* [for-next][PATCH 1/8] ftrace: Remove global function list and call function directly
2014-04-24 16:02 [for-next][PATCH 0/8] tracing: Mulitple tracers and other updates Steven Rostedt
@ 2014-04-24 16:02 ` Steven Rostedt
2014-04-24 16:02 ` [for-next][PATCH 2/8] tracing: Move tracing_max_latency into trace_array Steven Rostedt
` (6 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Steven Rostedt @ 2014-04-24 16:02 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Frederic Weisbecker, Andrew Morton
[-- Attachment #1: 0001-ftrace-Remove-global-function-list-and-call-function.patch --]
[-- Type: text/plain, Size: 26778 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
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@goodmis.org>
---
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
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [for-next][PATCH 2/8] tracing: Move tracing_max_latency into trace_array
2014-04-24 16:02 [for-next][PATCH 0/8] tracing: Mulitple tracers and other updates Steven Rostedt
2014-04-24 16:02 ` [for-next][PATCH 1/8] ftrace: Remove global function list and call function directly Steven Rostedt
@ 2014-04-24 16:02 ` Steven Rostedt
2014-04-24 16:02 ` [for-next][PATCH 3/8] tracing: Move ftrace_max_lock " Steven Rostedt
` (5 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Steven Rostedt @ 2014-04-24 16:02 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Frederic Weisbecker, Andrew Morton
[-- Attachment #1: 0002-tracing-Move-tracing_max_latency-into-trace_array.patch --]
[-- Type: text/plain, Size: 9886 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
In preparation for letting the latency tracers be used by instances,
remove the global tracing_max_latency variable and add a max_latency
field to the trace_array that the latency tracers will now use.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/trace.c | 14 ++++++--------
kernel/trace/trace.h | 3 +--
kernel/trace/trace_irqsoff.c | 14 +++++++-------
kernel/trace/trace_sched_wakeup.c | 12 ++++++------
kernel/trace/trace_selftest.c | 26 +++++++++++++-------------
5 files changed, 33 insertions(+), 36 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index fdd33aa..f5fc56b 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -982,8 +982,6 @@ static arch_spinlock_t ftrace_max_lock =
unsigned long __read_mostly tracing_thresh;
#ifdef CONFIG_TRACER_MAX_TRACE
-unsigned long __read_mostly tracing_max_latency;
-
/*
* Copy the new maximum trace into the separate maximum-trace
* structure. (this way the maximum trace is permanently saved,
@@ -1000,7 +998,7 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
max_buf->cpu = cpu;
max_buf->time_start = data->preempt_timestamp;
- max_data->saved_latency = tracing_max_latency;
+ max_data->saved_latency = tr->max_latency;
max_data->critical_start = data->critical_start;
max_data->critical_end = data->critical_end;
@@ -6328,6 +6326,11 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer)
trace_create_file("tracing_on", 0644, d_tracer,
tr, &rb_simple_fops);
+#ifdef CONFIG_TRACER_MAX_TRACE
+ trace_create_file("tracing_max_latency", 0644, d_tracer,
+ &tr->max_latency, &tracing_max_lat_fops);
+#endif
+
if (ftrace_create_function_files(tr, d_tracer))
WARN(1, "Could not allocate function filter files");
@@ -6353,11 +6356,6 @@ static __init int tracer_init_debugfs(void)
init_tracer_debugfs(&global_trace, d_tracer);
-#ifdef CONFIG_TRACER_MAX_TRACE
- trace_create_file("tracing_max_latency", 0644, d_tracer,
- &tracing_max_latency, &tracing_max_lat_fops);
-#endif
-
trace_create_file("tracing_thresh", 0644, d_tracer,
&tracing_thresh, &tracing_max_lat_fops);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index df5256b..644a8b5 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -190,6 +190,7 @@ struct trace_array {
*/
struct trace_buffer max_buffer;
bool allocated_snapshot;
+ unsigned long max_latency;
#endif
int buffer_disabled;
#ifdef CONFIG_FTRACE_SYSCALLS
@@ -599,8 +600,6 @@ extern unsigned long nsecs_to_usecs(unsigned long nsecs);
extern unsigned long tracing_thresh;
#ifdef CONFIG_TRACER_MAX_TRACE
-extern unsigned long tracing_max_latency;
-
void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
void update_max_tr_single(struct trace_array *tr,
struct task_struct *tsk, int cpu);
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index b5cb047..40aa300 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -170,7 +170,7 @@ irqsoff_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
for_each_possible_cpu(cpu)
per_cpu(tracing_cpu, cpu) = 0;
- tracing_max_latency = 0;
+ tr->max_latency = 0;
tracing_reset_online_cpus(&irqsoff_trace->trace_buffer);
return start_irqsoff_tracer(irqsoff_trace, set);
@@ -297,13 +297,13 @@ static void irqsoff_print_header(struct seq_file *s)
/*
* Should this new latency be reported/recorded?
