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-rw-r--r--kernel/trace/trace.c901
1 files changed, 759 insertions, 142 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index d86e3252f30..8ebe0070c47 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -30,6 +30,7 @@
#include <linux/gfp.h>
#include <linux/fs.h>
#include <linux/kprobes.h>
+#include <linux/seq_file.h>
#include <linux/writeback.h>
#include <linux/stacktrace.h>
@@ -43,6 +44,38 @@
unsigned long __read_mostly tracing_max_latency = (cycle_t)ULONG_MAX;
unsigned long __read_mostly tracing_thresh;
+/*
+ * We need to change this state when a selftest is running.
+ * A selftest will lurk into the ring-buffer to count the
+ * entries inserted during the selftest although some concurrent
+ * insertions into the ring-buffer such as ftrace_printk could occurred
+ * at the same time, giving false positive or negative results.
+ */
+static bool __read_mostly tracing_selftest_running;
+
+/* For tracers that don't implement custom flags */
+static struct tracer_opt dummy_tracer_opt[] = {
+ { }
+};
+
+static struct tracer_flags dummy_tracer_flags = {
+ .val = 0,
+ .opts = dummy_tracer_opt
+};
+
+static int dummy_set_flag(u32 old_flags, u32 bit, int set)
+{
+ return 0;
+}
+
+/*
+ * Kill all tracing for good (never come back).
+ * It is initialized to 1 but will turn to zero if the initialization
+ * of the tracer is successful. But that is the only place that sets
+ * this back to zero.
+ */
+int tracing_disabled = 1;
+
static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled);
static inline void ftrace_disable_cpu(void)
@@ -62,7 +95,36 @@ static cpumask_t __read_mostly tracing_buffer_mask;
#define for_each_tracing_cpu(cpu) \
for_each_cpu_mask(cpu, tracing_buffer_mask)
-static int tracing_disabled = 1;
+/*
+ * ftrace_dump_on_oops - variable to dump ftrace buffer on oops
+ *
+ * If there is an oops (or kernel panic) and the ftrace_dump_on_oops
+ * is set, then ftrace_dump is called. This will output the contents
+ * of the ftrace buffers to the console. This is very useful for
+ * capturing traces that lead to crashes and outputing it to a
+ * serial console.
+ *
+ * It is default off, but you can enable it with either specifying
+ * "ftrace_dump_on_oops" in the kernel command line, or setting
+ * /proc/sys/kernel/ftrace_dump_on_oops to true.
+ */
+int ftrace_dump_on_oops;
+
+static int tracing_set_tracer(char *buf);
+
+static int __init set_ftrace(char *str)
+{
+ tracing_set_tracer(str);
+ return 1;
+}
+__setup("ftrace", set_ftrace);
+
+static int __init set_ftrace_dump_on_oops(char *str)
+{
+ ftrace_dump_on_oops = 1;
+ return 1;
+}
+__setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops);
long
ns2usecs(cycle_t nsec)
@@ -112,6 +174,19 @@ static DEFINE_PER_CPU(struct trace_array_cpu, max_data);
/* tracer_enabled is used to toggle activation of a tracer */
static int tracer_enabled = 1;
+/**
+ * tracing_is_enabled - return tracer_enabled status
+ *
+ * This function is used by other tracers to know the status
+ * of the tracer_enabled flag. Tracers may use this function
+ * to know if it should enable their features when starting
+ * up. See irqsoff tracer for an example (start_irqsoff_tracer).
+ */
+int tracing_is_enabled(void)
+{
+ return tracer_enabled;
+}
+
/* function tracing enabled */
int ftrace_function_enabled;
@@ -153,8 +228,9 @@ static DEFINE_MUTEX(trace_types_lock);
/* trace_wait is a waitqueue for tasks blocked on trace_poll */
static DECLARE_WAIT_QUEUE_HEAD(trace_wait);
-/* trace_flags holds iter_ctrl options */
-unsigned long trace_flags = TRACE_ITER_PRINT_PARENT;
+/* trace_flags holds trace_options default values */
+unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
+ TRACE_ITER_ANNOTATE;
/**
* trace_wake_up - wake up tasks waiting for trace input
@@ -193,13 +269,6 @@ unsigned long nsecs_to_usecs(unsigned long nsecs)
return nsecs / 1000;
}
-/*
- * TRACE_ITER_SYM_MASK masks the options in trace_flags that
- * control the output of kernel symbols.
- */
-#define TRACE_ITER_SYM_MASK \
- (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
-
/* These must match the bit postions in trace_iterator_flags */
static const char *trace_options[] = {
"print-parent",
@@ -213,6 +282,11 @@ static const char *trace_options[] = {
"stacktrace",
"sched-tree",
"ftrace_printk",
+ "ftrace_preempt",
+ "branch",
+ "annotate",
+ "userstacktrace",
+ "sym-userobj",
NULL
};
@@ -359,6 +433,28 @@ trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len)
return trace_seq_putmem(s, hex, j);
}
+static int
+trace_seq_path(struct trace_seq *s, struct path *path)
+{
+ unsigned char *p;
+
+ if (s->len >= (PAGE_SIZE - 1))
+ return 0;
+ p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
+ if (!IS_ERR(p)) {
+ p = mangle_path(s->buffer + s->len, p, "\n");
+ if (p) {
+ s->len = p - s->buffer;
+ return 1;
+ }
+ } else {
+ s->buffer[s->len++] = '?';
+ return 1;
+ }
+
+ return 0;
+}
+
static void
trace_seq_reset(struct trace_seq *s)
{
@@ -470,7 +566,17 @@ int register_tracer(struct tracer *type)
return -1;
}
+ /*
+ * When this gets called we hold the BKL which means that
+ * preemption is disabled. Various trace selftests however
+ * need to disable and enable preemption for successful tests.
