Re: [patch 17/38] ext4: Replace get_cycles() usage with ktime_get()
"Arnd Bergmann" <[email protected]>
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On Fri, Apr 10, 2026, at 14:19, Thomas Gleixner wrote: > get_cycles() is not guaranteed to be functional on all systems/platforms > and the values returned are unitless and not easy to map to something > useful. > > Use ktime_get() instead, which provides nanosecond timestamps and is > functional everywhere. > > This is part of a larger effort to limit get_cycles() usage to low level > architecture code. > > Signed-off-by: Thomas Gleixner <[email protected]> > Cc: "Theodore Ts'o" <[email protected]> > Cc: [email protected] I think this is technically an ABI chance, since the time difference gets exported through procfs, but the new version is clearly the right thing to do since it replaces a hardware specific value with a portable one. Arnd