22607d66bb
On small systems, in the absence of readers, expedited SRCU grace periods can complete in less than a microsecond. This means that an eight-CPU system can have all CPUs doing synchronize_srcu() in a tight loop and almost always expedite. This might actually be desirable in some situations, but in general it is a good way to needlessly burn CPU cycles. And in those situations where it is desirable, your friend is the function synchronize_srcu_expedited(). For other situations, this commit adds a kernel parameter that specifies a holdoff between completing the last SRCU grace period and auto-expediting the next. If the next grace period starts before the holdoff expires, auto-expediting is disabled. The holdoff is 50 microseconds by default, and can be tuned to the desired number of nanoseconds. A value of zero disables auto-expediting. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Mike Galbraith <efault@gmx.de> |
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| .. | ||
| Makefile | ||
| rcu.h | ||
| rcuperf.c | ||
| rcutorture.c | ||
| srcu.c | ||
| srcutiny.c | ||
| srcutree.c | ||
| sync.c | ||
| tiny.c | ||
| tiny_plugin.h | ||
| tree.c | ||
| tree.h | ||
| tree_exp.h | ||
| tree_plugin.h | ||
| tree_trace.c | ||
| update.c | ||