arm64: ftrace: Set FTRACE_MAY_SLEEP before ftrace_modify_all_code()
It has been reported that ftrace_replace_code() which is called by ftrace_modify_all_code() can cause a soft lockup warning for an allmodconfig kernel. This is because all the debug options enabled causes the loop in ftrace_replace_code() (which loops over all the functions being enabled where there can be 10s of thousands), is too slow, and never schedules out. To solve this, setting FTRACE_MAY_SLEEP to the command passed into ftrace_replace_code() will make it call cond_resched() in the loop, which prevents the soft lockup warning from triggering. Link: http://lkml.kernel.org/r/20181204192903.8193-1-anders.roxell@linaro.org Link: http://lkml.kernel.org/r/20181205183304.000714627@goodmis.orgAcked-by: Will Deacon <will.deacon@arm.com> Reported-by: Anders Roxell <anders.roxell@linaro.org> Tested-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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