*/
-static int report_latency(cycle_t delta)
+static int report_latency(struct trace_array *tr, cycle_t delta)
{
if (tracing_thresh) {
if (delta < tracing_thresh)
return 0;
} else {
- if (delta <= tracing_max_latency)
+ if (delta <= tr->max_latency)
return 0;
}
return 1;
@@ -327,13 +327,13 @@ check_critical_timing(struct trace_array *tr,
pc = preempt_count();
- if (!report_latency(delta))
+ if (!report_latency(tr, delta))
goto out;
raw_spin_lock_irqsave(&max_trace_lock, flags);
/* check if we are still the max latency */
- if (!report_latency(delta))
+ if (!report_latency(tr, delta))
goto out_unlock;
__trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
@@ -346,7 +346,7 @@ check_critical_timing(struct trace_array *tr,
data->critical_end = parent_ip;
if (likely(!is_tracing_stopped())) {
- tracing_max_latency = delta;
+ tr->max_latency = delta;
update_max_tr_single(tr, current, cpu);
}
@@ -605,7 +605,7 @@ static void __irqsoff_tracer_init(struct trace_array *tr)
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1);
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1);
- tracing_max_latency = 0;
+ tr->max_latency = 0;
irqsoff_trace = tr;
/* make sure that the tracer is visible */
smp_wmb();
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 4dd986d..41e0b8a 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -218,7 +218,7 @@ wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
stop_func_tracer(tr, !set);
wakeup_reset(wakeup_trace);
- tracing_max_latency = 0;
+ tr->max_latency = 0;
return start_func_tracer(tr, set);
}
@@ -344,13 +344,13 @@ static void wakeup_print_header(struct seq_file *s)
/*
* Should this new latency be reported/recorded?
*/
-static int report_latency(cycle_t delta)
+static int report_latency(struct trace_array *tr, cycle_t delta)
{
if (tracing_thresh) {
if (delta < tracing_thresh)
return 0;
} else {
- if (delta <= tracing_max_latency)
+ if (delta <= tr->max_latency)
return 0;
}
return 1;
@@ -418,11 +418,11 @@ probe_wakeup_sched_switch(void *ignore,
T1 = ftrace_now(cpu);
delta = T1-T0;
- if (!report_latency(delta))
+ if (!report_latency(wakeup_trace, delta))
goto out_unlock;
if (likely(!is_tracing_stopped())) {
- tracing_max_latency = delta;
+ wakeup_trace->max_latency = delta;
update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
}
@@ -609,7 +609,7 @@ static int __wakeup_tracer_init(struct trace_array *tr)
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1);
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1);
- tracing_max_latency = 0;
+ tr->max_latency = 0;
wakeup_trace = tr;
ftrace_init_array_ops(tr, wakeup_tracer_call);
start_wakeup_tracer(tr);
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 519d04a..ac31858 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -807,7 +807,7 @@ out:
int
trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
unsigned long count;
int ret;
@@ -819,7 +819,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
}
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
/* disable interrupts for a bit */
local_irq_disable();
udelay(100);
@@ -846,7 +846,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
ret = -1;
}
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
return ret;
}
@@ -856,7 +856,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
int
trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
unsigned long count;
int ret;
@@ -881,7 +881,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
}
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
/* disable preemption for a bit */
preempt_disable();
udelay(100);
@@ -908,7 +908,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
