diff options
| author | Paul E. McKenney <paulmck@kernel.org> | 2022-11-22 13:53:57 -0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2022-11-29 15:00:06 -0800 |
| commit | 0cd7e350abc40eed5d3b60292dc102f700c88388 (patch) | |
| tree | f5777dc4fe1aed4fbbd1a38ba56b36d5af17dcfb /kernel/rcu/update.c | |
| parent | f733615e39aa2d6ddeef33b7b2c9aa6a5a2c2785 (diff) | |
rcu: Make SRCU mandatory
Kernels configured with CONFIG_PRINTK=n and CONFIG_SRCU=n get build
failures. This causes trouble for deep embedded systems. But given
that there are more than 25 instances of "select SRCU" in the kernel,
it is hard to believe that there are many kernels running in production
without SRCU. This commit therefore makes SRCU mandatory. The SRCU
Kconfig option remains for backwards compatibility, and will be removed
when it is no longer used.
[ paulmck: Update per kernel test robot feedback. ]
Reported-by: John Ogness <john.ogness@linutronix.de>
Reported-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: <linux-arch@vger.kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Diffstat (limited to 'kernel/rcu/update.c')
| -rw-r--r-- | kernel/rcu/update.c | 18 |
1 files changed, 7 insertions, 11 deletions
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index 738842c4886b..f5e6a2f95a2a 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -224,7 +224,7 @@ void rcu_test_sync_prims(void) synchronize_rcu_expedited(); } -#if !defined(CONFIG_TINY_RCU) || defined(CONFIG_SRCU) +#if !defined(CONFIG_TINY_RCU) /* * Switch to run-time mode once RCU has fully initialized. @@ -239,7 +239,7 @@ static int __init rcu_set_runtime_mode(void) } core_initcall(rcu_set_runtime_mode); -#endif /* #if !defined(CONFIG_TINY_RCU) || defined(CONFIG_SRCU) */ +#endif /* #if !defined(CONFIG_TINY_RCU) */ #ifdef CONFIG_DEBUG_LOCK_ALLOC static struct lock_class_key rcu_lock_key; @@ -559,10 +559,8 @@ static void early_boot_test_call_rcu(void) struct early_boot_kfree_rcu *rhp; call_rcu(&head, test_callback); - if (IS_ENABLED(CONFIG_SRCU)) { - early_srcu_cookie = start_poll_synchronize_srcu(&early_srcu); - call_srcu(&early_srcu, &shead, test_callback); - } + early_srcu_cookie = start_poll_synchronize_srcu(&early_srcu); + call_srcu(&early_srcu, &shead, test_callback); rhp = kmalloc(sizeof(*rhp), GFP_KERNEL); if (!WARN_ON_ONCE(!rhp)) kfree_rcu(rhp, rh); @@ -585,11 +583,9 @@ static int rcu_verify_early_boot_tests(void) if (rcu_self_test) { early_boot_test_counter++; rcu_barrier(); - if (IS_ENABLED(CONFIG_SRCU)) { - early_boot_test_counter++; - srcu_barrier(&early_srcu); - WARN_ON_ONCE(!poll_state_synchronize_srcu(&early_srcu, early_srcu_cookie)); - } + early_boot_test_counter++; + srcu_barrier(&early_srcu); + WARN_ON_ONCE(!poll_state_synchronize_srcu(&early_srcu, early_srcu_cookie)); } if (rcu_self_test_counter != early_boot_test_counter) { WARN_ON(1); |