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8107d8296b
CONFIG_PRINTK_TIME reveals that sched_clock has a wrong offset during boot: .. [ 0.000000] Movable zone: 0 pages used for memmap [ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 775679 [ 0.000000] Kernel command line: dasd=4b6c root=/dev/dasda1 ro noinitrd [ 0.000000] PID hash table entries: 4096 (order: 12, 32768 bytes) [6920575.975232] console [ttyS0] enabled [6920575.987586] Dentry cache hash table entries: 524288 (order: 10, 4194304 bytes) [6920575.991404] Inode-cache hash table entries: 262144 (order: 9, 2097152 bytes) .. The s390 implementation of sched_clock uses the store clock instruction and subtracts jiffies_timer_cc. jiffies_timer_cc is a local variable in arch/s390/kernel/time.c and only used for sched_clock and monotonic clock. For historical reasons there is an offset on that value. With todays code this offset is unnecessary. By removing that offset we can get a sched_clock which returns the nanoseconds after time_init. This improves CONFIG_PRINTK_TIME. Since sched_clock is the only user, I have also renamed jiffies_timer_cc to sched_clock_base_cc. In addition, the local variable init_timer_cc is redundant and can be romved as well. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>