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x86/tsc: Be consistent about use_tsc_delay()

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Currently loops_per_jiffy is set in tsc_early_init(), but then don't
switch to delay_tsc, with the result that delay_loop is used with
loops_per_jiffy set for delay_tsc.

Then in (late) tsc_init() lpj_fine is set (which is mostly unused) and
after which use_tsc_delay() is finally called.

Move both loops_per_jiffy and use_tsc_delay() into
tsc_enable_sched_clock() which is called the moment tsc_khz is
determined, be it early or late. Keeping the lot consistent.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220304152135.914397165@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Peter Zijlstra 2022-03-04 16:19:54 +01:00 committed by Greg Kroah-Hartman
parent 977b948140
commit 69f8aeab43
1 changed files with 3 additions and 3 deletions
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6
arch/x86/kernel/tsc.c
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@ -1487,6 +1487,9 @@ static unsigned long __init get_loops_per_jiffy(void)
static void __init tsc_enable_sched_clock(void)
{
loops_per_jiffy = get_loops_per_jiffy();
use_tsc_delay();
/* Sanitize TSC ADJUST before cyc2ns gets initialized */
tsc_store_and_check_tsc_adjust(true);
cyc2ns_init_boot_cpu();
@ -1502,8 +1505,6 @@ void __init tsc_early_init(void)
return;
if (!determine_cpu_tsc_frequencies(true))
return;
loops_per_jiffy = get_loops_per_jiffy();
tsc_enable_sched_clock();
}
@ -1537,7 +1538,6 @@ void __init tsc_init(void)
enable_sched_clock_irqtime();
lpj_fine = get_loops_per_jiffy();
use_tsc_delay();
check_system_tsc_reliable();