diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/cgroup_freezer.c | 51 | ||||
-rw-r--r-- | kernel/freezer.c | 20 | ||||
-rw-r--r-- | kernel/power/Kconfig | 2 | ||||
-rw-r--r-- | kernel/profile.c | 2 | ||||
-rw-r--r-- | kernel/resource.c | 6 | ||||
-rw-r--r-- | kernel/sched_debug.c | 2 | ||||
-rw-r--r-- | kernel/signal.c | 3 | ||||
-rw-r--r-- | kernel/trace/Kconfig | 4 | ||||
-rw-r--r-- | kernel/trace/ftrace.c | 8 | ||||
-rw-r--r-- | kernel/trace/ring_buffer.c | 56 | ||||
-rw-r--r-- | kernel/trace/trace.c | 48 | ||||
-rw-r--r-- | kernel/trace/trace.h | 20 |
12 files changed, 144 insertions, 78 deletions
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c index e9505695449..7fa476f01d0 100644 --- a/kernel/cgroup_freezer.c +++ b/kernel/cgroup_freezer.c @@ -162,9 +162,13 @@ static int freezer_can_attach(struct cgroup_subsys *ss, struct task_struct *task) { struct freezer *freezer; - int retval; - /* Anything frozen can't move or be moved to/from */ + /* + * Anything frozen can't move or be moved to/from. + * + * Since orig_freezer->state == FROZEN means that @task has been + * frozen, so it's sufficient to check the latter condition. + */ if (is_task_frozen_enough(task)) return -EBUSY; @@ -173,13 +177,7 @@ static int freezer_can_attach(struct cgroup_subsys *ss, if (freezer->state == CGROUP_FROZEN) return -EBUSY; - retval = 0; - task_lock(task); - freezer = task_freezer(task); - if (freezer->state == CGROUP_FROZEN) - retval = -EBUSY; - task_unlock(task); - return retval; + return 0; } static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task) @@ -190,8 +188,9 @@ static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task) freezer = task_freezer(task); task_unlock(task); - BUG_ON(freezer->state == CGROUP_FROZEN); spin_lock_irq(&freezer->lock); + BUG_ON(freezer->state == CGROUP_FROZEN); + /* Locking avoids race with FREEZING -> THAWED transitions. */ if (freezer->state == CGROUP_FREEZING) freeze_task(task, true); @@ -276,25 +275,18 @@ static int try_to_freeze_cgroup(struct cgroup *cgroup, struct freezer *freezer) return num_cant_freeze_now ? -EBUSY : 0; } -static int unfreeze_cgroup(struct cgroup *cgroup, struct freezer *freezer) +static void unfreeze_cgroup(struct cgroup *cgroup, struct freezer *freezer) { struct cgroup_iter it; struct task_struct *task; cgroup_iter_start(cgroup, &it); while ((task = cgroup_iter_next(cgroup, &it))) { - int do_wake; - - task_lock(task); - do_wake = __thaw_process(task); - task_unlock(task); - if (do_wake) - wake_up_process(task); + thaw_process(task); } cgroup_iter_end(cgroup, &it); - freezer->state = CGROUP_THAWED; - return 0; + freezer->state = CGROUP_THAWED; } static int freezer_change_state(struct cgroup *cgroup, @@ -304,27 +296,22 @@ static int freezer_change_state(struct cgroup *cgroup, int retval = 0; freezer = cgroup_freezer(cgroup); + spin_lock_irq(&freezer->lock); + update_freezer_state(cgroup, freezer); if (goal_state == freezer->state) goto out; - switch (freezer->state) { + + switch (goal_state) { case CGROUP_THAWED: - retval = try_to_freeze_cgroup(cgroup, freezer); + unfreeze_cgroup(cgroup, freezer); break; - case CGROUP_FREEZING: - if (goal_state == CGROUP_FROZEN) { - /* Userspace is retrying after - * "/bin/echo FROZEN > freezer.state" returned -EBUSY */ - retval = try_to_freeze_cgroup(cgroup, freezer); - break; - } - /* state == FREEZING and goal_state == THAWED, so unfreeze */ case CGROUP_FROZEN: - retval = unfreeze_cgroup(cgroup, freezer); + retval = try_to_freeze_cgroup(cgroup, freezer); break; default: - break; + BUG(); } out: spin_unlock_irq(&freezer->lock); diff --git a/kernel/freezer.c b/kernel/freezer.c index ba6248b323e..2f4936cf708 100644 --- a/kernel/freezer.c +++ b/kernel/freezer.c @@ -121,16 +121,7 @@ void cancel_freezing(struct task_struct *p) } } -/* - * Wake up a frozen process - * - * task_lock() is needed to prevent the race with refrigerator() which may - * occur if the freezing of tasks fails. Namely, without the lock, if the - * freezing of tasks