[for-next][PATCH 1/8] ftrace: Remove global function list and call function directly

From: Steven Rostedt
Date: Thu Apr 24 2014 - 12:04:01 EST

From: "Steven Rostedt (Red Hat)" <rostedt@xxxxxxxxxxx>

Instead of having a list of global functions that are called,
as only one global function is allow to be enabled at a time, there's
no reason to have a list.

Instead, simply have all the users of the global ops, use the global ops
directly, instead of registering their own ftrace_ops. Just switch what
function is used before enabling the function tracer.

This removes a lot of code as well as the complexity involved with it.

Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
---
include/linux/ftrace.h | 20 ++---
kernel/trace/ftrace.c | 152 +++++++++++---------------------------
kernel/trace/trace.c | 2 +
kernel/trace/trace.h | 19 +++--
kernel/trace/trace_functions.c | 55 +++++---------
kernel/trace/trace_irqsoff.c | 33 ++++-----
kernel/trace/trace_sched_wakeup.c | 40 +++++-----
kernel/trace/trace_selftest.c | 33 +++++----
8 files changed, 133 insertions(+), 221 deletions(-)

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 9212b01..f0ff2c2 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -62,9 +62,6 @@ typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
* set in the flags member.
*
* ENABLED - set/unset when ftrace_ops is registered/unregistered
- * GLOBAL - set manualy by ftrace_ops user to denote the ftrace_ops
- * is part of the global tracers sharing the same filter
- * via set_ftrace_* debugfs files.
* DYNAMIC - set when ftrace_ops is registered to denote dynamically
* allocated ftrace_ops which need special care
* CONTROL - set manualy by ftrace_ops user to denote the ftrace_ops
@@ -96,15 +93,14 @@ typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
*/
enum {
FTRACE_OPS_FL_ENABLED = 1 << 0,
- FTRACE_OPS_FL_GLOBAL = 1 << 1,
- FTRACE_OPS_FL_DYNAMIC = 1 << 2,
- FTRACE_OPS_FL_CONTROL = 1 << 3,
- FTRACE_OPS_FL_SAVE_REGS = 1 << 4,
- FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 5,
- FTRACE_OPS_FL_RECURSION_SAFE = 1 << 6,
- FTRACE_OPS_FL_STUB = 1 << 7,
- FTRACE_OPS_FL_INITIALIZED = 1 << 8,
- FTRACE_OPS_FL_DELETED = 1 << 9,
+ FTRACE_OPS_FL_DYNAMIC = 1 << 1,
+ FTRACE_OPS_FL_CONTROL = 1 << 2,
+ FTRACE_OPS_FL_SAVE_REGS = 1 << 3,
+ FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 4,
+ FTRACE_OPS_FL_RECURSION_SAFE = 1 << 5,
+ FTRACE_OPS_FL_STUB = 1 << 6,
+ FTRACE_OPS_FL_INITIALIZED = 1 << 7,
+ FTRACE_OPS_FL_DELETED = 1 << 8,
};

/*
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 1fd4b94..8f61ef7 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -62,7 +62,7 @@
#define FTRACE_HASH_DEFAULT_BITS 10
#define FTRACE_HASH_MAX_BITS 12

-#define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_CONTROL)
+#define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_CONTROL)

#ifdef CONFIG_DYNAMIC_FTRACE
#define INIT_REGEX_LOCK(opsname) \
@@ -103,7 +103,6 @@ static int ftrace_disabled __read_mostly;

static DEFINE_MUTEX(ftrace_lock);

-static struct ftrace_ops *ftrace_global_list __read_mostly = &ftrace_list_end;
static struct ftrace_ops *ftrace_control_list __read_mostly = &ftrace_list_end;
static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end;
ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
@@ -171,23 +170,6 @@ int ftrace_nr_registered_ops(void)
return cnt;
}