ret = -1;
}
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
return ret;
}
@@ -918,7 +918,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
int
trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *tr)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
unsigned long count;
int ret;
@@ -943,7 +943,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
}
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
/* disable preemption and interrupts for a bit */
preempt_disable();
@@ -978,7 +978,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
}
/* do the test by disabling interrupts first this time */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
tracing_start();
trace->start(tr);
@@ -1009,7 +1009,7 @@ out:
tracing_start();
out_no_start:
trace->reset(tr);
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
return ret;
}
@@ -1062,7 +1062,7 @@ static int trace_wakeup_test_thread(void *data)
int
trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
{
- unsigned long save_max = tracing_max_latency;
+ unsigned long save_max = tr->max_latency;
struct task_struct *p;
struct completion is_ready;
unsigned long count;
@@ -1088,7 +1088,7 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
}
/* reset the max latency */
- tracing_max_latency = 0;
+ tr->max_latency = 0;
while (p->on_rq) {
/*
@@ -1118,7 +1118,7 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
trace->reset(tr);
tracing_start();
- tracing_max_latency = save_max;
+ tr->max_latency = save_max;
/* kill the thread */
kthread_stop(p);
--
1.8.5.3
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [for-next][PATCH 3/8] tracing: Move ftrace_max_lock into trace_array
2014-04-24 16:02 [for-next][PATCH 0/8] tracing: Mulitple tracers and other updates Steven Rostedt
2014-04-24 16:02 ` [for-next][PATCH 1/8] ftrace: Remove global function list and call function directly Steven Rostedt
2014-04-24 16:02 ` [for-next][PATCH 2/8] tracing: Move tracing_max_latency into trace_array Steven Rostedt
@ 2014-04-24 16:02 ` Steven Rostedt
2014-04-24 16:02 ` [for-next][PATCH 4/8] tracing: Allow wakeup tracers to be used by instances Steven Rostedt
` (4 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Steven Rostedt @ 2014-04-24 16:02 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Frederic Weisbecker, Andrew Morton
[-- Attachment #1: 0003-tracing-Move-ftrace_max_lock-into-trace_array.patch --]
[-- Type: text/plain, Size: 6095 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
In preparation for having tracers enabled in instances, the max_lock
should be unique as updating the max for one tracer is a separate
operation than updating it for another tracer using a different max.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/trace.c | 40 ++++++++++++++--------------------------
kernel/trace/trace.h | 14 ++++++++++++++
kernel/trace/trace_selftest.c | 4 ++--
3 files changed, 30 insertions(+), 28 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index f5fc56b..bb5147a 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -963,22 +963,6 @@ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
return cnt;
}
-/*
- * ftrace_max_lock is used to protect the swapping of buffers
- * when taking a max snapshot. The buffers themselves are
- * protected by per_cpu spinlocks. But the action of the swap
- * needs its own lock.
- *
- * This is defined as a arch_spinlock_t in order to help
- * with performance when lockdep debugging is enabled.
- *
- * It is also used in other places outside the update_max_tr
- * so it needs to be defined outside of the
- * CONFIG_TRACER_MAX_TRACE.
