_tte_data; for (i = 0; i < hdesc->num_mappings; i++) { hdesc->maps[i].vaddr = tte_vaddr; hdesc->maps[i].tte = tte_data; tte_vaddr += 0x400000; tte_data += 0x400000; } trampoline_ra = kimage_addr_to_ra(hv_cpu_startup); hv_err = sun4v_cpu_start(cpu, trampoline_ra, kimage_addr_to_ra(&sparc64_ttable_tl0), __pa(hdesc)); if (hv_err) printk(KERN_ERR "ldom_startcpu_cpuid: sun4v_cpu_start() " "gives error %lu\n", hv_err); } #endif extern unsigned long sparc64_cpu_startup; /* The OBP cpu startup callback truncates the 3rd arg cookie to * 32-bits (I think) so to be safe we have it read the pointer * contained here so we work on >4GB machines. -DaveM */ static struct thread_info *cpu_new_thread = NULL; static int smp_boot_one_cpu(unsigned int cpu, struct task_struct *idle) { unsigned long entry = (unsigned long)(&sparc64_cpu_startup); unsigned long cookie = (unsigned long)(&cpu_new_thread); void *descr = NULL; int timeout, ret; callin_flag = 0; cpu_new_thread = task_thread_info(idle); if (tlb_type == hypervisor) { #if defined(CONFIG_SUN_LDOMS) && defined(CONFIG_HOTPLUG_CPU) if (ldom_domaining_enabled) ldom_startcpu_cpuid(cpu, (unsigned long) cpu_new_thread, &descr); else #endif prom_startcpu_cpuid(cpu, entry, cookie); } else { struct device_node *dp = of_find_node_by_cpuid(cpu); prom_startcpu(dp->phandle, entry, cookie); } for (timeout = 0; timeout < 50000; timeout++) { if (callin_flag) break; udelay(100); } if (callin_flag) { ret = 0; } else { printk("Processor %d is stuck.\n", cpu); ret = -ENODEV; } cpu_new_thread = NULL; kfree(descr); return ret; } static void spitfire_xcall_helper(u64 data0, u64 data1, u64 data2, u64 pstate, unsigned long cpu) { u64 result, target; int stuck, tmp; if (this_is_starfire) { /* map to real upaid */ cpu = (((cpu & 0x3c) << 1) | ((cpu & 0x40) >> 4) | (cpu & 0x3)); } target = (cpu << 14) | 0x70; again: /* Ok, this is the real Spitfire Errata #54. * One must read back from a UDB internal register * after writes to the UDB interrupt dispatch, but * before the membar Sync for that write. * So we use the high UDB control register (ASI 0x7f, * ADDR 0x20) for the dummy read. -DaveM */ tmp = 0x40; __asm__ __volatile__( "wrpr %1, %2, %%pstate\n\t" "stxa %4, [%0] %3\n\t" "stxa %5, [%0+%8] %3\n\t" "add %0, %8, %0\n\t" "stxa %6, [%0+%8] %3\n\t" "membar #Sync\n\t" "stxa %%g0, [%7] %3\n\t" "membar #Sync\n\t" "mov 0x20, %%g1\n\t" "ldxa [%%g1] 0x7f, %%g0\n\t" "membar #Sync" : "=r" (tmp) : "r" (pstate), "i" (PSTATE_IE), "i" (ASI_INTR_W), "r" (data0), "r" (data1), "r" (data2), "r" (target), "r" (0x10), "0" (tmp) : "g1"); /* NOTE: PSTATE_IE is still clear. */ stuck = 100000; do { __asm__ __volatile__("ldxa [%%g0] %1, %0" : "=r" (result) : "i" (ASI_INTR_DISPATCH_STAT)); if (result == 0) { __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate)); return; } stuck -= 1; if (stuck == 0) break; } while (result & 0x1); __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate)); if (stuck == 0) { printk("CPU[%d]: mondo stuckage result[%016llx]\n", smp_processor_id(), result); } else { udelay(2); goto again; } } static void spitfire_xcall_deliver(struct trap_per_cpu *tb, int cnt) { u64 *mondo, data0, data1, data2; u16 *cpu_list; u64 pstate; int i; __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate)); cpu_list = __va(tb->cpu_list_pa); mondo = __va(tb->cpu_mondo_block_pa); data0 = mondo[0]; data1 = mondo[1]; data2 = mondo[2]; for (i = 0; i < cnt; i++) spitfire_xcall_helper(data0, data1, data2, pstate, cpu_list[i]); } /* Cheetah now allows to send the whole 64-bytes of data in the interrupt * packet, but we have no use for that. However we do take advantage of * the new pipelining feature (ie. dispatch to multiple cpus simultaneously). */ static void cheetah_xcall_deliver(struct trap_per_cpu *tb, int cnt) { int nack_busy_id, is_jbus, need_more; u64 *mondo, pstate, ver, busy_mask; u16 *cpu_list; cpu_list = __va(tb->cpu_list_pa); mondo = __va(tb->cpu_mondo_block_pa); /* Unfortunately, someone at Sun had the brilliant idea to make the * busy/nack fields hard-coded by ITID number for this Ultra-III * derivative processor. */ __asm__ ("rdpr %%ver, %0" : "=r" (ver)); is_jbus = ((ver >> 32) == __JALAPENO_ID || (ver >> 32) == __SERRANO_ID); __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate)); retry: need_more = 0; __asm__ __volatile__("wrpr %0, %1, %%pstate\n\t" : : "r" (pstate), "i" (PSTATE_IE)); /* Setup the dispatch data registers. */ __asm__ __volatile__("stxa %0, [%3] %6\n\t" "stxa %1, [%4] %6\n\t" "stxa %2, [%5] %6\n\t" "membar #Sync\n\t" : /* no outputs */ : "r" (mondo[0]), "r" (mondo[1]), "r" (mondo[2]), "r" (0x40), "r" (0x50), "r" (0x60), "i" (ASI_INTR_W)); nack_busy_id = 0; busy_mask = 0; { int i; for (i = 0; i < cnt; i++) { u64 target, nr; nr = cpu_list[i]; if (nr == 0xffff) continue; target = (nr << 14) | 0x70; if (is_jbus) { busy_mask |= (0x1UL << (nr * 2)); } else { target |= (nack_busy_id << 24); busy_mask |= (0x1UL << (nack_busy_id * 2)); } __asm__ __volatile__( "stxa %%g0, [%0] %1\n\t" "membar #Sync\n\t" : /* no outputs */ : "r" (target), "i" (ASI_INTR_W)); nack_busy_id++; if (nack_busy_id == 32) { need_more = 1; break; } } } /* Now, poll for completion. */ { u64 dispatch_stat, nack_mask; long stuck; stuck = 100000 * nack_busy_id; nack_mask = busy_mask << 1; do { __asm__ __volatile__("ldxa [%%g0] %1, %0" : "=r" (dispatch_stat) : "i" (ASI_INTR_DISPATCH_STAT)); if (!(dispatch_stat & (busy_mask | nack_mask))) { __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate)); if (unlikely(need_more)) { int i, this_cnt = 0; for (i = 0; i < cnt; i++) { if (cpu_list[i] == 0xffff) continue; cpu_list[i] = 0xffff; this_cnt++; if (this_cnt == 32) break; } goto retry; } return; } if (!--stuck) break; } while (dispatch_stat & busy_mask); __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate)); if (dispatch_stat & busy_mask) { /* Busy bits will not clear, continue instead * of freezing up on this cpu. */ printk("CPU[%d]: mondo stuckage result[%016llx]\n", smp_processor_id(), dispatch_stat); } else { int i, this_busy_nack = 0; /* Delay some random time with interrupts enabled * to prevent deadlock. */ udelay(2 * nack_busy_id); /* Clear out the mask bits for cpus which did not * NACK us. */ for (i = 0; i < cnt; i++) { u64 check_mask, nr; nr = cpu_list[i]; if (nr == 0xffff) continue; if (is_jbus) check_mask = (0x2UL << (2*nr)); else check_mask = (0x2UL << this_busy_nack); if ((dispatch_stat & check_mask) == 0) cpu_list[i] = 0xffff; this_busy_nack += 2; if (this_busy_nack == 64) break; } goto retry; } } } #define CPU_MONDO_COUNTER(cpuid) (cpu_mondo_counter[cpuid]) #define MONDO_USEC_WAIT_MIN 2 #define MONDO_USEC_WAIT_MAX 100 #define MONDO_RETRY_LIMIT 500000 /* Multi-cpu list version. * * Deliver xcalls to 'cnt' number of cpus in 'cpu_list'. * Sometimes not all cpus receive the mondo, requiring us to re-send * the mondo until all cpus have received, or cpus are truly stuck * unable to receive mondo, and we timeout. * Occasionally a target cpu strand is borrowed briefly by hypervisor to * perform guest service, such as PCIe error handling. Consider the * service time, 1 second overall wait is reasonable for 1 cpu. * Here two in-between mondo check wait time are defined: 2 usec for * single cpu quick turn around and up to 100usec for large cpu count. * Deliver mondo to large number of cpus could take longer, we adjusts * the retry count as long as target cpus are making forward progress. */ static void hypervisor_xcall_deliver(struct trap_per_cpu *tb, int cnt) { int this_cpu, tot_cpus, prev_sent, i, rem; int usec_wait, retries, tot_retries; u16 first_cpu = 0xffff; unsigned long xc_rcvd = 0; unsigned long status; int ecpuerror_id = 0; int enocpu_id = 0; u16 *cpu_list; u16 cpu; this_cpu = smp_processor_id(); cpu_list = __va(tb->cpu_list_pa); usec_wait = cnt * MONDO_USEC_WAIT_MIN; if (usec_wait > MONDO_USEC_WAIT_MAX) usec_wait = MONDO_USEC_WAIT_MAX; retries = tot_retries = 0; tot_cpus = cnt; prev_sent = 0; do { int n_sent, mondo_delivered, target_cpu_busy; status = sun4v_cpu_mondo_send(cnt, tb->cpu_list_pa, tb->cpu_mondo_block_pa); /* HV_EOK means all cpus received the xcall, we're done. */ if (likely(status == HV_EOK)) goto xcall_done; /* If not these non-fatal errors, panic */ if (unlikely((status != HV_EWOULDBLOCK) && (status != HV_ECPUERROR) && (status != HV_ENOCPU))) goto fatal_errors; /* First, see if we made any forward progress. * * Go through the cpu_list, count the target cpus that have * received our mondo (n_sent), and those that did not (rem). * Re-pack cpu_list with the cpus remain to be retried in the * front - this simplifies tracking the truly stalled cpus. * * The hypervisor indicates successful sends by setting * cpu list entries to the value 0xffff. * * EWOULDBLOCK means some target cpus did not receive the * mondo and retry usually helps. * * ECPUERROR means at least one target cpu is in error state, * it's usually safe to skip the faulty cpu and retry. * * ENOCPU means one of the target cpu doesn't belong to the * domain, perhaps offlined which is unexpected, but not * fatal and it's okay to skip the offlined cpu. */ rem = 0; n_sent = 0; for (i = 0; i < cnt; i++) { cpu = cpu_list[i]; if (likely(cpu == 0xffff)) { n_sent++; } else if ((status == HV_ECPUERROR) && (sun4v_cpu_state(cpu) == HV_CPU_STATE_ERROR)) { ecpuerror_id = cpu + 1; } else if (status == HV_ENOCPU && !cpu_online(cpu)) { enocpu_id = cpu + 1; } else { cpu_list[rem++] = cpu; } } /* No cpu remained, we're done. */ if (rem == 0) break; /* Otherwise, update the cpu count for retry. */ cnt = rem; /* Record the overall number of mondos received by the * first of the remaining cpus. */ if (first_cpu != cpu_list[0]) { first_cpu = cpu_list[0]; xc_rcvd = CPU_MONDO_COUNTER(first_cpu); } /* Was any mondo delivered successfully? */ mondo_delivered = (n_sent > prev_sent); prev_sent = n_sent; /* or, was any target cpu busy processing other mondos? */ target_cpu_busy = (xc_rcvd < CPU_MONDO_COUNTER(first_cpu)); xc_rcvd = CPU_MONDO_COUNTER(first_cpu); /* Retry count is for no progress. If we're making progress, * reset the retry count. */ if (likely(mondo_delivered || target_cpu_busy)) { tot_retries += retries; retries = 0; } else if (unlikely(retries > MONDO_RETRY_LIMIT)) { goto fatal_mondo_timeout; } /* Delay a little bit to let other cpus catch up on * their cpu mondo queue work. */ if (!mondo_delivered) udelay(usec_wait); retries++; } while (1); xcall_done: if (unlikely(ecpuerror_id > 0)) { pr_crit("CPU[%d]: SUN4V mondo cpu error, target cpu(%d) was in error state\n", this_cpu, ecpuerror_id - 1); } else if (unlikely(enocpu_id > 0)) { pr_crit("CPU[%d]: SUN4V mondo cpu error, target cpu(%d) does not belong to the domain\n", this_cpu, enocpu_id - 1); } return; fatal_errors: /* fatal errors include bad alignment, etc */ pr_crit("CPU[%d]: Args were cnt(%d) cpulist_pa(%lx) mondo_block_pa(%lx)\n", this_cpu, tot_cpus, tb->cpu_list_pa, tb->cpu_mondo_block_pa); panic("Unexpected SUN4V mondo error %lu\n", status); fatal_mondo_timeout: /* some cpus being non-responsive to the cpu mondo */ pr_crit("CPU[%d]: SUN4V mondo timeout, cpu(%d) made no forward progress after %d retries. Total target cpus(%d).