From 7eeafbcab47fe9860e5106286db83d60e3f35644 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Red Hat)" Date: Mon, 26 Jan 2015 21:00:48 -0500 Subject: [PATCH] tracing: Separate out initializing top level dir from instances The top level trace array is treated a little different than the instances, as it has to deal with more of the general tracing. The tr->dir is the tracing directory, which is an immutable dentry, where as the tr->dir of instances are the dentry that was created, and can be destroyed later. These should have different functions accessing them. As only tracing_init_dentry() deals with the top level array, fold the code for it into that function, and remove the trace_init_dentry_tr() that was also used by the instances to get their directory dentry. Add a tracing_get_dentry() to just get the tracing dir entry for instances as well as the top level array. Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 51 ++++++++++++++++++++++++++------------------ 1 file changed, 30 insertions(+), 21 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 2668a0d742ee..5afce60e1b68 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -5815,28 +5815,11 @@ static __init int register_snapshot_cmd(void) static inline __init int register_snapshot_cmd(void) { return 0; } #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ -static struct dentry *tracing_init_dentry_tr(struct trace_array *tr) +static struct dentry *tracing_get_dentry(struct trace_array *tr) { - if (tr->dir) - return tr->dir; - - if (!debugfs_initialized()) - return ERR_PTR(-ENODEV); - - if (tr->flags & TRACE_ARRAY_FL_GLOBAL) - tr->dir = debugfs_create_dir("tracing", NULL); - - if (!tr->dir) - pr_warn_once("Could not create debugfs directory 'tracing'\n"); - return tr->dir; } -struct dentry *tracing_init_dentry(void) -{ - return tracing_init_dentry_tr(&global_trace); -} - static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) { struct dentry *d_tracer; @@ -5844,7 +5827,7 @@ static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) if (tr->percpu_dir) return tr->percpu_dir; - d_tracer = tracing_init_dentry_tr(tr); + d_tracer = tracing_get_dentry(tr); if (IS_ERR(d_tracer)) return NULL; @@ -6047,7 +6030,7 @@ static struct dentry *trace_options_init_dentry(struct trace_array *tr) if (tr->options) return tr->options; - d_tracer = tracing_init_dentry_tr(tr); + d_tracer = tracing_get_dentry(tr); if (IS_ERR(d_tracer)) return NULL; @@ -6532,6 +6515,33 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) } +/** + * tracing_init_dentry - initialize top level trace array + * + * This is called when creating files or directories in the tracing + * directory. It is called via fs_initcall() by any of the boot up code + * and expects to return the dentry of the top level tracing directory. + */ +struct dentry *tracing_init_dentry(void) +{ + struct trace_array *tr = &global_trace; + + if (tr->dir) + return tr->dir; + + if (WARN_ON(!debugfs_initialized())) + return ERR_PTR(-ENODEV); + + tr->dir = debugfs_create_dir("tracing", NULL); + + if (!tr->dir) { + pr_warn_once("Could not create debugfs directory 'tracing'\n"); + return ERR_PTR(-ENOMEM); + } + + return tr->dir; +} + static __init int tracer_init_debugfs(void) { struct dentry *d_tracer; @@ -6772,7 +6782,6 @@ __init static int tracer_alloc_buffers(void) int ring_buf_size; int ret = -ENOMEM; - if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) goto out; -- 2.20.1