+ * So we drop the BKL here and grab it after the tests again.
+ */
+ unlock_kernel();
mutex_lock(&trace_types_lock);
+
+ tracing_selftest_running = true;
+
for (t = trace_types; t; t = t->next) {
if (strcmp(type->name, t->name) == 0) {
/* already found */
@@ -481,12 +587,20 @@ int register_tracer(struct tracer *type)
}
}
+ if (!type->set_flag)
+ type->set_flag = &dummy_set_flag;
+ if (!type->flags)
+ type->flags = &dummy_tracer_flags;
+ else
+ if (!type->flags->opts)
+ type->flags->opts = dummy_tracer_opt;
+
#ifdef CONFIG_FTRACE_STARTUP_TEST
if (type->selftest) {
struct tracer *saved_tracer = current_trace;
struct trace_array *tr = &global_trace;
- int saved_ctrl = tr->ctrl;
int i;
+
/*
* Run a selftest on this tracer.
* Here we reset the trace buffer, and set the current
@@ -494,25 +608,23 @@ int register_tracer(struct tracer *type)
* internal tracing to verify that everything is in order.
* If we fail, we do not register this tracer.
*/
- for_each_tracing_cpu(i) {
+ for_each_tracing_cpu(i)
tracing_reset(tr, i);
- }
+
current_trace = type;
- tr->ctrl = 0;
/* the test is responsible for initializing and enabling */
pr_info("Testing tracer %s: ", type->name);
ret = type->selftest(type, tr);
/* the test is responsible for resetting too */
current_trace = saved_tracer;
- tr->ctrl = saved_ctrl;
if (ret) {
printk(KERN_CONT "FAILED!\n");
goto out;
}
/* Only reset on passing, to avoid touching corrupted buffers */
- for_each_tracing_cpu(i) {
+ for_each_tracing_cpu(i)
tracing_reset(tr, i);
- }
+
printk(KERN_CONT "PASSED\n");
}
#endif
@@ -524,7 +636,9 @@ int register_tracer(struct tracer *type)
max_tracer_type_len = len;
out:
+ tracing_selftest_running = false;
mutex_unlock(&trace_types_lock);
+ lock_kernel();
return ret;
}
@@ -581,6 +695,91 @@ static void trace_init_cmdlines(void)
cmdline_idx = 0;
}
+static int trace_stop_count;
+static DEFINE_SPINLOCK(tracing_start_lock);
+
+/**
+ * ftrace_off_permanent - disable all ftrace code permanently
+ *
+ * This should only be called when a serious anomally has
+ * been detected. This will turn off the function tracing,
+ * ring buffers, and other tracing utilites. It takes no
+ * locks and can be called from any context.
+ */
+void ftrace_off_permanent(void)
+{
+ tracing_disabled = 1;
+ ftrace_stop();
+ tracing_off_permanent();
+}
+
+/**
+ * tracing_start - quick start of the tracer
+ *
+ * If tracing is enabled but was stopped by tracing_stop,
+ * this will start the tracer back up.
+ */
+void tracing_start(void)
+{
+ struct ring_buffer *buffer;
+ unsigned long flags;
+
+ if (tracing_disabled)
+ return;
+
+ spin_lock_irqsave(&tracing_start_lock, flags);
+ if (--trace_stop_count)
+ goto out;
+
+ if (trace_stop_count < 0) {
+ /* Someone screwed up their debugging */
+ WARN_ON_ONCE(1);
+ trace_stop_count = 0;
+ goto out;
+ }
+
+
+ buffer = global_trace.buffer;
+ if (buffer)
+ ring_buffer_record_enable(buffer);
+
+ buffer = max_tr.buffer;
+ if (buffer)
+ ring_buffer_record_enable(buffer);
+
+ ftrace_start();
+ out:
+ spin_unlock_irqrestore(&tracing_start_lock, flags);
+}
+
+/**
+ * tracing_stop - quick stop of the tracer
+ *
+ * Light weight way to stop tracing. Use in conjunction with
+ * tracing_start.
