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Diffstat (limited to 'kernel/trace/trace.c')
-rw-r--r--kernel/trace/trace.c38
1 files changed, 27 insertions, 11 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index dc53ecb8058..9541c27c1cf 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -41,8 +41,6 @@
#include "trace.h"
#include "trace_output.h"
-#define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE)
-
/*
* On boot up, the ring buffer is set to the minimum size, so that
* we do not waste memory on systems that are not using tracing.
@@ -340,7 +338,7 @@ static DECLARE_WAIT_QUEUE_HEAD(trace_wait);
/* trace_flags holds trace_options default values */
unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME |
- TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD;
+ TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE;
static int trace_stop_count;
static DEFINE_SPINLOCK(tracing_start_lock);
@@ -425,6 +423,7 @@ static const char *trace_options[] = {
"sleep-time",
"graph-time",
"record-cmd",
+ "overwrite",
NULL
};
@@ -780,6 +779,11 @@ __acquires(kernel_lock)
tracing_reset_online_cpus(tr);
current_trace = type;
+
+ /* If we expanded the buffers, make sure the max is expanded too */
+ if (ring_buffer_expanded && type->use_max_tr)
+ ring_buffer_resize(max_tr.buffer, trace_buf_size);
+
/* the test is responsible for initializing and enabling */
pr_info("Testing tracer %s: ", type->name);
ret = type->selftest(type, tr);
@@ -792,6 +796,10 @@ __acquires(kernel_lock)
/* Only reset on passing, to avoid touching corrupted buffers */
tracing_reset_online_cpus(tr);
+ /* Shrink the max buffer again */
+ if (ring_buffer_expanded && type->use_max_tr)
+ ring_buffer_resize(max_tr.buffer, 1);
+
printk(KERN_CONT "PASSED\n");
}
#endif
@@ -1102,7 +1110,6 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
entry->preempt_count = pc & 0xff;
entry->pid = (tsk) ? tsk->pid : 0;
- entry->lock_depth = (tsk) ? tsk->lock_depth : 0;
entry->flags =
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
@@ -1749,10 +1756,9 @@ static void print_lat_help_header(struct seq_file *m)
seq_puts(m, "# | / _----=> need-resched \n");
seq_puts(m, "# || / _---=> hardirq/softirq \n");
seq_puts(m, "# ||| / _--=> preempt-depth \n");
- seq_puts(m, "# |||| /_--=> lock-depth \n");
- seq_puts(m, "# |||||/ delay \n");
- seq_puts(m, "# cmd pid |||||| time | caller \n");
- seq_puts(m, "# \\ / |||||| \\ | / \n");
+ seq_puts(m, "# |||| / delay \n");
+ seq_puts(m, "# cmd pid ||||| time | caller \n");
+ seq_puts(m, "# \\ / ||||| \\ | / \n");
}
static void print_func_help_header(struct seq_file *m)
@@ -2529,6 +2535,9 @@ static void set_tracer_flags(unsigned int mask, int enabled)
if (mask == TRACE_ITER_RECORD_CMD)
trace_event_enable_cmd_record(enabled);
+
+ if (mask == TRACE_ITER_OVERWRITE)
+ ring_buffer_change_overwrite(global_trace.buffer, enabled);
}
static ssize_t
@@ -2710,6 +2719,10 @@ tracing_ctrl_write(struct file *filp, const char __user *ubuf,
mutex_lock(&trace_types_lock);
if (tracer_enabled ^ val) {
+
+ /* Only need to warn if this is used to change the state */
+ WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on");
+
if (val) {
tracer_enabled = 1;
if (current_trace->start)
@@ -4551,9 +4564,11 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode)
__init static int tracer_alloc_buffers(void)
{
int ring_buf_size;
+ enum ring_buffer_flags rb_flags;
int i;
int ret = -ENOMEM;
+
if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL))
goto out;
@@ -4566,12 +4581,13 @@ __init static int tracer_alloc_buffers(void)
else
ring_buf_size = 1;
+ rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0;
+
cpumask_copy(tracing_buffer_mask, cpu_possible_mask);
cpumask_copy(tracing_cpumask, cpu_all_mask);
/* TODO: make the number of buffers hot pluggable with CPUS */
- global_trace.buffer = ring_buffer_alloc(ring_buf_size,
- TRACE_BUFFER_FLAGS);
+ global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags);
if (!global_trace.buffer) {
printk(KERN_ERR "tracer: failed to allocate ring buffer!\n");
WARN_ON(1);
@@ -4581,7 +4597,7 @@ __init static int tracer_alloc_buffers(void)
#ifdef CONFIG_TRACER_MAX_TRACE
- max_tr.buffer = ring_buffer_alloc(1, TRACE_BUFFER_FLAGS);
+ max_tr.buffer = ring_buffer_alloc(1, rb_flags);
if (!max_tr.buffer) {
printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n");
WARN_ON(1);