From: Alexander Kochetkov <al.kochet@gmail.com>
To: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
linux-rockchip@lists.infradead.org
Cc: Thomas Gleixner <tglx@linutronix.de>,
Heiko Stuebner <heiko@sntech.de>,
Mark Rutland <mark.rutland@arm.com>,
Rob Herring <robh+dt@kernel.org>,
Russell King <linux@armlinux.org.uk>,
Caesar Wang <wxt@rock-chips.com>,
Huang Tao <huangtao@rock-chips.com>,
Daniel Lezcano <daniel.lezcano@linaro.org>,
Alexander Kochetkov <al.kochet@gmail.com>
Subject: [PATCH v3 13/13] clocksource/drivers/rockchip_timer: Prevent ftrace recursion
Date: Tue, 29 Nov 2016 16:45:18 +0300 [thread overview]
Message-ID: <1480427118-5126-14-git-send-email-al.kochet@gmail.com> (raw)
In-Reply-To: <1480427118-5126-1-git-send-email-al.kochet@gmail.com>
Currently rockchip_timer can be used as a scheduler clock. We properly
marked rk_timer_sched_clock_read() as notrace but we then call another
function rk_timer_counter_read() that _wasn't_ notrace.
Having a traceable function in the sched_clock() path leads to a recursion
within ftrace and a kernel crash.
Fix this by adding an extra notrace function to keep other users of
rk_timer_counter_read() traceable.
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
---
drivers/clocksource/rockchip_timer.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/clocksource/rockchip_timer.c b/drivers/clocksource/rockchip_timer.c
index 1af80a0..a127822 100644
--- a/drivers/clocksource/rockchip_timer.c
+++ b/drivers/clocksource/rockchip_timer.c
@@ -87,7 +87,7 @@ static void rk_timer_update_counter(u64 cycles, struct rk_timer *timer)
writel_relaxed(upper, timer->base + TIMER_LOAD_COUNT1);
}
-static u64 rk_timer_counter_read(struct rk_timer *timer)
+static u64 notrace _rk_timer_counter_read(struct rk_timer *timer)
{
u64 counter;
u32 lower;
@@ -106,6 +106,11 @@ static u64 rk_timer_counter_read(struct rk_timer *timer)
return counter;
}
+static u64 rk_timer_counter_read(struct rk_timer *timer)
+{
+ return _rk_timer_counter_read(timer);
+}
+
static void rk_timer_interrupt_clear(struct rk_timer *timer)
{
writel_relaxed(1, timer->base + TIMER_INT_STATUS);
@@ -168,7 +173,7 @@ static u64 notrace rk_timer_sched_clock_read(void)
{
struct rk_clocksource *_cs = &cs_timer;
- return ~rk_timer_counter_read(&_cs->timer);
+ return ~_rk_timer_counter_read(&_cs->timer);
}
static int __init rk_timer_init(struct device_node *np, u32 ctrl_reg)
--
1.7.9.5
next prev parent reply other threads:[~2016-11-29 13:46 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-28 14:31 [PATCHv2 00/11] Implement clocksource for rockchip SoC using rockchip timer Alexander Kochetkov
2016-11-28 14:31 ` [PATCHv2 01/11] dt-bindings: clarify compatible property for rockchip timers Alexander Kochetkov
2016-11-28 14:31 ` [PATCHv2 02/11] ARM: dts: rockchip: update compatible property for rk3228 timer Alexander Kochetkov
2016-11-28 14:31 ` [PATCHv2 03/11] ARM: dts: rockchip: update compatible property for rk3229 timer Alexander Kochetkov
2016-11-28 14:31 ` [PATCHv2 04/11] ARM: dts: rockchip: add timer entries to rk3188 dtsi Alexander Kochetkov
2016-11-28 14:31 ` [PATCHv2 05/11] clocksource/drivers/rockchip_timer: split bc_timer into rk_timer and rk_clock_event_device Alexander Kochetkov
2016-11-28 14:31 ` [PATCHv2 06/11] clocksource/drivers/rockchip_timer: low level routines take rk_timer as parameter Alexander Kochetkov
2016-11-28 14:31 ` [PATCHv2 07/11] clocksource/drivers/rockchip_timer: drop unused rk_base() and rk_ctrl() Alexander Kochetkov
2016-11-28 14:31 ` [PATCHv2 08/11] clocksource/drivers/rockchip_timer: move TIMER_INT_UNMASK out of rk_timer_enable() Alexander Kochetkov
2016-11-28 14:31 ` [PATCHv2 09/11] clocksource/drivers/rockchip_timer: implement loading 64bit value into timer Alexander Kochetkov
2016-11-28 14:31 ` [PATCHv2 10/11] clocksource/drivers/rockchip_timer: implement reading 64bit value from timer Alexander Kochetkov
