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authorPaul E. McKenney <paulmck@kernel.org>2024-10-16 09:19:29 -0700
committerFrederic Weisbecker <frederic@kernel.org>2024-10-23 18:00:17 +0200
commit26ff1fb02991e1260481185bb5ccab1ee498d5e4 (patch)
tree3a72625c5f0bb15dff4bdc1117f6b545dbda980a /kernel/rcu
parentf7345ccc62a4b880cf76458db5f320725f28e400 (diff)
rcu: Delete unused rcu_gp_might_be_stalled() function
The rcu_gp_might_be_stalled() function is no longer used, so this commit removes it. Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Diffstat (limited to 'kernel/rcu')
-rw-r--r--kernel/rcu/tree_stall.h30
1 files changed, 0 insertions, 30 deletions
diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h
index 4432db6d0b99..d7cdd535e50b 100644
--- a/kernel/rcu/tree_stall.h
+++ b/kernel/rcu/tree_stall.h
@@ -76,36 +76,6 @@ int rcu_jiffies_till_stall_check(void)
}
EXPORT_SYMBOL_GPL(rcu_jiffies_till_stall_check);
-/**
- * rcu_gp_might_be_stalled - Is it likely that the grace period is stalled?
- *
- * Returns @true if the current grace period is sufficiently old that
- * it is reasonable to assume that it might be stalled. This can be
- * useful when deciding whether to allocate memory to enable RCU-mediated
- * freeing on the one hand or just invoking synchronize_rcu() on the other.
- * The latter is preferable when the grace period is stalled.
- *
- * Note that sampling of the .gp_start and .gp_seq fields must be done
- * carefully to avoid false positives at the beginnings and ends of
- * grace periods.
- */
-bool rcu_gp_might_be_stalled(void)
-{
- unsigned long d = rcu_jiffies_till_stall_check() / RCU_STALL_MIGHT_DIV;
- unsigned long j = jiffies;
-
- if (d < RCU_STALL_MIGHT_MIN)
- d = RCU_STALL_MIGHT_MIN;
- smp_mb(); // jiffies before .gp_seq to avoid false positives.
- if (!rcu_gp_in_progress())
- return false;
- // Long delays at this point avoids false positive, but a delay
- // of ULONG_MAX/4 jiffies voids your no-false-positive warranty.
- smp_mb(); // .gp_seq before second .gp_start
- // And ditto here.
- return !time_before(j, READ_ONCE(rcu_state.gp_start) + d);
-}
-
/* Don't do RCU CPU stall warnings during long sysrq printouts. */
void rcu_sysrq_start(void)
{