-static void
-ftrace_global_list_func(unsigned long ip, unsigned long parent_ip,
- struct ftrace_ops *op, struct pt_regs *regs)
-{
- int bit;
-
- bit = trace_test_and_set_recursion(TRACE_GLOBAL_START, TRACE_GLOBAL_MAX);
- if (bit < 0)
- return;
-
- do_for_each_ftrace_op(op, ftrace_global_list) {
- op->func(ip, parent_ip, op, regs);
- } while_for_each_ftrace_op(op);
-
- trace_clear_recursion(bit);
-}
-
static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *regs)
{
@@ -237,43 +219,6 @@ static int control_ops_alloc(struct ftrace_ops *ops)
return 0;
}

-static void update_global_ops(void)
-{
- ftrace_func_t func = ftrace_global_list_func;
- void *private = NULL;
-
- /* The list has its own recursion protection. */
- global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
-
- /*
- * If there's only one function registered, then call that
- * function directly. Otherwise, we need to iterate over the
- * registered callers.
- */
- if (ftrace_global_list == &ftrace_list_end ||
- ftrace_global_list->next == &ftrace_list_end) {
- func = ftrace_global_list->func;
- private = ftrace_global_list->private;
- /*
- * As we are calling the function directly.
- * If it does not have recursion protection,
- * the function_trace_op needs to be updated
- * accordingly.
- */
- if (!(ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE))
- global_ops.flags &= ~FTRACE_OPS_FL_RECURSION_SAFE;
- }
-
- /* If we filter on pids, update to use the pid function */
- if (!list_empty(&ftrace_pids)) {
- set_ftrace_pid_function(func);
- func = ftrace_pid_func;
- }
-
- global_ops.func = func;
- global_ops.private = private;
-}
-
static void ftrace_sync(struct work_struct *work)
{
/*
@@ -301,8 +246,6 @@ static void update_ftrace_function(void)
{
ftrace_func_t func;

- update_global_ops();
-
/*
* If we are at the end of the list and this ops is
* recursion safe and not dynamic and the arch supports passing ops,
@@ -314,10 +257,7 @@ static void update_ftrace_function(void)
(ftrace_ops_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) &&
!FTRACE_FORCE_LIST_FUNC)) {
/* Set the ftrace_ops that the arch callback uses */
- if (ftrace_ops_list == &global_ops)
- set_function_trace_op = ftrace_global_list;
- else
- set_function_trace_op = ftrace_ops_list;
+ set_function_trace_op = ftrace_ops_list;
func = ftrace_ops_list->func;
} else {
/* Just use the default ftrace_ops */
@@ -434,16 +374,9 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
if (ops->flags & FTRACE_OPS_FL_DELETED)
return -EINVAL;

- if (FTRACE_WARN_ON(ops == &global_ops))
- return -EINVAL;
-
if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED))
return -EBUSY;

- /* We don't support both control and global flags set. */
- if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK)
- return -EINVAL;
-
#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS
/*
* If the ftrace_ops specifies SAVE_REGS, then it only can be used
@@ -461,10 +394,7 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
if (!core_kernel_data((unsigned long)ops))
ops->flags |= FTRACE_OPS_FL_DYNAMIC;

- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- add_ftrace_list_ops(&ftrace_global_list, &global_ops, ops);
- ops->flags |= FTRACE_OPS_FL_ENABLED;
- } else if (ops->flags & FTRACE_OPS_FL_CONTROL) {
+ if (ops->flags & FTRACE_OPS_FL_CONTROL) {
if (control_ops_alloc(ops))
return -ENOMEM;
add_ftrace_list_ops(&ftrace_control_list, &control_ops, ops);
@@ -484,15 +414,7 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED)))
return -EBUSY;

- if (FTRACE_WARN_ON(ops == &global_ops))
- return -EINVAL;
-
- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- ret = remove_ftrace_list_ops(&ftrace_global_list,
- &global_ops, ops);
- if (!ret)
- ops->flags &= ~FTRACE_OPS_FL_ENABLED;
- } else if (ops->flags & FTRACE_OPS_FL_CONTROL) {
+ if (ops->flags & FTRACE_OPS_FL_CONTROL) {
ret = remove_ftrace_list_ops(&ftrace_control_list,
&control_ops, ops);
} else
@@ -2128,15 +2050,6 @@ static int ftrace_startup(struct ftrace_ops *ops, int command)
ftrace_start_up++;
command |= FTRACE_UPDATE_CALLS;