2016-11-28 14:31 ` [PATCHv2 11/11] clocksource/drivers/rockchip_timer: implement clocksource timer Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 00/13] Implement clocksource for rockchip SoC using rockchip timer Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 01/13] dt-bindings: clarify compatible property for rockchip timers Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 02/13] ARM: dts: rockchip: update compatible property for rk3228 timer Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 03/13] ARM: dts: rockchip: update compatible property for rk3229 timer Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 04/13] ARM: dts: rockchip: add timer entries to rk3188 dtsi Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 05/13] ARM: dts: rockchip: disable arm-global-timer for rk3188 Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 06/13] clocksource/drivers/rockchip_timer: split bc_timer into rk_timer and rk_clock_event_device Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 07/13] clocksource/drivers/rockchip_timer: low level routines take rk_timer as parameter Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 08/13] clocksource/drivers/rockchip_timer: drop unused rk_base() and rk_ctrl() Alexander Kochetkov
2016-11-29 15:03 ` Heiko Stübner
2016-11-29 13:45 ` [PATCH v3 09/13] clocksource/drivers/rockchip_timer: move TIMER_INT_UNMASK out of rk_timer_enable() Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 10/13] clocksource/drivers/rockchip_timer: implement loading 64bit value into timer Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 11/13] clocksource/drivers/rockchip_timer: implement reading 64bit value from timer Alexander Kochetkov
2016-11-29 13:45 ` [PATCH v3 12/13] clocksource/drivers/rockchip_timer: implement clocksource timer Alexander Kochetkov
2016-11-29 13:45 ` Alexander Kochetkov [this message]
2016-11-29 15:01 ` [PATCH v3 13/13] clocksource/drivers/rockchip_timer: Prevent ftrace recursion Heiko Stübner
2016-11-29 15:36 ` Alexander Kochetkov
2016-11-29 16:14 ` [PATCH v4 0/9] Implement clocksource for rockchip SoC using rockchip timer Alexander Kochetkov
2016-11-29 16:14 ` [PATCH v4 1/9] dt-bindings: clarify compatible property for rockchip timers Alexander Kochetkov
2016-12-05 22:22 ` Rob Herring
2016-11-29 16:14 ` [PATCH v4 2/9] ARM: dts: rockchip: update compatible property for rk3228 timer Alexander Kochetkov
2017-01-23 15:40 ` Daniel Lezcano
2017-01-23 16:12 ` Heiko Stübner
2017-01-23 16:13 ` Alexander Kochetkov
2016-11-29 16:14 ` [PATCH v4 3/9] ARM: dts: rockchip: update compatible property for rk3229 timer Alexander Kochetkov
2016-11-29 16:14 ` [PATCH v4 4/9] ARM: dts: rockchip: add timer entries to rk3188 SoC Alexander Kochetkov
2016-11-29 16:14 ` [PATCH v4 5/9] ARM: dts: rockchip: disable arm-global-timer for rk3188 Alexander Kochetkov
2017-01-23 16:14 ` Heiko Stübner
2016-11-29 16:14 ` [PATCH v4 6/9] clocksource/drivers/rockchip_timer: split bc_timer into rk_timer and rk_clock_event_device Alexander Kochetkov
2017-01-23 16:26 ` Daniel Lezcano
2017-01-23 16:45 ` Alexander Kochetkov
2016-11-29 16:14 ` [PATCH v4 7/9] clocksource/drivers/rockchip_timer: low level routines take rk_timer as parameter Alexander Kochetkov
2016-11-29 16:14 ` [PATCH v4 8/9] clocksource/drivers/rockchip_timer: move TIMER_INT_UNMASK out of rk_timer_enable() Alexander Kochetkov
2016-11-29 16:14 ` [PATCH v4 9/9] clocksource/drivers/rockchip_timer: implement clocksource timer Alexander Kochetkov
2017-01-23 17:09 ` Heiko Stübner
2016-12-21 14:21 ` [PATCH v4 0/9] Implement clocksource for rockchip SoC using rockchip timer Alexander Kochetkov
2017-01-23 14:47 ` Daniel Lezcano
2017-01-23 17:12 ` Heiko Stübner
2017-01-23 17:24 ` Alexander Kochetkov
2017-01-23 17:57 ` Daniel Lezcano
2017-01-26 11:08 ` Alexander Kochetkov
2017-01-26 13:19 ` Daniel Lezcano
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