+ */
+void tracing_stop(void)
+{
+ struct ring_buffer *buffer;
+ unsigned long flags;
+
+ ftrace_stop();
+ spin_lock_irqsave(&tracing_start_lock, flags);
+ if (trace_stop_count++)
+ goto out;
+
+ buffer = global_trace.buffer;
+ if (buffer)
+ ring_buffer_record_disable(buffer);
+
+ buffer = max_tr.buffer;
+ if (buffer)
+ ring_buffer_record_disable(buffer);
+
+ out:
+ spin_unlock_irqrestore(&tracing_start_lock, flags);
+}
+
void trace_stop_cmdline_recording(void);
static void trace_save_cmdline(struct task_struct *tsk)
@@ -618,7 +817,7 @@ static void trace_save_cmdline(struct task_struct *tsk)
spin_unlock(&trace_cmdline_lock);
}
-static char *trace_find_cmdline(int pid)
+char *trace_find_cmdline(int pid)
{
char *cmdline = "<...>";
unsigned map;
@@ -655,6 +854,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
entry->preempt_count = pc & 0xff;
entry->pid = (tsk) ? tsk->pid : 0;
+ entry->tgid = (tsk) ? tsk->tgid : 0;
entry->flags =
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
@@ -691,6 +891,56 @@ trace_function(struct trace_array *tr, struct trace_array_cpu *data,
ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
}
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+static void __trace_graph_entry(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ struct ftrace_graph_ent *trace,
+ unsigned long flags,
+ int pc)
+{
+ struct ring_buffer_event *event;
+ struct ftrace_graph_ent_entry *entry;
+ unsigned long irq_flags;
+
+ if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
+ return;
+
+ event = ring_buffer_lock_reserve(global_trace.buffer, sizeof(*entry),
+ &irq_flags);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ tracing_generic_entry_update(&entry->ent, flags, pc);
+ entry->ent.type = TRACE_GRAPH_ENT;
+ entry->graph_ent = *trace;
+ ring_buffer_unlock_commit(global_trace.buffer, event, irq_flags);
+}
+
+static void __trace_graph_return(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ struct ftrace_graph_ret *trace,
+ unsigned long flags,
+ int pc)
+{
+ struct ring_buffer_event *event;
+ struct ftrace_graph_ret_entry *entry;
+ unsigned long irq_flags;
+
+ if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
+ return;
+
+ event = ring_buffer_lock_reserve(global_trace.buffer, sizeof(*entry),
+ &irq_flags);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ tracing_generic_entry_update(&entry->ent, flags, pc);
+ entry->ent.type = TRACE_GRAPH_RET;
+ entry->ret = *trace;
+ ring_buffer_unlock_commit(global_trace.buffer, event, irq_flags);
+}
+#endif
+
void
ftrace(struct trace_array *tr, struct trace_array_cpu *data,
unsigned long ip, unsigned long parent_ip, unsigned long flags,
@@ -742,6 +992,46 @@ void __trace_stack(struct trace_array *tr,
ftrace_trace_stack(tr, data, flags, skip, preempt_count());
}
+static void ftrace_trace_userstack(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ unsigned long flags, int pc)
+{
+#ifdef CONFIG_STACKTRACE
+ struct ring_buffer_event *event;
+ struct userstack_entry *entry;
+ struct stack_trace trace;
+ unsigned long irq_flags;
+
+ if (!(trace_flags & TRACE_ITER_USERSTACKTRACE))
+ return;
+
+ event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
+ &irq_flags);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ tracing_generic_entry_update(&entry->ent, flags, pc);
+ entry->ent.type = TRACE_USER_STACK;
+
+ memset(&entry->caller, 0, sizeof(entry->caller));
+
+ trace.nr_entries = 0;
+ trace.max_entries = FTRACE_STACK_ENTRIES;
+ trace.skip = 0;
+ trace.entries = entry->caller;
+
+ save_stack_trace_user(&trace);
+ ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
+#endif
+}
+
+void __trace_userstack(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ unsigned long flags)
+{
+ ftrace_trace_userstack(tr, data, flags, preempt_count());
+}
+
static void
ftrace_trace_special(void *__tr, void *__data,
unsigned long arg1, unsigned long arg2, unsigned long arg3,
@@ -765,6 +1055,7 @@ ftrace_trace_special(void *__tr, void *__data,
entry->arg3 = arg3;
ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
ftrace_trace_stack(tr, data, irq_flags, 4, pc);
+ ftrace_trace_userstack(tr, data, irq_flags, pc);
trace_wake_up();
}
@@ -803,6 +1094,7 @@ tracing_sched_switch_trace(struct trace_array *tr,
entry->next_cpu = task_cpu(next);
ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
ftrace_trace_stack(tr, data, flags, 5, pc);
+ ftrace_trace_userstack(tr, data, flags, pc);
}
void
@@ -832,6 +1124,7 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
entry->next_cpu = task_cpu(wakee);
ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
ftrace_trace_stack(tr, data, flags, 6, pc);
+ ftrace_trace_userstack(tr, data, flags, pc);
trace_wake_up();
}
@@ -841,26 +1134,28 @@ ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3)
{
struct trace_array *tr = &global_trace;
struct trace_array_cpu *data;
+ unsigned long flags;
int cpu;
int pc;
- if (tracing_disabled || !tr->ctrl)
+ if (tracing_disabled)
return;
pc = preempt_count();
- preempt_disable_notrace();
+ local_irq_save(flags);
cpu = raw_smp_processor_id();
data = tr->data[cpu];
- if (likely(!atomic_read(&data->disabled)))
+ if (likely(atomic_inc_return(&data->disabled) == 1))
ftrace_trace_special(tr, data, arg1, arg2, arg3, pc);
- preempt_enable_notrace();
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
}
#ifdef CONFIG_FUNCTION_TRACER
static void
-function_trace_call(unsigned long ip, unsigned long parent_ip)
+function_trace_call_preempt_only(unsigned long ip, unsigned long parent_ip)
{
struct trace_array *tr = &global_trace;
struct trace_array_cpu *data;
@@ -873,8 +1168,7 @@ function_trace_call(unsigned long ip, unsigned long parent_ip)
return;
pc = preempt_count();
- resched = need_resched();
- preempt_disable_notrace();
+ resched = ftrace_preempt_disable();
local_save_flags(flags);
cpu = raw_smp_processor_id();
data = tr->data[cpu];
@@ -884,11 +1178,96 @@ function_trace_call(unsigned long ip, unsigned long parent_ip)
trace_function(tr, data, ip, parent_ip, flags, pc);
atomic_dec(&data->disabled);
- if (resched)
- preempt_enable_no_resched_notrace();
- else
- preempt_enable_notrace();
+ ftrace_preempt_enable(resched);
+}
+
+static void
+function_trace_call(unsigned long ip, unsigned long parent_ip)
+{
+ struct trace_array *tr = &global_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+ int pc;
+
+ if (unlikely(!ftrace_function_enabled))
+ return;
+
+ /*
+ * Need to use raw, since this must be called before the
+ * recursive protection is performed.
