user/sven/linux.git/scripts/recordmcount.h, branch v3.2

ftrace/recordmcount: Avoid STT_FUNC symbols as base on ARM

2011-05-25T23:56:33Z

While find_secsym_ndx often finds the unamed local STT_SECTION, if a section has only one function in it, the ARM toolchain generates the STT_FUNC symbol before the STT_SECTION, and recordmcount finds this instead. This is problematic on ARM because in ARM ELFs, "if a [STT_FUNC] symbol addresses a Thumb instruction, its value is the address of the instruction with bit zero set (in a relocatable object, the section offset with bit zero set)". This leads to incorrect mcount addresses being recorded. Fix this by not using STT_FUNC symbols as the base on ARM. Signed-off-by: Rabin Vincent Link: http://lkml.kernel.org/r/1305134631-31617-1-git-send-email-rabin@rab.in Signed-off-by: Steven Rostedt

ftrace/recordmcount: mcount address adjustment

2011-05-16T18:53:22Z

Introduce mcount_adjust{,_32,_64} to the C implementation of recordmcount analog to $mcount_adjust in the perl script. The adjustment is added to the address of the relocations against the mcount symbol. If this adjustment is done by recordmcount at compile time the ftrace_call_adjust function can be turned into a nop. Cc: John Reiser Signed-off-by: Martin Schwidefsky Signed-off-by: Steven Rostedt

ftrace/recordmcount: Add helper function get_sym_str_and_relp()

2011-05-16T18:48:55Z

The code to get the symbol, string, and relp pointers in the two functions sift_rel_mcount() and nop_mcount() are identical and also non-trivial. Moving this duplicate code into a single helper function makes the code easier to read and more maintainable. Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023739.723658553@goodmis.org Signed-off-by: Steven Rostedt

ftrace/recordmcount: Remove duplicate code to find mcount symbol

2011-05-16T18:48:02Z

The code in sift_rel_mcount() and nop_mcount() to get the mcount symbol number is identical. Replace the two locations with a call to a function that does the work. Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023739.488093407@goodmis.org Signed-off-by: Steven Rostedt

ftrace/recordmcount: Add warning logic to warn on mcount not recorded

2011-05-16T18:44:20Z

There's some sections that should not have mcount recorded and should not have modifications to the that code. But currently they waste some time by calling mcount anyway (which simply returns). As the real answer should be to either whitelist the section or have gcc ignore it fully. This change adds a option to recordmcount to warn when it finds a section that is ignored by ftrace but still contains mcount callers. This is not on by default as developers may not know if the section should be completely ignored or added to the whitelist. Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023738.476989377@goodmis.org Signed-off-by: Steven Rostedt

ftrace/recordmcount: Make ignored mcount calls into nops at compile time

2011-05-16T18:43:32Z

There are sections that are ignored by ftrace for the function tracing because the text is in a section that can be removed without notice. The mcount calls in these sections are ignored and ftrace never sees them. The downside of this is that the functions in these sections still call mcount. Although the mcount function is defined in assembly simply as a return, this added overhead is unnecessary. The solution is to convert these callers into nops at compile time. A better solution is to add 'notrace' to the section markers, but as new sections come up all the time, it would be nice that they are delt with when they are created. Later patches will deal with finding these sections and doing the proper solution. Thanks to H. Peter Anvin for giving me the right nops to use for x86. Cc: "H. Peter Anvin" Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023738.237101176@goodmis.org Signed-off-by: Steven Rostedt

ftrace/recordmcount: Modify only executable sections

2011-05-16T18:42:56Z

PROGBITS is not enough to determine if the section should be modified or not. Only process sections that are marked as executable. Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023737.991485123@goodmis.org Signed-off-by: Steven Rostedt

ftrace/trivial: Clean up recordmcount.c to use Linux style comparisons

2011-05-16T18:38:51Z

The Linux ftrace subsystem style for comparing is: var == 1 var > 0 and not: 1 == var 0 < var It is considered that Linux developers are smart enough not to do the if (var = 1) mistake. Cc: John Reiser Link: http://lkml.kernel.org/r/20110421023737.290712238@goodmis.org Signed-off-by: Steven Rostedt

Merge branches 'ftrace', 'gic', 'io', 'kexec', 'mod', 'sa11x0', 'sh' and 'versatile' into devel

2011-01-05T18:08:10Z

ARM: 6511/1: ftrace: add ARM support for C version of recordmcount

2010-12-04T11:30:27Z

Depending on the compiler version, ARM GCC calls the mcount function either __gnu_mcount_nc or mcount. Acked-by: Steven Rostedt Signed-off-by: Rabin Vincent Signed-off-by: Russell King