Resending, fixed the subject. changelog --------- v2 - v3 - Addressed comment from Thomas Gleixner - Timestamps are available a little later in boot but still much earlier than in mainline. This significantly simplified this work. v1 - v2 In patch "x86/tsc: tsc early": - added tsc_adjusted_early() - fixed 32-bit compile error use do_div()
Adding early boot time stamps support for x86 machines. SPARC patches for early boot time stamps are already integrated into mainline linux. Sample output ------------- Before: https://hastebin.com/jadaqukubu.scala After: https://hastebin.com/nubipozacu.scala As seen above, currently timestamps are available from around the time when "Security Framework" is initialized. But, 26s already passed until we reached to this point. Pavel Tatashin (2): sched/clock: interface to allow timestamps early in boot x86/tsc: use tsc early arch/x86/include/asm/tsc.h | 4 +++ arch/x86/kernel/setup.c | 10 ++++++-- arch/x86/kernel/time.c | 22 ++++++++++++++++ arch/x86/kernel/tsc.c | 47 ++++++++++++++++++++++++++++++++++ include/linux/sched/clock.h | 4 +++ kernel/sched/clock.c | 61 ++++++++++++++++++++++++++++++++++++++++++++- 6 files changed, 145 insertions(+), 3 deletions(-) -- 2.14.0