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| author | Paul E. McKenney <paulmck@linux.ibm.com> | 2019-05-14 09:50:49 -0700 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.ibm.com> | 2019-08-13 14:35:49 -0700 |
| commit | e83e73f5b0f8de6a8978ba64185e80fdf48a2a63 (patch) | |
| tree | 2b866639f7c568562963466baa65ce4980821cb4 /kernel/rcu/tree.c | |
| parent | e6060b41c9955374079926a7612b857a8458ed1f (diff) | |
| download | linux-e83e73f5b0f8de6a8978ba64185e80fdf48a2a63.tar.bz2 | |
rcu/nocb: Leave ->cblist enabled for no-CBs CPUs
As a first step towards making no-CBs CPUs use the ->cblist, this commit
leaves the ->cblist enabled for these CPUs. The main reason to make
no-CBs CPUs use ->cblist is to take advantage of callback numbering,
which will reduce the effects of missed grace periods which in turn will
reduce forward-progress problems for no-CBs CPUs.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Diffstat (limited to 'kernel/rcu/tree.c')
| -rw-r--r-- | kernel/rcu/tree.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index f1a25d17e3a0..2917ce379b23 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2964,7 +2964,8 @@ rcu_boot_init_percpu_data(int cpu) * Initializes a CPU's per-CPU RCU data. Note that only one online or * offline event can be happening at a given time. Note also that we can * accept some slop in the rsp->gp_seq access due to the fact that this - * CPU cannot possibly have any RCU callbacks in flight yet. + * CPU cannot possibly have any non-offloaded RCU callbacks in flight yet. + * And any offloaded callbacks are being numbered elsewhere. */ int rcutree_prepare_cpu(unsigned int cpu) { @@ -2978,7 +2979,7 @@ int rcutree_prepare_cpu(unsigned int cpu) rdp->n_force_qs_snap = rcu_state.n_force_qs; rdp->blimit = blimit; if (rcu_segcblist_empty(&rdp->cblist) && /* No early-boot CBs? */ - !init_nocb_callback_list(rdp)) + !rcu_segcblist_is_offloaded(&rdp->cblist)) rcu_segcblist_init(&rdp->cblist); /* Re-enable callbacks. */ rdp->dynticks_nesting = 1; /* CPU not up, no tearing. */ rcu_dynticks_eqs_online(); |