+ */
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+
+ if (likely(disabled == 1)) {
+ pc = preempt_count();
+ trace_function(tr, data, ip, parent_ip, flags, pc);
+ }
+
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
+}
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+int trace_graph_entry(struct ftrace_graph_ent *trace)
+{
+ struct trace_array *tr = &global_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+ int pc;
+
+ if (!ftrace_trace_task(current))
+ return 0;
+
+ if (!ftrace_graph_addr(trace->func))
+ return 0;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+ if (likely(disabled == 1)) {
+ pc = preempt_count();
+ __trace_graph_entry(tr, data, trace, flags, pc);
+ }
+ /* Only do the atomic if it is not already set */
+ if (!test_tsk_trace_graph(current))
+ set_tsk_trace_graph(current);
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
+
+ return 1;
+}
+
+void trace_graph_return(struct ftrace_graph_ret *trace)
+{
+ struct trace_array *tr = &global_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+ int pc;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+ if (likely(disabled == 1)) {
+ pc = preempt_count();
+ __trace_graph_return(tr, data, trace, flags, pc);
+ }
+ if (!trace->depth)
+ clear_tsk_trace_graph(current);
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
}
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
static struct ftrace_ops trace_ops __read_mostly =
{
@@ -898,9 +1277,14 @@ static struct ftrace_ops trace_ops __read_mostly =
void tracing_start_function_trace(void)
{
ftrace_function_enabled = 0;
+
+ if (trace_flags & TRACE_ITER_PREEMPTONLY)
+ trace_ops.func = function_trace_call_preempt_only;
+ else
+ trace_ops.func = function_trace_call;
+
register_ftrace_function(&trace_ops);
- if (tracer_enabled)
- ftrace_function_enabled = 1;
+ ftrace_function_enabled = 1;
}
void tracing_stop_function_trace(void)
@@ -912,6 +1296,7 @@ void tracing_stop_function_trace(void)
enum trace_file_type {
TRACE_FILE_LAT_FMT = 1,
+ TRACE_FILE_ANNOTATE = 2,
};
static void trace_iterator_increment(struct trace_iterator *iter, int cpu)
@@ -1047,10 +1432,6 @@ static void *s_start(struct seq_file *m, loff_t *pos)
atomic_inc(&trace_record_cmdline_disabled);
- /* let the tracer grab locks here if needed */
- if (current_trace->start)
- current_trace->start(iter);
-
if (*pos != iter->pos) {
iter->ent = NULL;
iter->cpu = 0;
@@ -1077,14 +1458,7 @@ static void *s_start(struct seq_file *m, loff_t *pos)
static void s_stop(struct seq_file *m, void *p)
{
- struct trace_iterator *iter = m->private;
-
atomic_dec(&trace_record_cmdline_disabled);
-
- /* let the tracer release locks here if needed */
- if (current_trace && current_trace == iter->trace && iter->trace->stop)
- iter->trace->stop(iter);
-
mutex_unlock(&trace_types_lock);
}
@@ -1143,7 +1517,7 @@ seq_print_sym_offset(struct trace_seq *s, const char *fmt,
# define IP_FMT "%016lx"
#endif
-static int
+int
seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
{
int ret;
@@ -1164,6 +1538,78 @@ seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
return ret;
}
+static inline int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
+ unsigned long ip, unsigned long sym_flags)
+{
+ struct file *file = NULL;
+ unsigned long vmstart = 0;
+ int ret = 1;
+
+ if (mm) {
+ const struct vm_area_struct *vma;
+
+ down_read(&mm->mmap_sem);
+ vma = find_vma(mm, ip);
+ if (vma) {
+ file = vma->vm_file;
+ vmstart = vma->vm_start;
+ }
+ if (file) {
+ ret = trace_seq_path(s, &file->f_path);
+ if (ret)
+ ret = trace_seq_printf(s, "[+0x%lx]", ip - vmstart);
+ }
+ up_read(&mm->mmap_sem);
+ }
+ if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
+ ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
+ return ret;
+}
+
+static int
+seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
+ unsigned long sym_flags)
+{
+ struct mm_struct *mm = NULL;
+ int ret = 1;
+ unsigned int i;
+
+ if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
+ struct task_struct *task;
+ /*
+ * we do the lookup on the thread group leader,
+ * since individual threads might have already quit!
