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-rw-r--r--kernel/trace/Kconfig19
-rw-r--r--kernel/trace/Makefile2
-rw-r--r--kernel/trace/ftrace.c306
-rw-r--r--kernel/trace/trace.c79
-rw-r--r--kernel/trace/trace.h35
-rw-r--r--kernel/trace/trace_functions_graph.c175
-rw-r--r--kernel/trace/trace_functions_return.c98
7 files changed, 491 insertions, 223 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index d151aab48ed..8b6b673b4d6 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -12,7 +12,7 @@ config NOP_TRACER
config HAVE_FUNCTION_TRACER
bool
-config HAVE_FUNCTION_RET_TRACER
+config HAVE_FUNCTION_GRAPH_TRACER
bool
config HAVE_FUNCTION_TRACE_MCOUNT_TEST
@@ -63,15 +63,18 @@ config FUNCTION_TRACER
(the bootup default), then the overhead of the instructions is very
small and not measurable even in micro-benchmarks.
-config FUNCTION_RET_TRACER
- bool "Kernel Function return Tracer"
- depends on HAVE_FUNCTION_RET_TRACER
+config FUNCTION_GRAPH_TRACER
+ bool "Kernel Function Graph Tracer"
+ depends on HAVE_FUNCTION_GRAPH_TRACER
depends on FUNCTION_TRACER
help
- Enable the kernel to trace a function at its return.
- It's first purpose is to trace the duration of functions.
- This is done by setting the current return address on the thread
- info structure of the current task.
+ Enable the kernel to trace a function at both its return
+ and its entry.
+ It's first purpose is to trace the duration of functions and
+ draw a call graph for each thread with some informations like
+ the return value.
+ This is done by setting the current return address on the current
+ task structure into a stack of calls.
config IRQSOFF_TRACER
bool "Interrupts-off Latency Tracer"
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index acaa06553ec..62dc561b667 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -29,7 +29,7 @@ obj-$(CONFIG_NOP_TRACER) += trace_nop.o
obj-$(CONFIG_STACK_TRACER) += trace_stack.o
obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o
obj-$(CONFIG_BOOT_TRACER) += trace_boot.o
-obj-$(CONFIG_FUNCTION_RET_TRACER) += trace_functions_return.o
+obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o
obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o
obj-$(CONFIG_BTS_TRACER) += trace_bts.o
obj-$(CONFIG_POWER_TRACER) += trace_power.o
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 53042f118f2..cbf8b09f63a 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -47,12 +47,12 @@
int ftrace_enabled __read_mostly;
static int last_ftrace_enabled;
+/* ftrace_pid_trace >= 0 will only trace threads with this pid */
+static int ftrace_pid_trace = -1;
+
/* Quick disabling of function tracer. */
int function_trace_stop;
-/* By default, current tracing type is normal tracing. */
-enum ftrace_tracing_type_t ftrace_tracing_type = FTRACE_TYPE_ENTER;
-
/*
* ftrace_disabled is set when an anomaly is discovered.
* ftrace_disabled is much stronger than ftrace_enabled.
@@ -61,6 +61,7 @@ static int ftrace_disabled __read_mostly;
static DEFINE_SPINLOCK(ftrace_lock);
static DEFINE_MUTEX(ftrace_sysctl_lock);
+static DEFINE_MUTEX(ftrace_start_lock);
static struct ftrace_ops ftrace_list_end __read_mostly =
{
@@ -70,6 +71,7 @@ static struct ftrace_ops ftrace_list_end __read_mostly =
static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end;
ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub;
+ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub;
static void ftrace_list_func(unsigned long ip, unsigned long parent_ip)
{
@@ -86,6 +88,21 @@ static void ftrace_list_func(unsigned long ip, unsigned long parent_ip)
};
}
+static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip)
+{
+ if (current->pid != ftrace_pid_trace)
+ return;
+
+ ftrace_pid_function(ip, parent_ip);
+}
+
+static void set_ftrace_pid_function(ftrace_func_t func)
+{
+ /* do not set ftrace_pid_function to itself! */
+ if (func != ftrace_pid_func)
+ ftrace_pid_function = func;
+}
+
/**
* clear_ftrace_function - reset the ftrace function
*
@@ -96,6 +113,7 @@ void clear_ftrace_function(void)
{
ftrace_trace_function = ftrace_stub;
__ftrace_trace_function = ftrace_stub;
+ ftrace_pid_function = ftrace_stub;
}
#ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
@@ -128,20 +146,26 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
ftrace_list = ops;
if (ftrace_enabled) {
+ ftrace_func_t func;
+
+ if (ops->next == &ftrace_list_end)
+ func = ops->func;
+ else
+ func = ftrace_list_func;
+
+ if (ftrace_pid_trace >= 0) {
+ set_ftrace_pid_function(func);
+ func = ftrace_pid_func;
+ }
+
/*
* For one func, simply call it directly.
