Commit 2f754e77 authored by Steven Rostedt (VMware)'s avatar Steven Rostedt (VMware)
Browse files

tracing: Have the error logs show up in the proper instances 



As each instance has their own error_log file, it makes more sense that the
instances show the errors of their own instead of all error_logs having the
same data. Make it that the errors show up in the instance error_log file
that the error happens in. If no instance trace_array is available, then
NULL can be passed in which will create the error in the top level instance
(the one at the top of the tracefs directory).

Reviewed-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: default avatarTom Zanussi <tom.zanussi@linux.intel.com>
Tested-by: default avatarTom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent d0cd871b

kernel/trace/trace.c

+37 −18
Original line number Diff line number Diff line
@@ -6897,25 +6897,22 @@ struct tracing_log_err { 
	char			cmd[MAX_FILTER_STR_VAL]; /* what caused err */

};



static LIST_HEAD(tracing_err_log);

static DEFINE_MUTEX(tracing_err_log_lock);



static unsigned int n_tracing_err_log_entries;



struct tracing_log_err *get_tracing_log_err(void)

struct tracing_log_err *get_tracing_log_err(struct trace_array *tr)

{

	struct tracing_log_err *err;



	if (n_tracing_err_log_entries < TRACING_LOG_ERRS_MAX) {

	if (tr->n_err_log_entries < TRACING_LOG_ERRS_MAX) {

		err = kzalloc(sizeof(*err), GFP_KERNEL);

		if (!err)

			err = ERR_PTR(-ENOMEM);

		n_tracing_err_log_entries++;

		tr->n_err_log_entries++;



		return err;

	}



	err = list_first_entry(&tracing_err_log, struct tracing_log_err, list);

	err = list_first_entry(&tr->err_log, struct tracing_log_err, list);

	list_del(&err->list);



	return err;
@@ -6949,6 +6946,7 @@ unsigned int err_pos(char *cmd, const char *str) 


/**

 * tracing_log_err - write an error to the tracing error log

 * @tr: The associated trace array for the error (NULL for top level array)

 * @loc: A string describing where the error occurred

 * @cmd: The tracing command that caused the error

 * @errs: The array of loc-specific static error strings
@@ -6973,13 +6971,17 @@ unsigned int err_pos(char *cmd, const char *str) 
 * existing callers for examples of how static strings are typically

 * defined for use with tracing_log_err().

 */

void tracing_log_err(const char *loc, const char *cmd,

void tracing_log_err(struct trace_array *tr,

		     const char *loc, const char *cmd,

		     const char **errs, u8 type, u8 pos)

{

	struct tracing_log_err *err;



	if (!tr)

		tr = &global_trace;



	mutex_lock(&tracing_err_log_lock);

	err = get_tracing_log_err();

	err = get_tracing_log_err(tr);

	if (PTR_ERR(err) == -ENOMEM) {

		mutex_unlock(&tracing_err_log_lock);

		return;
@@ -6993,34 +6995,38 @@ void tracing_log_err(const char *loc, const char *cmd, 
	err->info.pos = pos;

	err->info.ts = local_clock();



	list_add_tail(&err->list, &tracing_err_log);

	list_add_tail(&err->list, &tr->err_log);

	mutex_unlock(&tracing_err_log_lock);

}



static void clear_tracing_err_log(void)

static void clear_tracing_err_log(struct trace_array *tr)

{

	struct tracing_log_err *err, *next;



	mutex_lock(&tracing_err_log_lock);

	list_for_each_entry_safe(err, next, &tracing_err_log, list) {

	list_for_each_entry_safe(err, next, &tr->err_log, list) {

		list_del(&err->list);

		kfree(err);

	}



	n_tracing_err_log_entries = 0;

	tr->n_err_log_entries = 0;

	mutex_unlock(&tracing_err_log_lock);

}



static void *tracing_err_log_seq_start(struct seq_file *m, loff_t *pos)

{

	struct trace_array *tr = m->private;



	mutex_lock(&tracing_err_log_lock);



	return seq_list_start(&tracing_err_log, *pos);

	return seq_list_start(&tr->err_log, *pos);

}



static void *tracing_err_log_seq_next(struct seq_file *m, void *v, loff_t *pos)

{

	return seq_list_next(v, &tracing_err_log, pos);

	struct trace_array *tr = m->private;



	return seq_list_next(v, &tr->err_log, pos);

}



static void tracing_err_log_seq_stop(struct seq_file *m, void *v)
@@ -7067,15 +7073,25 @@ static const struct seq_operations tracing_err_log_seq_ops = { 


static int tracing_err_log_open(struct inode *inode, struct file *file)

