[PATCH 3/9] rcu: Rename jiffies_till_flush to jiffies_lazy_flush

From: Frederic Weisbecker
Date: Wed May 31 2023 - 06:18:14 EST


The variable name jiffies_till_flush is too generic and therefore:

* It may shadow a global variable
* It doesn't tell on what it operates

Make the name more precise, along with the related APIs.

Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx>
---
kernel/rcu/rcu.h | 8 ++++----
kernel/rcu/rcuscale.c | 6 +++---
kernel/rcu/tree_nocb.h | 20 ++++++++++----------
3 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index 98c1544cf572..236d6f837c49 100644
--- a/kernel/rcu/rcu.h
+++ b/kernel/rcu/rcu.h
@@ -526,11 +526,11 @@ enum rcutorture_type {
};

#if defined(CONFIG_RCU_LAZY)
-unsigned long rcu_lazy_get_jiffies_till_flush(void);
-void rcu_lazy_set_jiffies_till_flush(unsigned long j);
+unsigned long rcu_get_jiffies_lazy_flush(void);
+void rcu_set_jiffies_lazy_flush(unsigned long j);
#else
-static inline unsigned long rcu_lazy_get_jiffies_till_flush(void) { return 0; }
-static inline void rcu_lazy_set_jiffies_till_flush(unsigned long j) { }
+static inline unsigned long rcu_get_jiffies_lazy_flush(void) { return 0; }
+static inline void rcu_set_jiffies_lazy_flush(unsigned long j) { }
#endif

#if defined(CONFIG_TREE_RCU)
diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c
index 7fba3ab66e35..53ec80868791 100644
--- a/kernel/rcu/rcuscale.c
+++ b/kernel/rcu/rcuscale.c
@@ -725,9 +725,9 @@ kfree_scale_init(void)

if (kfree_by_call_rcu) {
/* do a test to check the timeout. */
- orig_jif = rcu_lazy_get_jiffies_till_flush();
+ orig_jif = rcu_get_jiffies_lazy_flush();

- rcu_lazy_set_jiffies_till_flush(2 * HZ);
+ rcu_set_jiffies_lazy_flush(2 * HZ);
rcu_barrier();

jif_start = jiffies;
@@ -736,7 +736,7 @@ kfree_scale_init(void)

smp_cond_load_relaxed(&rcu_lazy_test1_cb_called, VAL == 1);

- rcu_lazy_set_jiffies_till_flush(orig_jif);
+ rcu_set_jiffies_lazy_flush(orig_jif);

if (WARN_ON_ONCE(jiffies_at_lazy_cb - jif_start < 2 * HZ)) {
pr_alert("ERROR: call_rcu() CBs are not being lazy as expected!\n");
diff --git a/kernel/rcu/tree_nocb.h b/kernel/rcu/tree_nocb.h
index 43229d2b0c44..8320eb77b58b 100644
--- a/kernel/rcu/tree_nocb.h
+++ b/kernel/rcu/tree_nocb.h
@@ -264,21 +264,21 @@ static bool wake_nocb_gp(struct rcu_data *rdp, bool force)
* left unsubmitted to RCU after those many jiffies.
*/
#define LAZY_FLUSH_JIFFIES (10 * HZ)
-static unsigned long jiffies_till_flush = LAZY_FLUSH_JIFFIES;
+static unsigned long jiffies_lazy_flush = LAZY_FLUSH_JIFFIES;

#ifdef CONFIG_RCU_LAZY
// To be called only from test code.
-void rcu_lazy_set_jiffies_till_flush(unsigned long jif)
+void rcu_lazy_set_jiffies_lazy_flush(unsigned long jif)
{
- jiffies_till_flush = jif;
+ jiffies_lazy_flush = jif;
}
-EXPORT_SYMBOL(rcu_lazy_set_jiffies_till_flush);
+EXPORT_SYMBOL(rcu_lazy_set_jiffies_lazy_flush);

-unsigned long rcu_lazy_get_jiffies_till_flush(void)
+unsigned long rcu_lazy_get_jiffies_lazy_flush(void)
{
- return jiffies_till_flush;
+ return jiffies_lazy_flush;
}
-EXPORT_SYMBOL(rcu_lazy_get_jiffies_till_flush);
+EXPORT_SYMBOL(rcu_lazy_get_jiffies_lazy_flush);
#endif

/*
@@ -299,7 +299,7 @@ static void wake_nocb_gp_defer(struct rcu_data *rdp, int waketype,
*/
if (waketype == RCU_NOCB_WAKE_LAZY &&
rdp->nocb_defer_wakeup == RCU_NOCB_WAKE_NOT) {
- mod_timer(&rdp_gp->nocb_timer, jiffies + jiffies_till_flush);
+ mod_timer(&rdp_gp->nocb_timer, jiffies + jiffies_lazy_flush);
WRITE_ONCE(rdp_gp->nocb_defer_wakeup, waketype);
} else if (waketype == RCU_NOCB_WAKE_BYPASS) {
mod_timer(&rdp_gp->nocb_timer, jiffies + 2);
@@ -482,7 +482,7 @@ static bool rcu_nocb_try_bypass(struct rcu_data *rdp, struct rcu_head *rhp,
// flush ->nocb_bypass to ->cblist.
if ((ncbs && !bypass_is_lazy && j != READ_ONCE(rdp->nocb_bypass_first)) ||
(ncbs && bypass_is_lazy &&
- (time_after(j, READ_ONCE(rdp->nocb_bypass_first) + jiffies_till_flush))) ||
+ (time_after(j, READ_ONCE(rdp->nocb_bypass_first) + jiffies_lazy_flush))) ||
ncbs >= qhimark) {
rcu_nocb_lock(rdp);
*was_alldone = !rcu_segcblist_pend_cbs(&rdp->cblist);
@@ -723,7 +723,7 @@ static void nocb_gp_wait(struct rcu_data *my_rdp)
lazy_ncbs = READ_ONCE(rdp->lazy_len);

if (bypass_ncbs && (lazy_ncbs == bypass_ncbs) &&
- (time_after(j, READ_ONCE(rdp->nocb_bypass_first) + jiffies_till_flush) ||
+ (time_after(j, READ_ONCE(rdp->nocb_bypass_first) + jiffies_lazy_flush) ||
bypass_ncbs > 2 * qhimark)) {
flush_bypass = true;
} else if (bypass_ncbs && (lazy_ncbs != bypass_ncbs) &&
--
2.40.1