7aa25fa5eb
This patch adds a set of priorities at the (numerically) lowest end of the range which have "meta-irq" behavior. Runnable threads at these priorities will always be scheduled before threads at lower priorities, EVEN IF those threads are otherwise cooperative and/or have taken a scheduler lock. Making such a thread runnable in any way thus has the effect of "interrupting" the current task and running the meta-irq thread synchronously, like an exception or system call. The intent is to use these priorities to implement "interrupt bottom half" or "tasklet" behavior, allowing driver subsystems to return from interrupt context but be guaranteed that user code will not be executed (on the current CPU) until the remaining work is finished. As this breaks the "promise" of non-preemptibility granted by the current API for cooperative threads, this tool probably shouldn't be used from application code. Signed-off-by: Andy Ross <andrew.j.ross@intel.com> |
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| .. | ||
| data_passing | ||
| memory | ||
| other | ||
| overview | ||
| synchronization | ||
| threads | ||
| timing | ||
| usermode | ||
| kernel.rst | ||