- */
-static arch_spinlock_t ftrace_max_lock =
- (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
-
unsigned long __read_mostly tracing_thresh;
#ifdef CONFIG_TRACER_MAX_TRACE
@@ -1046,14 +1030,14 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
return;
}
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&tr->max_lock);
buf = tr->trace_buffer.buffer;
tr->trace_buffer.buffer = tr->max_buffer.buffer;
tr->max_buffer.buffer = buf;
__update_max_tr(tr, tsk, cpu);
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&tr->max_lock);
}
/**
@@ -1079,7 +1063,7 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
return;
}
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&tr->max_lock);
ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu);
@@ -1097,7 +1081,7 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY);
__update_max_tr(tr, tsk, cpu);
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&tr->max_lock);
}
#endif /* CONFIG_TRACER_MAX_TRACE */
@@ -1351,7 +1335,7 @@ void tracing_start(void)
}
/* Prevent the buffers from switching */
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&global_trace.max_lock);
buffer = global_trace.trace_buffer.buffer;
if (buffer)
@@ -1363,7 +1347,7 @@ void tracing_start(void)
ring_buffer_record_enable(buffer);
#endif
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&global_trace.max_lock);
ftrace_start();
out:
@@ -1418,7 +1402,7 @@ void tracing_stop(void)
goto out;
/* Prevent the buffers from switching */
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&global_trace.max_lock);
buffer = global_trace.trace_buffer.buffer;
if (buffer)
@@ -1430,7 +1414,7 @@ void tracing_stop(void)
ring_buffer_record_disable(buffer);
#endif
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&global_trace.max_lock);
out:
raw_spin_unlock_irqrestore(&global_trace.start_lock, flags);
@@ -3331,7 +3315,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
mutex_lock(&tracing_cpumask_update_lock);
local_irq_disable();
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&tr->max_lock);
for_each_tracing_cpu(cpu) {
/*
* Increase/decrease the disabled counter if we are
@@ -3348,7 +3332,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu);
}
}
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&tr->max_lock);
local_irq_enable();
cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new);
@@ -6129,6 +6113,8 @@ static int new_instance_create(const char *name)
raw_spin_lock_init(&tr->start_lock);
+ tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
+
tr->current_trace = &nop_trace;
INIT_LIST_HEAD(&tr->systems);
@@ -6627,6 +6613,8 @@ __init static int tracer_alloc_buffers(void)
*/
global_trace.current_trace = &nop_trace;
+ global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
+
ftrace_init_global_array_ops(&global_trace);
register_tracer(&nop_trace);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 644a8b5..5d2f07d 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -192,6 +192,20 @@ struct trace_array {
bool allocated_snapshot;
unsigned long max_latency;
#endif
+ /*
+ * max_lock is used to protect the swapping of buffers
+ * when taking a max snapshot. The buffers themselves are
+ * protected by per_cpu spinlocks. But the action of the swap
+ * needs its own lock.
+ *
+ * This is defined as a arch_spinlock_t in order to help
+ * with performance when lockdep debugging is enabled.
+ *
+ * It is also used in other places outside the update_max_tr
+ * so it needs to be defined outside of the
+ * CONFIG_TRACER_MAX_TRACE.
+ */
+ arch_spinlock_t max_lock;
int buffer_disabled;
#ifdef CONFIG_FTRACE_SYSCALLS
int sys_refcount_enter;
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index ac31858..1c95cd7 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -65,7 +65,7 @@ static int trace_test_buffer(struct trace_buffer *buf, unsigned long *count)
/* Don't allow flipping of max traces now */
local_irq_save(flags);
- arch_spin_lock(&ftrace_max_lock);
+ arch_spin_lock(&buf->tr->max_lock);
cnt = ring_buffer_entries(buf->buffer);
@@ -83,7 +83,7 @@ static int trace_test_buffer(struct trace_buffer *buf, unsigned long *count)
break;
}
tracing_on();
- arch_spin_unlock(&ftrace_max_lock);
+ arch_spin_unlock(&buf->tr->max_lock);
local_irq_restore(flags);
if (count)
--
1.8.5.3
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [for-next][PATCH 4/8] tracing: Allow wakeup tracers to be used by instances
2014-04-24 16:02 [for-next][PATCH 0/8] tracing: Mulitple tracers and other updates Steven Rostedt
` (2 preceding siblings ...)
2014-04-24 16:02 ` [for-next][PATCH 3/8] tracing: Move ftrace_max_lock " Steven Rostedt
@ 2014-04-24 16:02 ` Steven Rostedt
2014-04-24 16:02 ` [for-next][PATCH 5/8] tracing: Allow irq/preempt " Steven Rostedt
` (3 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Steven Rostedt @ 2014-04-24 16:02 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Frederic Weisbecker, Andrew Morton
[-- Attachment #1: 0004-tracing-Allow-wakeup-tracers-to-be-used-by-instances.patch --]
[-- Type: text/plain, Size: 2498 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
The wakeup and wakeup_rt tracers can now be used by instances.