- /* ops marked global share the filter hashes */
- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- ops = &global_ops;
- /* Don't update hash if global is already set */
- if (global_start_up)
- hash_enable = false;
- global_start_up++;
- }
-
ops->flags |= FTRACE_OPS_FL_ENABLED;
if (hash_enable)
ftrace_hash_rec_enable(ops, 1);
@@ -2166,21 +2079,10 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command)
*/
WARN_ON_ONCE(ftrace_start_up < 0);

- if (ops->flags & FTRACE_OPS_FL_GLOBAL) {
- ops = &global_ops;
- global_start_up--;
- WARN_ON_ONCE(global_start_up < 0);
- /* Don't update hash if global still has users */
- if (global_start_up) {
- WARN_ON_ONCE(!ftrace_start_up);
- hash_disable = false;
- }
- }
-
if (hash_disable)
ftrace_hash_rec_disable(ops, 1);

- if (ops != &global_ops || !global_start_up)
+ if (!global_start_up)
ops->flags &= ~FTRACE_OPS_FL_ENABLED;

command |= FTRACE_UPDATE_CALLS;
@@ -3524,10 +3426,6 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
struct ftrace_hash *hash;
int ret;

- /* All global ops uses the global ops filters */
- if (ops->flags & FTRACE_OPS_FL_GLOBAL)
- ops = &global_ops;
-
if (unlikely(ftrace_disabled))
return -ENODEV;

@@ -4462,6 +4360,34 @@ ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs)

#endif /* CONFIG_DYNAMIC_FTRACE */

+__init void ftrace_init_global_array_ops(struct trace_array *tr)
+{
+ tr->ops = &global_ops;
+ tr->ops->private = tr;
+}
+
+void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func)
+{
+ /* If we filter on pids, update to use the pid function */
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL) {
+ if (WARN_ON(tr->ops->func != ftrace_stub))
+ printk("ftrace ops had %pS for function\n",
+ tr->ops->func);
+ /* Only the top level instance does pid tracing */
+ if (!list_empty(&ftrace_pids)) {
+ set_ftrace_pid_function(func);
+ func = ftrace_pid_func;
+ }
+ }
+ tr->ops->func = func;
+ tr->ops->private = tr;
+}
+
+void ftrace_reset_array_ops(struct trace_array *tr)
+{
+ tr->ops->func = ftrace_stub;
+}
+
static void
ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *regs)
@@ -4520,9 +4446,16 @@ __ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
*/
preempt_disable_notrace();
do_for_each_ftrace_op(op, ftrace_ops_list) {
- if (ftrace_ops_test(op, ip, regs))
+ if (ftrace_ops_test(op, ip, regs)) {
+ if (WARN_ON(!op->func)) {
+ function_trace_stop = 1;
+ printk("op=%p %pS\n", op, op);
+ goto out;
+ }
op->func(ip, parent_ip, op, regs);
+ }
} while_for_each_ftrace_op(op);
+out:
preempt_enable_notrace();
trace_clear_recursion(bit);
}
@@ -5076,8 +5009,7 @@ ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state,
/* Just a place holder for function graph */
static struct ftrace_ops fgraph_ops __read_mostly = {
.func = ftrace_stub,
- .flags = FTRACE_OPS_FL_STUB | FTRACE_OPS_FL_GLOBAL |
- FTRACE_OPS_FL_RECURSION_SAFE,
+ .flags = FTRACE_OPS_FL_STUB | FTRACE_OPS_FL_RECURSION_SAFE,
};

static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 737b0ef..fdd33aa 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -6629,6 +6629,8 @@ __init static int tracer_alloc_buffers(void)
*/
global_trace.current_trace = &nop_trace;

+ ftrace_init_global_array_ops(&global_trace);
+
register_tracer(&nop_trace);

