diff options
Diffstat (limited to 'kernel/trace/trace_functions.c')
| -rw-r--r-- | kernel/trace/trace_functions.c | 143 |
1 files changed, 41 insertions, 102 deletions
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c index 5b781d2be383..38fe1483c508 100644 --- a/kernel/trace/trace_functions.c +++ b/kernel/trace/trace_functions.c @@ -13,106 +13,32 @@ #include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/ftrace.h> -#include <linux/slab.h> #include <linux/fs.h> #include "trace.h" -static void tracing_start_function_trace(struct trace_array *tr); -static void tracing_stop_function_trace(struct trace_array *tr); -static void -function_trace_call(unsigned long ip, unsigned long parent_ip, - struct ftrace_ops *op, struct pt_regs *pt_regs); -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 */ -enum { - TRACE_FUNC_OPT_STACK = 0x1, -}; - -static int allocate_ftrace_ops(struct trace_array *tr) -{ - struct ftrace_ops *ops; - - ops = kzalloc(sizeof(*ops), GFP_KERNEL); - if (!ops) - return -ENOMEM; +/* function tracing enabled */ +static int ftrace_function_enabled; - /* Currently only the non stack verision is supported */ - ops->func = function_trace_call; - ops->flags = FTRACE_OPS_FL_RECURSION_SAFE; - - tr->ops = ops; - ops->private = tr; - return 0; -} - - -int ftrace_create_function_files(struct trace_array *tr, - struct dentry *parent) -{ - int ret; - - /* The top level array uses the "global_ops". */ - if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL)) { - ret = allocate_ftrace_ops(tr); - if (ret) - return ret; - } - - ftrace_create_filter_files(tr->ops, parent); - - return 0; -} +static struct trace_array *func_trace; -void ftrace_destroy_function_files(struct trace_array *tr) -{ - ftrace_destroy_filter_files(tr->ops); - kfree(tr->ops); - tr->ops = NULL; -} +static void tracing_start_function_trace(void); +static void tracing_stop_function_trace(void); 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; - } - - 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. - */ - return -ENOMEM; - } - + func_trace = tr; tr->trace_buffer.cpu = get_cpu(); put_cpu(); tracing_start_cmdline_record(); - tracing_start_function_trace(tr); + tracing_start_function_trace(); return 0; } static void function_trace_reset(struct trace_array *tr) { - tracing_stop_function_trace(tr); + tracing_stop_function_trace(); tracing_stop_cmdline_record(); } @@ -121,18 +47,25 @@ static void function_trace_start(struct trace_array *tr) tracing_reset_online_cpus(&tr->trace_buffer); } +/* Our option */ +enum { + TRACE_FUNC_OPT_STACK = 0x1, +}; + +static struct tracer_flags func_flags; + static void function_trace_call(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct pt_regs *pt_regs) { - struct trace_array *tr = op->private; + struct trace_array *tr = func_trace; struct trace_array_cpu *data; unsigned long flags; int bit; int cpu; int pc; - if (unlikely(!tr->function_enabled)) + if (unlikely(!ftrace_function_enabled)) return; pc = preempt_count(); @@ -158,14 +91,14 @@ static void function_stack_trace_call(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct pt_regs *pt_regs) { - struct trace_array *tr = op->private; + struct trace_array *tr = func_trace; struct trace_array_cpu *data; unsigned long flags; long disabled; int cpu; int pc; - if (unlikely(!tr->function_enabled)) + if (unlikely(!ftrace_function_enabled)) return; /* @@ -195,6 +128,7 @@ 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, @@ -219,21 +153,29 @@ static struct tracer_flags func_flags = { .opts = func_opts }; -static void tracing_start_function_trace(struct trace_array *tr) +static void tracing_start_function_trace(void) { - tr->function_enabled = 0; - register_ftrace_function(tr->ops); - tr->function_enabled = 1; + ftrace_function_enabled = 0; + + if (func_flags.val & TRACE_FUNC_OPT_STACK) + register_ftrace_function(&trace_stack_ops); + else + register_ftrace_function(&trace_ops); + + ftrace_function_enabled = 1; } -static void tracing_stop_function_trace(struct trace_array *tr) +static void tracing_stop_function_trace(void) { - tr->function_enabled = 0; - unregister_ftrace_function(tr->ops); + ftrace_function_enabled = 0; + + if (func_flags.val & TRACE_FUNC_OPT_STACK) + unregister_ftrace_function(&trace_stack_ops); + else + unregister_ftrace_function(&trace_ops); } -static int -func_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) +static int func_set_flag(u32 old_flags, u32 bit, int set) { switch (bit) { case TRACE_FUNC_OPT_STACK: @@ -241,14 +183,12 @@ func_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) if (!!set == !!(func_flags.val & TRACE_FUNC_OPT_STACK)) break; - unregister_ftrace_function(tr->ops); - if (set) { - tr->ops = &trace_stack_ops; - register_ftrace_function(tr->ops); + unregister_ftrace_function(&trace_ops); + register_ftrace_function(&trace_stack_ops); } else { - tr->ops = &trace_ops; - register_ftrace_function(tr->ops); + unregister_ftrace_function(&trace_stack_ops); + register_ftrace_function(&trace_ops); } break; @@ -268,7 +208,6 @@ static struct tracer function_trace __tracer_data = .wait_pipe = poll_wait_pipe, .flags = &func_flags, .set_flag = func_set_flag, - .allow_instances = true, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_function, #endif |