* For more than one func, call the chain.
*/
#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
- if (ops->next == &ftrace_list_end)
- ftrace_trace_function = ops->func;
- else
- ftrace_trace_function = ftrace_list_func;
+ ftrace_trace_function = func;
#else
- if (ops->next == &ftrace_list_end)
- __ftrace_trace_function = ops->func;
- else
- __ftrace_trace_function = ftrace_list_func;
+ __ftrace_trace_function = func;
ftrace_trace_function = ftrace_test_stop_func;
#endif
}
@@ -182,8 +206,19 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
if (ftrace_enabled) {
/* If we only have one func left, then call that directly */
- if (ftrace_list->next == &ftrace_list_end)
- ftrace_trace_function = ftrace_list->func;
+ if (ftrace_list->next == &ftrace_list_end) {
+ ftrace_func_t func = ftrace_list->func;
+
+ if (ftrace_pid_trace >= 0) {
+ set_ftrace_pid_function(func);
+ func = ftrace_pid_func;
+ }
+#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
+ ftrace_trace_function = func;
+#else
+ __ftrace_trace_function = func;
+#endif
+ }
}
out:
@@ -192,6 +227,38 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops)
return ret;
}
+static void ftrace_update_pid_func(void)
+{
+ ftrace_func_t func;
+
+ /* should not be called from interrupt context */
+ spin_lock(&ftrace_lock);
+
+ if (ftrace_trace_function == ftrace_stub)
+ goto out;
+
+ func = ftrace_trace_function;
+
+ if (ftrace_pid_trace >= 0) {
+ set_ftrace_pid_function(func);
+ func = ftrace_pid_func;
+ } else {
+ if (func != ftrace_pid_func)
+ goto out;
+
+ set_ftrace_pid_function(func);
+ }
+
+#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
+ ftrace_trace_function = func;
+#else
+ __ftrace_trace_function = func;
+#endif
+
+ out:
+ spin_unlock(&ftrace_lock);
+}
+
#ifdef CONFIG_DYNAMIC_FTRACE
#ifndef CONFIG_FTRACE_MCOUNT_RECORD
# error Dynamic ftrace depends on MCOUNT_RECORD
@@ -211,6 +278,8 @@ enum {
FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
FTRACE_ENABLE_MCOUNT = (1 << 3),
FTRACE_DISABLE_MCOUNT = (1 << 4),
+ FTRACE_START_FUNC_RET = (1 << 5),
+ FTRACE_STOP_FUNC_RET = (1 << 6),
};
static int ftrace_filtered;
@@ -395,14 +464,7 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
unsigned long ip, fl;
unsigned long ftrace_addr;
-#ifdef CONFIG_FUNCTION_RET_TRACER
- if (ftrace_tracing_type == FTRACE_TYPE_ENTER)
- ftrace_addr = (unsigned long)ftrace_caller;
- else
- ftrace_addr = (unsigned long)ftrace_return_caller;
-#else
ftrace_addr = (unsigned long)ftrace_caller;
-#endif
ip = rec->ip;
@@ -535,6 +597,11 @@ static int __ftrace_modify_code(void *data)
if (*command & FTRACE_UPDATE_TRACE_FUNC)
ftrace_update_ftrace_func(ftrace_trace_function);
+ if (*command & FTRACE_START_FUNC_RET)
+ ftrace_enable_ftrace_graph_caller();
+ else if (*command & FTRACE_STOP_FUNC_RET)
+ ftrace_disable_ftrace_graph_caller();
+
return 0;
}