/* All seems OK, enable tracing */
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 2e29d7b..df5256b 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -416,13 +416,7 @@ enum {
TRACE_FTRACE_IRQ_BIT,
TRACE_FTRACE_SIRQ_BIT,

- /* GLOBAL_BITs must be greater than FTRACE_BITs */
- TRACE_GLOBAL_BIT,
- TRACE_GLOBAL_NMI_BIT,
- TRACE_GLOBAL_IRQ_BIT,
- TRACE_GLOBAL_SIRQ_BIT,
-
- /* INTERNAL_BITs must be greater than GLOBAL_BITs */
+ /* INTERNAL_BITs must be greater than FTRACE_BITs */
TRACE_INTERNAL_BIT,
TRACE_INTERNAL_NMI_BIT,
TRACE_INTERNAL_IRQ_BIT,
@@ -449,9 +443,6 @@ enum {
#define TRACE_FTRACE_START TRACE_FTRACE_BIT
#define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)

-#define TRACE_GLOBAL_START TRACE_GLOBAL_BIT
-#define TRACE_GLOBAL_MAX ((1 << (TRACE_GLOBAL_START + TRACE_CONTEXT_BITS)) - 1)
-
#define TRACE_LIST_START TRACE_INTERNAL_BIT
#define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)

@@ -823,6 +814,9 @@ extern int ftrace_is_dead(void);
int ftrace_create_function_files(struct trace_array *tr,
struct dentry *parent);
void ftrace_destroy_function_files(struct trace_array *tr);
+void ftrace_init_global_array_ops(struct trace_array *tr);
+void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
+void ftrace_reset_array_ops(struct trace_array *tr);
#else
static inline int ftrace_trace_task(struct task_struct *task)
{
@@ -836,6 +830,11 @@ ftrace_create_function_files(struct trace_array *tr,
return 0;
}
static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
+static inline __init void
+ftrace_init_global_array_ops(struct trace_array *tr) { }
+static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
+/* ftace_func_t type is not defined, use macro instead of static inline */
+#define ftrace_init_array_ops(tr, func) do { } while (0)
#endif /* CONFIG_FUNCTION_TRACER */

#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index ffd5635..2d9482b 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -26,8 +26,6 @@ function_trace_call(unsigned long ip, unsigned long parent_ip,
static void
function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *pt_regs);
-static struct ftrace_ops trace_ops;
-static struct ftrace_ops trace_stack_ops;
static struct tracer_flags func_flags;

/* Our option */
@@ -83,28 +81,24 @@ void ftrace_destroy_function_files(struct trace_array *tr)

static int function_trace_init(struct trace_array *tr)
{
- struct ftrace_ops *ops;
-
- if (tr->flags & TRACE_ARRAY_FL_GLOBAL) {
- /* There's only one global tr */
- if (!trace_ops.private) {
- trace_ops.private = tr;
- trace_stack_ops.private = tr;
- }
+ ftrace_func_t func;

- if (func_flags.val & TRACE_FUNC_OPT_STACK)
- ops = &trace_stack_ops;
- else
- ops = &trace_ops;
- tr->ops = ops;
- } else if (!tr->ops) {
- /*
- * Instance trace_arrays get their ops allocated
- * at instance creation. Unless it failed
- * the allocation.
- */
+ /*
+ * Instance trace_arrays get their ops allocated
+ * at instance creation. Unless it failed
+ * the allocation.
+ */
+ if (!tr->ops)
return -ENOMEM;
- }
+
+ /* Currently only the global instance can do stack tracing */
+ if (tr->flags & TRACE_ARRAY_FL_GLOBAL &&
+ func_flags.val & TRACE_FUNC_OPT_STACK)
+ func = function_stack_trace_call;
+ else
+ func = function_trace_call;
+
+ ftrace_init_array_ops(tr, func);

tr->trace_buffer.cpu = get_cpu();
put_cpu();
@@ -118,6 +112,7 @@ static void function_trace_reset(struct trace_array *tr)
{
tracing_stop_function_trace(tr);
tracing_stop_cmdline_record();
+ ftrace_reset_array_ops(tr);
}

static void function_trace_start(struct trace_array *tr)
@@ -199,18 +194,6 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
local_irq_restore(flags);
}

