summaryrefslogtreecommitdiff
path: root/kernel/softirq.c
diff options
context:
space:
mode:
authorArnd Bergmann <arnd@arndb.de>2013-06-20 02:14:59 +0200
committerArnd Bergmann <arnd@arndb.de>2013-06-20 02:15:45 +0200
commite5051b8472c2fde91e44d906c9a2e516a10b60b2 (patch)
treeb7c27378ca981a7bcf86639db7b0cde834feb0b6 /kernel/softirq.c
parentc3b693d1d63444afe4fbf809d8a311b63741e503 (diff)
parent3bfbc6cd9b41f937a134ba65a4a1eefba062b9a8 (diff)
Merge tag 'imx-soc-3.11' of git://git.linaro.org/people/shawnguo/linux-2.6 into next/soc
From Shawn Guo: imx soc changes for 3.11: * New SoCs i.MX6 Sololite and Vybrid VF610 support * imx5 and imx6 clock fixes and additions * Update clock driver to use of_clk_init() function * Refactor restart routine mxc_restart() to get it work for DT boot as well * Clean up mxc specific ulpi access ops * imx defconfig updates * tag 'imx-soc-3.11' of git://git.linaro.org/people/shawnguo/linux-2.6: (29 commits) ARM: imx_v6_v7_defconfig: Enable Vybrid VF610 ARM: imx_v6_v7_defconfig: Enable imx-wm8962 by default ARM: clk-imx6qdl: Add clko1 configuration for imx6qdl-sabresd ARM: imx_v6_v7_defconfig: Enable PWM and backlight options ARM: imx: Remove mxc specific ulpi access ops ARM: imx: add initial support for VF610 ARM: imx: add VF610 clock support ARM: imx_v6_v7_defconfig: enable parallel display ARM: imx: clk: No need to initialize phandle struct ARM: imx: irq-common: Include header to avoid sparse warning ARM: imx: Enable mx6 solo-lite support ARM: imx6: use common of_clk_init() call to initialize clocks ARM: imx6q: call of_clk_init() to register fixed rate clocks ARM: imx: imx_v6_v7_defconfig: Select CONFIG_DRM_IMX_TVE ARM: i.MX6: clk: add different DualLite MLB clock config ARM i.MX5: Add S/PDIF clocks ARM i.MX53: Add SATA clock ARM: imx6q: clk: add the eim_slow clock ARM: imx: remove MLB PLL from pllv3 ARM: imx: disable pll8_mlb in mx6q_clks ... Conflicts: arch/arm/Kconfig.debug (simple add/add conflict) Includes an update to 3.10-rc6 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'kernel/softirq.c')
-rw-r--r--kernel/softirq.c13
1 files changed, 10 insertions, 3 deletions
diff --git a/kernel/softirq.c b/kernel/softirq.c
index b5197dcb0dad..3d6833f125d3 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -195,8 +195,12 @@ void local_bh_enable_ip(unsigned long ip)
EXPORT_SYMBOL(local_bh_enable_ip);
/*
- * We restart softirq processing for at most 2 ms,
- * and if need_resched() is not set.
+ * We restart softirq processing for at most MAX_SOFTIRQ_RESTART times,
+ * but break the loop if need_resched() is set or after 2 ms.
+ * The MAX_SOFTIRQ_TIME provides a nice upper bound in most cases, but in
+ * certain cases, such as stop_machine(), jiffies may cease to
+ * increment and so we need the MAX_SOFTIRQ_RESTART limit as
+ * well to make sure we eventually return from this method.
*
* These limits have been established via experimentation.
* The two things to balance is latency against fairness -
@@ -204,6 +208,7 @@ EXPORT_SYMBOL(local_bh_enable_ip);
* should not be able to lock up the box.
*/
#define MAX_SOFTIRQ_TIME msecs_to_jiffies(2)
+#define MAX_SOFTIRQ_RESTART 10
asmlinkage void __do_softirq(void)
{
@@ -212,6 +217,7 @@ asmlinkage void __do_softirq(void)
unsigned long end = jiffies + MAX_SOFTIRQ_TIME;
int cpu;
unsigned long old_flags = current->flags;
+ int max_restart = MAX_SOFTIRQ_RESTART;
/*
* Mask out PF_MEMALLOC s current task context is borrowed for the
@@ -265,7 +271,8 @@ restart:
pending = local_softirq_pending();
if (pending) {
- if (time_before(jiffies, end) && !need_resched())
+ if (time_before(jiffies, end) && !need_resched() &&
+ --max_restart)
goto restart;
wakeup_softirqd();