@@ -545,12 +612,22 @@ static void ftrace_run_update_code(int command)
static ftrace_func_t saved_ftrace_func;
static int ftrace_start_up;
-static DEFINE_MUTEX(ftrace_start_lock);
-static void ftrace_startup(void)
+static void ftrace_startup_enable(int command)
{
- int command = 0;
+ if (saved_ftrace_func != ftrace_trace_function) {
+ saved_ftrace_func = ftrace_trace_function;
+ command |= FTRACE_UPDATE_TRACE_FUNC;
+ }
+
+ if (!command || !ftrace_enabled)
+ return;
+
+ ftrace_run_update_code(command);
+}
+static void ftrace_startup(int command)
+{
if (unlikely(ftrace_disabled))
return;
@@ -558,23 +635,13 @@ static void ftrace_startup(void)
ftrace_start_up++;
command |= FTRACE_ENABLE_CALLS;
- if (saved_ftrace_func != ftrace_trace_function) {
- saved_ftrace_func = ftrace_trace_function;
- command |= FTRACE_UPDATE_TRACE_FUNC;
- }
+ ftrace_startup_enable(command);
- if (!command || !ftrace_enabled)
- goto out;
-
- ftrace_run_update_code(command);
- out:
mutex_unlock(&ftrace_start_lock);
}
-static void ftrace_shutdown(void)
+static void ftrace_shutdown(int command)
{
- int command = 0;
-
if (unlikely(ftrace_disabled))
return;
@@ -1262,13 +1329,10 @@ static struct file_operations ftrace_notrace_fops = {
.release = ftrace_notrace_release,
};
-static __init int ftrace_init_debugfs(void)
+static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer)
{
- struct dentry *d_tracer;
struct dentry *entry;
- d_tracer = tracing_init_dentry();
-
entry = debugfs_create_file("available_filter_functions", 0444,
d_tracer, NULL, &ftrace_avail_fops);
if (!entry)
@@ -1295,8 +1359,6 @@ static __init int ftrace_init_debugfs(void)
return 0;
}
-fs_initcall(ftrace_init_debugfs);
-
static int ftrace_convert_nops(struct module *mod,
unsigned long *start,
unsigned long *end)
@@ -1382,12 +1444,101 @@ static int __init ftrace_nodyn_init(void)
}
device_initcall(ftrace_nodyn_init);
-# define ftrace_startup() do { } while (0)
-# define ftrace_shutdown() do { } while (0)
+static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; }
+static inline void ftrace_startup_enable(int command) { }
+/* Keep as macros so we do not need to define the commands */
+# define ftrace_startup(command) do { } while (0)
+# define ftrace_shutdown(command) do { } while (0)
# define ftrace_startup_sysctl() do { } while (0)
# define ftrace_shutdown_sysctl() do { } while (0)
#endif /* CONFIG_DYNAMIC_FTRACE */
+static ssize_t
+ftrace_pid_read(struct file *file, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64];
+ int r;
+
+ if (ftrace_pid_trace >= 0)
+ r = sprintf(buf, "%u\n", ftrace_pid_trace);
+ else
+ r = sprintf(buf, "no pid\n");
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+ftrace_pid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64];
+ long val;
+ int ret;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ ret = strict_strtol(buf, 10, &val);
+ if (ret < 0)
