From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
linux-serial@vger.kernel.org,
Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Subject: [PATCH v1 4/4] serial: core: Refactor uart_unlock_and_check_sysrq()
Date: Tue, 10 Mar 2020 15:20:04 +0200 [thread overview]
Message-ID: <20200310132004.86367-4-andriy.shevchenko@linux.intel.com> (raw)
In-Reply-To: <20200310132004.86367-1-andriy.shevchenko@linux.intel.com>
Refactor uart_unlock_and_check_sysrq() to:
- explicitly show that we release a port lock which makes
static analyzers happy:
CHECK drivers/tty/serial/serial_core.c
.../serial_core.c:3290:17: warning: context imbalance in 'uart_unlock_and_check_sysrq' - unexpected unlock
- use flags instead of irqflags to avoid confusion with IRQ flags
- provide one return point
- be more compact
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/tty/serial/serial_core.c | 22 ++++++++++------------
include/linux/serial_core.h | 3 +--
2 files changed, 11 insertions(+), 14 deletions(-)
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index e3f8e641e3a7..ee51cf87e409 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -3286,22 +3286,20 @@ int uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch)
}
EXPORT_SYMBOL_GPL(uart_prepare_sysrq_char);
-void uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long irqflags)
+void uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long flags)
+__releases(&port->lock)
{
int sysrq_ch;
- if (!port->has_sysrq) {
- spin_unlock_irqrestore(&port->lock, irqflags);
- return;
+ if (port->has_sysrq) {
+ sysrq_ch = port->sysrq_ch;
+ port->sysrq_ch = 0;
+ spin_unlock_irqrestore(&port->lock, flags);
+ if (sysrq_ch)
+ handle_sysrq(sysrq_ch);
+ } else {
+ spin_unlock_irqrestore(&port->lock, flags);
}
-
- sysrq_ch = port->sysrq_ch;
- port->sysrq_ch = 0;
-
- spin_unlock_irqrestore(&port->lock, irqflags);
-
- if (sysrq_ch)
- handle_sysrq(sysrq_ch);
}
EXPORT_SYMBOL_GPL(uart_unlock_and_check_sysrq);
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 7a025042e0bb..cab896c60e35 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -447,8 +447,7 @@ extern void uart_insert_char(struct uart_port *port, unsigned int status,
extern int uart_handle_sysrq_char(struct uart_port *port, unsigned int ch);
extern int uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch);
-extern void uart_unlock_and_check_sysrq(struct uart_port *port,
- unsigned long irqflags);
+extern void uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long flags);
extern int uart_handle_break(struct uart_port *port);
/*
--
2.25.1
next prev parent reply other threads:[~2020-03-10 13:20 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-10 13:20 [PATCH v1 1/4] serial: core: Use string length for SysRq magic sequence Andy Shevchenko
2020-03-10 13:20 ` [PATCH v1 2/4] serial: core: Print escaped SysRq Magic sequence if enabled Andy Shevchenko
2020-03-10 14:40 ` Dmitry Safonov
2020-03-10 13:20 ` [PATCH v1 3/4] serial: core: Use uart_console() helper in SysRq code Andy Shevchenko
2020-03-10 14:43 ` Dmitry Safonov
2020-03-10 13:20 ` Andy Shevchenko [this message]
2020-03-10 14:48 ` [PATCH v1 4/4] serial: core: Refactor uart_unlock_and_check_sysrq() Dmitry Safonov
2020-03-10 15:30 ` Andy Shevchenko
2020-03-10 14:38 ` [PATCH v1 1/4] serial: core: Use string length for SysRq magic sequence Dmitry Safonov
2020-03-10 14:57 ` Andy Shevchenko
2020-03-10 15:33 ` Andy Shevchenko
2020-03-10 15:57 ` Dmitry Safonov
2020-03-10 16:48 ` Andy Shevchenko
2020-03-10 17:06 ` Dmitry Safonov
2020-03-10 17:06 ` Dmitry Safonov
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