diff options
| author | Boqun Feng <boqun.feng@gmail.com> | 2018-06-15 21:06:31 +0200 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2018-07-12 21:36:06 +0200 |
| commit | fcc63543650150629c8a873cbef3578770acecd9 (patch) | |
| tree | 0f71000b6ba8565a16ed3fc1a6af23d0cdf470e4 /kernel/futex_compat.c | |
| parent | rcu: Make expedited grace period use direct call on last leaf (diff) | |
| download | linux-fcc63543650150629c8a873cbef3578770acecd9.tar.xz linux-fcc63543650150629c8a873cbef3578770acecd9.zip | |
rcu: Make expedited GPs handle CPU 0 being offline
Currently, the parallelized initialization of expedited grace periods uses
the workqueue associated with each rcu_node structure's ->grplo field.
This works fine unless that CPU is offline. This commit therefore uses
the CPU corresponding to the lowest-numbered online CPU, or just queues
the work on WORK_CPU_UNBOUND if there are no online CPUs corresponding
to this rcu_node structure.
Note that this patch uses cpu_is_offline() instead of the usual approach
of checking bits in the rcu_node structure's ->qsmaskinitnext field. This
is safe because preemption is disabled across both the cpu_is_offline()
check and the call to queue_work_on().
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
[ paulmck: Disable preemption to close offline race window. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Apply Peter Zijlstra feedback on CPU selection. ]
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/futex_compat.c')
0 files changed, 0 insertions, 0 deletions