Hi,
I've just posted a patch 'ftrace: Remove unused list 'ftrace_direct_funcs''
that clears out some old code, but while at it I noticed the global
'ftrace_direct_func_count'.
As far as I can tell, it's never assigned (or initialised) but it is tested:
kernel/trace/fgraph.c:
#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
/*
* Skip graph tracing if the return location is served by direct trampoline,
* since call sequence and return addresses are unpredictable anyway.
* Ex: BPF trampoline may call original function and may skip frame
* depending on type of BPF programs attached.
*/
if (ftrace_direct_func_count &&
ftrace_find_rec_direct(ret - MCOUNT_INSN_SIZE))
return -EBUSY;
#endif
So I wasn't sure whether it was just safe to nuke that section
or whether it really needed fixing?
Dave
--
-----Open up your eyes, open up your mind, open up your code -------
/ Dr. David Alan Gilbert | Running GNU/Linux | Happy \
\ dave @ treblig.org | | In Hex /
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