\n", this_cpu, first_cpu, (tot_retries + retries), tot_cpus); panic("SUN4V mondo timeout panic\n"); } static void (*xcall_deliver_impl)(struct trap_per_cpu *, int); static void xcall_deliver(u64 data0, u64 data1, u64 data2, const cpumask_t *mask) { struct trap_per_cpu *tb; int this_cpu, i, cnt; unsigned long flags; u16 *cpu_list; u64 *mondo; /* We have to do this whole thing with interrupts fully disabled. * Otherwise if we send an xcall from interrupt context it will * corrupt both our mondo block and cpu list state. * * One consequence of this is that we cannot use timeout mechanisms * that depend upon interrupts being delivered locally. So, for * example, we cannot sample jiffies and expect it to advance. * * Fortunately, udelay() uses %stick/%tick so we can use that. */ local_irq_save(flags); this_cpu = smp_processor_id(); tb = &trap_block[this_cpu]; mondo = __va(tb->cpu_mondo_block_pa); mondo[0] = data0; mondo[1] = data1; mondo[2] = data2; wmb(); cpu_list = __va(tb->cpu_list_pa); /* Setup the initial cpu list. */ cnt = 0; for_each_cpu(i, mask) { if (i == this_cpu || !cpu_online(i)) continue; cpu_list[cnt++] = i; } if (cnt) xcall_deliver_impl(tb, cnt); local_irq_restore(flags); } /* Send cross call to all processors mentioned in MASK_P * except self. Really, there are only two cases currently, * "cpu_online_mask" and "mm_cpumask(mm)". */ static void smp_cross_call_masked(unsigned long *func, u32 ctx, u64 data1, u64 data2, const cpumask_t *mask) { u64 data0 = (((u64)ctx)<<32 | (((u64)func) & 0xffffffff)); xcall_deliver(data0, data1, data2, mask); } /* Send cross call to all processors except self. */ static void smp_cross_call(unsigned long *func, u32 ctx, u64 data1, u64 data2) { smp_cross_call_masked(func, ctx, data1, data2, cpu_online_mask); } extern unsigned long xcall_sync_tick; static void smp_start_sync_tick_client(int cpu) { xcall_deliver((u64) &xcall_sync_tick, 0, 0, cpumask_of(cpu)); } extern unsigned long xcall_call_function; void arch_send_call_function_ipi_mask(const struct cpumask *mask) { xcall_deliver((u64) &xcall_call_function, 0, 0, mask); } extern unsigned long xcall_call_function_single; void arch_send_call_function_single_ipi(int cpu) { xcall_deliver((u64) &xcall_call_function_single, 0, 0, cpumask_of(cpu)); } void __irq_entry smp_call_function_client(int irq, struct pt_regs *regs) { clear_softint(1 << irq); irq_enter(); generic_smp_call_function_interrupt(); irq_exit(); } void __irq_entry smp_call_function_single_client(int irq, struct pt_regs *regs) { clear_softint(1 << irq); irq_enter(); generic_smp_call_function_single_interrupt(); irq_exit(); } static void tsb_sync(void *info) { struct trap_per_cpu *tp = &trap_block[raw_smp_processor_id()]; struct mm_struct *mm = info; /* It is not valid to test "current->active_mm == mm" here. * * The value of "current" is not changed atomically with * switch_mm(). But that's OK, we just need to check the * current cpu's trap block PGD physical address. */ if (tp->pgd_paddr == __pa(mm->pgd)) tsb_context_switch(mm); } void smp_tsb_sync(struct mm_struct *mm) { smp_call_function_many(mm_cpumask(mm), tsb_sync, mm, 1); } extern unsigned long xcall_flush_tlb_mm; extern unsigned long xcall_flush_tlb_page; extern unsigned long xcall_flush_tlb_kernel_range; extern unsigned long xcall_fetch_glob_regs; extern unsigned long xcall_fetch_glob_pmu; extern unsigned long xcall_fetch_glob_pmu_n4; extern unsigned long xcall_receive_signal; extern unsigned long xcall_new_mmu_context_version; #ifdef CONFIG_KGDB extern unsigned long xcall_kgdb_capture; #endif #ifdef DCACHE_ALIASING_POSSIBLE extern unsigned long xcall_flush_dcache_page_cheetah; #endif extern unsigned long xcall_flush_dcache_page_spitfire; static inline void __local_flush_dcache_page(struct page *page) { #ifdef DCACHE_ALIASING_POSSIBLE __flush_dcache_page(page_address(page), ((tlb_type == spitfire) && page_mapping_file(page) != NULL)); #else if (page_mapping_file(page) != NULL && tlb_type == spitfire) __flush_icache_page(__pa(page_address(page))); #endif } void smp_flush_dcache_page_impl(struct page *page, int cpu) { int this_cpu; if (tlb_type == hypervisor) return; #ifdef CONFIG_DEBUG_DCFLUSH atomic_inc(&dcpage_flushes); #endif this_cpu = get_cpu(); if (cpu == this_cpu) { __local_flush_dcache_page(page); } else if (cpu_online(cpu)) { void *pg_addr = page_address(page); u64 data0 = 0; if (tlb_type == spitfire) { data0 = ((u64)&xcall_flush_dcache_page_spitfire); if (page_mapping_file(page) != NULL) data0 |= ((u64)1 << 32); } else if (tlb_type == cheetah || tlb_type == cheetah_plus) { #ifdef DCACHE_ALIASING_POSSIBLE data0 = ((u64)&xcall_flush_dcache_page_cheetah); #endif } if (data0) { xcall_deliver(data0, __pa(pg_addr), (u64) pg_addr, cpumask_of(cpu)); #ifdef CONFIG_DEBUG_DCFLUSH atomic_inc(&dcpage_flushes_xcall); #endif } } put_cpu(); } void flush_dcache_page_all(struct mm_struct *mm, struct page *page) { void *pg_addr; u64 data0; if (tlb_type == hypervisor) return; preempt_disable(); #ifdef CONFIG_DEBUG_DCFLUSH atomic_inc(&dcpage_flushes); #endif data0 = 0; pg_addr = page_address(page); if (tlb_type == spitfire) { data0 = ((u64)&xcall_flush_dcache_page_spitfire); if (page_mapping_file(page) != NULL) data0 |= ((u64)1 << 32); } else if (tlb_type == cheetah || tlb_type == cheetah_plus) { #ifdef DCACHE_ALIASING_POSSIBLE data0 = ((u64)&xcall_flush_dcache_page_cheetah); #endif } if (data0) { xcall_deliver(data0, __pa(pg_addr), (u64) pg_addr, cpu_online_mask); #ifdef CONFIG_DEBUG_DCFLUSH atomic_inc(&dcpage_flushes_xcall); #endif } __local_flush_dcache_page(page); preempt_enable(); } #ifdef CONFIG_KGDB void kgdb_roundup_cpus(unsigned long flags) { smp_cross_call(&xcall_kgdb_capture, 0, 0, 0); } #endif void smp_fetch_global_regs(void) { smp_cross_call(&xcall_fetch_glob_regs, 0, 0, 0); } void smp_fetch_global_pmu(void) { if (tlb_type == hypervisor && sun4v_chip_type >= SUN4V_CHIP_NIAGARA4) smp_cross_call(&xcall_fetch_glob_pmu_n4, 0, 0, 0); else smp_cross_call(&xcall_fetch_glob_pmu, 0, 0, 0); } /* We know that the window frames of the user have been flushed * to the stack before we get here because all callers of us * are flush_tlb_*() routines, and these run after flush_cache_*() * which performs the flushw. * * The SMP TLB coherency scheme we use works as follows: * * 1) mm->cpu_vm_mask is a bit mask of which cpus an address * space has (potentially) executed on, this is the heuristic * we use to avoid doing cross calls. * * Also, for flushing from kswapd and also for clones, we * use cpu_vm_mask as the list of cpus to make run the TLB. * * 2) TLB context numbers are shared globally across all processors * in the system, this allows us to play several games to avoid * cross calls. * * One invariant is that when a cpu switches to a process, and * that processes tsk->active_mm->cpu_vm_mask does not have the * current cpu's bit set, that tlb context is flushed locally. * * If the address space is non-shared (ie. mm->count == 1) we avoid * cross calls when we want to flush the currently running process's * tlb state. This is done by clearing all cpu bits except the current * processor's in current->mm->cpu_vm_mask and performing the * flush locally only. This will force any subsequent cpus which run * this task to flush the context from the local tlb if the process * migrates to another cpu (again). * * 3) For shared address spaces (threads) and swapping we bite the * bullet for most cases and perform the cross call (but only to * the cpus listed in cpu_vm_mask). * * The performance gain from "optimizing" away the cross call for threads is * questionable (in theory the big win for threads is the massive sharing of * address space state across processors). */ /* This currently is only used by the hugetlb arch pre-fault * hook on UltraSPARC-III+ and later when changing the pagesize * bits of the context register for an address space. */ void smp_flush_tlb_mm(struct mm_struct *mm) { u32 ctx = CTX_HWBITS(mm->context); int cpu = get_cpu(); if (atomic_read(&mm->mm_users) == 1) { cpumask_copy(mm_cpumask(mm), cpumask_of(cpu)); goto local_flush_and_out; } smp_cross_call_masked(&xcall_flush_tlb_mm, ctx, 0, 0, mm_cpumask(mm)); local_flush_and_out: __flush_tlb_mm(ctx, SECONDARY_CONTEXT); put_cpu(); } struct tlb_pending_info { unsigned long ctx; unsigned long nr; unsigned long *vaddrs; }; static void tlb_pending_func(void *info) { struct tlb_pending_info *t = info; __flush_tlb_pending(t->ctx, t->nr, t->vaddrs); } void smp_flush_tlb_pending(struct mm_struct *mm, unsigned long nr, unsigned long *vaddrs) { u32 ctx = CTX_HWBITS(mm->context); struct tlb_pending_info info; int cpu = get_cpu(); info.ctx = ctx; info.nr = nr; info.vaddrs = vaddrs; if (mm == current->mm && atomic_read(&mm->mm_users) == 1) cpumask_copy(mm_cpumask(mm), cpumask_of(cpu)); else smp_call_function_many(mm_cpumask(mm), tlb_pending_func, &info, 1); __flush_tlb_pending(ctx, nr, vaddrs); put_cpu(); } void smp_flush_tlb_page(struct mm_struct *mm, unsigned long vaddr) { unsigned long context = CTX_HWBITS(mm->context); int cpu = get_cpu(); if (mm == current->mm && atomic_read(&mm->mm_users) == 1) cpumask_copy(mm_cpumask(mm), cpumask_of(cpu)); else smp_cross_call_masked(&xcall_flush_tlb_page, context, vaddr, 0, mm_cpumask(mm)); __flush_tlb_page(context, vaddr); put_cpu(); } void smp_flush_tlb_kernel_range(unsigned long start, unsigned long end) { start &= PAGE_MASK; end = PAGE_ALIGN(end); if (start != end) { smp_cross_call(&xcall_flush_tlb_kernel_range, 0, start, end); __flush_tlb_kernel_range(start, end); } } /* CPU capture. */ /* #define CAPTURE_DEBUG */ extern unsigned long xcall_capture; static atomic_t smp_capture_depth = ATOMIC_INIT(0); static atomic_t smp_capture_registry = ATOMIC_INIT(0); static unsigned long penguins_are_doing_time; void smp_capture(void) { int result = atomic_add_return(1, &smp_capture_depth); if (result == 1) { int ncpus = num_online_cpus(); #ifdef CAPTURE_DEBUG printk("CPU[%d]: Sending penguins to jail...", smp_processor_id()); #endif penguins_are_doing_time = 1; atomic_inc(&smp_capture_registry); smp_cross_call(&xcall_capture, 0, 0, 0); while (atomic_read(&smp_capture_registry) != ncpus) rmb(); #ifdef CAPTURE_DEBUG printk("done\n"); #endif } } void smp_release(void) { if (atomic_dec_and_test(&smp_capture_depth)) { #ifdef CAPTURE_DEBUG printk("CPU[%d]: Giving pardon to " "imprisoned penguins\n", smp_processor_id()); #endif penguins_are_doing_time = 0; membar_safe("#StoreLoad"); atomic_dec(&smp_capture_registry); } } /* Imprisoned penguins run with %pil == PIL_NORMAL_MAX, but PSTATE_IE * set, so they can service tlb flush xcalls... */ extern void prom_world(int); void __irq_entry smp_penguin_jailcell(int irq, struct pt_regs *regs) { clear_softint(1 << irq); preempt_disable(); __asm__ __volatile__("flushw"); prom_world(1); atomic_inc(&smp_capture_registry); membar_safe("#StoreLoad"); while (penguins_are_doing_time) rmb(); atomic_dec(&smp_capture_registry); prom_world(0); preempt_enable(); } /* /proc/profile writes can call this, don't __init it please. */ int setup_profiling_timer(unsigned int multiplier) { return -EINVAL; } void __init smp_prepare_cpus(unsigned int max_cpus) { } void smp_prepare_boot_cpu(void) { } void __init smp_setup_processor_id(void) { if (tlb_type == spitfire) xcall_deliver_impl = spitfire_xcall_deliver; else if (tlb_type == cheetah || tlb_type == cheetah_plus) xcall_deliver_impl = cheetah_xcall_deliver; else xcall_deliver_impl = hypervisor_xcall_deliver; } void __init smp_fill_in_cpu_possible_map(void) { int possible_cpus = num_possible_cpus(); int i; if (possible_cpus > nr_cpu_ids) possible_cpus = nr_cpu_ids; for (i = 0; i < possible_cpus; i++) set_cpu_possible(i, true); for (; i < NR_CPUS; i++) set_cpu_possible(i, false); } void smp_fill_in_sib_core_maps(void) { unsigned int i; for_each_present_cpu(i) { unsigned int j; cpumask_clear(&cpu_core_map[i]); if (cpu_data(i).core_id == 0) { cpumask_set_cpu(i, &cpu_core_map[i]); continue; } for_each_present_cpu(j) { if (cpu_data(i).core_id == cpu_data(j).core_id) cpumask_set_cpu(j, &cpu_core_map[i]); } } for_each_present_cpu(i) { unsigned int j; for_each_present_cpu(j) { if (cpu_data(i).max_cache_id == cpu_data(j).max_cache_id) cpumask_set_cpu(j, &cpu_core_sib_cache_map[i]); if (cpu_data(i).sock_id == cpu_data(j).sock_id) cpumask_set_cpu(j, &cpu_core_sib_map[i]); } } for_each_present_cpu(i) { unsigned int j; cpumask_clear(&per_cpu(cpu_sibling_map, i)); if (cpu_data(i).proc_id == -1) { cpumask_set_cpu(i, &per_cpu(cpu_sibling_map, i)); continue; } for_each_present_cpu(j) { if (cpu_data(i).proc_id == cpu_data(j).proc_id) cpumask_set_cpu(j, &per_cpu(cpu_sibling_map, i)); } } } int __cpu_up(unsigned int cpu, struct task_struct *tidle) { int ret = smp_boot_one_cpu(cpu, tidle); if (!ret) { cpumask_set_cpu(cpu, &smp_commenced_mask); while (!cpu_online(cpu)) mb(); if (!cpu_online(cpu)) { ret = -ENODEV; } else { /* On SUN4V, writes to %tick and %stick are * not allowed. */ if (tlb_type != hypervisor) smp_synchronize_one_tick(cpu); } } return ret; } #ifdef CONFIG_HOTPLUG_CPU void cpu_play_dead(void) { int cpu = smp_processor_id(); unsigned long pstate; idle_task_exit(); if (tlb_type == hypervisor) { struct trap_per_cpu *tb = &trap_block[cpu]; sun4v_cpu_qconf(HV_CPU_QUEUE_CPU_MONDO, tb->cpu_mondo_pa, 0); sun4v_cpu_qconf(HV_CPU_QUEUE_DEVICE_MONDO, tb->dev_mondo_pa, 0); sun4v_cpu_qconf(HV_CPU_QUEUE_RES_ERROR, tb->resum_mondo_pa, 0); sun4v_cpu_qconf(HV_CPU_QUEUE_NONRES_ERROR, tb->nonresum_mondo_pa, 0); } cpumask_clear_cpu(cpu, &smp_commenced_mask); membar_safe("#Sync"); local_irq_disable(); __asm__ __volatile__( "rdpr %%pstate, %0\n\t" "wrpr %0, %1, %%pstate" : "=r" (pstate) : "i" (PSTATE_IE)); while (1) barrier(); } int __cpu_disable(void) { int cpu = smp_processor_id(); cpuinfo_sparc *c; int i; for_each_cpu(i, &cpu_core_map[cpu]) cpumask_clear_cpu(cpu, &cpu_core_map[i]); cpumask_clear(&cpu_core_map[cpu]); for_each_cpu(i, &per_cpu(cpu_sibling_map, cpu)) cpumask_clear_cpu(cpu, &per_cpu(cpu_sibling_map, i)); cpumask_clear(&per_cpu(cpu_sibling_map, cpu)); c = &cpu_data(cpu); c->core_id = 0; c->proc_id = -1; smp_wmb(); /* Make sure no interrupts point to this cpu. */ fixup_irqs(); local_irq_enable(); mdelay(1); local_irq_disable(); set_cpu_online(cpu, false); cpu_map_rebuild(); return 0; } void __cpu_die(unsigned int cpu) { int i; for (i = 0; i < 100; i++) { smp_rmb(); if (!cpumask_test_cpu(cpu, &smp_commenced_mask)) break; msleep(100); } if (cpumask_test_cpu(cpu, &smp_commenced_mask)) { printk(KERN_ERR "CPU %u didn't die...\n", cpu); } else { #if defined(CONFIG_SUN_LDOMS) unsigned long hv_err; int limit = 100; do { hv_err = sun4v_cpu_stop(cpu); if (hv_err == HV_EOK) { set_cpu_present(cpu, false); break; } } while (--limit > 0); if (limit <= 0) { printk(KERN_ERR "sun4v_cpu_stop() fails err=%lu\n", hv_err); } #endif } } #endif void __init smp_cpus_done(unsigned int max_cpus) { } static void send_cpu_ipi(int cpu) { xcall_deliver((u64) &xcall_receive_signal, 0, 0, cpumask_of(cpu)); } void scheduler_poke(void) { if (!cpu_poke) return; if (!__this_cpu_read(poke)) return; __this_cpu_write(poke, false); set_softint(1 << PIL_SMP_RECEIVE_SIGNAL); } static unsigned long send_cpu_poke(int cpu) { unsigned long hv_err; per_cpu(poke, cpu) = true; hv_err = sun4v_cpu_poke(cpu); if (hv_err != HV_EOK) { per_cpu(poke, cpu) = false; pr_err_ratelimited("%s: sun4v_cpu_poke() fails err=%lu\n", __func__, hv_err); } return hv_err; } void smp_send_reschedule(int cpu) { if (cpu == smp_processor_id()) { WARN_ON_ONCE(preemptible()); set_softint(1 << PIL_SMP_RECEIVE_SIGNAL); return; } /* Use cpu poke to resume idle cpu if supported. */ if (cpu_poke && idle_cpu(cpu)) { unsigned long ret; ret = send_cpu_poke(cpu); if (ret == HV_EOK) return; } /* Use IPI in following cases: * - cpu poke not supported * - cpu not idle * - send_cpu_poke() returns with error */ send_cpu_ipi(cpu); } void smp_init_cpu_poke(void) { unsigned long major; unsigned long minor; int ret; if (tlb_type != hypervisor) return; ret = sun4v_hvapi_get(HV_GRP_CORE, &major, &minor); if (ret) { pr_debug("HV_GRP_CORE is not registered\n"); return; } if (major == 1 && minor >= 6) { /* CPU POKE is registered. */ cpu_poke = true; return; } pr_debug("CPU_POKE not supported\n"); } void __irq_entry smp_receive_signal_client(int irq, struct pt_regs *regs) { clear_softint(1 << irq); scheduler_ipi(); } static void stop_this_cpu(void *dummy) { set_cpu_online(smp_processor_id(), false); prom_stopself(); } void smp_send_stop(void) { int cpu; if (tlb_type == hypervisor) { int this_cpu = smp_processor_id(); #ifdef CONFIG_SERIAL_SUNHV sunhv_migrate_hvcons_irq(this_cpu); #endif for_each_online_cpu(cpu) { if (cpu == this_cpu) continue; set_cpu_online(cpu, false); #ifdef CONFIG_SUN_LDOMS if (ldom_domaining_enabled) { unsigned long hv_err; hv_err = sun4v_cpu_stop(cpu); if (hv_err) printk(KERN_ERR "sun4v_cpu_stop() " "failed err=%lu\n", hv_err); } else #endif prom_stopcpu_cpuid(cpu); } } else smp_call_function(stop_this_cpu, NULL, 0); } /** * pcpu_alloc_bootmem - NUMA friendly alloc_bootmem wrapper for percpu * @cpu: cpu to allocate for * @size: size allocation in bytes * @align: alignment * * Allocate @size bytes aligned at @align for cpu @cpu. This wrapper * does the right thing for NUMA regardless of the current * configuration. * * RETURNS: * Pointer to the allocated area on success, NULL on failure. */ static void * __init pcpu_alloc_bootmem(unsigned int cpu, size_t size, size_t align) { const unsigned long goal = __pa(MAX_DMA_ADDRESS); #ifdef CONFIG_NEED_MULTIPLE_NODES int node = cpu_to_node(cpu); void *ptr; if (!node_online(node) || !NODE_DATA(node)) { ptr = memblock_alloc_from(size, align, goal); pr_info("cpu %d has no node %d or node-local memory\n", cpu, node); pr_debug("per cpu data for cpu%d %lu bytes at %016lx\n", cpu, size, __pa(ptr)); } else { ptr = memblock_alloc_try_nid(size, align, goal, BOOTMEM_ALLOC_ACCESSIBLE, node); pr_debug("per cpu data for cpu%d %lu bytes on node%d at " "%016lx\n", cpu, size, node, __pa(ptr)); } return ptr; #else return memblock_alloc_from(size, align, goal); #endif } static void __init pcpu_free_bootmem(void *ptr, size_t size) { memblock_free(__pa(ptr), size); } static int __init pcpu_cpu_distance(unsigned int from, unsigned int to) { if (cpu_to_node(from) == cpu_to_node(to)) return LOCAL_DISTANCE; else return REMOTE_DISTANCE; } static void __init pcpu_populate_pte(unsigned long addr) { pgd_t *pgd = pgd_offset_k(addr); pud_t *pud; pmd_t *pmd; if (pgd_none(*pgd)) { pud_t *new; new = memblock_alloc_from(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE); pgd_populate(&init_mm, pgd, new); } pud = pud_offset(pgd, addr); if (pud_none(*pud)) { pmd_t *new; new = memblock_alloc_from(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE); pud_populate(&init_mm, pud, new); } pmd = pmd_offset(pud, addr); if (!pmd_present(*pmd)) { pte_t *new; new = memblock_alloc_from(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE); pmd_populate_kernel(&init_mm, pmd, new); } } void __init setup_per_cpu_areas(void) { unsigned long delta; unsigned int cpu; int rc = -EINVAL; if (pcpu_chosen_fc != PCPU_FC_PAGE) { rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE, PERCPU_DYNAMIC_RESERVE, 4 << 20, pcpu_cpu_distance, pcpu_alloc_bootmem, pcpu_free_bootmem); if (rc) pr_warning("PERCPU: %s allocator failed (%d), " "falling back to page size\n", pcpu_fc_names[pcpu_chosen_fc], rc); } if (rc < 0) rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE, pcpu_alloc_bootmem, pcpu_free_bootmem, pcpu_populate_pte); if (rc < 0) panic("cannot initialize percpu area (err=%d)", rc); delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start; for_each_possible_cpu(cpu) __per_cpu_offset(cpu) = delta + pcpu_unit_offsets[cpu]; /* Setup %g5 for the boot cpu. */ __local_per_cpu_offset = __per_cpu_offset(smp_processor_id()); of_fill_in_cpu_data(); if (tlb_type == hypervisor) mdesc_fill_in_cpu_data(cpu_all_mask); }