From nobody Fri Dec 19 15:32:03 2025 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 4EF6677F14; Thu, 21 Dec 2023 22:19:55 +0000 (UTC) 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="1j7JdFHH"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="J4jZqYRp" Date: Thu, 21 Dec 2023 22:19:53 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1703197194; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=W6MZf3JnNH6fYMqsmBdfadcswG1f57d08m995ZyqhgA=; b=1j7JdFHHj+z7lS2WG51kLEJ+aMIdF1q1f/lXsHKLS9Dl8aCUYmwIU4k1vNP+bz4xRf5e/3 hUiAY6H0v0OhG3cVT+aPcs4bL4mKBIf5EWrkPjqnYXokc8LXujRLajzNeaREULjMXhlo8Q RDmmbXDs0tgRH/L7qImwgIUAvHryXoFrM6Ir8KVZEp2aReP4sJtp0DZZFR0l8vb61yx7Eb nnd7ZWaQuZg/JQaq/v6P71bnvh0oBru8edo1ZrKHNb0fhaZ98Sm+wNx2+n/M1W9zW9sm9f yCbjeIz/CrdXjPrV8f4oGnRbdfa/rI5B7XRkVwA76zFzgj0I3HBjBrPLe5sA+Q== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1703197194; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=W6MZf3JnNH6fYMqsmBdfadcswG1f57d08m995ZyqhgA=; b=J4jZqYRpjkv5ZPHufOoB7D1V9RAoq4XON59qjzjozktpFvRmBdIgsgiEx+qnwt6wmG/RW8 9uZcQFTOcX4exrCg== From: "tip-bot2 for Sven Schnelle" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: core/entry] entry: Move exit to usermode functions to header file Cc: Sven Schnelle , Thomas Gleixner , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20231218074520.1998026-2-svens@linux.ibm.com> References: <20231218074520.1998026-2-svens@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <170319719381.398.2807341208511949110.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the core/entry branch of tip: Commit-ID: d68019471995ba47e56a9da355df13a1cdb5bf7e Gitweb: https://git.kernel.org/tip/d68019471995ba47e56a9da355df13a1c= db5bf7e Author: Sven Schnelle AuthorDate: Mon, 18 Dec 2023 08:45:18 +01:00 Committer: Thomas Gleixner CommitterDate: Thu, 21 Dec 2023 23:12:18 +01:00 entry: Move exit to usermode functions to header file To allow inlining, move exit_to_user_mode() to entry-common.h. Signed-off-by: Sven Schnelle Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20231218074520.1998026-2-svens@linux.ibm.com --- include/linux/entry-common.h | 53 ++++++++++++++++++++++++++++++++++- kernel/entry/common.c | 52 +++++----------------------------- 2 files changed, 61 insertions(+), 44 deletions(-) diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h index d95ab85..6a6e98f 100644 --- a/include/linux/entry-common.h +++ b/include/linux/entry-common.h @@ -7,6 +7,10 @@ #include #include #include +#include +#include +#include +#include =20 #include =20 @@ -259,6 +263,43 @@ static __always_inline void arch_exit_to_user_mode(voi= d) { } void arch_do_signal_or_restart(struct pt_regs *regs); =20 /** + * exit_to_user_mode_loop - do any pending work before leaving to user spa= ce + */ +unsigned long exit_to_user_mode_loop(struct pt_regs *regs, + unsigned long ti_work); + +/** + * exit_to_user_mode_prepare - call exit_to_user_mode_loop() if required + * @regs: Pointer to pt_regs on entry stack + * + * 1) check that interrupts are disabled + * 2) call tick_nohz_user_enter_prepare() + * 3) call exit_to_user_mode_loop() if any flags from + * EXIT_TO_USER_MODE_WORK are set + * 4) check that interrupts are still disabled + */ +static __always_inline void exit_to_user_mode_prepare(struct pt_regs *regs) +{ + unsigned long ti_work; + + lockdep_assert_irqs_disabled(); + + /* Flush pending rcuog wakeup before the last need_resched() check */ + tick_nohz_user_enter_prepare(); + + ti_work =3D read_thread_flags(); + if (unlikely(ti_work & EXIT_TO_USER_MODE_WORK)) + ti_work =3D