[PATCH] ftrace: set kernel_stack's caller size properly

From: Josef Bacik
Date: Wed Sep 24 2014 - 16:14:23 EST


I noticed when trying to use the trace-cmd python interface that reading the raw
buffer wasn't working for kernel_stack events. This is because it uses a
stubbed version of __dynamic_array that doesn't do the __data_loc trick and
encode the length of the array into the field. Instead it just shows up as a
size of 0. So change this to __array and set the len to FTRACE_STACK_ENTRIES
since this is what we actually do in practice and matches how user_stack_trace
works. Thanks,

Signed-off-by: Josef Bacik <jbacik@xxxxxx>
---
kernel/trace/trace_entries.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index e2d027a..52b5860 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -178,7 +178,7 @@ FTRACE_ENTRY(kernel_stack, stack_entry,

F_STRUCT(
__field( int, size )
- __dynamic_array(unsigned long, caller )
+ __array( unsigned long, caller, FTRACE_STACK_ENTRIES )
),

F_printk("\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
--
1.8.3.1

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