From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 E0D582139C4; Tue, 18 Feb 2025 20:27:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739910429; cv=none; b=Su5lkSmrcDoJ7g9s7zsoIhu8X2q1M26YjMkwoIAhzIPhPU8x31djKLhiZftUdA0stvoe0iCvmDQYEnySx7Qrt8t4l3qpYXkgEE6WgTXo/U1Vm82THWPi09VonXIDyRiEmhUfr6esDLujPTiNRRgzxDKMEC8QXoLkjmd/qUWqIHg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739910429; c=relaxed/simple; bh=2sohyi4xEaTC1NwXXc7Lqb9YoGirX8UCnEFaPIM4CvM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=ov5PouKVh1FBASFhdkHNyaqUJnAZhyRXg3mJyDNRBIOJbWXsKeOK6uM9gMYt9zNsx914nxgiHkN+Izz4zRVZdOm+omqNjmpVSnrkRZFFIsrsTCdnjUHKTEIw+ua05FnaKr83eTXV1h7XR7cOfm7wfoNPa5hlkCxhfvHZ7S0pJQE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bMVYB0No; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="bMVYB0No" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B4626C4CEE2; Tue, 18 Feb 2025 20:27:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1739910428; bh=2sohyi4xEaTC1NwXXc7Lqb9YoGirX8UCnEFaPIM4CvM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bMVYB0No8vuUs/c2IoJS1UPeFhxRLp+5e/+5RrmW7OYTxf1RFCnm57ILm3Cs4eK0q y/iai5Q7uMI2HiFAL/c4dY1I4sCQTvkNFYzKaHicdsiEvw07kqar895v5Pa65dQIK2 lUOM8HAQdKA9SZm7lOF+ujOGYvXPiaHEMAmBIOjWiXoamlurGkhnQqgTIuuLG7hAYM dk+pkrtEf0KWWafhQEskDx8bbb9UCQ1wlIm/CCAHPtv+bDKFZQnftdkaNgd5YCA2HD y0YinMNdqA2SLtPUykm3noJCMLc5wzg1lChDCjbwtrZ0xEVdfckbNbV8DfW6yJzKji zIyjWAqscnp1A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Johannes Berg , Richard Weinberger , Sasha Levin , anton.ivanov@cambridgegreys.com, johannes@sipsolutions.net, benjamin.berg@intel.com, thehajime@gmail.com, linux-um@lists.infradead.org Subject: [PATCH AUTOSEL 6.12 23/31] um: convert irq_lock to raw spinlock Date: Tue, 18 Feb 2025 15:26:09 -0500 Message-Id: <20250218202619.3592630-23-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250218202619.3592630-1-sashal@kernel.org> References: <20250218202619.3592630-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.12.15 Content-Transfer-Encoding: 8bit From: Johannes Berg [ Upstream commit 96178631c3f53398044ed437010f7632ad764bf8 ] Since this is deep in the architecture, and the code is called nested into other deep management code, this really needs to be a raw spinlock. Convert it. Link: https://patch.msgid.link/20250110125550.32479-8-johannes@sipsolutions.net Signed-off-by: Johannes Berg Signed-off-by: Richard Weinberger Signed-off-by: Sasha Levin --- arch/um/kernel/irq.c | 79 ++++++++++++++++++++++++++------------------ 1 file changed, 47 insertions(+), 32 deletions(-) diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c index 534e91797f892..ebf8012bbec45 100644 --- a/arch/um/kernel/irq.c +++ b/arch/um/kernel/irq.c @@ -52,7 +52,7 @@ struct irq_entry { bool sigio_workaround; }; -static DEFINE_SPINLOCK(irq_lock); +static DEFINE_RAW_SPINLOCK(irq_lock); static LIST_HEAD(active_fds); static DECLARE_BITMAP(irqs_allocated, UM_LAST_SIGNAL_IRQ); static bool irqs_suspended; @@ -257,7 +257,7 @@ static struct irq_entry *get_irq_entry_by_fd(int fd) return NULL; } -static void free_irq_entry(struct irq_entry *to_free, bool remove) +static void remove_irq_entry(struct irq_entry *to_free, bool remove) { if (!to_free) return; @@ -265,7 +265,6 @@ static void free_irq_entry(struct irq_entry *to_free, bool remove) if (remove) os_del_epoll_fd(to_free->fd); list_del(&to_free->list); - kfree(to_free); } static bool update_irq_entry(struct irq_entry *entry) @@ -286,17 +285,19 @@ static bool update_irq_entry(struct irq_entry *entry) return false; } -static void update_or_free_irq_entry(struct irq_entry *entry) +static struct irq_entry *update_or_remove_irq_entry(struct irq_entry *entry) { - if (!update_irq_entry(entry)) - free_irq_entry(entry, false); + if (update_irq_entry(entry)) + return NULL; + remove_irq_entry(entry, false); + return entry; } static int activate_fd(int irq, int fd, enum um_irq_type type, void *dev_id, void (*timetravel_handler)(int, int, void *, struct time_travel_event *)) { - struct irq_entry *irq_entry; + struct irq_entry *irq_entry, *to_free = NULL; int err, events = os_event_mask(type); unsigned long flags; @@ -304,9 +305,10 @@ static int activate_fd(int irq, int fd, enum um_irq_type type, void *dev_id, if (err < 0) goto out; - spin_lock_irqsave(&irq_lock, flags); + raw_spin_lock_irqsave(&irq_lock, flags); irq_entry = get_irq_entry_by_fd(fd); if (irq_entry) { +already: /* cannot register the same FD twice with the same type */ if (WARN_ON(irq_entry->reg[type].events)) { err = -EALREADY; @@ -316,11 +318,22 @@ static int activate_fd(int irq, int fd, enum um_irq_type type, void *dev_id, /* temporarily disable to avoid IRQ-side locking */ os_del_epoll_fd(fd); } else { - irq_entry = kzalloc(sizeof(*irq_entry), GFP_ATOMIC); - if (!irq_entry) { - err = -ENOMEM; - goto out_unlock; + struct irq_entry *new; + + /* don't restore interrupts */ + raw_spin_unlock(&irq_lock); + new = kzalloc(sizeof(*irq_entry), GFP_ATOMIC); + if (!new) { + local_irq_restore(flags); + return -ENOMEM; } + raw_spin_lock(&irq_lock); + irq_entry = get_irq_entry_by_fd(fd); + if (irq_entry) { + to_free = new; + goto already; + } + irq_entry = new; irq_entry->fd = fd; list_add_tail(&irq_entry->list, &active_fds); maybe_sigio_broken(fd); @@ -339,12 +352,11 @@ static int activate_fd(int irq, int fd, enum um_irq_type type, void *dev_id, #endif WARN_ON(!update_irq_entry(irq_entry)); - spin_unlock_irqrestore(&irq_lock, flags); - - return 0; + err = 0; out_unlock: - spin_unlock_irqrestore(&irq_lock, flags); + raw_spin_unlock_irqrestore(&irq_lock, flags); out: + kfree(to_free); return err; } @@ -358,19 +370,20 @@ void free_irq_by_fd(int fd) struct irq_entry *to_free; unsigned long flags; - spin_lock_irqsave(&irq_lock, flags); + raw_spin_lock_irqsave(&irq_lock, flags); to_free = get_irq_entry_by_fd(fd); - free_irq_entry(to_free, true); - spin_unlock_irqrestore(&irq_lock, flags); + remove_irq_entry(to_free, true); + raw_spin_unlock_irqrestore(&irq_lock, flags); + kfree(to_free); } EXPORT_SYMBOL(free_irq_by_fd); static void free_irq_by_irq_and_dev(unsigned int irq, void *dev) { - struct irq_entry *entry; + struct irq_entry *entry, *to_free = NULL; unsigned long flags; - spin_lock_irqsave(&irq_lock, flags); + raw_spin_lock_irqsave(&irq_lock, flags); list_for_each_entry(entry, &active_fds, list) { enum um_irq_type i; @@ -386,12 +399,13 @@ static void free_irq_by_irq_and_dev(unsigned int irq, void *dev) os_del_epoll_fd(entry->fd); reg->events = 0; - update_or_free_irq_entry(entry); + to_free = update_or_remove_irq_entry(entry); goto out; } } out: - spin_unlock_irqrestore(&irq_lock, flags); + raw_spin_unlock_irqrestore(&irq_lock, flags); + kfree(to_free); } void deactivate_fd(int fd, int irqnum) @@ -402,7 +416,7 @@ void deactivate_fd(int fd, int irqnum) os_del_epoll_fd(fd); - spin_lock_irqsave(&irq_lock, flags); + raw_spin_lock_irqsave(&irq_lock, flags); entry = get_irq_entry_by_fd(fd); if (!entry) goto out; @@ -414,9 +428,10 @@ void deactivate_fd(int fd, int irqnum) entry->reg[i].events = 0; } - update_or_free_irq_entry(entry); + entry = update_or_remove_irq_entry(entry); out: - spin_unlock_irqrestore(&irq_lock, flags); + raw_spin_unlock_irqrestore(&irq_lock, flags); + kfree(entry); ignore_sigio_fd(fd); } @@ -546,7 +561,7 @@ void um_irqs_suspend(void) irqs_suspended = true; - spin_lock_irqsave(&irq_lock, flags); + raw_spin_lock_irqsave(&irq_lock, flags); list_for_each_entry(entry, &active_fds, list) { enum um_irq_type t; bool clear = true; @@ -579,7 +594,7 @@ void um_irqs_suspend(void) !__ignore_sigio_fd(entry->fd); } } - spin_unlock_irqrestore(&irq_lock, flags); + raw_spin_unlock_irqrestore(&irq_lock, flags); } void um_irqs_resume(void) @@ -588,7 +603,7 @@ void um_irqs_resume(void) unsigned long flags; - spin_lock_irqsave(&irq_lock, flags); + raw_spin_lock_irqsave(&irq_lock, flags); list_for_each_entry(entry, &active_fds, list) { if (entry->suspended) { int err = os_set_fd_async(entry->fd); @@ -602,7 +617,7 @@ void um_irqs_resume(void) } } } - spin_unlock_irqrestore(&irq_lock, flags); + raw_spin_unlock_irqrestore(&irq_lock, flags); irqs_suspended = false; send_sigio_to_self(); @@ -613,7 +628,7 @@ static int normal_irq_set_wake(struct irq_data *d, unsigned int on) struct irq_entry *entry; unsigned long flags; - spin_lock_irqsave(&irq_lock, flags); + raw_spin_lock_irqsave(&irq_lock, flags); list_for_each_entry(entry, &active_fds, list) { enum um_irq_type t; @@ -628,7 +643,7 @@ static int normal_irq_set_wake(struct irq_data *d, unsigned int on) } } unlock: - spin_unlock_irqrestore(&irq_lock, flags); + raw_spin_unlock_irqrestore(&irq_lock, flags); return 0; } #else -- 2.39.5