[PATCH v2 27/37] hrtimer: Prepare handling of hard and softirq based hrtimers

Anna-Maria Gleixner
2017-10-22T21:46:09Z

[-- Attachment #1: hrtimer_Allow_function_reuse_for_softirq_based_hrtimer.patch --]
[-- Type: text/plain, Size: 3793 bytes --]

From: Anna-Maria Gleixner <anna-maria@linutronix.de>

The softirq based hrtimer can utilize most of the existing hrtimers
functions, but need to operate on a different data set.

Add an active_mask argument to various functions so the hard and soft bases
can be selected. Fixup the existing callers and hand in the ACTIVE_HARD
mask.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
---
kernel/time/hrtimer.c | 38 +++++++++++++++++++++++++++++---------
1 file changed, 29 insertions(+), 9 deletions(-)

--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -60,6 +60,15 @@
#include "tick-internal.h"

/*
+ * Masks for selecting the soft and hard context timers from
+ * cpu_base->active
+ */
+#define MASK_SHIFT (HRTIMER_BASE_MONOTONIC_SOFT)
+#define HRTIMER_ACTIVE_HARD ((1U << MASK_SHIFT) - 1)
+#define HRTIMER_ACTIVE_SOFT (HRTIMER_ACTIVE_HARD << MASK_SHIFT)
+#define HRTIMER_ACTIVE_ALL (HRTIMER_ACTIVE_SOFT | HRTIMER_ACTIVE_HARD)
+
+/*
* The timer bases:
*
* There are more clockids than hrtimer bases. Thus, we index
@@ -515,13 +524,24 @@ static ktime_t __hrtimer_next_event_base
return expires_next;
}

-static ktime_t __hrtimer_get_next_event(struct hrtimer_cpu_base *cpu_base)
+/*
+ * Recomputes cpu_base::*next_timer and returns the earliest expires_next but
+ * does not set cpu_base::*expires_next, that is done by hrtimer_reprogram.
+ *
+ * @active_mask must be one of:
+ * - HRTIMER_ACTIVE,
+ * - HRTIMER_ACTIVE_SOFT, or
+ * - HRTIMER_ACTIVE_HARD.
+ */
+static ktime_t __hrtimer_get_next_event(struct hrtimer_cpu_base *cpu_base,
+ unsigned int active_mask)
{
- unsigned int active = cpu_base->active_bases;
+ unsigned int active;
ktime_t expires_next = KTIME_MAX;

cpu_base->next_timer = NULL;

+ active = cpu_base->active_bases & active_mask;
expires_next = __hrtimer_next_event_base(cpu_base, active, expires_next);

return expires_next;
@@ -562,7 +582,7 @@ hrtimer_force_reprogram(struct hrtimer_c
{
ktime_t expires_next;

- expires_next = __hrtimer_get_next_event(cpu_base);
+ expires_next = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_HARD);

if (skip_equal && expires_next == cpu_base->expires_next)
return;
@@ -1086,7 +1106,7 @@ u64 hrtimer_get_next_event(void)
raw_spin_lock_irqsave(&cpu_base->lock, flags);

if (!__hrtimer_hres_active(cpu_base))
- expires = __hrtimer_get_next_event(cpu_base);
+ expires = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_HARD);

raw_spin_unlock_irqrestore(&cpu_base->lock, flags);

@@ -1260,10 +1280,10 @@ static void __run_hrtimer(struct hrtimer
}

static void __hrtimer_run_queues(struct hrtimer_cpu_base *cpu_base, ktime_t now,
- unsigned long flags)
+ unsigned long flags, unsigned int active_mask)
{
struct hrtimer_clock_base *base;
- unsigned int active = cpu_base->active_bases;
+ unsigned int active = cpu_base->active_bases & active_mask;

for_each_active_base(base, cpu_base, active) {
struct timerqueue_node *node;
@@ -1326,10 +1346,10 @@ void hrtimer_interrupt(struct clock_even
*/
cpu_base->expires_next = KTIME_MAX;

- __hrtimer_run_queues(cpu_base, now, flags);
+ __hrtimer_run_queues(cpu_base, now, flags, HRTIMER_ACTIVE_HARD);

/* Reevaluate the clock bases for the next expiry */
- expires_next = __hrtimer_get_next_event(cpu_base);
+ expires_next = __hrtimer_get_next_event(cpu_base, HRTIMER_ACTIVE_HARD);
/*
* Store the new expiry value so the migration code can verify
* against it.
@@ -1433,7 +1453,7 @@ void hrtimer_run_queues(void)

raw_spin_lock_irqsave(&cpu_base->lock, flags);
now = hrtimer_update_base(cpu_base);
- __hrtimer_run_queues(cpu_base, now, flags);
+ __hrtimer_run_queues(cpu_base, now, flags, HRTIMER_ACTIVE_HARD);
raw_spin_unlock_irqrestore(&cpu_base->lock, flags);
}