-static struct ftrace_ops trace_ops __read_mostly =
-{
- .func = function_trace_call,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
-
-static struct ftrace_ops trace_stack_ops __read_mostly =
-{
- .func = function_stack_trace_call,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
-
static struct tracer_opt func_opts[] = {
#ifdef CONFIG_STACKTRACE
{ TRACER_OPT(func_stack_trace, TRACE_FUNC_OPT_STACK) },
@@ -248,10 +231,10 @@ func_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
unregister_ftrace_function(tr->ops);

if (set) {
- tr->ops = &trace_stack_ops;
+ tr->ops->func = function_stack_trace_call;
register_ftrace_function(tr->ops);
} else {
- tr->ops = &trace_ops;
+ tr->ops->func = function_trace_call;
register_ftrace_function(tr->ops);
}

diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 8ff02cb..b5cb047 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -151,12 +151,6 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip,

atomic_dec(&data->disabled);
}
-
-static struct ftrace_ops trace_ops __read_mostly =
-{
- .func = irqsoff_tracer_call,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
#endif /* CONFIG_FUNCTION_TRACER */

#ifdef CONFIG_FUNCTION_GRAPH_TRACER
@@ -531,7 +525,7 @@ void trace_preempt_off(unsigned long a0, unsigned long a1)
}
#endif /* CONFIG_PREEMPT_TRACER */

-static int register_irqsoff_function(int graph, int set)
+static int register_irqsoff_function(struct trace_array *tr, int graph, int set)
{
int ret;

@@ -543,7 +537,7 @@ static int register_irqsoff_function(int graph, int set)
ret = register_ftrace_graph(&irqsoff_graph_return,
&irqsoff_graph_entry);
else
- ret = register_ftrace_function(&trace_ops);
+ ret = register_ftrace_function(tr->ops);

if (!ret)
function_enabled = true;
@@ -551,7 +545,7 @@ static int register_irqsoff_function(int graph, int set)
return ret;
}

-static void unregister_irqsoff_function(int graph)
+static void unregister_irqsoff_function(struct trace_array *tr, int graph)
{
if (!function_enabled)
return;
@@ -559,17 +553,17 @@ static void unregister_irqsoff_function(int graph)
if (graph)
unregister_ftrace_graph();
else
- unregister_ftrace_function(&trace_ops);
+ unregister_ftrace_function(tr->ops);

function_enabled = false;
}

-static void irqsoff_function_set(int set)
+static void irqsoff_function_set(struct trace_array *tr, int set)
{
if (set)
- register_irqsoff_function(is_graph(), 1);
+ register_irqsoff_function(tr, is_graph(), 1);
else
- unregister_irqsoff_function(is_graph());
+ unregister_irqsoff_function(tr, is_graph());
}

static int irqsoff_flag_changed(struct trace_array *tr, u32 mask, int set)
@@ -577,7 +571,7 @@ static int irqsoff_flag_changed(struct trace_array *tr, u32 mask, int set)
struct tracer *tracer = tr->current_trace;

if (mask & TRACE_ITER_FUNCTION)
- irqsoff_function_set(set);
+ irqsoff_function_set(tr, set);

return trace_keep_overwrite(tracer, mask, set);
}
@@ -586,7 +580,7 @@ static int start_irqsoff_tracer(struct trace_array *tr, int graph)
{
int ret;

- ret = register_irqsoff_function(graph, 0);
+ ret = register_irqsoff_function(tr, graph, 0);

if (!ret && tracing_is_enabled())
tracer_enabled = 1;
@@ -600,7 +594,7 @@ static void stop_irqsoff_tracer(struct trace_array *tr, int graph)
{
tracer_enabled = 0;

- unregister_irqsoff_function(graph);
+ unregister_irqsoff_function(tr, graph);
}

static void __irqsoff_tracer_init(struct trace_array *tr)
@@ -617,7 +611,11 @@ static void __irqsoff_tracer_init(struct trace_array *tr)
smp_wmb();
tracing_reset_online_cpus(&tr->trace_buffer);