+ */
+ rcu_read_lock();
+ task = find_task_by_vpid(entry->ent.tgid);
+ if (task)
+ mm = get_task_mm(task);
+ rcu_read_unlock();
+ }
+
+ for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
+ unsigned long ip = entry->caller[i];
+
+ if (ip == ULONG_MAX || !ret)
+ break;
+ if (i && ret)
+ ret = trace_seq_puts(s, " <- ");
+ if (!ip) {
+ if (ret)
+ ret = trace_seq_puts(s, "??");
+ continue;
+ }
+ if (!ret)
+ break;
+ if (ret)
+ ret = seq_print_user_ip(s, mm, ip, sym_flags);
+ }
+
+ if (mm)
+ mmput(mm);
+ return ret;
+}
+
static void print_lat_help_header(struct seq_file *m)
{
seq_puts(m, "# _------=> CPU# \n");
@@ -1338,6 +1784,23 @@ void trace_seq_print_cont(struct trace_seq *s, struct trace_iterator *iter)
trace_seq_putc(s, '\n');
}
+static void test_cpu_buff_start(struct trace_iterator *iter)
+{
+ struct trace_seq *s = &iter->seq;
+
+ if (!(trace_flags & TRACE_ITER_ANNOTATE))
+ return;
+
+ if (!(iter->iter_flags & TRACE_FILE_ANNOTATE))
+ return;
+
+ if (cpu_isset(iter->cpu, iter->started))
+ return;
+
+ cpu_set(iter->cpu, iter->started);
+ trace_seq_printf(s, "##### CPU %u buffer started ####\n", iter->cpu);
+}
+
static enum print_line_t
print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu)
{
@@ -1357,6 +1820,8 @@ print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu)
if (entry->type == TRACE_CONT)
return TRACE_TYPE_HANDLED;
+ test_cpu_buff_start(iter);
+
next_entry = find_next_entry(iter, NULL, &next_ts);
if (!next_entry)
next_ts = iter->ts;
@@ -1448,6 +1913,27 @@ print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu)
trace_seq_print_cont(s, iter);
break;
}
+ case TRACE_BRANCH: {
+ struct trace_branch *field;
+
+ trace_assign_type(field, entry);
+
+ trace_seq_printf(s, "[%s] %s:%s:%d\n",
+ field->correct ? " ok " : " MISS ",
+ field->func,
+ field->file,
+ field->line);
+ break;
+ }
+ case TRACE_USER_STACK: {
+ struct userstack_entry *field;
+
+ trace_assign_type(field, entry);
+
+ seq_print_userip_objs(field, s, sym_flags);
+ trace_seq_putc(s, '\n');
+ break;
+ }
default:
trace_seq_printf(s, "Unknown type %d\n", entry->type);
}
@@ -1472,6 +1958,8 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
if (entry->type == TRACE_CONT)
return TRACE_TYPE_HANDLED;
+ test_cpu_buff_start(iter);
+
comm = trace_find_cmdline(iter->ent->pid);
t = ns2usecs(iter->ts);
@@ -1581,6 +2069,37 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
trace_seq_print_cont(s, iter);
break;
}
+ case TRACE_GRAPH_RET: {
+ return print_graph_function(iter);
+ }
+ case TRACE_GRAPH_ENT: {
+ return print_graph_function(iter);
+ }
+ case TRACE_BRANCH: {
+ struct trace_branch *field;
+
+ trace_assign_type(field, entry);
+
+ trace_seq_printf(s, "[%s] %s:%s:%d\n",
+ field->correct ? " ok " : " MISS ",
+ field->func,
+ field->file,
+ field->line);
+ break;
+ }
+ case TRACE_USER_STACK: {
+ struct userstack_entry *field;
+
+ trace_assign_type(field, entry);
+
+ ret = seq_print_userip_objs(field, s, sym_flags);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ ret = trace_seq_putc(s, '\n');
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ break;
+ }
}
return TRACE_TYPE_HANDLED;
}
@@ -1640,6 +2159,7 @@ static enum print_line_t print_raw_fmt(struct trace_iterator *iter)
break;
}
case TRACE_SPECIAL:
+ case TRACE_USER_STACK:
case TRACE_STACK: {
struct special_entry *field;
@@ -1728,6 +2248,7 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter)
break;
}
case TRACE_SPECIAL:
+ case TRACE_USER_STACK:
case TRACE_STACK: {
struct special_entry *field;
@@ -1782,6 +2303,7 @@ static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
break;
}
case TRACE_SPECIAL:
+ case TRACE_USER_STACK:
case TRACE_STACK: {
struct special_entry *field;
@@ -1847,7 +2369,9 @@ static int s_show(struct seq_file *m, void *v)
seq_printf(m, "# tracer: %s\n", iter->trace->name);
seq_puts(m, "#\n");
}
- if (iter->iter_flags & TRACE_FILE_LAT_FMT) {
+ if (iter->trace && iter->trace->print_header)
+ iter->trace->print_header(m);
+ else if (iter->iter_flags & TRACE_FILE_LAT_FMT) {
/* print nothing if the buffers are empty */
if (trace_empty(iter))
return 0;
@@ -1899,6 +2423,15 @@ __tracing_open(struct inode *inode, struct file *file, int *ret)
iter->trace = current_trace;
iter->pos = -1;
+ /* Notify the tracer early; before we stop tracing. */
+ if (iter->trace && iter->trace->open)
+ iter->trace->open(iter);
+
+ /* Annotate start of buffers if we had overruns */
+ if (ring_buffer_overruns(iter->tr->buffer))
+ iter->iter_flags |= TRACE_FILE_ANNOTATE;
+
+
for_each_tracing_cpu(cpu) {
iter->buffer_iter[cpu] =
@@ -1917,13 +2450,7 @@ __tracing_open(struct inode *inode, struct file *file, int *ret)
m->private = iter;
/* stop the trace while dumping */
- if (iter->tr->ctrl) {
- tracer_enabled = 0;
- ftrace_function_enabled = 0;
- }
-
- if (iter->trace && iter->trace->open)
- iter->trace->open(iter);
+ tracing_stop();
mutex_unlock(&trace_types_lock);
@@ -1966,14 +2493,7 @@ int tracing_release(struct inode *inode, struct file *file)
iter->trace->close(iter);
/* reenable tracing if it was previously enabled */
- if (iter->tr->ctrl) {
- tracer_enabled = 1;
- /*
- * It is safe to enable function tracing even if it
- * isn't used
- */
- ftrace_function_enabled = 1;
- }
+ tracing_start();
mutex_unlock(&trace_types_lock);
seq_release(inode, file);
@@ -2151,7 +2671,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
if (err)
goto err_unlock;
- raw_local_irq_disable();
+ local_irq_disable();
__raw_spin_lock(&ftrace_max_lock);
for_each_tracing_cpu(cpu) {
/*
@@ -2168,7 +2688,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
}
}
__raw_spin_unlock(&ftrace_max_lock);
- raw_local_irq_enable();
+ local_irq_enable();
tracing_cpumask = tracing_cpumask_new;
@@ -2189,13 +2709,16 @@ static struct file_operations tracing_cpumask_fops = {
};
static ssize_t
-tracing_iter_ctrl_read(struct file *filp, char __user *ubuf,
+tracing_trace_options_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
+ int i;
char *buf;
int r = 0;
int len = 0;
- int i;
+ u32 tracer_flags = current_trace->flags->val;
+ struct tracer_opt *trace_opts = current_trace->flags->opts;
+
/* calulate max size */
for (i = 0; trace_options[i]; i++) {
@@ -2203,6 +2726,15 @@ tracing_iter_ctrl_read(struct file *filp, char __user *ubuf,
len += 3; /* "no" and space */
}
+ /*
+ * Increase the size with names of options specific
+ * of the current tracer.