{

	struct trace_array *tr = inode->i_private;

	int ret = 0;



	if (trace_array_get(tr) < 0)

		return -ENODEV;



	/* If this file was opened for write, then erase contents */

	if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC))

		clear_tracing_err_log();

		clear_tracing_err_log(tr);



	if (file->f_mode & FMODE_READ)

	if (file->f_mode & FMODE_READ) {

		ret = seq_open(file, &tracing_err_log_seq_ops);



		if (!ret) {

			struct seq_file *m = file->private_data;

			m->private = tr;

		} else {

			trace_array_put(tr);

		}

	}

	return ret;

}
@@ -7091,6 +7107,7 @@ static const struct file_operations tracing_err_log_fops = { 
	.write		= tracing_err_log_write,

	.read           = seq_read,

	.llseek         = seq_lseek,

	.release	= tracing_release_generic_tr,

};



static int tracing_buffers_open(struct inode *inode, struct file *filp)
@@ -8293,6 +8310,7 @@ struct trace_array *trace_array_create(const char *name) 
	INIT_LIST_HEAD(&tr->systems);

	INIT_LIST_HEAD(&tr->events);

	INIT_LIST_HEAD(&tr->hist_vars);

	INIT_LIST_HEAD(&tr->err_log);



	if (allocate_trace_buffers(tr, trace_buf_size) < 0)

		goto out_free_tr;
@@ -9087,6 +9105,7 @@ __init static int tracer_alloc_buffers(void) 
	INIT_LIST_HEAD(&global_trace.systems);

	INIT_LIST_HEAD(&global_trace.events);

	INIT_LIST_HEAD(&global_trace.hist_vars);

	INIT_LIST_HEAD(&global_trace.err_log);

	list_add(&global_trace.list, &ftrace_trace_arrays);



	apply_trace_boot_options();

kernel/trace/trace.h

+4 −1
Original line number Diff line number Diff line
@@ -293,11 +293,13 @@ struct trace_array { 
	int			nr_topts;

	bool			clear_trace;

	int			buffer_percent;

	unsigned int		n_err_log_entries;

	struct tracer		*current_trace;

	unsigned int		trace_flags;

	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];

	unsigned int		flags;

	raw_spinlock_t		start_lock;

	struct list_head	err_log;

	struct dentry		*dir;

	struct dentry		*options;

	struct dentry		*percpu_dir;
@@ -1886,7 +1888,8 @@ extern ssize_t trace_parse_run_command(struct file *file, 
		int (*createfn)(int, char**));



extern unsigned int err_pos(char *cmd, const char *str);

extern void tracing_log_err(const char *loc, const char *cmd,

extern void tracing_log_err(struct trace_array *tr,

			    const char *loc, const char *cmd,

			    const char **errs, u8 type, u8 pos);



/*

kernel/trace/trace_events_filter.c

+2 −2
Original line number Diff line number Diff line
@@ -949,12 +949,12 @@ static void append_filter_err(struct trace_array *tr, 
	if (pe->lasterr > 0) {

		trace_seq_printf(s, "\n%*s", pos, "^");

		trace_seq_printf(s, "\nparse_error: %s\n", err_text[pe->lasterr]);

		tracing_log_err("event filter parse error",

		tracing_log_err(tr, "event filter parse error",

				filter->filter_string, err_text,

				pe->lasterr, pe->lasterr_pos);

	} else {

		trace_seq_printf(s, "\nError: (%d)\n", pe->lasterr);

		tracing_log_err("event filter parse error",

		tracing_log_err(tr, "event filter parse error",

				filter->filter_string, err_text,

				FILT_ERR_ERRNO, 0);

	}

kernel/trace/trace_events_hist.c

+2 −1
Original line number Diff line number Diff line
@@ -621,7 +621,8 @@ static void last_cmd_set(struct trace_event_file *file, char *str) 


static void hist_err(struct trace_array *tr, u8 err_type, u8 err_pos)

{

	tracing_log_err(last_cmd_loc, last_cmd, err_text, err_type, err_pos);

	tracing_log_err(tr, last_cmd_loc, last_cmd, err_text,

			err_type, err_pos);

}



static void hist_err_clear(void)

kernel/trace/trace_probe.c

+1 −1
Original line number Diff line number Diff line
@@ -186,7 +186,7 @@ void __trace_probe_log_err(int offset, int err_type) 
	}

	*(p - 1) = '\0';



	tracing_log_err(trace_probe_log.subsystem, command,

	tracing_log_err(NULL, trace_probe_log.subsystem, command,

			trace_probe_err_text, err_type, pos + offset);



	kfree(command);

CRA Git | Maintained and supported by SUSTech CRA and CCSE