Merge branch 'tip/perf/core-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull minor tracing updates and fixes from Steven Rostedt:
 "It seems that one of my old pull requests have slipped through.

  The changes are contained to just the files that I maintain, and are
  changes from others that I told I would get into this merge window.

  They have already been in linux-next for several weeks, and should be
  well tested."

* 'tip/perf/core-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Remove unnecessary WARN_ONCE's from tracing_buffers_splice_read
  tracing: Remove unneeded checks from the stack tracer
  tracing: Add a resize function to make one buffer equivalent to another buffer
This commit is contained in:
Linus Torvalds 2012-12-18 12:28:39 -08:00
commit 758338e960
2 changed files with 31 additions and 33 deletions

View File

@ -3034,6 +3034,31 @@ static void set_buffer_entries(struct trace_array *tr, unsigned long val)
tr->data[cpu]->entries = val;
}
/* resize @tr's buffer to the size of @size_tr's entries */
static int resize_buffer_duplicate_size(struct trace_array *tr,
struct trace_array *size_tr, int cpu_id)
{
int cpu, ret = 0;
if (cpu_id == RING_BUFFER_ALL_CPUS) {
for_each_tracing_cpu(cpu) {
ret = ring_buffer_resize(tr->buffer,
size_tr->data[cpu]->entries, cpu);
if (ret < 0)
break;
tr->data[cpu]->entries = size_tr->data[cpu]->entries;
}
} else {
ret = ring_buffer_resize(tr->buffer,
size_tr->data[cpu_id]->entries, cpu_id);
if (ret == 0)
tr->data[cpu_id]->entries =
size_tr->data[cpu_id]->entries;
}
return ret;
}
static int __tracing_resize_ring_buffer(unsigned long size, int cpu)
{
int ret;
@ -3058,23 +3083,8 @@ static int __tracing_resize_ring_buffer(unsigned long size, int cpu)
ret = ring_buffer_resize(max_tr.buffer, size, cpu);
if (ret < 0) {
int r = 0;
if (cpu == RING_BUFFER_ALL_CPUS) {
int i;
for_each_tracing_cpu(i) {
r = ring_buffer_resize(global_trace.buffer,
global_trace.data[i]->entries,
i);
if (r < 0)
break;
}
} else {
r = ring_buffer_resize(global_trace.buffer,
global_trace.data[cpu]->entries,
cpu);
}
int r = resize_buffer_duplicate_size(&global_trace,
&global_trace, cpu);
if (r < 0) {
/*
* AARGH! We are left with different
@ -3212,17 +3222,11 @@ static int tracing_set_tracer(const char *buf)
topts = create_trace_option_files(t);
if (t->use_max_tr) {
int cpu;
/* we need to make per cpu buffer sizes equivalent */
for_each_tracing_cpu(cpu) {
ret = ring_buffer_resize(max_tr.buffer,
global_trace.data[cpu]->entries,
cpu);
if (ret < 0)
goto out;
max_tr.data[cpu]->entries =
global_trace.data[cpu]->entries;
}
ret = resize_buffer_duplicate_size(&max_tr, &global_trace,
RING_BUFFER_ALL_CPUS);
if (ret < 0)
goto out;
}
if (t->init) {
@ -4271,13 +4275,11 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
return -ENOMEM;
if (*ppos & (PAGE_SIZE - 1)) {
WARN_ONCE(1, "Ftrace: previous read must page-align\n");
ret = -EINVAL;
goto out;
}
if (len & (PAGE_SIZE - 1)) {
WARN_ONCE(1, "Ftrace: splice_read should page-align\n");
if (len < PAGE_SIZE) {
ret = -EINVAL;
goto out;

View File

@ -33,7 +33,6 @@ static unsigned long max_stack_size;
static arch_spinlock_t max_stack_lock =
(arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
static int stack_trace_disabled __read_mostly;
static DEFINE_PER_CPU(int, trace_active);
static DEFINE_MUTEX(stack_sysctl_mutex);
@ -116,9 +115,6 @@ stack_trace_call(unsigned long ip, unsigned long parent_ip,
{
int cpu;
if (unlikely(!ftrace_enabled || stack_trace_disabled))
return;
preempt_disable_notrace();
cpu = raw_smp_processor_id();