exit_to_user_mode_loop(regs, ti_work); + + arch_exit_to_user_mode_prepare(regs, ti_work); + + /* Ensure that kernel state is sane for a return to userspace */ + kmap_assert_nomap(); + lockdep_assert_irqs_disabled(); + lockdep_sys_exit(); +} + +/** * exit_to_user_mode - Fixup state when exiting to user mode * * Syscall/interrupt exit enables interrupts, but the kernel state is @@ -276,7 +317,17 @@ void arch_do_signal_or_restart(struct pt_regs *regs); * non-instrumentable. * The caller has to invoke syscall_exit_to_user_mode_work() before this. */ -void exit_to_user_mode(void); +static __always_inline void exit_to_user_mode(void) +{ + instrumentation_begin(); + trace_hardirqs_on_prepare(); + lockdep_hardirqs_on_prepare(); + instrumentation_end(); + + user_enter_irqoff(); + arch_exit_to_user_mode(); + lockdep_hardirqs_on(CALLER_ADDR0); +} =20 /** * syscall_exit_to_user_mode_work - Handle work before returning to user m= ode diff --git a/kernel/entry/common.c b/kernel/entry/common.c index d7ee4bc..7f8f8c1 100644 --- a/kernel/entry/common.c +++ b/kernel/entry/common.c @@ -123,29 +123,16 @@ noinstr void syscall_enter_from_user_mode_prepare(str= uct pt_regs *regs) instrumentation_end(); } =20 -/* See comment for exit_to_user_mode() in entry-common.h */ -static __always_inline void __exit_to_user_mode(void) -{ - instrumentation_begin(); - trace_hardirqs_on_prepare(); - lockdep_hardirqs_on_prepare(); - instrumentation_end(); - - user_enter_irqoff(); - arch_exit_to_user_mode(); - lockdep_hardirqs_on(CALLER_ADDR0); -} - -void noinstr exit_to_user_mode(void) -{ - __exit_to_user_mode(); -} - /* Workaround to allow gradual conversion of architecture code */ void __weak arch_do_signal_or_restart(struct pt_regs *regs) { } =20 -static unsigned long exit_to_user_mode_loop(struct pt_regs *regs, - unsigned long ti_work) +/** + * exit_to_user_mode_loop - do any pending work before leaving to user spa= ce + * @regs: Pointer to pt_regs on entry stack + * @ti_work: TIF work flags as read by the caller + */ +__always_inline unsigned long exit_to_user_mode_loop(struct pt_regs *regs, + unsigned long ti_work) { /* * Before returning to user space ensure that all pending work @@ -190,27 +177,6 @@ static unsigned long exit_to_user_mode_loop(struct pt_= regs *regs, return ti_work; } =20 -static void exit_to_user_mode_prepare(struct pt_regs *regs) -{ - unsigned long ti_work; - - lockdep_assert_irqs_disabled(); - - /* Flush pending rcuog wakeup before the last need_resched() check */ - tick_nohz_user_enter_prepare(); - - ti_work =3D read_thread_flags(); - if (unlikely(ti_work & EXIT_TO_USER_MODE_WORK)) - ti_work =3D exit_to_user_mode_loop(regs, ti_work); - - arch_exit_to_user_mode_prepare(regs, ti_work); - - /* Ensure that kernel state is sane for a return to userspace */ - kmap_assert_nomap(); - lockdep_assert_irqs_disabled(); - lockdep_sys_exit(); -} - /* * If SYSCALL_EMU is set, then the only reason to report is when * SINGLESTEP is set (i.e. PTRACE_SYSEMU_SINGLESTEP). This syscall @@ -295,7 +261,7 @@ __visible noinstr void syscall_exit_to_user_mode(struct= pt_regs *regs) instrumentation_begin(); __syscall_exit_to_user_mode_work(regs); instrumentation_end(); - __exit_to_user_mode(); + exit_to_user_mode(); } =20 noinstr void irqentry_enter_from_user_mode(struct pt_regs *regs) @@ -308,7 +274,7 @@ noinstr void irqentry_exit_to_user_mode(struct pt_regs = *regs) instrumentation_begin(); exit_to_user_mode_prepare(regs); instrumentation_end(); - __exit_to_user_mode(); + exit_to_user_mode(); } =20 noinstr irqentry_state_t irqentry_enter(struct pt_regs *regs)