From 244b2c5ca8b14627e4a17755e5922221e121c771 Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Wed, 09 Oct 2024 06:15:07 +0000
Subject: [PATCH] change system file
---
kernel/kernel/time/alarmtimer.c | 175 +++++++++++++++++++++++++++++++++++++++-------------------
1 files changed, 117 insertions(+), 58 deletions(-)
diff --git a/kernel/kernel/time/alarmtimer.c b/kernel/kernel/time/alarmtimer.c
index 9810862..3a20a9f 100644
--- a/kernel/kernel/time/alarmtimer.c
+++ b/kernel/kernel/time/alarmtimer.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* Alarmtimer interface
*
@@ -10,10 +11,6 @@
* Copyright (C) 2010 IBM Corperation
*
* Author: John Stultz <john.stultz@linaro.org>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
*/
#include <linux/time.h>
#include <linux/hrtimer.h>
@@ -29,23 +26,28 @@
#include <linux/freezer.h>
#include <linux/compat.h>
#include <linux/module.h>
+#include <linux/time_namespace.h>
#include "posix-timers.h"
#define CREATE_TRACE_POINTS
#include <trace/events/alarmtimer.h>
+#undef CREATE_TRACE_POINTS
+#include <trace/hooks/wakeupbypass.h>
/**
* struct alarm_base - Alarm timer bases
* @lock: Lock for syncrhonized access to the base
* @timerqueue: Timerqueue head managing the list of events
- * @gettime: Function to read the time correlating to the base
+ * @get_ktime: Function to read the time correlating to the base
+ * @get_timespec: Function to read the namespace time correlating to the base
* @base_clockid: clockid for the base
*/
static struct alarm_base {
spinlock_t lock;
struct timerqueue_head timerqueue;
- ktime_t (*gettime)(void);
+ ktime_t (*get_ktime)(void);
+ void (*get_timespec)(struct timespec64 *tp);
clockid_t base_clockid;
} alarm_bases[ALARM_NUMTYPE];
@@ -58,8 +60,6 @@
#endif
#ifdef CONFIG_RTC_CLASS
-static struct wakeup_source *ws;
-
/* rtc timer and device for setting alarm wakeups at suspend */
static struct rtc_timer rtctimer;
static struct rtc_device *rtcdev;
@@ -69,8 +69,6 @@
* alarmtimer_get_rtcdev - Return selected rtcdevice
*
* This function returns the rtc device to use for wakealarms.
- * If one has not already been chosen, it checks to see if a
- * functional rtc device is available.
*/
struct rtc_device *alarmtimer_get_rtcdev(void)
{
@@ -90,7 +88,7 @@
{
unsigned long flags;
struct rtc_device *rtc = to_rtc_device(dev);
- struct wakeup_source *__ws;
+ struct platform_device *pdev;
int ret = 0;
if (rtcdev)
@@ -101,10 +99,13 @@
if (!device_may_wakeup(rtc->dev.parent))
return -1;
- __ws = wakeup_source_register(dev, "alarmtimer");
+ pdev = platform_device_register_data(dev, "alarmtimer",
+ PLATFORM_DEVID_AUTO, NULL, 0);
+ if (!IS_ERR(pdev))
+ device_init_wakeup(&pdev->dev, true);
spin_lock_irqsave(&rtcdev_lock, flags);
- if (!rtcdev) {
+ if (!IS_ERR(pdev) && !rtcdev) {
if (!try_module_get(rtc->owner)) {
ret = -1;
goto unlock;
@@ -113,13 +114,14 @@
rtcdev = rtc;
/* hold a reference so it doesn't go away */
get_device(dev);
- ws = __ws;
- __ws = NULL;
+ pdev = NULL;
+ } else {
+ ret = -1;
}
unlock:
spin_unlock_irqrestore(&rtcdev_lock, flags);
- wakeup_source_unregister(__ws);
+ platform_device_unregister(pdev);
return ret;
}
@@ -143,11 +145,6 @@
class_interface_unregister(&alarmtimer_rtc_interface);
}
#else
-struct rtc_device *alarmtimer_get_rtcdev(void)
-{
- return NULL;
-}
-#define rtcdev (NULL)
static inline int alarmtimer_rtc_interface_setup(void) { return 0; }
static inline void alarmtimer_rtc_interface_remove(void) { }
static inline void alarmtimer_rtc_timer_init(void) { }
@@ -197,7 +194,7 @@
* When a alarm timer fires, this runs through the timerqueue to
* see which alarms expired, and runs those. If there are more alarm
* timers queued for the future, we set the hrtimer to fire when
- * when the next future alarm timer expires.
