1d082fd061
The rcu_preempt_note_context_switch() function is on a scheduling fast path, so it would be good to avoid disabling irqs. The reason that irqs are disabled is to synchronize process-level and irq-handler access to the task_struct ->rcu_read_unlock_special bitmask. This commit therefore makes ->rcu_read_unlock_special instead be a union of bools with a short allowing single-access checks in RCU's __rcu_read_unlock(). This results in the process-level and irq-handler accesses being simple loads and stores, so that irqs need no longer be disabled. This commit therefore removes the irq disabling from rcu_preempt_note_context_switch(). Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> |
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| .. | ||
| Makefile | ||
| rcu.h | ||
| rcutorture.c | ||
| srcu.c | ||
| tiny.c | ||
| tiny_plugin.h | ||
| tree.c | ||
| tree.h | ||
| tree_plugin.h | ||
| tree_trace.c | ||
| update.c | ||