On 2021/10/12 下午1:39, 王贇 wrote: > The testing show that perf_ftrace_function_call() are using > smp_processor_id() with preemption enabled, all the checking > on CPU could be wrong after preemption, PATCH 1/2 will fix > that. 2/2 actually. > > Besides, as Peter point out, the testing of recursion within > the section between ftrace_test_recursion_trylock()/_unlock() > pair also need the preemption disabled as the documentation > explained, PATCH 2/2 will make sure on that. 1/2 actually... Regards, Michael Wang > > Michael Wang (2): > ftrace: disable preemption on the testing of recursion > ftrace: prevent preemption in perf_ftrace_function_call() > > arch/csky/kernel/probes/ftrace.c | 2 -- > arch/parisc/kernel/ftrace.c | 2 -- > arch/powerpc/kernel/kprobes-ftrace.c | 2 -- > arch/riscv/kernel/probes/ftrace.c | 2 -- > arch/x86/kernel/kprobes/ftrace.c | 2 -- > include/linux/trace_recursion.h | 10 +++++++++- > kernel/livepatch/patch.c | 6 ------ > kernel/trace/trace_event_perf.c | 17 +++++++++++++---- > kernel/trace/trace_functions.c | 5 ----- > 9 files changed, 22 insertions(+), 26 deletions(-) >
