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authorLinus Torvalds <torvalds@linux-foundation.org>2016-12-12 19:56:15 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2016-12-12 19:56:15 -0800
commit9465d9cc31fa732089cd8bec9f1bdfcdc174a5ce (patch)
treefb31a0a6271b255ffe6e29b4f9eb4192253f8c7f /drivers/base
parente71c3978d6f97659f6c3ee942c3e581299e4adf2 (diff)
parentc029a2bec66e42e57538cb65e28618baf6a4b311 (diff)
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner: "The time/timekeeping/timer folks deliver with this update: - Fix a reintroduced signed/unsigned issue and cleanup the whole signed/unsigned mess in the timekeeping core so this wont happen accidentaly again. - Add a new trace clock based on boot time - Prevent injection of random sleep times when PM tracing abuses the RTC for storage - Make posix timers configurable for real tiny systems - Add tracepoints for the alarm timer subsystem so timer based suspend wakeups can be instrumented - The usual pile of fixes and updates to core and drivers" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) timekeeping: Use mul_u64_u32_shr() instead of open coding it timekeeping: Get rid of pointless typecasts timekeeping: Make the conversion call chain consistently unsigned timekeeping_Force_unsigned_clocksource_to_nanoseconds_conversion alarmtimer: Add tracepoints for alarm timers trace: Update documentation for mono, mono_raw and boot clock trace: Add an option for boot clock as trace clock timekeeping: Add a fast and NMI safe boot clock timekeeping/clocksource_cyc2ns: Document intended range limitation timekeeping: Ignore the bogus sleep time if pm_trace is enabled selftests/timers: Fix spelling mistake "Asyncrhonous" -> "Asynchronous" clocksource/drivers/bcm2835_timer: Unmap region obtained by of_iomap clocksource/drivers/arm_arch_timer: Map frame with of_io_request_and_map() arm64: dts: rockchip: Arch counter doesn't tick in system suspend clocksource/drivers/arm_arch_timer: Don't assume clock runs in suspend posix-timers: Make them configurable posix_cpu_timers: Move the add_device_randomness() call to a proper place timer: Move sys_alarm from timer.c to itimer.c ptp_clock: Allow for it to be optional Kconfig: Regenerate *.c_shipped files after previous changes ...
Diffstat (limited to 'drivers/base')
-rw-r--r--drivers/base/power/trace.c27
1 files changed, 27 insertions, 0 deletions
diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c
index efec10b49d59..1cda505d6a85 100644
--- a/drivers/base/power/trace.c
+++ b/drivers/base/power/trace.c
@@ -10,6 +10,7 @@
#include <linux/pm-trace.h>
#include <linux/export.h>
#include <linux/rtc.h>
+#include <linux/suspend.h>
#include <linux/mc146818rtc.h>
@@ -74,6 +75,9 @@
#define DEVSEED (7919)
+bool pm_trace_rtc_abused __read_mostly;
+EXPORT_SYMBOL_GPL(pm_trace_rtc_abused);
+
static unsigned int dev_hash_value;
static int set_magic_time(unsigned int user, unsigned int file, unsigned int device)
@@ -104,6 +108,7 @@ static int set_magic_time(unsigned int user, unsigned int file, unsigned int dev
time.tm_min = (n % 20) * 3;
n /= 20;
mc146818_set_time(&time);
+ pm_trace_rtc_abused = true;
return n ? -1 : 0;
}
@@ -239,9 +244,31 @@ int show_trace_dev_match(char *buf, size_t size)
return ret;
}
+static int
+pm_trace_notify(struct notifier_block *nb, unsigned long mode, void *_unused)
+{
+ switch (mode) {
+ case PM_POST_HIBERNATION:
+ case PM_POST_SUSPEND:
+ if (pm_trace_rtc_abused) {
+ pm_trace_rtc_abused = false;
+ pr_warn("Possible incorrect RTC due to pm_trace, please use 'ntpdate' or 'rdate' to reset it.\n");
+ }
+ break;
+ default:
+ break;
+ }
+ return 0;
+}
+
+static struct notifier_block pm_trace_nb = {
+ .notifier_call = pm_trace_notify,
+};
+
static int early_resume_init(void)
{
hash_value_early_read = read_magic_time();
+ register_pm_notifier(&pm_trace_nb);
return 0;
}