+ * the next future alarm timer expires.
*/
static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
{
@@ -212,7 +209,7 @@
spin_unlock_irqrestore(&base->lock, flags);
if (alarm->function)
- restart = alarm->function(alarm, base->gettime());
+ restart = alarm->function(alarm, base->get_ktime());
spin_lock_irqsave(&base->lock, flags);
if (restart != ALARMTIMER_NORESTART) {
@@ -222,7 +219,7 @@
}
spin_unlock_irqrestore(&base->lock, flags);
- trace_alarmtimer_fired(alarm, base->gettime());
+ trace_alarmtimer_fired(alarm, base->get_ktime());
return ret;
}
@@ -230,7 +227,7 @@
ktime_t alarm_expires_remaining(const struct alarm *alarm)
{
struct alarm_base *base = &alarm_bases[alarm->type];
- return ktime_sub(alarm->node.expires, base->gettime());
+ return ktime_sub(alarm->node.expires, base->get_ktime());
}
EXPORT_SYMBOL_GPL(alarm_expires_remaining);
@@ -238,7 +235,6 @@
/**
* alarmtimer_suspend - Suspend time callback
* @dev: unused
- * @state: unused
*
* When we are going into suspend, we look through the bases
* to see which is the soonest timer to expire. We then
@@ -252,6 +248,7 @@
struct rtc_device *rtc;
unsigned long flags;
struct rtc_time tm;
+ int wakeup_bypass_enabled = 0;
spin_lock_irqsave(&freezer_delta_lock, flags);
min = freezer_delta;
@@ -259,6 +256,10 @@
type = freezer_alarmtype;
freezer_delta = 0;
spin_unlock_irqrestore(&freezer_delta_lock, flags);
+
+ trace_android_vh_wakeup_bypass(&wakeup_bypass_enabled);
+ if (wakeup_bypass_enabled)
+ return 0;
rtc = alarmtimer_get_rtcdev();
/* If we have no rtcdev, just return */
@@ -276,7 +277,7 @@
spin_unlock_irqrestore(&base->lock, flags);
if (!next)
continue;
- delta = ktime_sub(next->expires, base->gettime());
+ delta = ktime_sub(next->expires, base->get_ktime());
if (!min || (delta < min)) {
expires = next->expires;
min = delta;
@@ -287,7 +288,7 @@
return 0;
if (ktime_to_ns(min) < 2 * NSEC_PER_SEC) {
- __pm_wakeup_event(ws, 2 * MSEC_PER_SEC);
+ pm_wakeup_event(dev, 2 * MSEC_PER_SEC);
return -EBUSY;
}
@@ -302,7 +303,7 @@
/* Set alarm, if in the past reject suspend briefly to handle */
ret = rtc_timer_start(rtc, &rtctimer, now, 0);
if (ret < 0)
- __pm_wakeup_event(ws, MSEC_PER_SEC);
+ pm_wakeup_event(dev, MSEC_PER_SEC);
return ret;
}
@@ -370,7 +371,7 @@
hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS);
spin_unlock_irqrestore(&base->lock, flags);
- trace_alarmtimer_start(alarm, base->gettime());
+ trace_alarmtimer_start(alarm, base->get_ktime());
}
EXPORT_SYMBOL_GPL(alarm_start);
@@ -383,7 +384,7 @@
{
struct alarm_base *base = &alarm_bases[alarm->type];
- start = ktime_add_safe(start, base->gettime());
+ start = ktime_add_safe(start, base->get_ktime());
alarm_start(alarm, start);
}
EXPORT_SYMBOL_GPL(alarm_start_relative);
@@ -420,7 +421,7 @@
alarmtimer_dequeue(base, alarm);
spin_unlock_irqrestore(&base->lock, flags);
- trace_alarmtimer_cancel(alarm, base->gettime());
+ trace_alarmtimer_cancel(alarm, base->get_ktime());
return ret;
}
EXPORT_SYMBOL_GPL(alarm_try_to_cancel);
@@ -438,7 +439,7 @@
int ret = alarm_try_to_cancel(alarm);
if (ret >= 0)
return ret;
