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struct timekeeper is ordered suboptimal vs. cachelines. The layout, including the preceding seqcount (see struct tk_core in timekeeper.c) is: cacheline 0: seqcount, tkr_mono cacheline 1: tkr_raw, xtime_sec cacheline 2: ktime_sec ... tai_offset, internal variables cacheline 3: next_leap_ktime, raw_sec, internal variables cacheline 4: internal variables So any access to via ktime_get*() except for access to CLOCK_MONOTONIC_RAW will use either cachelines 0 + 1 or cachelines 0 + 2. Access to CLOCK_MONOTONIC_RAW uses cachelines 0 + 1 + 3. Reorder the members so that the result is more efficient: cacheline 0: seqcount, tkr_mono cacheline 1: xtime_sec, ktime_sec ... tai_offset cacheline 2: tkr_raw, raw_sec cacheline 3: internal variables cacheline 4: internal variables That means ktime_get*() will access cacheline 0 + 1 and CLOCK_MONOTONIC_RAW access will use cachelines 0 + 2. Update kernel-doc and fix formatting issues while at it. Also fix a typo in struct tk_read_base kernel-doc. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20241015100839.12702-1-anna-maria@linutronix.de