But they may only be used by one instance at a time (including the
top level directory). This allows multiple tracers to run while
the wakeup tracer is running simultaneously.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/trace_sched_wakeup.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 41e0b8a..1573c03 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -601,6 +601,8 @@ static void stop_wakeup_tracer(struct trace_array *tr)
unregister_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL);
}
+static bool wakeup_busy;
+
static int __wakeup_tracer_init(struct trace_array *tr)
{
save_flags = trace_flags;
@@ -613,11 +615,16 @@ static int __wakeup_tracer_init(struct trace_array *tr)
wakeup_trace = tr;
ftrace_init_array_ops(tr, wakeup_tracer_call);
start_wakeup_tracer(tr);
+
+ wakeup_busy = true;
return 0;
}
static int wakeup_tracer_init(struct trace_array *tr)
{
+ if (wakeup_busy)
+ return -EBUSY;
+
wakeup_dl = 0;
wakeup_rt = 0;
return __wakeup_tracer_init(tr);
@@ -625,6 +632,9 @@ static int wakeup_tracer_init(struct trace_array *tr)
static int wakeup_rt_tracer_init(struct trace_array *tr)
{
+ if (wakeup_busy)
+ return -EBUSY;
+
wakeup_dl = 0;
wakeup_rt = 1;
return __wakeup_tracer_init(tr);
@@ -632,6 +642,9 @@ static int wakeup_rt_tracer_init(struct trace_array *tr)
static int wakeup_dl_tracer_init(struct trace_array *tr)
{
+ if (wakeup_busy)
+ return -EBUSY;
+
wakeup_dl = 1;
wakeup_rt = 0;
return __wakeup_tracer_init(tr);
@@ -649,6 +662,7 @@ 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);
+ wakeup_busy = false;
}
static void wakeup_tracer_start(struct trace_array *tr)
@@ -680,6 +694,7 @@ static struct tracer wakeup_tracer __read_mostly =
#endif
.open = wakeup_trace_open,
.close = wakeup_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
@@ -702,6 +717,7 @@ static struct tracer wakeup_rt_tracer __read_mostly =
#endif
.open = wakeup_trace_open,
.close = wakeup_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
--
1.8.5.3
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [for-next][PATCH 5/8] tracing: Allow irq/preempt tracers to be used by instances
2014-04-24 16:02 [for-next][PATCH 0/8] tracing: Mulitple tracers and other updates Steven Rostedt
` (3 preceding siblings ...)
2014-04-24 16:02 ` [for-next][PATCH 4/8] tracing: Allow wakeup tracers to be used by instances Steven Rostedt
@ 2014-04-24 16:02 ` Steven Rostedt
2014-04-24 16:02 ` [for-next][PATCH 6/8] ftrace/x86: Fix order of warning messages when ftrace modifies code Steven Rostedt
` (2 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: Steven Rostedt @ 2014-04-24 16:02 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Frederic Weisbecker, Andrew Morton
[-- Attachment #1: 0005-tracing-Allow-irq-preempt-tracers-to-be-used-by-inst.patch --]
[-- Type: text/plain, Size: 3256 bytes --]
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
The irqsoff, preemptoff and preemptirqsoff tracers can now be used by
instances. But they may only be used by one instance at a time (including
the top level directory). This allows multiple tracers to run while the
irqsoff (and friends) tracer is running simultaneously.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/trace_irqsoff.c | 24 +++++++++++++++++-------
1 file changed, 17 insertions(+), 7 deletions(-)
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 40aa300..9bb104f 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -597,8 +597,13 @@ static void stop_irqsoff_tracer(struct trace_array *tr, int graph)
unregister_irqsoff_function(tr, graph);
}
-static void __irqsoff_tracer_init(struct trace_array *tr)
+static bool irqsoff_busy;
+
+static int __irqsoff_tracer_init(struct trace_array *tr)
{
+ if (irqsoff_busy)
+ return -EBUSY;
+
save_flags = trace_flags;
/* non overwrite screws up the latency tracers */
@@ -617,6 +622,9 @@ static void __irqsoff_tracer_init(struct trace_array *tr)
