locking in a device driver

Dinesh Nair dinesh at alphaque.com
Wed Nov 2 11:02:06 PST 2005



On 10/28/05 10:52 M. Warner Losh said the following:
> libc_r will block all other threads in the application while an ioctl
> executes.  libpthread and libthr won't.  I've had several bugs at work

so if the userland thread does an ioctl, and the the driver goes to 
tsleep() when the ioctl is received, all other threads are also blocked 
from executing, i.e wont be context switched to run ?

is this behaviour only 4.x specific or is it also there in 5.x ?

-- 
Regards,                           /\_/\   "All dogs go to heaven."
dinesh at alphaque.com                (0 0)    http://www.alphaque.com/
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