+ */
+ for (i = 0; trace_opts[i].name; i++) {
+ len += strlen(trace_opts[i].name);
+ len += 3; /* "no" and space */
+ }
+
/* +2 for \n and \0 */
buf = kmalloc(len + 2, GFP_KERNEL);
if (!buf)
@@ -2215,6 +2747,15 @@ tracing_iter_ctrl_read(struct file *filp, char __user *ubuf,
r += sprintf(buf + r, "no%s ", trace_options[i]);
}
+ for (i = 0; trace_opts[i].name; i++) {
+ if (tracer_flags & trace_opts[i].bit)
+ r += sprintf(buf + r, "%s ",
+ trace_opts[i].name);
+ else
+ r += sprintf(buf + r, "no%s ",
+ trace_opts[i].name);
+ }
+
r += sprintf(buf + r, "\n");
WARN_ON(r >= len + 2);
@@ -2225,13 +2766,48 @@ tracing_iter_ctrl_read(struct file *filp, char __user *ubuf,
return r;
}
+/* Try to assign a tracer specific option */
+static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
+{
+ struct tracer_flags *trace_flags = trace->flags;
+ struct tracer_opt *opts = NULL;
+ int ret = 0, i = 0;
+ int len;
+
+ for (i = 0; trace_flags->opts[i].name; i++) {
+ opts = &trace_flags->opts[i];
+ len = strlen(opts->name);
+
+ if (strncmp(cmp, opts->name, len) == 0) {
+ ret = trace->set_flag(trace_flags->val,
+ opts->bit, !neg);
+ break;
+ }
+ }
+ /* Not found */
+ if (!trace_flags->opts[i].name)
+ return -EINVAL;
+
+ /* Refused to handle */
+ if (ret)
+ return ret;
+
+ if (neg)
+ trace_flags->val &= ~opts->bit;
+ else
+ trace_flags->val |= opts->bit;
+
+ return 0;
+}
+
static ssize_t
-tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf,
+tracing_trace_options_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
char buf[64];
char *cmp = buf;
int neg = 0;
+ int ret;
int i;
if (cnt >= sizeof(buf))
@@ -2258,11 +2834,13 @@ tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf,
break;
}
}
- /*
- * If no option could be set, return an error:
- */
- if (!trace_options[i])
- return -EINVAL;
+
+ /* If no option could be set, test the specific tracer options */
+ if (!trace_options[i]) {
+ ret = set_tracer_option(current_trace, cmp, neg);
+ if (ret)
+ return ret;
+ }
filp->f_pos += cnt;
@@ -2271,8 +2849,8 @@ tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf,
static struct file_operations tracing_iter_fops = {
.open = tracing_open_generic,
- .read = tracing_iter_ctrl_read,
- .write = tracing_iter_ctrl_write,
+ .read = tracing_trace_options_read,
+ .write = tracing_trace_options_write,
};
static const char readme_msg[] =
@@ -2286,9 +2864,9 @@ static const char readme_msg[] =
"# echo sched_switch > /debug/tracing/current_tracer\n"
"# cat /debug/tracing/current_tracer\n"
"sched_switch\n"
- "# cat /debug/tracing/iter_ctrl\n"
+ "# cat /debug/tracing/trace_options\n"
"noprint-parent nosym-offset nosym-addr noverbose\n"
- "# echo print-parent > /debug/tracing/iter_ctrl\n"
+ "# echo print-parent > /debug/tracing/trace_options\n"
"# echo 1 > /debug/tracing/tracing_enabled\n"
"# cat /debug/tracing/trace > /tmp/trace.txt\n"
"echo 0 > /debug/tracing/tracing_enabled\n"
@@ -2311,11 +2889,10 @@ static ssize_t
tracing_ctrl_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- struct trace_array *tr = filp->private_data;
char buf[64];
int r;
- r = sprintf(buf, "%ld\n", tr->ctrl);
+ r = sprintf(buf, "%u\n", tracer_enabled);
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
@@ -2343,16 +2920,18 @@ tracing_ctrl_write(struct file *filp, const char __user *ubuf,
val = !!val;
mutex_lock(&trace_types_lock);
- if (tr->ctrl ^ val) {
- if (val)
+ if (tracer_enabled ^ val) {
+ if (val) {
tracer_enabled = 1;
- else
+ if (current_trace->start)
+ current_trace->start(tr);
+ tracing_start();
