On (11/02/17 06:52), Tejun Heo wrote: > > When printk flushing isn't contended, whoever creates messages get to > flush them, which is great in both fairness and keeping log delivery > synchronous. However, when console drivers can't keep up with the > rate of new messages, which happens a lot, who ends up with the > flushing duty is determined by timing and everyone else's messages > become asynchronous.
Hello Tejun, thanks for the patch set. we are currently looking at another approach: lkml.kernel.org/r/[email protected] would you be interested in taking a look? there are some concerns, like a huge number of printk-s happening while console_sem is locked. e.g. console_lock()/console_unlock() on one of the CPUs, or console_lock(); printk(); ... printk(); console_unlock(); > > the problem of "the last printk()", which will take > over and do the flush. > > CPU0 CPU1 ~ CPU99 > console_lock(); > printk(); ... printk(); > console_unlock(); > IRQ on CPU2 > printk() > // take over console_sem > console_unlock() > -ss
