4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Arnd Bergmann <arnd@xxxxxxxx>
[ Upstream commit 5281ec83454d70d98b71f1836fb16512566c01cd ]
When CONFIG_PERF_EVENTS, a 'make W=1' build produces a warning about the
unused ftrace_event_id_fops variable:
kernel/trace/trace_events.c:2155:37: error: 'ftrace_event_id_fops' defined but not used [-Werror=unused-const-variable=]
2155 | static const struct file_operations ftrace_event_id_fops = {
Hide this in the same #ifdef as the reference to it.
Link: https://lore.kernel.org/linux-trace-kernel/20240403080702.3509288-7-arnd@xxxxxxxxxx
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Cc: Zheng Yejian <zhengyejian1@xxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Ajay Kaher <akaher@xxxxxxxxxx>
Cc: Jinjie Ruan <ruanjinjie@xxxxxxxxxx>
Cc: Clément Léger <cleger@xxxxxxxxxxxx>
Cc: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Cc: "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@xxxxxxxxx>
Fixes: 620a30e97feb ("tracing: Don't pass file_operations array to event_create_dir()")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
kernel/trace/trace_events.c | 4 ++++
1 file changed, 4 insertions(+)
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1309,6 +1309,7 @@ static int trace_format_open(struct inod
return 0;
}
+#ifdef CONFIG_PERF_EVENTS
static ssize_t
event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
{
@@ -1323,6 +1324,7 @@ event_id_read(struct file *filp, char __
return simple_read_from_buffer(ubuf, cnt, ppos, buf, len);
}
+#endif
static ssize_t
event_filter_read(struct file *filp, char __user *ubuf, size_t cnt,
@@ -1727,10 +1729,12 @@ static const struct file_operations ftra
.release = seq_release,
};
+#ifdef CONFIG_PERF_EVENTS
static const struct file_operations ftrace_event_id_fops = {
.read = event_id_read,
.llseek = default_llseek,
};
+#endif
static const struct file_operations ftrace_event_filter_fops = {
.open = tracing_open_generic,
