Messages in this thread | | | From | Jianlin Lv <> | Date | Fri, 23 Dec 2022 12:52:18 +0800 | Subject | Re: [PATCH] tracepoint: Allow livepatch module add trace event |
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On Tue, Nov 15, 2022 at 11:17 PM Steven Rostedt <rostedt@goodmis.org> wrote: > > On Wed, 16 Nov 2022 00:07:07 +0900 > Masami Hiramatsu (Google) <mhiramat@kernel.org> wrote: > > > BTW, now the kprobe_ftrace_handler() uses ftrace_test_recursion_trylock() > > to avoid ftrace recursion, is that OK for this case? > > Note, the ftrace_test_recursion_trylock() only prevents "same context" > recursion. That is, it will not let normal context recurse into normal > context, or interrupt context recurse into interrupt context. > > It has the logic of breaking up into 4 levels: > > 1. normal > 2. softirq > 3. irq > 4. NMI > > It allows the high levels to recurse into lower levels > (e.g. irq context into normal context) > > Thus, the code within the ftrace_test_recursion_trylock() must itself be > re-entrant to handle being called from different contexts. > > -- Steve
hi, Steve Any other comments for code changes? Is it possible for this patch to be merged?
Regards, Jianlin
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