failed, thaw_tasks() might have run before a task in - * refrigerator() could call frozen_process(), in which case the task would be - * frozen and no one would thaw it. - */ -int __thaw_process(struct task_struct *p) +static int __thaw_process(struct task_struct *p) { if (frozen(p)) { p->flags &= ~PF_FROZEN; @@ -140,6 +131,15 @@ int __thaw_process(struct task_struct *p) return 0; } +/* + * Wake up a frozen process + * + * task_lock() is needed to prevent the race with refrigerator() which may + * occur if the freezing of tasks fails. Namely, without the lock, if the + * freezing of tasks failed, thaw_tasks() might have run before a task in + * refrigerator() could call frozen_process(), in which case the task would be + * frozen and no one would thaw it. + */ int thaw_process(struct task_struct *p) { task_lock(p); diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index dcd165f92a8..23bd4daeb96 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -96,7 +96,7 @@ config SUSPEND config PM_TEST_SUSPEND bool "Test suspend/resume and wakealarm during bootup" - depends on SUSPEND && PM_DEBUG && RTC_LIB=y + depends on SUSPEND && PM_DEBUG && RTC_CLASS=y ---help--- This option will let you suspend your machine during bootup, and make it wake up a few seconds later using an RTC wakeup alarm. diff --git a/kernel/profile.c b/kernel/profile.c index a9e422df6bf..9830a037d8d 100644 --- a/kernel/profile.c +++ b/kernel/profile.c @@ -102,7 +102,7 @@ int profile_setup(char *str) __setup("profile=", profile_setup); -int profile_init(void) +int __ref profile_init(void) { int buffer_bytes; if (!prof_on) diff --git a/kernel/resource.c b/kernel/resource.c index 7fec0e42723..4337063663e 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -17,6 +17,7 @@ #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/device.h> +#include <linux/pfn.h> #include <asm/io.h> @@ -522,7 +523,7 @@ static void __init __reserve_region_with_split(struct resource *root, { struct resource *parent = root; struct resource *conflict; - struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL); + struct resource *res = kzalloc(sizeof(*res), GFP_ATOMIC); if (!res) return; @@ -849,7 +850,8 @@ int iomem_map_sanity_check(resource_size_t addr, unsigned long size) continue; if (p->end < addr) continue; - if (p->start <= addr && (p->end >= addr + size - 1)) + if (PFN_DOWN(p->start) <= PFN_DOWN(addr) && + PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1)) continue; printk(KERN_WARNING "resource map sanity check conflict: " "0x%llx 0x%llx 0x%llx 0x%llx %s\n", diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c index ad958c1ec70..5ae17762ec3 100644 --- a/kernel/sched_debug.c +++ b/kernel/sched_debug.c @@ -319,7 +319,7 @@ static int __init init_sched_debug_procfs(void) { struct proc_dir_entry *pe; - pe = proc_create("sched_debug", 0644, NULL, &sched_debug_fops); + pe = proc_create("sched_debug", 0444, NULL, &sched_debug_fops); if (!pe) return -ENOMEM; return 0; diff --git a/kernel/signal.c b/kernel/signal.c index 105217da5c8..4530fc65445 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1144,7 +1144,8 @@ static int kill_something_info(int sig, struct siginfo *info, pid_t pid) struct task_struct * p; for_each_process(p) { - if (p->pid > 1 && !same_thread_group(p, current)) { + if (task_pid_vnr(p) > 1 && + !same_thread_group(p, current)) { int err = group_send_sig_info(sig, info, p); ++count; if (err != -EPERM) diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index e0cea282e0c..33dbefd471e 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -8,7 +8,6 @@ config NOP_TRACER config HAVE_FUNCTION_TRACER bool - select NOP_TRACER config HAVE_DYNAMIC_FTRACE bool @@ -26,8 +25,9 @@ config TRACING bool select DEBUG_FS select RING_BUFFER - select STACKTRACE + select STACKTRACE if STACKTRACE_SUPPORT select TRACEPOINTS + select NOP_TRACER menu "Tracers" diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 7618c528756..4a39d24568c 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1339,6 +1339,14 @@ void __init ftrace_init(void) } #else + +static int __init ftrace_nodyn_init(void) +{ + ftrace_enabled = 1; + return 0; +} +device_initcall(ftrace_nodyn_init); + # define ftrace_startup() do { } while (0) # define ftrace_shutdown() do { } while (0) # define ftrace_startup_sysctl() do { } while (0) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index cedf4e26828..3f338063864 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -1022,8 +1022,23 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer, struct ring_buffer_event *event; u64 ts, delta; int commit = 0; + int nr_loops = 0; again: + /* + * We allow for interrupts to reenter here and do a trace. + * If one does, it will cause this original code to loop + * back here. Even with heavy interrupts happening, this + * should only happen a few times in a row. If this happens + * 1000 times in a row, there must be either an interrupt + * storm or we have something buggy. + * Bail! + */ + if (unlikely(++nr_loops > 1000)) { + RB_WARN_ON(cpu_buffer, 1); + return NULL; + } + ts = ring_buffer_time_stamp(cpu_buffer->cpu); /* @@ -1532,10 +1547,23 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer) { struct buffer_page *reader = NULL; unsigned long flags; + int nr_loops = 0; spin_lock_irqsave(&cpu_buffer->lock, flags); again: + /* + * This should normally only loop twice. But because the + * start of the reader inserts an empty page, it causes + * a case where we will loop three times. There should be no + * reason to loop four times (that I know of). + */ + if (unlikely(++nr_loops > 3)) { + RB_WARN_ON(cpu_buffer, 1); + reader = NULL; + goto out; + } + reader = cpu_buffer->reader_page; /* If there's more to read, return this page */ @@ -1665,6 +1693,7 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts) struct ring_buffer_per_cpu *cpu_buffer; struct ring_buffer_event *event; struct buffer_page *reader; + int nr_loops = 0; if (!cpu_isset(cpu, buffer->cpumask)) return NULL; @@ -1672,6 +1701,19 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts) cpu_buffer = buffer->buffers[cpu]; again: + /* + * We repeat when a timestamp is encountered. It is possible + * to get multiple timestamps from an interrupt entering just + * as one timestamp is about to be written. The max times + * that this can happen is the number of nested interrupts we + * can have. Nesting 10 deep of interrupts is clearly + * an anomaly. + */ + if (unlikely(++nr_loops > 10)) { + RB_WARN_ON(cpu_buffer, 1); + return NULL; + } + reader = rb_get_reader_page(cpu_buffer); if (!reader) return NULL; @@ -1722,6 +1764,7 @@ ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts) struct ring_buffer *buffer; struct ring_buffer_per_cpu *cpu_buffer; struct ring_buffer_event *event; + int nr_loops = 0; if (ring_buffer_iter_empty(iter)) return NULL; @@ -1730,6 +1773,19 @@ ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts) buffer = cpu_buffer->buffer; again: + /* + * We repeat when a timestamp is encountered. It is possible + * to get multiple timestamps from an interrupt entering just + * as one timestamp is about to be written. The max times + * that this can happen is the number of nested interrupts we + * can have. Nesting 10 deep of interrupts is clearly + * an anomaly. + */ + if (unlikely(++nr_loops > 10)) { + RB_WARN_ON(cpu_buffer, 1); + return NULL; + } + if (rb_per_cpu_empty(cpu_buffer)) return NULL; diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index a610ca77155..9f3b478f917 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -656,7 +656,11 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, entry->preempt_count = pc & 0xff; entry->pid = (tsk) ? tsk->pid : 0; entry->flags = +#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | +#else + TRACE_FLAG_IRQS_NOSUPPORT | +#endif ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); @@ -701,6 +705,7 @@ static void ftrace_trace_stack(struct trace_array *tr, unsigned long flags, int skip, int pc) { +#ifdef CONFIG_STACKTRACE struct