Messages in this thread | | | Subject | Re: printk meeting at LPC | From | Tetsuo Handa <> | Date | Mon, 16 Sep 2019 13:30:17 +0900 |
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On 2019/09/13 22:26, John Ogness wrote: > 6. A new may-sleep function pr_flush() will be made available to wait > for all previously printk'd messages to be output on all consoles before > proceeding. For example: > > pr_cont("Running test ABC... "); > pr_flush(); > > do_test(); > > pr_cont("PASSED\n"); > pr_flush();
Don't we need to allow printk() callers to know the sequence number which the printk() has queued? Something like
u64 seq; pr_info(...); pr_info(...); pr_info(...); seq = pr_current_seq(); pr_wait_seq(seq);
in case concurrently executed printk() flooding keeps adding a lot of pending output?
By the way, do we need to keep printk() return bytes like printf() ? Maybe we can make printk() return "void", for almost nobody can do meaningful things with the return value.
> 9. Support for printk dictionaries will be discontinued. I will look > into who is using this and why. If printk dictionaries are important for > you, speak up now!
I think that dev_printk() is using "const char *dict, size_t dictlen," part via create_syslog_header(). Some userspace programs might depend on availability of such information.
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