+ return ret;
+
+ mutex_lock(&ftrace_start_lock);
+ if (ret < 0) {
+ /* disable pid tracing */
+ if (ftrace_pid_trace < 0)
+ goto out;
+ ftrace_pid_trace = -1;
+
+ } else {
+
+ if (ftrace_pid_trace == val)
+ goto out;
+
+ ftrace_pid_trace = val;
+ }
+
+ /* update the function call */
+ ftrace_update_pid_func();
+ ftrace_startup_enable(0);
+
+ out:
+ mutex_unlock(&ftrace_start_lock);
+
+ return cnt;
+}
+
+static struct file_operations ftrace_pid_fops = {
+ .read = ftrace_pid_read,
+ .write = ftrace_pid_write,
+};
+
+static __init int ftrace_init_debugfs(void)
+{
+ struct dentry *d_tracer;
+ struct dentry *entry;
+
+ d_tracer = tracing_init_dentry();
+ if (!d_tracer)
+ return 0;
+
+ ftrace_init_dyn_debugfs(d_tracer);
+
+ entry = debugfs_create_file("set_ftrace_pid", 0644, d_tracer,
+ NULL, &ftrace_pid_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'set_ftrace_pid' entry\n");
+ return 0;
+}
+
+fs_initcall(ftrace_init_debugfs);
+
/**
* ftrace_kill - kill ftrace
*
@@ -1422,15 +1573,9 @@ int register_ftrace_function(struct ftrace_ops *ops)
mutex_lock(&ftrace_sysctl_lock);
- if (ftrace_tracing_type == FTRACE_TYPE_RETURN) {
- ret = -EBUSY;
- goto out;
- }
-
ret = __register_ftrace_function(ops);
- ftrace_startup();
+ ftrace_startup(0);
-out:
mutex_unlock(&ftrace_sysctl_lock);
return ret;
}
@@ -1447,7 +1592,7 @@ int unregister_ftrace_function(struct ftrace_ops *ops)
mutex_lock(&ftrace_sysctl_lock);
ret = __unregister_ftrace_function(ops);
- ftrace_shutdown();
+ ftrace_shutdown(0);
mutex_unlock(&ftrace_sysctl_lock);
return ret;
@@ -1496,14 +1641,15 @@ ftrace_enable_sysctl(struct ctl_table *table, int write,
return ret;
}
-#ifdef CONFIG_FUNCTION_RET_TRACER
-
-static atomic_t ftrace_retfunc_active;
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-/* The callback that hooks the return of a function */
-trace_function_return_t ftrace_function_return =
- (trace_function_return_t)ftrace_stub;
+static atomic_t ftrace_graph_active;
+/* The callbacks that hook a function */
+trace_func_graph_ret_t ftrace_graph_return =
+ (trace_func_graph_ret_t)ftrace_stub;
+trace_func_graph_ent_t ftrace_graph_entry =
+ (trace_func_graph_ent_t)ftrace_stub;
/* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */
static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list)
@@ -1549,7 +1695,7 @@ free:
}
/* Allocate a return stack for each task */
-static int start_return_tracing(void)
+static int start_graph_tracing(void)
{
struct ftrace_ret_stack **ret_stack_list;
int ret;
@@ -1569,52 +1715,46 @@ static int start_return_tracing(void)
return ret;
}
-int register_ftrace_return(trace_function_return_t func)
+int register_ftrace_graph(trace_func_graph_ret_t retfunc,
+ trace_func_graph_ent_t entryfunc)
{
int ret = 0;
mutex_lock(&ftrace_sysctl_lock);
- /*
- * Don't launch return tracing if normal function
- * tracing is already running.
