diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cpu.c | 39 | ||||
| -rw-r--r-- | kernel/sched/core.c | 21 | ||||
| -rw-r--r-- | kernel/trace/ipc_logging.c | 6 |
3 files changed, 55 insertions, 11 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index 8b6940755e4a..0ca3599cee1f 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -530,9 +530,41 @@ out: return ret; } +static int switch_to_rt_policy(void) +{ + struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; + unsigned int policy = current->policy; + int err; + + /* Nobody should be attempting hotplug from these policy contexts. */ + if (policy == SCHED_BATCH || policy == SCHED_IDLE || + policy == SCHED_DEADLINE) + return -EPERM; + + if (policy == SCHED_FIFO || policy == SCHED_RR) + return 1; + + /* Only SCHED_NORMAL left. */ + err = sched_setscheduler_nocheck(current, SCHED_FIFO, ¶m); + return err; + +} + +static int switch_to_fair_policy(void) +{ + struct sched_param param = { .sched_priority = 0 }; + + return sched_setscheduler_nocheck(current, SCHED_NORMAL, ¶m); +} + int cpu_up(unsigned int cpu) { int err = 0; + int switch_err = 0; + + switch_err = switch_to_rt_policy(); + if (switch_err < 0) + return switch_err; if (!cpu_possible(cpu)) { pr_err("can't online cpu %d because it is not configured as may-hotadd at boot time\n", @@ -558,6 +590,13 @@ int cpu_up(unsigned int cpu) out: cpu_maps_update_done(); + + if (!switch_err) { + switch_err = switch_to_fair_policy(); + pr_err("Hotplug policy switch err. Task %s pid=%d\n", + current->comm, current->pid); + } + return err; } EXPORT_SYMBOL_GPL(cpu_up); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 1017a3f77391..e107c4d6b385 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3364,6 +3364,9 @@ NOKPROBE_SYMBOL(preempt_count_sub); */ static noinline void __schedule_bug(struct task_struct *prev) { + /* Save this before calling printk(), since that will clobber it */ + unsigned long preempt_disable_ip = get_preempt_disable_ip(current); + if (oops_in_progress) return; @@ -3374,13 +3377,12 @@ static noinline void __schedule_bug(struct task_struct *prev) print_modules(); if (irqs_disabled()) print_irqtrace_events(prev); -#ifdef CONFIG_DEBUG_PREEMPT - if (in_atomic_preempt_off()) { + if (IS_ENABLED(CONFIG_DEBUG_PREEMPT) + && in_atomic_preempt_off()) { pr_err("Preemption disabled at:"); - print_ip_sym(current->preempt_disable_ip); + print_ip_sym(preempt_disable_ip); pr_cont("\n"); } -#endif #ifdef CONFIG_PANIC_ON_SCHED_BUG BUG(); #endif @@ -8513,6 +8515,7 @@ EXPORT_SYMBOL(__might_sleep); void ___might_sleep(const char *file, int line, int preempt_offset) { static unsigned long prev_jiffy; /* ratelimiting */ + unsigned long preempt_disable_ip; rcu_sleep_check(); /* WARN_ON_ONCE() by default, no rate limit reqd. */ if ((preempt_count_equals(preempt_offset) && !irqs_disabled() && @@ -8525,6 +8528,9 @@ void ___might_sleep(const char *file, int line, int preempt_offset) return; prev_jiffy = jiffies; + /* Save this before calling printk(), since that will clobber it */ + preempt_disable_ip = get_preempt_disable_ip(current); + printk(KERN_ERR "BUG: sleeping function called from invalid context at %s:%d\n", file, line); @@ -8539,13 +8545,12 @@ void ___might_sleep(const char *file, int line, int preempt_offset) debug_show_held_locks(current); if (irqs_disabled()) print_irqtrace_events(current); -#ifdef CONFIG_DEBUG_PREEMPT - if (!preempt_count_equals(preempt_offset)) { + if (IS_ENABLED(CONFIG_DEBUG_PREEMPT) + && !preempt_count_equals(preempt_offset)) { pr_err("Preemption disabled at:"); - print_ip_sym(current->preempt_disable_ip); + print_ip_sym(preempt_disable_ip); pr_cont("\n"); } -#endif #ifdef CONFIG_PANIC_ON_SCHED_BUG BUG(); #endif diff --git a/kernel/trace/ipc_logging.c b/kernel/trace/ipc_logging.c index 2c3e0998d400..ed29c38cd7fb 100644 --- a/kernel/trace/ipc_logging.c +++ b/kernel/trace/ipc_logging.c @@ -1,4 +1,4 @@ -/* Copyright (c) 2012-2016, The Linux Foundation. All rights reserved. +/* Copyright (c) 2012-2017, The Linux Foundation. All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 and @@ -507,8 +507,8 @@ int ipc_log_string(void *ilctxt, const char *fmt, ...) tsv_qtimer_write(&ectxt); avail_size = (MAX_MSG_SIZE - (ectxt.offset + hdr_size)); va_start(arg_list, fmt); - data_size = vsnprintf((ectxt.buff + ectxt.offset + hdr_size), - avail_size, fmt, arg_list); + data_size = vscnprintf((ectxt.buff + ectxt.offset + hdr_size), + avail_size, fmt, arg_list); va_end(arg_list); tsv_write_header(&ectxt, TSV_TYPE_BYTE_ARRAY, data_size); ectxt.offset += data_size; |