Currently, trace_seq_init may be called many times with the intent of
resetting the buffer. Add a function trace_seq_reset that does that and
replace the relevant occurrences to use it instead.
Suggested-by: Steven Rostedt <rost...@goodmis.org>
Signed-off-by: Ricardo B. Marliere <rica...@marliere.net>
---
include/linux/trace_seq.h | 11 +++++++++++
include/trace/trace_events.h | 2 +-
kernel/trace/trace.c | 10 +++++-----
kernel/trace/trace_output.c | 2 +-
kernel/trace/trace_seq.c | 2 +-
5 files changed, 19 insertions(+), 8 deletions(-)
diff --git a/include/linux/trace_seq.h b/include/linux/trace_seq.h
index 9ec229dfddaa..d3fa41001813 100644
--- a/include/linux/trace_seq.h
+++ b/include/linux/trace_seq.h
@@ -29,6 +29,17 @@ trace_seq_init(struct trace_seq *s)
s->readpos = 0;
}
+static inline void
+trace_seq_reset(struct trace_seq *s)
+{
+ if (WARN_ON_ONCE(!s->seq.size))
+ seq_buf_init(&s->seq, s->buffer, TRACE_SEQ_BUFFER_SIZE);
+ else
+ seq_buf_clear(&s->seq);
+ s->full = 0;
+ s->readpos = 0;
+}
+
/**
* trace_seq_used - amount of actual data written to buffer
* @s: trace sequence descriptor
diff --git a/include/trace/trace_events.h b/include/trace/trace_events.h
index c2f9cabf154d..2bc79998e5ab 100644
--- a/include/trace/trace_events.h
+++ b/include/trace/trace_events.h
@@ -227,7 +227,7 @@ trace_raw_output_##call(struct trace_iterator *iter, int
flags, \
\
field = (typeof(field))entry; \
\
- trace_seq_init(p); \
+ trace_seq_reset(p); \
return trace_output_call(iter, #call, print); \
} \
static struct trace_event_functions trace_event_type_funcs_##call = { \
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 9eddf8168df2..9827700d0164 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2928,7 +2928,7 @@ static void output_printk(struct trace_event_buffer
*fbuffer)
event = &fbuffer->trace_file->event_call->event;
raw_spin_lock_irqsave(&tracepoint_iter_lock, flags);
- trace_seq_init(&iter->seq);
+ trace_seq_reset(&iter->seq);
iter->ent = fbuffer->entry;
event_call->event.funcs->trace(iter, 0, event);
trace_seq_putc(&iter->seq, 0);
@@ -6925,7 +6925,7 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
if (sret != -EBUSY)
goto out;
- trace_seq_init(&iter->seq);
+ trace_seq_reset(&iter->seq);
if (iter->trace->read) {
sret = iter->trace->read(iter, filp, ubuf, cnt, ppos);
@@ -6998,7 +6998,7 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
/* Now copy what we have to the user */
sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
if (iter->seq.readpos >= trace_seq_used(&iter->seq))
- trace_seq_init(&iter->seq);
+ trace_seq_reset(&iter->seq);
/*
* If there was nothing to send to user, in spite of consuming trace
@@ -7130,7 +7130,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
spd.partial[i].offset = 0;
spd.partial[i].len = trace_seq_used(&iter->seq);
- trace_seq_init(&iter->seq);
+ trace_seq_reset(&iter->seq);
}
trace_access_unlock(iter->cpu_file);
@@ -10282,7 +10282,7 @@ trace_printk_seq(struct trace_seq *s)
printk(KERN_TRACE "%s", s->buffer);
- trace_seq_init(s);
+ trace_seq_reset(s);
}
void trace_init_global_iter(struct trace_iterator *iter)
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 3e7fa44dc2b2..c949e7736618 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -308,7 +308,7 @@ int trace_raw_output_prep(struct trace_iterator *iter,
return TRACE_TYPE_UNHANDLED;
}
- trace_seq_init(p);
+ trace_seq_reset(p);
trace_seq_printf(s, "%s: ", trace_event_name(event));
return trace_handle_return(s);
diff --git a/kernel/trace/trace_seq.c b/kernel/trace/trace_seq.c
index c158d65a8a88..741b2f3d76c0 100644
--- a/kernel/trace/trace_seq.c
+++ b/kernel/trace/trace_seq.c
@@ -59,7 +59,7 @@ int trace_print_seq(struct seq_file *m, struct trace_seq *s)
* do something else with the contents.
*/
if (!ret)
- trace_seq_init(s);
+ trace_seq_reset(s);
return ret;
}
--
2.43.0