- */
- if (ftrace_trace_function != ftrace_stub) {
- ret = -EBUSY;
- goto out;
- }
- atomic_inc(&ftrace_retfunc_active);
- ret = start_return_tracing();
+ atomic_inc(&ftrace_graph_active);
+ ret = start_graph_tracing();
if (ret) {
- atomic_dec(&ftrace_retfunc_active);
+ atomic_dec(&ftrace_graph_active);
goto out;
}
- ftrace_tracing_type = FTRACE_TYPE_RETURN;
- ftrace_function_return = func;
- ftrace_startup();
+
+ ftrace_graph_return = retfunc;
+ ftrace_graph_entry = entryfunc;
+
+ ftrace_startup(FTRACE_START_FUNC_RET);
out:
mutex_unlock(&ftrace_sysctl_lock);
return ret;
}
-void unregister_ftrace_return(void)
+void unregister_ftrace_graph(void)
{
mutex_lock(&ftrace_sysctl_lock);
- atomic_dec(&ftrace_retfunc_active);
- ftrace_function_return = (trace_function_return_t)ftrace_stub;
- ftrace_shutdown();
- /* Restore normal tracing type */
- ftrace_tracing_type = FTRACE_TYPE_ENTER;
+ atomic_dec(&ftrace_graph_active);
+ ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
+ ftrace_graph_entry = (trace_func_graph_ent_t)ftrace_stub;
+ ftrace_shutdown(FTRACE_STOP_FUNC_RET);
mutex_unlock(&ftrace_sysctl_lock);
}
/* Allocate a return stack for newly created task */
-void ftrace_retfunc_init_task(struct task_struct *t)
+void ftrace_graph_init_task(struct task_struct *t)
{
- if (atomic_read(&ftrace_retfunc_active)) {
+ if (atomic_read(&ftrace_graph_active)) {
t->ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH
* sizeof(struct ftrace_ret_stack),
GFP_KERNEL);
@@ -1626,7 +1766,7 @@ void ftrace_retfunc_init_task(struct task_struct *t)
t->ret_stack = NULL;
}
-void ftrace_retfunc_exit_task(struct task_struct *t)
+void ftrace_graph_exit_task(struct task_struct *t)
{
struct ftrace_ret_stack *ret_stack = t->ret_stack;
@@ -1638,5 +1778,3 @@ void ftrace_retfunc_exit_task(struct task_struct *t)
}
#endif
-
-
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 8df8fdd69c9..5811e0a5f73 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -804,7 +804,7 @@ static void trace_save_cmdline(struct task_struct *tsk)
spin_unlock(&trace_cmdline_lock);
}
-static char *trace_find_cmdline(int pid)
+char *trace_find_cmdline(int pid)
{
char *cmdline = "<...>";
unsigned map;
@@ -878,15 +878,15 @@ trace_function(struct trace_array *tr, struct trace_array_cpu *data,
ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
}
-#ifdef CONFIG_FUNCTION_RET_TRACER
-static void __trace_function_return(struct trace_array *tr,
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+static void __trace_graph_entry(struct trace_array *tr,
struct trace_array_cpu *data,
- struct ftrace_retfunc *trace,
+ struct ftrace_graph_ent *trace,
unsigned long flags,
int pc)
{
struct ring_buffer_event *event;
- struct ftrace_ret_entry *entry;
+ struct ftrace_graph_ent_entry *entry;
unsigned long irq_flags;
if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
@@ -898,12 +898,32 @@ static void __trace_function_return(struct trace_array *tr,
return;
entry = ring_buffer_event_data(event);
tracing_generic_entry_update(&entry->ent, flags, pc);
- entry->ent.type = TRACE_FN_RET;
- entry->ip = trace->func;
- entry->parent_ip = trace->ret;
- entry->rettime = trace->rettime;
- entry->calltime = trace->calltime;
- entry->overrun = trace->overrun;
+ entry->ent.type = TRACE_GRAPH_ENT;
+ entry->graph_ent = *trace;
+ ring_buffer_unlock_commit(global_trace.buffer, event, irq_flags);
+}
+
+static void __trace_graph_return(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ struct ftrace_graph_ret *trace,
+ unsigned long flags,
+ int pc)
+{
+ struct ring_buffer_event *event;
+ struct ftrace_graph_ret_entry *entry;
+ unsigned long irq_flags;
+
+ if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
+ return;
+
+ event = ring_buffer_lock_reserve(global_trace.buffer, sizeof(*entry),
+ &irq_flags);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ tracing_generic_entry_update(&entry->ent, flags, pc);
+ entry->ent.type = TRACE_GRAPH_RET;
+ entry->ret = *trace;
ring_buffer_unlock_commit(global_trace.buffer, event, irq_flags);
}
#endif
@@ -1177,8 +1197,29 @@ function_trace_call(unsigned long ip, unsigned long parent_ip)
local_irq_restore(flags);
}
-#ifdef CONFIG_FUNCTION_RET_TRACER
