[Crash-utility] [PATCH] extensions/trace: max_buffer is optional
max_buffer is optional in the kernel (depends on the
CONFIG_TRACE_MAX_TRACE option). Don't fail if it isn't available.
---
extensions/trace.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/extensions/trace.c b/extensions/trace.c
index 9f81568..c269f4c 100644
--- a/extensions/trace.c
+++ b/extensions/trace.c
@@ -34,6 +34,10 @@ static int encapsulated_current_trace;
* trace_buffer is supported
*/
static int trace_buffer_available;
+/*
+ * max_buffer is supported
+ */
+static int max_buffer_available;
#define koffset(struct, member) struct##_##member##_offset
@@ -163,8 +167,10 @@ static int init_offsets(void)
if (trace_buffer_available) {
init_offset(trace_array, trace_buffer);
- init_offset(trace_array, max_buffer);
init_offset(trace_buffer, buffer);
+
+ if (max_buffer_available)
+ init_offset(trace_array, max_buffer);
} else {
init_offset(trace_array, buffer);
}
@@ -448,6 +454,9 @@ out_fail:
static int ftrace_int_max_tr_trace(void)
{
if (trace_buffer_available) {
+ if (!max_buffer_available)
+ return 0;
+
global_max_buffer = global_trace + koffset(trace_array, max_buffer);
read_value(max_tr_ring_buffer, global_max_buffer, trace_buffer, buffer);
} else {
@@ -528,6 +537,9 @@ static int ftrace_init(void)
if (MEMBER_EXISTS("trace_array", "trace_buffer")) {
trace_buffer_available = 1;
+
+ if (MEMBER_EXISTS("trace_array", "max_buffer"))
+ max_buffer_available = 1;
} else {
sym_max_tr_trace = symbol_search("max_tr");
if (sym_max_tr_trace == NULL)
--
1.7.10.4