posix-timers: Add proper state tracking

Right now the state tracking is done by two struct members:

 - it_active:
     A boolean which tracks armed/disarmed state

 - it_signal_seq:
     A sequence counter which is used to invalidate settings
     and prevent rearming

Replace it_active with it_status and keep properly track about the states
in one place.

This allows to reuse it_signal_seq to track reprogramming, disarm and
delete operations in order to drop signals which are related to the state
previous of those operations.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/20241001083835.670337048@linutronix.de

1 files changed, 6 insertions, 0 deletions

diff --git a/kernel/time/posix-timers.h b/kernel/time/posix-timers.h
index 4784ea65f685..4d09677e584e 100644
--- a/kernel/time/posix-timers.h
+++ b/kernel/time/posix-timers.h
@@ -1,6 +1,12 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 #define TIMER_RETRY 1
 
+enum posix_timer_state {
+	POSIX_TIMER_DISARMED,
+	POSIX_TIMER_ARMED,
+	POSIX_TIMER_REQUEUE_PENDING,
+};
+
 struct k_clock {
 	int	(*clock_getres)(const clockid_t which_clock,
 				struct timespec64 *tp);