-void trace_function_return(struct ftrace_retfunc *trace)
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+void trace_graph_entry(struct ftrace_graph_ent *trace)
+{
+ struct trace_array *tr = &global_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+ int pc;
+
+ raw_local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+ if (likely(disabled == 1)) {
+ pc = preempt_count();
+ __trace_graph_entry(tr, data, trace, flags, pc);
+ }
+ atomic_dec(&data->disabled);
+ raw_local_irq_restore(flags);
+}
+
+void trace_graph_return(struct ftrace_graph_ret *trace)
{
struct trace_array *tr = &global_trace;
struct trace_array_cpu *data;
@@ -1193,12 +1234,12 @@ void trace_function_return(struct ftrace_retfunc *trace)
disabled = atomic_inc_return(&data->disabled);
if (likely(disabled == 1)) {
pc = preempt_count();
- __trace_function_return(tr, data, trace, flags, pc);
+ __trace_graph_return(tr, data, trace, flags, pc);
}
atomic_dec(&data->disabled);
raw_local_irq_restore(flags);
}
-#endif /* CONFIG_FUNCTION_RET_TRACER */
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
static struct ftrace_ops trace_ops __read_mostly =
{
@@ -2000,9 +2041,11 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
trace_seq_print_cont(s, iter);
break;
}
- case TRACE_FN_RET: {
- return print_return_function(iter);
- break;
+ case TRACE_GRAPH_RET: {
+ return print_graph_function(iter);
+ }
+ case TRACE_GRAPH_ENT: {
+ return print_graph_function(iter);
}
case TRACE_BRANCH: {
struct trace_branch *field;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 4c453778a6a..f96f4e787ff 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -25,7 +25,8 @@ enum trace_type {
TRACE_BRANCH,
TRACE_BOOT_CALL,
TRACE_BOOT_RET,
- TRACE_FN_RET,
+ TRACE_GRAPH_RET,
+ TRACE_GRAPH_ENT,
TRACE_USER_STACK,
TRACE_BTS,
TRACE_POWER,
@@ -57,14 +58,16 @@ struct ftrace_entry {
unsigned long parent_ip;
};
+/* Function call entry */
+struct ftrace_graph_ent_entry {
+ struct trace_entry ent;
+ struct ftrace_graph_ent graph_ent;
+};
+
/* Function return entry */
-struct ftrace_ret_entry {
- struct trace_entry ent;
- unsigned long ip;
- unsigned long parent_ip;
- unsigned long long calltime;
- unsigned long long rettime;
- unsigned long overrun;
+struct ftrace_graph_ret_entry {
+ struct trace_entry ent;
+ struct ftrace_graph_ret ret;
};
extern struct tracer boot_tracer;
@@ -270,7 +273,10 @@ extern void __ftrace_bad_type(void);
IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
- IF_ASSIGN(var, ent, struct ftrace_ret_entry, TRACE_FN_RET);\
+ IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
+ TRACE_GRAPH_ENT); \
+ IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
+ TRACE_GRAPH_RET); \
IF_ASSIGN(var, ent, struct bts_entry, TRACE_BTS);\
IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
__ftrace_bad_type(); \
@@ -404,9 +410,9 @@ void trace_function(struct trace_array *tr,
unsigned long ip,
unsigned long parent_ip,
unsigned long flags, int pc);
-void
-trace_function_return(struct ftrace_retfunc *trace);
+void trace_graph_return(struct ftrace_graph_ret *trace);
+void trace_graph_entry(struct ftrace_graph_ent *trace);
void trace_bts(struct trace_array *tr,
unsigned long from,
unsigned long to);
@@ -451,6 +457,7 @@ struct tracer_switch_ops {
struct tracer_switch_ops *next;
};
+char *trace_find_cmdline(int pid);
#endif /* CONFIG_CONTEXT_SWITCH_TRACER */
#ifdef CONFIG_DYNAMIC_FTRACE
@@ -496,11 +503,11 @@ extern int trace_vprintk(unsigned long ip, const char *fmt, va_list args);
extern unsigned long trace_flags;
/* Standard output formatting function used for function return traces */
-#ifdef CONFIG_FUNCTION_RET_TRACER
-extern enum print_line_t print_return_function(struct trace_iterator *iter);
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+extern enum print_line_t print_graph_function(struct trace_iterator *iter);
#else
static inline enum print_line_t
-print_return_function(struct trace_iterator *iter)
+print_graph_function(struct trace_iterator *iter)
{
return TRACE_TYPE_UNHANDLED;
}
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
new file mode 100644
index 00000000000..d31d695174a
--- /dev/null
+++ b/kernel/trace/trace_functions_graph.c
@@ -0,0 +1,175 @@
+/*
+ *
+ * Function graph tracer.
