On Sat, Mar 15, 2014 at 05:45:51AM +0000, AKASHI Takahiro wrote: > This patch allows "dynamic ftrace" if CONFIG_DYNAMIC_FTRACE is enabled. > Here we can turn on and off tracing dynamically per-function base. > > On arm64, this is done by patching single branch instruction to _mcount() > inserted by gcc -pg option. The branch is replaced to NOP initially at > kernel start up, and later on, NOP to branch to ftrace_caller() when > enabled or branch to NOP when disabled. > Please note that ftrace_caller() is a counterpart of _mcount() in case of > 'static' ftrace. > > More details on architecture specific requirements are described in > Documentation/trace/ftrace-design.txt. > > Signed-off-by: AKASHI Takahiro <[email protected]>
Acked-by: Will Deacon <[email protected]> Will -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