- if (start_irqsoff_tracer(tr, is_graph()))
+ ftrace_init_array_ops(tr, irqsoff_tracer_call);
+
+ /* Only toplevel instance supports graph tracing */
+ if (start_irqsoff_tracer(tr, (tr->flags & TRACE_ARRAY_FL_GLOBAL &&
+ is_graph())))
printk(KERN_ERR "failed to start irqsoff tracer\n");
}

@@ -630,6 +628,7 @@ static void irqsoff_tracer_reset(struct trace_array *tr)

set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag);
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag);
+ ftrace_reset_array_ops(tr);
}

static void irqsoff_tracer_start(struct trace_array *tr)
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index e14da5e..4dd986d 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -130,15 +130,9 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip,
atomic_dec(&data->disabled);
preempt_enable_notrace();
}
-
-static struct ftrace_ops trace_ops __read_mostly =
-{
- .func = wakeup_tracer_call,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
#endif /* CONFIG_FUNCTION_TRACER */

-static int register_wakeup_function(int graph, int set)
+static int register_wakeup_function(struct trace_array *tr, int graph, int set)
{
int ret;

@@ -150,7 +144,7 @@ static int register_wakeup_function(int graph, int set)
ret = register_ftrace_graph(&wakeup_graph_return,
&wakeup_graph_entry);
else
- ret = register_ftrace_function(&trace_ops);
+ ret = register_ftrace_function(tr->ops);

if (!ret)
function_enabled = true;
@@ -158,7 +152,7 @@ static int register_wakeup_function(int graph, int set)
return ret;
}

-static void unregister_wakeup_function(int graph)
+static void unregister_wakeup_function(struct trace_array *tr, int graph)
{
if (!function_enabled)
return;
@@ -166,17 +160,17 @@ static void unregister_wakeup_function(int graph)
if (graph)
unregister_ftrace_graph();
else
- unregister_ftrace_function(&trace_ops);
+ unregister_ftrace_function(tr->ops);

function_enabled = false;
}

-static void wakeup_function_set(int set)
+static void wakeup_function_set(struct trace_array *tr, int set)
{
if (set)
- register_wakeup_function(is_graph(), 1);
+ register_wakeup_function(tr, is_graph(), 1);
else
- unregister_wakeup_function(is_graph());
+ unregister_wakeup_function(tr, is_graph());
}

static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
@@ -184,16 +178,16 @@ static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
struct tracer *tracer = tr->current_trace;

if (mask & TRACE_ITER_FUNCTION)
- wakeup_function_set(set);
+ wakeup_function_set(tr, set);

return trace_keep_overwrite(tracer, mask, set);
}

-static int start_func_tracer(int graph)
+static int start_func_tracer(struct trace_array *tr, int graph)
{
int ret;

- ret = register_wakeup_function(graph, 0);
+ ret = register_wakeup_function(tr, graph, 0);

if (!ret && tracing_is_enabled())
tracer_enabled = 1;
@@ -203,11 +197,11 @@ static int start_func_tracer(int graph)
return ret;
}

-static void stop_func_tracer(int graph)
+static void stop_func_tracer(struct trace_array *tr, int graph)
{
tracer_enabled = 0;

- unregister_wakeup_function(graph);
+ unregister_wakeup_function(tr, graph);
}

#ifdef CONFIG_FUNCTION_GRAPH_TRACER
@@ -221,12 +215,12 @@ wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
if (!(is_graph() ^ set))
return 0;

- stop_func_tracer(!set);
+ stop_func_tracer(tr, !set);

wakeup_reset(wakeup_trace);
tracing_max_latency = 0;

- return start_func_tracer(set);
+ return start_func_tracer(tr, set);
}

static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
@@ -587,7 +581,7 @@ static void start_wakeup_tracer(struct trace_array *tr)
*/
smp_wmb();

