Re: [PATCH v8 2/5] tracing: Use the stackmap from the ftrace stack recording path

On Sun, 08 Nov 2026 06:35:01 +0800, kernel test robot wrote:

kernel/trace/trace.c: In function 'record_stackmap':
include/linux/rcupdate.h:502:9: error: dereferencing pointer to incomplete type 'struct ftrace_stackmap'

struct ftrace_stackmap is only defined in trace_stackmap.c, and GCC
before 10 rejects typeof(*p) on the incomplete type in
rcu_dereference_sched(). I reproduced it with GCC 8.5.

v9 will move the rcu_dereference_sched() into
ftrace_stackmap_get_cookie(), which will take the trace_array instead
of the map.

-- Pengfei