From nobody Sun Nov 24 16:44:13 2024 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 80BA6200CAE for ; Tue, 5 Nov 2024 08:14:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730794492; cv=none; b=QR6CtKmRD+lVZz8DEkeEH7sitFS/z/ChnbsQPBW77jmsBZJWW2nDlNvZzLMe08dwB7CZUnxeSQKbTN0Hy/E9dCJPzL8aOytC7VIUD1tJHwS2CHX/8MVd2vYogW6i/YuzGqBDfvZ4j57b/rHrt7EvjIiln2H/ZuzGrzt5oleP7dY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730794492; c=relaxed/simple; bh=ubluM7VL7U4qZdDlhPmrWete8fA4Qc5SDItcL0E4eTI=; h=Message-ID:From:To:Cc:Subject:References:MIME-Version: Content-Type:Date; b=fTWZvShFW/DLSMJN5ru/iD3BKW/50oCzFdIJBz1kwenThk9Sk1wbBdAU8oAqigqpoz2tywsZi8zARLk4HiJyOfBAnrx5Xdc7uttpEpff1iMbq8cfciEd3ny/eTI21S6BVaFj9bWecMwJaTgvpdd5KAmW8wpDkZNj/H0YBjMjG8c= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=3SXfJAb2; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=kNhOFKRh; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="3SXfJAb2"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="kNhOFKRh" Message-ID: <20241105064213.852619866@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1730794489; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=o1ks1lD5Wsww0i59mhgG4iV/2G0j+TRp1u5nKEoD0lo=; b=3SXfJAb2u2wA/ZghIHFj+eFHrLvqbZscneXlUY+eFBfmsCRbWay1TMEwyAwYYwQx/BjUfO FGcF2SIK63GtV9vwIr3fx0Ls/RUxbSWIY1VyiGR+Grn6FMrS0zYwgGMLhuq2BrYhB7I2O/ b+OO09Yh0NxEoUPmt8F9eBnEzUcgoiSMt9t1YUdRPBsEmjl/Q8QN51LXtjippcfAMErLL2 JvSHuQ9Mib+NT/86U4tbBXsub4Stk+bxdxF1rrG3xUMkOZcd6HrfhwyWvwe6AC7RB/a1sR gl6tLWxEErNu5TCaenHlILmwTnECS9Z7hCOw+4OfBbdGiRlIKO9iKEbTl+Ajqw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1730794489; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=o1ks1lD5Wsww0i59mhgG4iV/2G0j+TRp1u5nKEoD0lo=; b=kNhOFKRh4BEeksGs4tG79Gy2fXsiqX0n6dUxk6etjaUkM5p6qWHotnv7PM4wZtoyy3d6j9 b0xLVL0XhuvAXdDw== From: Thomas Gleixner To: LKML Cc: Anna-Maria Behnsen , Frederic Weisbecker , John Stultz , Peter Zijlstra , Ingo Molnar , Stephen Boyd , Eric Biederman , Oleg Nesterov Subject: [patch V7 14/21] posix-timers: Move sequence logic into struct k_itimer References: <20241105063544.565410398@linutronix.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Date: Tue, 5 Nov 2024 09:14:48 +0100 (CET) Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Thomas Gleixner 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 Signed-off-by: Thomas Gleixner Reviewed-by: Frederic Weisbecker Acked-by: "Eric W. Biederman" --- V6: Update the comment in siginfo.h V5: New patch --- include/linux/posix-timers.h | 2 ++ include/uapi/asm-generic/siginfo.h | 2 +- kernel/signal.c | 8 +++----- kernel/time/posix-timers.c | 5 +---- 4 files changed, 7 insertions(+), 10 deletions(-) --- a/include/linux/posix-timers.h +++ b/include/linux/posix-timers.h @@ -162,6 +162,7 @@ static inline void posix_cputimers_init_ * @it_overrun: The overrun counter for pending signals * @it_overrun_last: The overrun at the time of the last delivered signal * @it_signal_seq: Sequence count to control signal delivery + * @it_sigqueue_seq: The sequence count at the point where the signal was = queued * @it_sigev_notify: The notify word of sigevent struct for signal delivery * @it_interval: The interval for periodic timers * @it_signal: Pointer to the creators signal struct @@ -184,6 +185,7 @@ struct k_itimer { s64 it_overrun; s64 it_overrun_last; unsigned int it_signal_seq; + unsigned int it_sigqueue_seq; int it_sigev_notify; enum pid_type it_pid_type; ktime_t it_interval; --- a/include/uapi/asm-generic/siginfo.h +++ b/include/uapi/asm-generic/siginfo.h @@ -46,7 +46,7 @@ union __sifields { __kernel_timer_t _tid; /* timer id */ int _overrun; /* overrun count */ sigval_t _sigval; /* same as below */ - int _sys_private; /* not to be passed to user */ + int _sys_private; /* Not used by the kernel. Historic leftover. Al= ways 0. */ } _timer; =20 /* POSIX.1b signals */ --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1976,12 +1976,10 @@ int posixtimer_send_sigqueue(struct k_it return -1; =20 /* - * Update @q::info::si_sys_private for posix timer signals with - * sighand locked to prevent a race against dequeue_signal() which - * decides based on si_sys_private whether to invoke - * posixtimer_rearm() or not. + * Update @tmr::sigqueue_seq for posix timer signals with sighand + * locked to prevent a race against dequeue_signal(). */ - q->info.si_sys_private =3D tmr->it_signal_seq; + tmr->it_sigqueue_seq =3D tmr->it_signal_seq; =20 ret =3D 1; /* the signal is ignored */ if (!prepare_signal(sig, t, false)) { --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -259,7 +259,7 @@ static bool __posixtimer_deliver_signal( * since the signal was queued. In either case, don't rearm and * drop the signal. */ - if (timr->it_signal_seq !=3D info->si_sys_private || WARN_ON_ONCE(!timr->= it_signal)) + if (timr->it_signal_seq !=3D timr->it_sigqueue_seq || WARN_ON_ONCE(!timr-= >it_signal)) return false; =20 if (!timr->it_interval || WARN_ON_ONCE(timr->it_status !=3D POSIX_TIMER_R= EQUEUE_PENDING)) @@ -297,9 +297,6 @@ bool posixtimer_deliver_signal(struct ke posixtimer_putref(timr); =20 spin_lock(¤t->sighand->siglock); - - /* Don't expose the si_sys_private value to userspace */ - info->si_sys_private =3D 0; return ret; }