if (start_irqsoff_tracer(tr, (tr->flags & TRACE_ARRAY_FL_GLOBAL &&
is_graph())))
printk(KERN_ERR "failed to start irqsoff tracer\n");
+
+ irqsoff_busy = true;
+ return 0;
}
static void irqsoff_tracer_reset(struct trace_array *tr)
@@ -629,6 +637,8 @@ 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);
+
+ irqsoff_busy = false;
}
static void irqsoff_tracer_start(struct trace_array *tr)
@@ -646,8 +656,7 @@ static int irqsoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_IRQS_OFF;
- __irqsoff_tracer_init(tr);
- return 0;
+ return __irqsoff_tracer_init(tr);
}
static struct tracer irqsoff_tracer __read_mostly =
{
@@ -667,6 +676,7 @@ static struct tracer irqsoff_tracer __read_mostly =
#endif
.open = irqsoff_trace_open,
.close = irqsoff_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
# define register_irqsoff(trace) register_tracer(&trace)
@@ -679,8 +689,7 @@ static int preemptoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_PREEMPT_OFF;
- __irqsoff_tracer_init(tr);
- return 0;
+ return __irqsoff_tracer_init(tr);
}
static struct tracer preemptoff_tracer __read_mostly =
@@ -701,6 +710,7 @@ static struct tracer preemptoff_tracer __read_mostly =
#endif
.open = irqsoff_trace_open,
.close = irqsoff_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
# define register_preemptoff(trace) register_tracer(&trace)
@@ -715,8 +725,7 @@ static int preemptirqsoff_tracer_init(struct trace_array *tr)
{
trace_type = TRACER_IRQS_OFF | TRACER_PREEMPT_OFF;
- __irqsoff_tracer_init(tr);
- return 0;
+ return __irqsoff_tracer_init(tr);
}
static struct tracer preemptirqsoff_tracer __read_mostly =
@@ -737,6 +746,7 @@ static struct tracer preemptirqsoff_tracer __read_mostly =
#endif
.open = irqsoff_trace_open,
.close = irqsoff_trace_close,
+ .allow_instances = true,
.use_max_tr = true,
};
--
1.8.5.3
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [for-next][PATCH 6/8] ftrace/x86: Fix order of warning messages when ftrace modifies code
2014-04-24 16:02 [for-next][PATCH 0/8] tracing: Mulitple tracers and other updates Steven Rostedt
` (4 preceding siblings ...)
2014-04-24 16:02 ` [for-next][PATCH 5/8] tracing: Allow irq/preempt " Steven Rostedt
@ 2014-04-24 16:02 ` Steven Rostedt
2014-04-24 16:02 ` [for-next][PATCH 7/8] ftrace: Statically initialize pm notifier block Steven Rostedt
2014-04-24 16:02 ` [for-next][PATCH 8/8] tracing: Add static to local functions Steven Rostedt
7 siblings, 0 replies; 9+ messages in thread
From: Steven Rostedt @ 2014-04-24 16:02 UTC (permalink / raw)
To: linux-kernel; +Cc: Ingo Molnar, Frederic Weisbecker, Andrew Morton, Petr Mladek
[-- Attachment #1: 0006-ftrace-x86-Fix-order-of-warning-messages-when-ftrace.patch --]
[-- Type: text/plain, Size: 1007 bytes --]
From: Petr Mladek <pmladek@suse.cz>
The colon at the end of the printk message suggests that it should get printed
before the details printed by ftrace_bug().
When touching the line, let's use the preferred pr_warn() macro as suggested
by checkpatch.pl.
Link: http://lkml.kernel.org/r/1392650573-3390-5-git-send-email-pmladek@suse.cz
Signed-off-by: Petr Mladek <pmladek@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
arch/x86/kernel/ftrace.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 52819e8..3d837b0 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -621,8 +621,8 @@ void ftrace_replace_code(int enable)
return;
remove_breakpoints:
+ pr_warn("Failed on %s (%d):\n", report, count);
ftrace_bug(ret, rec ? rec->ip : 0);
- printk(KERN_WARNING "Failed on %s (%d):\n", report, count);
for_ftrace_rec_iter(iter) {
rec = ftrace_rec_iter_record(iter);
/*
--
1.8.5.3
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [for-next][PATCH 7/8] ftrace: Statically initialize pm notifier block
2014-04-24 16:02 [for-next][PATCH 0/8] tracing: Mulitple tracers and other updates Steven Rostedt
` (5 preceding siblings ...)