- hrtimer_grab_expiry_lock(&alarm->timer);
+ hrtimer_cancel_wait_running(&alarm->timer);
}
}
EXPORT_SYMBOL_GPL(alarm_cancel);
@@ -476,11 +477,35 @@
}
EXPORT_SYMBOL_GPL(alarm_forward);
-u64 alarm_forward_now(struct alarm *alarm, ktime_t interval)
+static u64 __alarm_forward_now(struct alarm *alarm, ktime_t interval, bool throttle)
{
struct alarm_base *base = &alarm_bases[alarm->type];
+ ktime_t now = base->get_ktime();
- return alarm_forward(alarm, base->gettime(), interval);
+ if (IS_ENABLED(CONFIG_HIGH_RES_TIMERS) && throttle) {
+ /*
+ * Same issue as with posix_timer_fn(). Timers which are
+ * periodic but the signal is ignored can starve the system
+ * with a very small interval. The real fix which was
+ * promised in the context of posix_timer_fn() never
+ * materialized, but someone should really work on it.
+ *
+ * To prevent DOS fake @now to be 1 jiffie out which keeps
+ * the overrun accounting correct but creates an
+ * inconsistency vs. timer_gettime(2).
+ */
+ ktime_t kj = NSEC_PER_SEC / HZ;
+
+ if (interval < kj)
+ now = ktime_add(now, kj);
+ }
+
+ return alarm_forward(alarm, now, interval);
+}
+
+u64 alarm_forward_now(struct alarm *alarm, ktime_t interval)
+{
+ return __alarm_forward_now(alarm, interval, false);
}
EXPORT_SYMBOL_GPL(alarm_forward_now);
@@ -506,7 +531,7 @@
return;
}
- delta = ktime_sub(absexp, base->gettime());
+ delta = ktime_sub(absexp, base->get_ktime());
spin_lock_irqsave(&freezer_delta_lock, flags);
if (!freezer_delta || (delta < freezer_delta)) {
@@ -554,9 +579,10 @@
if (posix_timer_event(ptr, si_private) && ptr->it_interval) {
/*
* Handle ignored signals and rearm the timer. This will go
- * away once we handle ignored signals proper.
+ * away once we handle ignored signals proper. Ensure that
+ * small intervals cannot starve the system.
*/
- ptr->it_overrun += alarm_forward_now(alarm, ptr->it_interval);
+ ptr->it_overrun += __alarm_forward_now(alarm, ptr->it_interval, true);
++ptr->it_requeue_pending;
ptr->it_active = 1;
result = ALARMTIMER_RESTART;
@@ -612,6 +638,19 @@
}
/**
+ * alarm_timer_wait_running - Posix timer callback to wait for a timer
+ * @timr: Pointer to the posixtimer data struct
+ *
+ * Called from the core code when timer cancel detected that the callback
+ * is running. @timr is unlocked and rcu read lock is held to prevent it
+ * from being freed.
+ */
+static void alarm_timer_wait_running(struct k_itimer *timr)
+{
+ hrtimer_cancel_wait_running(&timr->it.alarm.alarmtimer.timer);
+}
+
+/**
* alarm_timer_arm - Posix timer callback to arm a timer
* @timr: Pointer to the posixtimer data struct
* @expires: The new expiry time
@@ -625,7 +664,7 @@
struct alarm_base *base = &alarm_bases[alarm->type];
if (!absolute)
- expires = ktime_add_safe(expires, base->gettime());
+ expires = ktime_add_safe(expires, base->get_ktime());
if (sigev_none)
alarm->node.expires = expires;
else
@@ -650,21 +689,38 @@
}
/**
- * alarm_clock_get - posix clock_get interface
+ * alarm_clock_get_timespec - posix clock_get_timespec interface
* @which_clock: clockid
* @tp: timespec to fill.
