Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
posix-timers: Move sequence logic into struct k_itimer
The posix timer signal handling uses siginfo::si_sys_private for handling
the sequence counter check. That indirection is not longer required and the
sequence count value at signal queueing time can be stored in struct
k_itimer itself.
This removes the requirement of treating siginfo::si_sys_private special as
it's now always zero as the kernel does not touch it anymore.
Suggested-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Link: https://lore.kernel.org/all/20241105064213.852619866@linutronix.de
+7
-10
+2
include/linux/posix-timers.h
+2
include/linux/posix-timers.h
···
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* @it_overrun: The overrun counter for pending signals
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* @it_overrun_last: The overrun at the time of the last delivered signal
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* @it_signal_seq: Sequence count to control signal delivery
165
+
* @it_sigqueue_seq: The sequence count at the point where the signal was queued
165
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* @it_sigev_notify: The notify word of sigevent struct for signal delivery
166
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* @it_interval: The interval for periodic timers
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* @it_signal: Pointer to the creators signal struct
···
185
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s64 it_overrun;
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s64 it_overrun_last;
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unsigned int it_signal_seq;
187
+
unsigned int it_sigqueue_seq;
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int it_sigev_notify;
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enum pid_type it_pid_type;
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ktime_t it_interval;
+1
-1
include/uapi/asm-generic/siginfo.h
+1
-1
include/uapi/asm-generic/siginfo.h
···
46
46
__kernel_timer_t _tid; /* timer id */
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47
int _overrun; /* overrun count */
48
48
sigval_t _sigval; /* same as below */
49
-
int _sys_private; /* not to be passed to user */
49
+
int _sys_private; /* Not used by the kernel. Historic leftover. Always 0. */
50
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} _timer;
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51
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52
/* POSIX.1b signals */
+3
-5
kernel/signal.c
+3
-5
kernel/signal.c
···
1976
1976
return -1;
1977
1977
1978
1978
/*
1979
-
* Update @q::info::si_sys_private for posix timer signals with
1980
-
* sighand locked to prevent a race against dequeue_signal() which
1981
-
* decides based on si_sys_private whether to invoke
1982
-
* posixtimer_rearm() or not.
1979
+
* Update @tmr::sigqueue_seq for posix timer signals with sighand
1980
+
* locked to prevent a race against dequeue_signal().
1983
1981
*/
1984
-
q->info.si_sys_private = tmr->it_signal_seq;
1982
+
tmr->it_sigqueue_seq = tmr->it_signal_seq;
1985
1983
1986
1984
ret = 1; /* the signal is ignored */
1987
1985
if (!prepare_signal(sig, t, false)) {
+1
-4
kernel/time/posix-timers.c
+1
-4
kernel/time/posix-timers.c
···
259
259
* since the signal was queued. In either case, don't rearm and
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* drop the signal.
261
261
*/
262
-
if (timr->it_signal_seq != info->si_sys_private || WARN_ON_ONCE(!timr->it_signal))
262
+
if (timr->it_signal_seq != timr->it_sigqueue_seq || WARN_ON_ONCE(!timr->it_signal))
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return false;
264
264
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if (!timr->it_interval || WARN_ON_ONCE(timr->it_status != POSIX_TIMER_REQUEUE_PENDING))
···
297
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posixtimer_putref(timr);
298
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spin_lock(¤t->sighand->siglock);
300
-
301
-
/* Don't expose the si_sys_private value to userspace */
302
-
info->si_sys_private = 0;
303
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return ret;
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301
}
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