Commit-ID: 4763f03d3d186ce8a1125844790152d76804ad60 Gitweb: https://git.kernel.org/tip/4763f03d3d186ce8a1125844790152d76804ad60 Author: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> AuthorDate: Thu, 19 Jul 2018 16:55:40 -0400 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitDate: Fri, 20 Jul 2018 00:02:42 +0200 x86/tsc: Use TSC as sched clock early All prerequesites for enabling TSC as sched clock early in the boot process are available now: - Early attempt of TSC calibration - Early availablity of static branch patching If TSC frequency can be established in the early calibration, enable the static key which switches sched clock to use TSC. [ tglx: Massaged changelog ] Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: steven.sistare@xxxxxxxxxx Cc: daniel.m.jordan@xxxxxxxxxx Cc: linux@xxxxxxxxxxxxxxx Cc: schwidefsky@xxxxxxxxxx Cc: heiko.carstens@xxxxxxxxxx Cc: john.stultz@xxxxxxxxxx Cc: sboyd@xxxxxxxxxxxxxx Cc: hpa@xxxxxxxxx Cc: douly.fnst@xxxxxxxxxxxxxx Cc: peterz@xxxxxxxxxxxxx Cc: prarit@xxxxxxxxxx Cc: feng.tang@xxxxxxxxx Cc: pmladek@xxxxxxxx Cc: gnomes@xxxxxxxxxxxxxxxxxxx Cc: linux-s390@xxxxxxxxxxxxxxx Cc: boris.ostrovsky@xxxxxxxxxx Cc: jgross@xxxxxxxx Cc: pbonzini@xxxxxxxxxx Link: https://lkml.kernel.org/r/20180719205545.16512-22-pasha.tatashin@xxxxxxxxxx --- arch/x86/kernel/tsc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 7ea0718a4c75..9277ae9b68b3 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -1408,6 +1408,7 @@ void __init tsc_early_init(void) /* Sanitize TSC ADJUST before cyc2ns gets initialized */ tsc_store_and_check_tsc_adjust(true); cyc2ns_init_boot_cpu(); + static_branch_enable(&__use_tsc); } void __init tsc_init(void) -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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