tracing: Consolidate buffer allocation code

There's a bit of duplicate code in creating the trace buffers for
the normal trace buffer and the max trace buffer among the instances
and the main global_trace. This code can be consolidated and cleaned
up a bit making the code cleaner and more readable as well as less
duplication.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Red Hat) 2013-03-05 21:13:47 -05:00 committed by Steven Rostedt
parent 45ad21ca55
commit 737223fbca

View file

@ -3171,6 +3171,7 @@ int tracer_init(struct tracer *t, struct trace_array *tr)
static void set_buffer_entries(struct trace_buffer *buf, unsigned long val)
{
int cpu;
for_each_tracing_cpu(cpu)
per_cpu_ptr(buf->data, cpu)->entries = val;
}
@ -5267,12 +5268,70 @@ struct dentry *trace_instance_dir;
static void
init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer);
static int new_instance_create(const char *name)
static void init_trace_buffers(struct trace_array *tr, struct trace_buffer *buf)
{
int cpu;
for_each_tracing_cpu(cpu) {
memset(per_cpu_ptr(buf->data, cpu), 0, sizeof(struct trace_array_cpu));
per_cpu_ptr(buf->data, cpu)->trace_cpu.cpu = cpu;
per_cpu_ptr(buf->data, cpu)->trace_cpu.tr = tr;
}
}
static int allocate_trace_buffers(struct trace_array *tr, int size)
{
enum ring_buffer_flags rb_flags;
rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0;
tr->trace_buffer.buffer = ring_buffer_alloc(size, rb_flags);
if (!tr->trace_buffer.buffer)
goto out_free;
tr->trace_buffer.data = alloc_percpu(struct trace_array_cpu);
if (!tr->trace_buffer.data)
goto out_free;
init_trace_buffers(tr, &tr->trace_buffer);
/* Allocate the first page for all buffers */
set_buffer_entries(&tr->trace_buffer,
ring_buffer_size(tr->trace_buffer.buffer, 0));
#ifdef CONFIG_TRACER_MAX_TRACE
tr->max_buffer.buffer = ring_buffer_alloc(1, rb_flags);
if (!tr->max_buffer.buffer)
goto out_free;
tr->max_buffer.data = alloc_percpu(struct trace_array_cpu);
if (!tr->max_buffer.data)
goto out_free;
init_trace_buffers(tr, &tr->max_buffer);
set_buffer_entries(&tr->max_buffer, 1);
#endif
return 0;
out_free:
if (tr->trace_buffer.buffer)
ring_buffer_free(tr->trace_buffer.buffer);
free_percpu(tr->trace_buffer.data);
#ifdef CONFIG_TRACER_MAX_TRACE
if (tr->max_buffer.buffer)
ring_buffer_free(tr->max_buffer.buffer);
free_percpu(tr->max_buffer.data);
#endif
return -ENOMEM;
}
static int new_instance_create(const char *name)
{
struct trace_array *tr;
int ret;
int i;
mutex_lock(&trace_types_lock);
@ -5298,22 +5357,9 @@ static int new_instance_create(const char *name)
INIT_LIST_HEAD(&tr->systems);
INIT_LIST_HEAD(&tr->events);
rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0;
tr->trace_buffer.buffer = ring_buffer_alloc(trace_buf_size, rb_flags);
if (!tr->trace_buffer.buffer)
if (allocate_trace_buffers(tr, trace_buf_size) < 0)
goto out_free_tr;
tr->trace_buffer.data = alloc_percpu(struct trace_array_cpu);
if (!tr->trace_buffer.data)
goto out_free_tr;
for_each_tracing_cpu(i) {
memset(per_cpu_ptr(tr->trace_buffer.data, i), 0, sizeof(struct trace_array_cpu));
per_cpu_ptr(tr->trace_buffer.data, i)->trace_cpu.cpu = i;
per_cpu_ptr(tr->trace_buffer.data, i)->trace_cpu.tr = tr;
}
/* Holder for file callbacks */
tr->trace_cpu.cpu = RING_BUFFER_ALL_CPUS;
tr->trace_cpu.tr = tr;
@ -5736,8 +5782,6 @@ EXPORT_SYMBOL_GPL(ftrace_dump);
__init static int tracer_alloc_buffers(void)
{
int ring_buf_size;
enum ring_buffer_flags rb_flags;
int i;
int ret = -ENOMEM;
@ -5758,69 +5802,21 @@ __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);
raw_spin_lock_init(&global_trace.start_lock);
/* TODO: make the number of buffers hot pluggable with CPUS */
global_trace.trace_buffer.buffer = ring_buffer_alloc(ring_buf_size, rb_flags);
if (!global_trace.trace_buffer.buffer) {
if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) {
printk(KERN_ERR "tracer: failed to allocate ring buffer!\n");
WARN_ON(1);
goto out_free_cpumask;
}
global_trace.trace_buffer.data = alloc_percpu(struct trace_array_cpu);
if (!global_trace.trace_buffer.data) {
printk(KERN_ERR "tracer: failed to allocate percpu memory!\n");
WARN_ON(1);
goto out_free_cpumask;
}
for_each_tracing_cpu(i) {
memset(per_cpu_ptr(global_trace.trace_buffer.data, i), 0,
sizeof(struct trace_array_cpu));
per_cpu_ptr(global_trace.trace_buffer.data, i)->trace_cpu.cpu = i;
per_cpu_ptr(global_trace.trace_buffer.data, i)->trace_cpu.tr = &global_trace;
}
if (global_trace.buffer_disabled)
tracing_off();
#ifdef CONFIG_TRACER_MAX_TRACE
global_trace.max_buffer.data = alloc_percpu(struct trace_array_cpu);
if (!global_trace.max_buffer.data) {
printk(KERN_ERR "tracer: failed to allocate percpu memory!\n");
WARN_ON(1);
goto out_free_cpumask;
}
global_trace.max_buffer.buffer = ring_buffer_alloc(1, rb_flags);
if (!global_trace.max_buffer.buffer) {
printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n");
WARN_ON(1);
ring_buffer_free(global_trace.trace_buffer.buffer);
goto out_free_cpumask;
}
for_each_tracing_cpu(i) {
memset(per_cpu_ptr(global_trace.max_buffer.data, i), 0,
sizeof(struct trace_array_cpu));
per_cpu_ptr(global_trace.max_buffer.data, i)->trace_cpu.cpu = i;
per_cpu_ptr(global_trace.max_buffer.data, i)->trace_cpu.tr = &global_trace;
}
#endif
/* Allocate the first page for all buffers */
set_buffer_entries(&global_trace.trace_buffer,
ring_buffer_size(global_trace.trace_buffer.buffer, 0));
#ifdef CONFIG_TRACER_MAX_TRACE
set_buffer_entries(&global_trace.max_buffer, 1);
#endif
trace_init_cmdlines();
register_tracer(&nop_trace);