*
- * Provides the underlying alarm base time.
+ * Provides the underlying alarm base time in a tasks time namespace.
*/
-static int alarm_clock_get(clockid_t which_clock, struct timespec64 *tp)
+static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp)
{
struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)];
if (!alarmtimer_get_rtcdev())
return -EINVAL;
- *tp = ktime_to_timespec64(base->gettime());
+ base->get_timespec(tp);
+
return 0;
+}
+
+/**
+ * alarm_clock_get_ktime - posix clock_get_ktime interface
+ * @which_clock: clockid
+ *
+ * Provides the underlying alarm base time in the root namespace.
+ */
+static ktime_t alarm_clock_get_ktime(clockid_t which_clock)
+{
+ struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)];
+
+ if (!alarmtimer_get_rtcdev())
+ return -EINVAL;
+
+ return base->get_ktime();
}
/**
@@ -740,7 +796,7 @@
struct timespec64 rmt;
ktime_t rem;
- rem = ktime_sub(absexp, alarm_bases[type].gettime());
+ rem = ktime_sub(absexp, alarm_bases[type].get_ktime());
if (rem <= 0)
return 0;
@@ -809,9 +865,11 @@
exp = timespec64_to_ktime(*tsreq);
/* Convert (if necessary) to absolute time */
if (flags != TIMER_ABSTIME) {
- ktime_t now = alarm_bases[type].gettime();
+ ktime_t now = alarm_bases[type].get_ktime();
exp = ktime_add_safe(now, exp);
+ } else {
+ exp = timens_ktime_to_host(which_clock, exp);
}
ret = alarmtimer_do_nsleep(&alarm, exp, type);
@@ -830,7 +888,8 @@
const struct k_clock alarm_clock = {
.clock_getres = alarm_clock_getres,
- .clock_get = alarm_clock_get,
+ .clock_get_ktime = alarm_clock_get_ktime,
+ .clock_get_timespec = alarm_clock_get_timespec,
.timer_create = alarm_timer_create,
.timer_set = common_timer_set,
.timer_del = common_timer_del,
@@ -840,6 +899,7 @@
.timer_forward = alarm_timer_forward,
.timer_remaining = alarm_timer_remaining,
.timer_try_to_cancel = alarm_timer_try_to_cancel,
+ .timer_wait_running = alarm_timer_wait_running,
.nsleep = alarm_timer_nsleep,
};
#endif /* CONFIG_POSIX_TIMERS */
@@ -858,6 +918,12 @@
}
};
+static void get_boottime_timespec(struct timespec64 *tp)
+{
+ ktime_get_boottime_ts64(tp);
+ timens_add_boottime(tp);
+}
+
/**
* alarmtimer_init - Initialize alarm timer code
*
@@ -866,17 +932,18 @@
*/
static int __init alarmtimer_init(void)
{
- struct platform_device *pdev;
- int error = 0;
+ int error;
int i;
alarmtimer_rtc_timer_init();
/* Initialize alarm bases */
alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME;
- alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real;
+ alarm_bases[ALARM_REALTIME].get_ktime = &ktime_get_real;
+ alarm_bases[ALARM_REALTIME].get_timespec = ktime_get_real_ts64;
alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME;
- alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime;
+ alarm_bases[ALARM_BOOTTIME].get_ktime = &ktime_get_boottime;
+ alarm_bases[ALARM_BOOTTIME].get_timespec = get_boottime_timespec;
for (i = 0; i < ALARM_NUMTYPE; i++) {
timerqueue_init_head(&alarm_bases[i].timerqueue);
spin_lock_init(&alarm_bases[i].lock);
@@ -890,15 +957,7 @@
if (error)
goto out_if;
- pdev = platform_device_register_simple("alarmtimer", -1, NULL, 0);
- if (IS_ERR(pdev)) {
- error = PTR_ERR(pdev);
- goto out_drv;
- }
return 0;
-
-out_drv:
- platform_driver_unregister(&alarmtimer_driver);
out_if:
alarmtimer_rtc_interface_remove();
return error;
--
Gitblit v1.6.2