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x86/tsc: Prevent result truncation on 32bit
Loops per jiffy is calculated by multiplying tsc_khz with 1e3 and then dividing it by HZ. Both tsc_khz and the temporary variable holding the multiplication result are of type unsigned long, so on 32bit the result is truncated to the lower 32bit. Use u64 as type for the temporary variable and cast tsc_khz to it before multiplying. [ tglx: Massaged changelog and removed pointless braces ] Fixes: cf7a63e ("x86/tsc: Calibrate tsc only once") Signed-off-by: Chuanhua Lei <chuanhua.lei@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: yixin.zhu@linux.intel.com Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Tatashin <pasha.tatashin@microsoft.com> Cc: Rajvi Jingar <rajvi.jingar@intel.com> Cc: Dou Liyang <douly.fnst@cn.fujitsu.com> Link: https://lkml.kernel.org/r/1536228203-18701-1-git-send-email-chuanhua.lei@linux.intel.com
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