On 05/29/2015 09:47 AM, Len Brown wrote:
However, a clear pattern jumped out of the trace for how long
the BSP waits for the AP to set itself in cpu_callin_mask.
This is the time in start secondary where cpu_init() is running,
up through smp_callin() is called.
On the 1st package, each remote AP take 9 delays = 900 us to do this,
whether they are new cores or HT siblings of cores already up.
But the 1st processor on remote_packages_ aka nodes, takes 60,000 us
No typo -- that is 60ms!
That does sound like calibrate_delay(), which "waits" for 5 * (10ms + 1 tick)
on each newly encountered package...
Regards
Jan
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
