2014-11-15 05:12:00

by Steven Rostedt

Subject: [PATCH 07/26 v5] kprobes/tracing: Use trace_seq_has_overflowed() for overflow checks

From: "Steven Rostedt (Red Hat)" <[email protected]>

Instead of checking the return value of trace_seq_printf() and friends
for overflowing of the buffer, use the trace_seq_has_overflowed() helper
function.

This cleans up the code quite a bit and also takes us a step closer to
changing the return values of trace_seq_printf() and friends to void.

Link: http://lkml.kernel.org/r/[email protected]

Reviewed-by: Srikar Dronamraju <[email protected]>
Acked-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
---
kernel/trace/trace_kprobe.c | 42 ++++++++++++++++--------------------------
1 file changed, 16 insertions(+), 26 deletions(-)

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index ef7e7f16ed1a..5edb518be345 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1024,27 +1024,22 @@ print_kprobe_event(struct trace_iterator *iter, int flags,
field = (struct kprobe_trace_entry_head *)iter->ent;
tp = container_of(event, struct trace_probe, call.event);

- if (!trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call)))
- goto partial;
+ trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call));

if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
- goto partial;
+ goto out;

- if (!trace_seq_putc(s, ')'))
- goto partial;
+ trace_seq_putc(s, ')');

data = (u8 *)&field[1];
for (i = 0; i < tp->nr_args; i++)
if (!tp->args[i].type->print(s, tp->args[i].name,
data + tp->args[i].offset, field))
- goto partial;
-
- if (!trace_seq_putc(s, '\n'))
- goto partial;
+ goto out;

- return TRACE_TYPE_HANDLED;
-partial:
- return TRACE_TYPE_PARTIAL_LINE;
+ trace_seq_putc(s, '\n');
+ out:
+ return trace_handle_return(s);
}

static enum print_line_t
@@ -1060,33 +1055,28 @@ print_kretprobe_event(struct trace_iterator *iter, int flags,
field = (struct kretprobe_trace_entry_head *)iter->ent;
tp = container_of(event, struct trace_probe, call.event);

- if (!trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call)))
- goto partial;
+ trace_seq_printf(s, "%s: (", ftrace_event_name(&tp->call));

if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
- goto partial;
+ goto out;

- if (!trace_seq_puts(s, " <- "))
- goto partial;
+ trace_seq_puts(s, " <- ");

if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET))
- goto partial;
+ goto out;

- if (!trace_seq_putc(s, ')'))
- goto partial;
+ trace_seq_putc(s, ')');

data = (u8 *)&field[1];
for (i = 0; i < tp->nr_args; i++)
if (!tp->args[i].type->print(s, tp->args[i].name,
data + tp->args[i].offset, field))
- goto partial;
+ goto out;

- if (!trace_seq_putc(s, '\n'))
- goto partial;
+ trace_seq_putc(s, '\n');

- return TRACE_TYPE_HANDLED;
-partial:
- return TRACE_TYPE_PARTIAL_LINE;
+ out:
+ return trace_handle_return(s);
}


--
2.1.1

2014-11-18 14:02:47

by Petr Mladek

Subject: Re: [PATCH 07/26 v5] kprobes/tracing: Use trace_seq_has_overflowed() for overflow checks

On Fri 2014-11-14 23:58:54, Steven Rostedt wrote:
> From: "Steven Rostedt (Red Hat)" <[email protected]>
>
> Instead of checking the return value of trace_seq_printf() and friends
> for overflowing of the buffer, use the trace_seq_has_overflowed() helper
> function.
>
> This cleans up the code quite a bit and also takes us a step closer to
> changing the return values of trace_seq_printf() and friends to void.
>
> Link: http://lkml.kernel.org/r/[email protected]
>
> Reviewed-by: Srikar Dronamraju <[email protected]>
> Acked-by: Masami Hiramatsu <[email protected]>
> Signed-off-by: Steven Rostedt <[email protected]>

Reviewed-by: Petr Mladek <[email protected]>

Best Regards,
Petr