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Re: mutexes, IPL, tty locking

David Holland <> wrote:
>       if (oldspl == highest && cur->l_iplcounts[highest-1] == 0) {
>          while (highest > 0 && cur->l_iplcounts[highest-1] == 0) {
>             highest--;
>          }

It would probably be better to use bitmask and ffs() right here, to avoid
looping through priorities.   Anyway, this is some overhead in low level
primitive to support very rare cases.   I do not think it is worth.  Also,
the case in our TTY locking should be fixed be revamping it (i.e. having
locking in drivers).


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