+ * Copyright (c) 2008 Frederic Weisbecker <fweisbec@gmail.com>
+ * Mostly borrowed from function tracer which
+ * is Copyright (c) Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+#include <linux/ftrace.h>
+#include <linux/fs.h>
+
+#include "trace.h"
+
+#define TRACE_GRAPH_INDENT 2
+
+#define TRACE_GRAPH_PRINT_OVERRUN 0x1
+static struct tracer_opt trace_opts[] = {
+ /* Display overruns or not */
+ { TRACER_OPT(overrun, TRACE_GRAPH_PRINT_OVERRUN) },
+ { } /* Empty entry */
+};
+
+static struct tracer_flags tracer_flags = {
+ .val = 0, /* Don't display overruns by default */
+ .opts = trace_opts
+};
+
+/* pid on the last trace processed */
+static pid_t last_pid[NR_CPUS] = { [0 ... NR_CPUS-1] = -1 };
+
+static int graph_trace_init(struct trace_array *tr)
+{
+ int cpu, ret;
+
+ for_each_online_cpu(cpu)
+ tracing_reset(tr, cpu);
+
+ ret = register_ftrace_graph(&trace_graph_return,
+ &trace_graph_entry);
+ if (ret)
+ return ret;
+ tracing_start_cmdline_record();
+
+ return 0;
+}
+
+static void graph_trace_reset(struct trace_array *tr)
+{
+ tracing_stop_cmdline_record();
+ unregister_ftrace_graph();
+}
+
+/* If the pid changed since the last trace, output this event */
+static int verif_pid(struct trace_seq *s, pid_t pid, int cpu)
+{
+ char *comm;
+
+ if (last_pid[cpu] != -1 && last_pid[cpu] == pid)
+ return 1;
+
+ last_pid[cpu] = pid;
+ comm = trace_find_cmdline(pid);
+
+ return trace_seq_printf(s, "\nCPU[%03d]"
+ " ------------8<---------- thread %s-%d"
+ " ------------8<----------\n\n",
+ cpu, comm, pid);
+}
+
+static enum print_line_t
+print_graph_entry(struct ftrace_graph_ent *call, struct trace_seq *s,
+ struct trace_entry *ent, int cpu)
+{
+ int i;
+ int ret;
+
+ if (!verif_pid(s, ent->pid, cpu))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ ret = trace_seq_printf(s, "CPU[%03d] ", cpu);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) {
+ ret = trace_seq_printf(s, " ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ ret = seq_print_ip_sym(s, call->func, 0);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ ret = trace_seq_printf(s, "() {\n");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
+ struct trace_entry *ent, int cpu)
+{
+ int i;
+ int ret;
+
+ if (!verif_pid(s, ent->pid, cpu))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ ret = trace_seq_printf(s, "CPU[%03d] ", cpu);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ for (i = 0; i < trace->depth * TRACE_GRAPH_INDENT; i++) {
+ ret = trace_seq_printf(s, " ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ ret = trace_seq_printf(s, "} ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ ret = trace_seq_printf(s, "%llu\n", trace->rettime - trace->calltime);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERRUN) {
+ ret = trace_seq_printf(s, " (Overruns: %lu)\n",
+ trace->overrun);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+ return TRACE_TYPE_HANDLED;
+}
+
+enum print_line_t
+print_graph_function(struct trace_iterator *iter)
+{
+ struct trace_seq *s = &iter->seq;
+ struct trace_entry *entry = iter->ent;
+
+ switch (entry->type) {
+ case TRACE_GRAPH_ENT: {
+ struct ftrace_graph_ent_entry *field;
