[PATCH 08/13 v2] USB: mtu3: tracing: Use the new __vstring() helper

Steven Rostedt rostedt at goodmis.org
Thu Jul 14 06:38:57 PDT 2022


From d6485fe54bd4f04256a8500156a7c05cb3fb9592 Mon Sep 17 00:00:00 2001
From: "Steven Rostedt (Google)" <rostedt at goodmis.org>
Date: Tue, 5 Jul 2022 18:45:01 -0400
Subject: [PATCH] USB: mtu3: tracing: Use the new __vstring() helper

Instead of open coding a __dynamic_array() with a fixed length (which
defeats the purpose of the dynamic array in the first place). Use the new
__vstring() helper that will use a va_list and only write enough of the
string into the ring buffer that is needed.

Link: https://lkml.kernel.org/r/20220705224750.354926535@goodmis.org

Cc: Chunfeng Yun <chunfeng.yun at mediatek.com>
Cc: Ingo Molnar <mingo at kernel.org>
Cc: Andrew Morton <akpm at linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Cc: linux-usb at vger.kernel.org
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-mediatek at lists.infradead.org
Signed-off-by: Steven Rostedt (Google) <rostedt at goodmis.org>
---

Changes since v1: remove ',' that fails the build.

 drivers/usb/mtu3/mtu3_trace.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/mtu3/mtu3_trace.h b/drivers/usb/mtu3/mtu3_trace.h
index 1b897636daf2..ef3c17e2f8a6 100644
--- a/drivers/usb/mtu3/mtu3_trace.h
+++ b/drivers/usb/mtu3/mtu3_trace.h
@@ -25,11 +25,11 @@ TRACE_EVENT(mtu3_log,
 	TP_ARGS(dev, vaf),
 	TP_STRUCT__entry(
 		__string(name, dev_name(dev))
-		__dynamic_array(char, msg, MTU3_MSG_MAX)
+		__vstring(msg, vaf->fmt, vaf->va)
 	),
 	TP_fast_assign(
 		__assign_str(name, dev_name(dev));
-		vsnprintf(__get_str(msg), MTU3_MSG_MAX, vaf->fmt, *vaf->va);
+		__assign_vstr(msg, vaf->fmt, vaf->va);
 	),
 	TP_printk("%s: %s", __get_str(name), __get_str(msg))
 );
-- 
2.35.1




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