__attribute__((section("_ftrace_annotated_branch"))) \
______f = { \
.func = __func__, \
.file = __FILE__, \
.line = __LINE__, \
}; \
______r = likely_notrace(x); \
ftrace_likely_update(&______f, ______r, expect); \
______r; \
})
函式ftrace_likely_update (位置在kernel/trace/trace_branch.c)实作如下所示,
void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect)
{
/*
* I would love to have a trace point here instead, but the
* trace point code is so inundated with unlikely and likely
* conditions that the recursive nightmare that exists is too
* much to try to get working. At least for now.
*/
trace_likely_condition(f, val, expect);
/* FIXME: Make this atomic! */
if (val == expect)
f->correct++;
else
f->incorrect++;
}