+ trace_assign_type(field, entry);
+ return print_graph_entry(&field->graph_ent, s, entry,
+ iter->cpu);
+ }
+ case TRACE_GRAPH_RET: {
+ struct ftrace_graph_ret_entry *field;
+ trace_assign_type(field, entry);
+ return print_graph_return(&field->ret, s, entry, iter->cpu);
+ }
+ default:
+ return TRACE_TYPE_UNHANDLED;
+ }
+}
+
+static struct tracer graph_trace __read_mostly = {
+ .name = "function-graph",
+ .init = graph_trace_init,
+ .reset = graph_trace_reset,
+ .print_line = print_graph_function,
+ .flags = &tracer_flags,
+};
+
+static __init int init_graph_trace(void)
+{
+ return register_tracer(&graph_trace);
+}
+
+device_initcall(init_graph_trace);
diff --git a/kernel/trace/trace_functions_return.c b/kernel/trace/trace_functions_return.c
deleted file mode 100644
index e00d64509c9..00000000000
--- a/kernel/trace/trace_functions_return.c
+++ /dev/null
@@ -1,98 +0,0 @@
-/*
- *
- * Function return tracer.
- * Copyright (c) 2008 Frederic Weisbecker <fweisbec@gmail.com>
- * Mostly borrowed from function tracer which
- * is Copyright (c) Steven Rostedt <srostedt@redhat.com>
- *
- */
-#include <linux/debugfs.h>
-#include <linux/uaccess.h>
-#include <linux/ftrace.h>
-#include <linux/fs.h>
-
-#include "trace.h"
-
-
-#define TRACE_RETURN_PRINT_OVERRUN 0x1
-static struct tracer_opt trace_opts[] = {
- /* Display overruns or not */
- { TRACER_OPT(overrun, TRACE_RETURN_PRINT_OVERRUN) },
- { } /* Empty entry */
-};
-
-static struct tracer_flags tracer_flags = {
- .val = 0, /* Don't display overruns by default */
- .opts = trace_opts
-};
-
-
-static int return_trace_init(struct trace_array *tr)
-{
- int cpu;
- for_each_online_cpu(cpu)
- tracing_reset(tr, cpu);
-
- return register_ftrace_return(&trace_function_return);
-}
-
-static void return_trace_reset(struct trace_array *tr)
-{
- unregister_ftrace_return();
-}
-
-
-enum print_line_t
-print_return_function(struct trace_iterator *iter)
-{
- struct trace_seq *s = &iter->seq;
- struct trace_entry *entry = iter->ent;
- struct ftrace_ret_entry *field;
- int ret;
-
- if (entry->type == TRACE_FN_RET) {
- trace_assign_type(field, entry);
- ret = trace_seq_printf(s, "%pF -> ", (void *)field->parent_ip);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- ret = seq_print_ip_sym(s, field->ip,
- trace_flags & TRACE_ITER_SYM_MASK);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- ret = trace_seq_printf(s, " (%llu ns)",
- field->rettime - field->calltime);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- if (tracer_flags.val & TRACE_RETURN_PRINT_OVERRUN) {
- ret = trace_seq_printf(s, " (Overruns: %lu)",
- field->overrun);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- }
-
- ret = trace_seq_printf(s, "\n");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- return TRACE_TYPE_HANDLED;
- }
- return TRACE_TYPE_UNHANDLED;
-}
-
-static struct tracer return_trace __read_mostly = {
- .name = "return",
- .init = return_trace_init,
- .reset = return_trace_reset,
- .print_line = print_return_function,
- .flags = &tracer_flags,
-};
-
-static __init int init_return_trace(void)
-{
- return register_tracer(&return_trace);
-}
-
-device_initcall(init_return_trace);