2014-04-24 16:02 ` [for-next][PATCH 6/8] ftrace/x86: Fix order of warning messages when ftrace modifies code Steven Rostedt
@ 2014-04-24 16:02 ` Steven Rostedt
2014-04-24 16:02 ` [for-next][PATCH 8/8] tracing: Add static to local functions Steven Rostedt
7 siblings, 0 replies; 9+ messages in thread
From: Steven Rostedt @ 2014-04-24 16:02 UTC (permalink / raw)
To: linux-kernel
Cc: Ingo Molnar, Frederic Weisbecker, Andrew Morton, Ingo Molnar,
PaX Team, Mathias Krause
[-- Attachment #1: 0007-ftrace-Statically-initialize-pm-notifier-block.patch --]
[-- Type: text/plain, Size: 1636 bytes --]
From: Mathias Krause <minipli@googlemail.com>
Instead of initializing the pm notifier block in register_ftrace_graph(),
initialize it statically. This safes us some code.
Found in the PaX patch, written by the PaX Team.
Link: http://lkml.kernel.org/p/1396186310-3156-1-git-send-email-minipli@googlemail.com
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: PaX Team <pageexec@freemail.hu>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/ftrace.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8f61ef7..846888e 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -4860,7 +4860,6 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
static int ftrace_graph_active;
-static struct notifier_block ftrace_suspend_notifier;
int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace)
{
@@ -5036,6 +5035,10 @@ static void update_function_graph_func(void)
ftrace_graph_entry = ftrace_graph_entry_test;
}
+static struct notifier_block ftrace_suspend_notifier = {
+ .notifier_call = ftrace_suspend_notifier_call,
+};
+
int register_ftrace_graph(trace_func_graph_ret_t retfunc,
trace_func_graph_ent_t entryfunc)
{
@@ -5049,7 +5052,6 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
goto out;
}
- ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call;
register_pm_notifier(&ftrace_suspend_notifier);
ftrace_graph_active++;
--
1.8.5.3
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [for-next][PATCH 8/8] tracing: Add static to local functions
2014-04-24 16:02 [for-next][PATCH 0/8] tracing: Mulitple tracers and other updates Steven Rostedt
` (6 preceding siblings ...)
2014-04-24 16:02 ` [for-next][PATCH 7/8] ftrace: Statically initialize pm notifier block Steven Rostedt
@ 2014-04-24 16:02 ` Steven Rostedt
7 siblings, 0 replies; 9+ messages in thread
From: Steven Rostedt @ 2014-04-24 16:02 UTC (permalink / raw)
To: linux-kernel
Cc: Ingo Molnar, Frederic Weisbecker, Andrew Morton, Fabian Frederick
[-- Attachment #1: 0008-tracing-Add-static-to-local-functions.patch --]
[-- Type: text/plain, Size: 1856 bytes --]
From: Fabian Frederick <fabf@skynet.be>
This patch adds static to the following functions:
-cycle_t buffer_ftrace_now
-void free_snapshot
-int trace_selftest_startup_dynamic_tracing
Link: http://lkml.kernel.org/p/20140417214442.d7abc7c0b0e4b90e7fedecc9@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/trace/trace.c | 4 ++--
kernel/trace/trace_selftest.c | 6 +++---
2 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index bb5147a..cb41e98 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -275,7 +275,7 @@ int call_filter_check_discard(struct ftrace_event_call *call, void *rec,
}
EXPORT_SYMBOL_GPL(call_filter_check_discard);
-cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu)
+static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu)
{
u64 ts;
@@ -599,7 +599,7 @@ static int alloc_snapshot(struct trace_array *tr)
return 0;
}
-void free_snapshot(struct trace_array *tr)
+static void free_snapshot(struct trace_array *tr)
{
/*
* We don't free the ring buffer. instead, resize it because
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 1c95cd7..5ef6049 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -320,9 +320,9 @@ static int trace_selftest_ops(struct trace_array *tr, int cnt)
}
/* Test dynamic code modification and ftrace filters */
-int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
- struct trace_array *tr,
- int (*func)(void))
+static int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
+ struct trace_array *tr,
+ int (*func)(void))
{
int save_ftrace_enabled = ftrace_enabled;
unsigned long count;
--
1.8.5.3
^ permalink raw reply related [flat|nested] 9+ messages in thread