db13710a03
The various RCU Tasks flavors now do lazy grace periods when there are only asynchronous grace period requests. By default, the system will let 250 milliseconds elapse after the first call_rcu_tasks*() callbacki is queued before starting a grace period. In contrast, synchronous grace period requests such as synchronize_rcu_tasks*() will start a grace period immediately. However, invoking one of the call_rcu_tasks*() functions in a too-tight loop can result in a callback flood, which in turn can exhaust memory if grace periods are delayed for too long. This commit therefore sets a limit so that the grace-period kthread will be awakened when any CPU's callback list expands to contain rcupdate.rcu_task_lazy_lim callbacks elements (defaulting to 32, set to -1 to disable), the grace-period kthread will be awakened, thus cancelling any ongoing laziness and getting out in front of the potential callback flood. Cc: Alexei Starovoitov <ast@kernel.org> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> |
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.. | ||
Kconfig | ||
Kconfig.debug | ||
Makefile | ||
rcu_segcblist.c | ||
rcu_segcblist.h | ||
rcu.h | ||
rcuscale.c | ||
rcutorture.c | ||
refscale.c | ||
srcutiny.c | ||
srcutree.c | ||
sync.c | ||
tasks.h | ||
tiny.c | ||
tree_exp.h | ||
tree_nocb.h | ||
tree_plugin.h | ||
tree_stall.h | ||
tree.c | ||
tree.h | ||
update.c |