From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH 3/4] sparc64: convert spinlock_t to raw_spinlock_t in mmu_context_t Date: Tue, 04 Mar 2014 14:10:03 -0500 (EST) Message-ID: <20140304.141003.1969905483115684548.davem@davemloft.net> References: <359241392801938@web24j.yandex.ru> <530D9D1C.1060905@oracle.com> <39171393599083@web13h.yandex.ru> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: allen.pais@oracle.com, linux-rt-users@vger.kernel.org, sparclinux@vger.kernel.org, bigeasy@linutronix.de To: tkhai@yandex.ru Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:35930 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753420AbaCDTKG (ORCPT ); Tue, 4 Mar 2014 14:10:06 -0500 In-Reply-To: <39171393599083@web13h.yandex.ru> Sender: linux-rt-users-owner@vger.kernel.org List-ID: From: Kirill Tkhai Date: Fri, 28 Feb 2014 18:51:23 +0400 > This should be fixed like that's done for 8250 > [patch drivers-serial-cleanup-locking-for-rt.patch] Like the patch below? Is this transformation legitimate outside of the -rt tree? I wish the commit messages for the 8250 change was more verbose, explaining exactly why this is needed. And if it's needed, all the sparc serial/console drivers need this too. diff --git a/drivers/tty/serial/sunhv.c b/drivers/tty/serial/sunhv.c index cf86e72..dc697ce 100644 --- a/drivers/tty/serial/sunhv.c +++ b/drivers/tty/serial/sunhv.c @@ -433,13 +433,10 @@ static void sunhv_console_write_paged(struct console *con, const char *s, unsign unsigned long flags; int locked = 1; - local_irq_save(flags); - if (port->sysrq) { - locked = 0; - } else if (oops_in_progress) { - locked = spin_trylock(&port->lock); - } else - spin_lock(&port->lock); + if (port->sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&port->lock, flags); + else + spin_lock_irqsave(&port->lock, flags); while (n > 0) { unsigned long ra = __pa(con_write_page); @@ -470,8 +467,7 @@ static void sunhv_console_write_paged(struct console *con, const char *s, unsign } if (locked) - spin_unlock(&port->lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&port->lock, flags); } static inline void sunhv_console_putchar(struct uart_port *port, char c) @@ -492,7 +488,10 @@ static void sunhv_console_write_bychar(struct console *con, const char *s, unsig unsigned long flags; int i, locked = 1; - local_irq_save(flags); + if (port->sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&port->lock, flags); + else + spin_lock_irqsave(&port->lock, flags); if (port->sysrq) { locked = 0; } else if (oops_in_progress) { @@ -507,8 +506,7 @@ static void sunhv_console_write_bychar(struct console *con, const char *s, unsig } if (locked) - spin_unlock(&port->lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&port->lock, flags); } static struct console sunhv_console = {