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| author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2018-04-18 11:11:39 -0700 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2018-05-15 10:29:18 -0700 |
| commit | c91a8675b9cc697c725b6d97fcc7f157f4a989d0 (patch) | |
| tree | 335a7e265dda2c90ad19b8240b65be694fab0a0e /kernel/rcu/tree.h | |
| parent | 825a9911f6447299a69edacecc81fa2cdc5290a7 (diff) | |
| download | linux-stable-c91a8675b9cc697c725b6d97fcc7f157f4a989d0.tar.gz linux-stable-c91a8675b9cc697c725b6d97fcc7f157f4a989d0.tar.bz2 linux-stable-c91a8675b9cc697c725b6d97fcc7f157f4a989d0.zip | |
rcu: Add accessor macros for the ->need_future_gp[] array
Accessors for the ->need_future_gp[] array are currently open-coded,
which makes them difficult to change. To improve maintainability, this
commit adds need_future_gp_mask() to compute the indexing mask from the
array size, need_future_gp_element() to access the element corresponding
to the specified grace-period number, and need_any_future_gp() to
determine if any future grace period is needed. This commit also applies
need_future_gp_element() to existing open-coded single-element accesses.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
Diffstat (limited to 'kernel/rcu/tree.h')
| -rw-r--r-- | kernel/rcu/tree.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index f491ab4f2e8e..18b091474ffa 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -159,6 +159,21 @@ struct rcu_node { wait_queue_head_t exp_wq[4]; } ____cacheline_internodealigned_in_smp; +/* Accessors for ->need_future_gp[] array. */ +#define need_future_gp_mask() \ + (ARRAY_SIZE(((struct rcu_node *)NULL)->need_future_gp) - 1) +#define need_future_gp_element(rnp, c) \ + ((rnp)->need_future_gp[(c) & need_future_gp_mask()]) +#define need_any_future_gp(rnp) \ +({ \ + int __i; \ + bool __nonzero = false; \ + \ + for (__i = 0; __i < ARRAY_SIZE((rnp)->need_future_gp); __i++) \ + __nonzero = __nonzero || (rnp)->need_future_gp[__i]; \ + __nonzero; \ +}) + /* * Bitmasks in an rcu_node cover the interval [grplo, grphi] of CPU IDs, and * are indexed relative to this interval rather than the global CPU ID space. |