+ } else {
tracer_enabled = 0;
-
- tr->ctrl = val;
-
- if (current_trace && current_trace->ctrl_update)
- current_trace->ctrl_update(tr);
+ tracing_stop();
+ if (current_trace->stop)
+ current_trace->stop(tr);
+ }
}
mutex_unlock(&trace_types_lock);
@@ -2378,29 +2957,11 @@ tracing_set_trace_read(struct file *filp, char __user *ubuf,
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
-static ssize_t
-tracing_set_trace_write(struct file *filp, const char __user *ubuf,
- size_t cnt, loff_t *ppos)
+static int tracing_set_tracer(char *buf)
{
struct trace_array *tr = &global_trace;
struct tracer *t;
- char buf[max_tracer_type_len+1];
- int i;
- size_t ret;
-
- ret = cnt;
-
- if (cnt > max_tracer_type_len)
- cnt = max_tracer_type_len;
-
- if (copy_from_user(&buf, ubuf, cnt))
- return -EFAULT;
-
- buf[cnt] = 0;
-
- /* strip ending whitespace. */
- for (i = cnt - 1; i > 0 && isspace(buf[i]); i--)
- buf[i] = 0;
+ int ret = 0;
mutex_lock(&trace_types_lock);
for (t = trace_types; t; t = t->next) {
@@ -2414,18 +2975,52 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf,
if (t == current_trace)
goto out;
+ trace_branch_disable();
if (current_trace && current_trace->reset)
current_trace->reset(tr);
current_trace = t;
- if (t->init)
- t->init(tr);
+ if (t->init) {
+ ret = t->init(tr);
+ if (ret)
+ goto out;
+ }
+ trace_branch_enable(tr);
out:
mutex_unlock(&trace_types_lock);
- if (ret > 0)
- filp->f_pos += ret;
+ return ret;
+}
+
+static ssize_t
+tracing_set_trace_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[max_tracer_type_len+1];
+ int i;
+ size_t ret;
+ int err;
+
+ ret = cnt;
+
+ if (cnt > max_tracer_type_len)
+ cnt = max_tracer_type_len;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ /* strip ending whitespace. */
+ for (i = cnt - 1; i > 0 && isspace(buf[i]); i--)
+ buf[i] = 0;
+
+ err = tracing_set_tracer(buf);
+ if (err)
+ return err;
+
+ filp->f_pos += ret;
return ret;
}
@@ -2492,6 +3087,10 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
return -ENOMEM;
mutex_lock(&trace_types_lock);
+
+ /* trace pipe does not show start of buffer */
+ cpus_setall(iter->started);
+
iter->tr = &global_trace;
iter->trace = current_trace;
filp->private_data = iter;
@@ -2667,7 +3266,7 @@ tracing_entries_read(struct file *filp, char __user *ubuf,
char buf[64];
int r;
- r = sprintf(buf, "%lu\n", tr->entries);
+ r = sprintf(buf, "%lu\n", tr->entries >> 10);
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
@@ -2678,7 +3277,6 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
unsigned long val;
char buf[64];
int ret, cpu;
- struct trace_array *tr = filp->private_data;
if (cnt >= sizeof(buf))
return -EINVAL;
@@ -2698,12 +3296,7 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
mutex_lock(&trace_types_lock);
- if (tr->ctrl) {
- cnt = -EBUSY;
- pr_info("ftrace: please disable tracing"
- " before modifying buffer size\n");
- goto out;
- }
+ tracing_stop();
/* disable all cpu buffers */
for_each_tracing_cpu(cpu) {
@@ -2713,6 +3306,9 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
atomic_inc(&max_tr.data[cpu]->disabled);
}
+ /* value is in KB */
+ val <<= 10;
+
if (val != global_trace.entries) {
ret = ring_buffer_resize(global_trace.buffer, val);
if (ret < 0) {
@@ -2751,6 +3347,7 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
atomic_dec(&max_tr.data[cpu]->disabled);
}
+ tracing_start();
max_tr.entries = global_trace.entries;
mutex_unlock(&trace_types_lock);
@@ -2762,7 +3359,7 @@ static int mark_printk(const char *fmt, ...)