ring_buffer_event *event; struct stack_entry *entry; struct stack_trace trace; @@ -726,6 +731,7 @@ static void ftrace_trace_stack(struct trace_array *tr, save_stack_trace(&trace); ring_buffer_unlock_commit(tr->buffer, event, irq_flags); +#endif } void __trace_stack(struct trace_array *tr, @@ -1082,17 +1088,20 @@ static void s_stop(struct seq_file *m, void *p) mutex_unlock(&trace_types_lock); } -#define KRETPROBE_MSG "[unknown/kretprobe'd]" - #ifdef CONFIG_KRETPROBES -static inline int kretprobed(unsigned long addr) +static inline const char *kretprobed(const char *name) { - return addr == (unsigned long)kretprobe_trampoline; + static const char tramp_name[] = "kretprobe_trampoline"; + int size = sizeof(tramp_name); + + if (strncmp(tramp_name, name, size) == 0) + return "[unknown/kretprobe'd]"; + return name; } #else -static inline int kretprobed(unsigned long addr) +static inline const char *kretprobed(const char *name) { - return 0; + return name; } #endif /* CONFIG_KRETPROBES */ @@ -1101,10 +1110,13 @@ seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address) { #ifdef CONFIG_KALLSYMS char str[KSYM_SYMBOL_LEN]; + const char *name; kallsyms_lookup(address, NULL, NULL, NULL, str); - return trace_seq_printf(s, fmt, str); + name = kretprobed(str); + + return trace_seq_printf(s, fmt, name); #endif return 1; } @@ -1115,9 +1127,12 @@ seq_print_sym_offset(struct trace_seq *s, const char *fmt, { #ifdef CONFIG_KALLSYMS char str[KSYM_SYMBOL_LEN]; + const char *name; sprint_symbol(str, address); - return trace_seq_printf(s, fmt, str); + name = kretprobed(str); + + return trace_seq_printf(s, fmt, name); #endif return 1; } @@ -1244,7 +1259,8 @@ lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) trace_seq_printf(s, "%8.8s-%-5d ", comm, entry->pid); trace_seq_printf(s, "%3d", cpu); trace_seq_printf(s, "%c%c", - (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.', + (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : + (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' : '.', ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.')); hardirq = entry->flags & TRACE_FLAG_HARDIRQ; @@ -1370,10 +1386,7 @@ print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu) seq_print_ip_sym(s, field->ip, sym_flags); trace_seq_puts(s, " ("); - if (kretprobed(field->parent_ip)) - trace_seq_puts(s, KRETPROBE_MSG); - else - seq_print_ip_sym(s, field->parent_ip, sym_flags); + seq_print_ip_sym(s, field->parent_ip, sym_flags); trace_seq_puts(s, ")\n"); break; } @@ -1489,12 +1502,9 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter) ret = trace_seq_printf(s, " <-"); if (!ret) return TRACE_TYPE_PARTIAL_LINE; - if (kretprobed(field->parent_ip)) - ret = trace_seq_puts(s, KRETPROBE_MSG); - else - ret = seq_print_ip_sym(s, - field->parent_ip, - sym_flags); + ret = seq_print_ip_sym(s, + field->parent_ip, + sym_flags); if (!ret) return TRACE_TYPE_PARTIAL_LINE; } diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 6889ca48f1f..8465ad05270 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -120,18 +120,20 @@ struct trace_boot { /* * trace_flag_type is an enumeration that holds different * states when a trace occurs. These are: - * IRQS_OFF - interrupts were disabled - * NEED_RESCED - reschedule is requested - * HARDIRQ - inside an interrupt handler - * SOFTIRQ - inside a softirq handler - * CONT - multiple entries hold the trace item + * IRQS_OFF - interrupts were disabled + * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags + * NEED_RESCED - reschedule is requested + * HARDIRQ - inside an interrupt handler + * SOFTIRQ - inside a softirq handler + * CONT - multiple entries hold the trace item */ enum trace_flag_type { TRACE_FLAG_IRQS_OFF = 0x01, - TRACE_FLAG_NEED_RESCHED = 0x02, - TRACE_FLAG_HARDIRQ = 0x04, - TRACE_FLAG_SOFTIRQ = 0x08, - TRACE_FLAG_CONT = 0x10, + TRACE_FLAG_IRQS_NOSUPPORT = 0x02, + TRACE_FLAG_NEED_RESCHED = 0x04, + TRACE_FLAG_HARDIRQ = 0x08, + TRACE_FLAG_SOFTIRQ = 0x10, + TRACE_FLAG_CONT = 0x20, }; #define TRACE_BUF_SIZE 1024 |