Change Details

1. Internal scheduling priorities: Always use symbolic ones without any hardcoded shift, to be agnostic to a change in semantics for a difference of priorities. Differences of less than 4 (RQ_PPQ) are insignificant and are simply removed. No functional change (intended). 2. zfs: spa: ZIO_TASKQ_ISSUE: Remove hardcoded shift, create a separate macro for its priority. 3. Finally switch to 256 distinct levels, by setting RQ_PPQ to 1 (builds upon previous changes). 4. Bump __FreeBSD_version. 5. Remove userland references to RQ_PPQ. 6. Restrict <sys/runq.h> to kernel usage.

Please see overview of project at D45393. 1. Internal scheduling priorities: Always use symbolic ones without any hardcoded shift, to be agnostic to a change in semantics for a difference of priorities. Differences of less than 4 (RQ_PPQ) are insignificant and are simply removed. No functional change (intended). 2. zfs: spa: ZIO_TASKQ_ISSUE: Remove hardcoded shift, create a separate macro for its priority. 3. Finally switch to 256 distinct levels, by setting RQ_PPQ to 1 (builds upon previous changes). 4. Bump __FreeBSD_version. 5. Remove userland references to RQ_PPQ. 6. Restrict <sys/runq.h> to kernel usage.

Please see overview of project at D45393. 1. Internal scheduling priorities: Always use symbolic ones without any hardcoded shift, to be agnostic to a change in semantics for a difference of priorities. Differences of less than 4 (RQ_PPQ) are insignificant and are simply removed. No functional change (intended). 2. zfs: spa: ZIO_TASKQ_ISSUE: Remove hardcoded shift, create a separate macro for its priority. 3. Finally switch to 256 distinct levels, by setting RQ_PPQ to 1 (builds upon previous changes). 4. Bump __FreeBSD_version. 5. Remove userland references to RQ_PPQ. 6. Restrict <sys/runq.h> to kernel usage.