int ret;
va_list args;
va_start(args, fmt);
- ret = trace_vprintk(0, fmt, args);
+ ret = trace_vprintk(0, -1, fmt, args);
va_end(args);
return ret;
}
@@ -2773,9 +3370,8 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
{
char *buf;
char *end;
- struct trace_array *tr = &global_trace;
- if (!tr->ctrl || tracing_disabled)
+ if (tracing_disabled)
return -EINVAL;
if (cnt > TRACE_BUF_SIZE)
@@ -2841,22 +3437,38 @@ static struct file_operations tracing_mark_fops = {
#ifdef CONFIG_DYNAMIC_FTRACE
+int __weak ftrace_arch_read_dyn_info(char *buf, int size)
+{
+ return 0;
+}
+
static ssize_t
-tracing_read_long(struct file *filp, char __user *ubuf,
+tracing_read_dyn_info(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
+ static char ftrace_dyn_info_buffer[1024];
+ static DEFINE_MUTEX(dyn_info_mutex);
unsigned long *p = filp->private_data;
- char buf[64];
+ char *buf = ftrace_dyn_info_buffer;
+ int size = ARRAY_SIZE(ftrace_dyn_info_buffer);
int r;
- r = sprintf(buf, "%ld\n", *p);
+ mutex_lock(&dyn_info_mutex);
+ r = sprintf(buf, "%ld ", *p);
- return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+ r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r);
+ buf[r++] = '\n';
+
+ r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+
+ mutex_unlock(&dyn_info_mutex);
+
+ return r;
}
-static struct file_operations tracing_read_long_fops = {
+static struct file_operations tracing_dyn_info_fops = {
.open = tracing_open_generic,
- .read = tracing_read_long,
+ .read = tracing_read_dyn_info,
};
#endif
@@ -2897,10 +3509,10 @@ static __init int tracer_init_debugfs(void)
if (!entry)
pr_warning("Could not create debugfs 'tracing_enabled' entry\n");
- entry = debugfs_create_file("iter_ctrl", 0644, d_tracer,
+ entry = debugfs_create_file("trace_options", 0644, d_tracer,
NULL, &tracing_iter_fops);
if (!entry)
- pr_warning("Could not create debugfs 'iter_ctrl' entry\n");
+ pr_warning("Could not create debugfs 'trace_options' entry\n");
entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer,
NULL, &tracing_cpumask_fops);
@@ -2950,11 +3562,11 @@ static __init int tracer_init_debugfs(void)
pr_warning("Could not create debugfs "
"'trace_pipe' entry\n");
- entry = debugfs_create_file("trace_entries", 0644, d_tracer,
+ entry = debugfs_create_file("buffer_size_kb", 0644, d_tracer,
&global_trace, &tracing_entries_fops);
if (!entry)
pr_warning("Could not create debugfs "
- "'trace_entries' entry\n");
+ "'buffer_size_kb' entry\n");
entry = debugfs_create_file("trace_marker", 0220, d_tracer,
NULL, &tracing_mark_fops);
@@ -2965,7 +3577,7 @@ static __init int tracer_init_debugfs(void)
#ifdef CONFIG_DYNAMIC_FTRACE
entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer,
&ftrace_update_tot_cnt,
- &tracing_read_long_fops);
+ &tracing_dyn_info_fops);
if (!entry)
pr_warning("Could not create debugfs "
"'dyn_ftrace_total_info' entry\n");
@@ -2976,7 +3588,7 @@ static __init int tracer_init_debugfs(void)
return 0;
}
-int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
+int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args)
{
static DEFINE_SPINLOCK(trace_buf_lock);
static char trace_buf[TRACE_BUF_SIZE];
@@ -2984,11 +3596,11 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
struct ring_buffer_event *event;
struct trace_array *tr = &global_trace;
struct trace_array_cpu *data;
- struct print_entry *entry;
- unsigned long flags, irq_flags;
int cpu, len = 0, size, pc;
+ struct print_entry *entry;
+ unsigned long irq_flags;
- if (!tr->ctrl || tracing_disabled)
+ if (tracing_disabled || tracing_selftest_running)
return 0;
pc = preempt_count();
@@ -2999,7 +3611,8 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
if (unlikely(atomic_read(&data->disabled)))
goto out;
- spin_lock_irqsave(&trace_buf_lock, flags);
+ pause_graph_tracing();
+ spin_lock_irqsave(&trace_buf_lock, irq_flags);
len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args);
len = min(len, TRACE_BUF_SIZE-1);
@@ -3010,17 +3623,18 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
if (!event)
goto out_unlock;
entry = ring_buffer_event_data(event);
- tracing_generic_entry_update(&entry->ent, flags, pc);
+ tracing_generic_entry_update(&entry->ent, irq_flags, pc);
entry->ent.type = TRACE_PRINT;
entry->ip = ip;
+ entry->depth = depth;
memcpy(&entry->buf, trace_buf, len);
entry->buf[len] = 0;
ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
out_unlock:
- spin_unlock_irqrestore(&trace_buf_lock, flags);
-
+ spin_unlock_irqrestore(&trace_buf_lock, irq_flags);
+ unpause_graph_tracing();
out:
preempt_enable_notrace();
@@ -3037,7 +3651,7 @@ int __ftrace_printk(unsigned long ip, const char *fmt, ...)
return 0;
va_start(ap, fmt);
- ret = trace_vprintk(ip, fmt, ap);
+ ret = trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap);
va_end(ap);
return ret;
}
@@ -3046,7 +3660,8 @@ EXPORT_SYMBOL_GPL(__ftrace_printk);
static int trace_panic_handler(struct notifier_block *this,
unsigned long event, void *unused)
{
- ftrace_dump();
+ if (ftrace_dump_on_oops)
+ ftrace_dump();
return NOTIFY_OK;
}
@@ -3062,7 +3677,8 @@ static int trace_die_handler(struct notifier_block *self,
{
switch (val) {
case DIE_OOPS:
- ftrace_dump();
+ if (ftrace_dump_on_oops)
+ ftrace_dump();
break;
default:
break;
@@ -3103,7 +3719,6 @@ trace_printk_seq(struct trace_seq *s)
trace_seq_reset(s);
}
-
void ftrace_dump(void)
{
static DEFINE_SPINLOCK(ftrace_dump_lock);
@@ -3128,6 +3743,9 @@ void ftrace_dump(void)
atomic_inc(&global_trace.data[cpu]->disabled);
}
+ /* don't look at user memory in panic mode */
+ trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
+
printk(KERN_TRACE "Dumping ftrace buffer:\n");
iter.tr = &global_trace;
@@ -3221,7 +3839,6 @@ __init static int tracer_alloc_buffers(void)
#endif
/* All seems OK, enable tracing */
- global_trace.ctrl = tracer_enabled;
tracing_disabled = 0;
atomic_notifier_chain_register(&panic_notifier_list,
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-27 09:47:06 +0000