From 2f754e771b1a6feba670782e82c45555984ac43b Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Mon, 1 Apr 2019 22:52:21 -0400 Subject: 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: Masami Hiramatsu Reviewed-by: Tom Zanussi Tested-by: Tom Zanussi Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace.c | 55 +++++++++++++++++++++++++------------- kernel/trace/trace.h | 5 +++- kernel/trace/trace_events_filter.c | 4 +-- kernel/trace/trace_events_hist.c | 3 ++- kernel/trace/trace_probe.c | 2 +- 5 files changed, 46 insertions(+), 23 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 7978168f5041..3d55e9daae8c 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -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(); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 809c5d7f0064..da00a3d508c1 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -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); /* diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 2b63930cd3e6..180ecb390baa 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -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); } diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index a167e439e9a1..a1136e043f17 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -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) diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index e11f98c49d72..4cc2d467d34c 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -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); -- cgit