Re: Does Printk() block another CPU in dual cpu platforms?

[Fawad Lateef]

On 11/9/05, John Smith <multisyncfe991@xxxxxxxxxxx> wrote:
>
> I just have a question about the usage of printk in multi-processor
> platforms. If the program on two CPUs both try to call printk to output
> something, will the program running on one CPUs get blocked (or just
> spinning there) till the other is done with printk()?
>

I think yes, but for a very less time as printk holds the spin_lock to
logbuf_lock which will make to wait the printk on other CPU, and then
printk just copies the content to log_buffer and then call
release_console_sem which actually send the data to console later !

--
Fawad Lateef
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