commit 76ce7cfe35ef58f34e6ba85327afb5fbf6c3ff9b
author Pavel Tatashin <pasha.tatashin@oracle.com> Fri Oct 27 20:11:00 2017 -0400
committer Thomas Gleixner <tglx@linutronix.de> Tue Nov 07 16:04:54 2017 +0100
tree ad750f9e42d213b7847a9f3cec679cf4d9406951
parent e4880bc5dfb1f02b152e62a894b5c6f3e995b3cf

x86/smpboot: Make optimization of delay calibration work correctly

If the TSC has constant frequency then the delay calibration can be skipped
when it has been calibrated for a package already. This is checked in
calibrate_delay_is_known(), but that function is buggy in two aspects:

It returns 'false' if

  (!tsc_disabled && !cpu_has(&cpu_data(cpu), X86_FEATURE_CONSTANT_TSC)

which is obviously the reverse of the intended check and the check for the
sibling mask cannot work either because the topology links have not been
set up yet.

Correct the condition and move the call to set_cpu_sibling_map() before
invoking calibrate_delay() so the sibling check works correctly.

[ tglx: Rewrote changelong ]

Fixes: c25323c07345 ("x86/tsc: Use topology functions")
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: peterz@infradead.org
Cc: bob.picco@oracle.com
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20171028001100.26603-1-pasha.tatashin@oracle.com