Support for -fentry -mrecord-mcount and -mnop-mcount has been added for s390 in gcc master branch. An attempt to build 4.18 for s390 with that gcc would produce a kernel with no __mcount_loc though because of the new condition in scripts/Makefile.build:210 which disables recordmcount tool if compiler supports -mrecord-mcount (s390 relies on combination of -mhotpatch=0,3 gcc flag and recordmcount.pl). This patch series adds s390 ftrace support based on combination of -pg -fentry -mrecord-mcount and -mnop-mcount gcc flags (that fixes issue mentioned above). At the same time this patch series fixes couple of minor issues and adds -mnop-mcount gcc flag support (utilized by s390). Vasily Gorbik (4): trace: handle CC_FLAGS_FTRACE more accurately trace: avoid calling cc-option -mrecord-mcount for every Makefile trace: add -mcount-nop option support s390/ftrace: add -mfentry and -mnop-mcount support Makefile | 24 ++++++++++++++++++++---- arch/s390/Kconfig | 2 ++ arch/s390/Makefile | 16 +++++++++------- arch/s390/include/asm/ftrace.h | 6 +++--- arch/s390/kernel/ftrace.c | 2 +- arch/s390/kernel/mcount.S | 2 +- kernel/trace/Kconfig | 5 +++++ kernel/trace/ftrace.c | 2 ++ scripts/Makefile.build | 9 +++------ 9 files changed, 46 insertions(+), 22 deletions(-) -- 2.18.0.13.gd42ae10 -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html