- if (start_func_tracer(is_graph()))
+ if (start_func_tracer(tr, is_graph()))
printk(KERN_ERR "failed to start wakeup tracer\n");

return;
@@ -600,7 +594,7 @@ fail_deprobe:
static void stop_wakeup_tracer(struct trace_array *tr)
{
tracer_enabled = 0;
- stop_func_tracer(is_graph());
+ stop_func_tracer(tr, is_graph());
unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL);
unregister_trace_sched_wakeup_new(probe_wakeup, NULL);
unregister_trace_sched_wakeup(probe_wakeup, NULL);
@@ -617,6 +611,7 @@ static int __wakeup_tracer_init(struct trace_array *tr)

tracing_max_latency = 0;
wakeup_trace = tr;
+ ftrace_init_array_ops(tr, wakeup_tracer_call);
start_wakeup_tracer(tr);
return 0;
}
@@ -653,6 +648,7 @@ static void wakeup_tracer_reset(struct trace_array *tr)

set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag);
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag);
+ ftrace_reset_array_ops(tr);
}

static void wakeup_tracer_start(struct trace_array *tr)
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index e98fca6..519d04a 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -161,11 +161,6 @@ static struct ftrace_ops test_probe3 = {
.flags = FTRACE_OPS_FL_RECURSION_SAFE,
};

-static struct ftrace_ops test_global = {
- .func = trace_selftest_test_global_func,
- .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
-};
-
static void print_counts(void)
{
printk("(%d %d %d %d %d) ",
@@ -185,7 +180,7 @@ static void reset_counts(void)
trace_selftest_test_dyn_cnt = 0;
}

-static int trace_selftest_ops(int cnt)
+static int trace_selftest_ops(struct trace_array *tr, int cnt)
{
int save_ftrace_enabled = ftrace_enabled;
struct ftrace_ops *dyn_ops;
@@ -220,7 +215,11 @@ static int trace_selftest_ops(int cnt)
register_ftrace_function(&test_probe1);
register_ftrace_function(&test_probe2);
register_ftrace_function(&test_probe3);
- register_ftrace_function(&test_global);
+ /* First time we are running with main function */
+ if (cnt > 1) {
+ ftrace_init_array_ops(tr, trace_selftest_test_global_func);
+ register_ftrace_function(tr->ops);
+ }

DYN_FTRACE_TEST_NAME();

@@ -232,8 +231,10 @@ static int trace_selftest_ops(int cnt)
goto out;
if (trace_selftest_test_probe3_cnt != 1)
goto out;
- if (trace_selftest_test_global_cnt == 0)
- goto out;
+ if (cnt > 1) {
+ if (trace_selftest_test_global_cnt == 0)
+ goto out;
+ }

DYN_FTRACE_TEST_NAME2();

@@ -269,8 +270,10 @@ static int trace_selftest_ops(int cnt)
goto out_free;
if (trace_selftest_test_probe3_cnt != 3)
goto out_free;
- if (trace_selftest_test_global_cnt == 0)
- goto out;
+ if (cnt > 1) {
+ if (trace_selftest_test_global_cnt == 0)
+ goto out;
+ }
if (trace_selftest_test_dyn_cnt == 0)
goto out_free;

@@ -295,7 +298,9 @@ static int trace_selftest_ops(int cnt)
unregister_ftrace_function(&test_probe1);
unregister_ftrace_function(&test_probe2);
unregister_ftrace_function(&test_probe3);
- unregister_ftrace_function(&test_global);
+ if (cnt > 1)
+ unregister_ftrace_function(tr->ops);
+ ftrace_reset_array_ops(tr);

/* Make sure everything is off */
reset_counts();
@@ -388,7 +393,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
}

/* Test the ops with global tracing running */
- ret = trace_selftest_ops(1);
+ ret = trace_selftest_ops(tr, 1);
trace->reset(tr);

out:
@@ -399,7 +404,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,

/* Test the ops with global tracing off */
if (!ret)
- ret = trace_selftest_ops(2);
+ ret = trace_selftest_ops(tr, 2);

return ret;
}
--
1.8.5.3


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