Which processor enhances jiffies in SMP?

As I read, jiffies are incremented by every ISR timer. But in SMP, all processors will have their own timer interrupt and, therefore, their own ISR timers. So my question is:

Is global to all jiffies processors? If so, how and which processor increases it in the ISR timer?

According to my understanding, jiffies cannot be per processor, otherwise the same process, when scheduled on different CPUs, will see a different jiffy value.

thank

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:
(LOC /proc/interrupts) CPU.
( 0) , CPU. jiffies.

, "Tickless Kernel" ( Linux 2.6.21, CONFIG_NO_HZ) . . , , Linux "" , , .

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. .

, tick_do_timer_cpu CPU, , jiffies. jiffies , , .

. kernel/time/tick-common.c

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