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Subject[GIT PULL] timer subsystem changes for v4.11
Linus,

Please pull the latest timers-core-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers-core-for-linus

# HEAD: 336a9cde10d641e70bac67d90ae91b3190c3edca hrtimer: Catch invalid clockids again

The main changes in this cycle were:

- Update clocksource drivers (Bhumika Goyal, Chris Brandt, David Engraf, Ding
Tianhong, Linus Walleij, Daniel Lezcano)

- Make delay() work early during bootup and improve its documentation

(Jiri Slaby, Russell King)

- Remove the CONFIG_TIMER_STATS (/proc/timer_stats) debugging facility (Kees Cook)

- Detect invalid clockids (Marc Zyngier)

- Improve timer broadcast lock scalability (Waiman Long)

- ... plus various smaller fixes and cleanups.

Thanks,

Ingo

------------------>
Bhumika Goyal (1):
clocksource/drivers/arm_arch_timer:: Mark cyclecounter __ro_after_init

Chris Brandt (2):
clocksource/drivers/ostm: Document renesas-ostm timer DT bindings
clocksource/drivers/ostm: Add renesas-ostm timer driver

Daniel Lezcano (1):
clockevents: Add a clkevt-of mechanism like clksrc-of

David Engraf (1):
clocksource/drivers/tcb_clksrc: Use 32 bit tcb as sched_clock

Ding Tianhong (4):
clocksource/drivers/arm_arch_timer: Add dt binding for hisilicon-161010101 erratum
clocksource/drivers/arm_arch_timer: Remove fsl-a008585 parameter
clocksource/drivers/arm_arch_timer: Introduce generic errata handling infrastructure
clocksource/drivers/arm_arch_timer: Work around Hisilicon erratum 161010101

Geliang Tang (1):
timerqueue: Use rb_entry_safe() instead of open-coding it

Jiri Slaby (1):
x86/timer: Make delay() work during early bootup

Kees Cook (1):
time: Remove CONFIG_TIMER_STATS

Linus Walleij (2):
clocksource: add DT bindings for Cortina Gemini
clocksource/drivers/gemini: Add driver for the Cortina Gemini

Marc Zyngier (1):
hrtimer: Catch invalid clockids again

Mars Cheng (1):
timer_list: Remove useless cast when printing

Nicolas Pitre (1):
timers: Omit POSIX timer stuff from task_struct when disabled

Peter Zijlstra (1):
math64, timers: Fix 32bit mul_u64_u32_shr() and friends

Russell King (1):
delay: Add explanation of udelay() inaccuracy

Stephen Boyd (1):
timekeeping: Remove unused timekeeping_{get,set}_tai_offset()

Sudip Mukherjee (1):
math64, tile: Fix build failure

Thomas Gleixner (1):
timerfd: Protect the might cancel mechanism proper

Waiman Long (1):
tick/broadcast: Reduce lock cacheline contention


Documentation/admin-guide/kernel-parameters.txt | 9 -
.../devicetree/bindings/arm/arch_timer.txt | 6 +
.../bindings/timer/cortina,gemini-timer.txt | 22 ++
.../devicetree/bindings/timer/renesas,ostm.txt | 30 ++
Documentation/timers/timer_stats.txt | 73 ----
arch/arm/mach-shmobile/Kconfig | 1 +
arch/arm64/include/asm/arch_timer.h | 38 +-
arch/tile/include/asm/Kbuild | 1 -
arch/tile/include/asm/div64.h | 16 +
arch/x86/include/asm/div64.h | 11 +
arch/x86/lib/delay.c | 4 +-
drivers/clocksource/Kconfig | 38 ++
drivers/clocksource/Makefile | 3 +
drivers/clocksource/arm_arch_timer.c | 153 ++++++--
drivers/clocksource/clkevt-probe.c | 56 +++
drivers/clocksource/renesas-ostm.c | 265 +++++++++++++
drivers/clocksource/tcb_clksrc.c | 16 +-
drivers/clocksource/timer-gemini.c | 277 ++++++++++++++
fs/proc/base.c | 4 +-
fs/timerfd.c | 17 +-
include/linux/clockchips.h | 9 +
include/linux/cpumask.h | 7 +-
include/linux/delay.h | 11 +
include/linux/hrtimer.h | 11 -
include/linux/init_task.h | 40 +-
include/linux/math64.h | 26 +-
include/linux/sched.h | 13 +-
include/linux/timer.h | 45 ---
kernel/fork.c | 10 +-
kernel/kthread.c | 1 -
kernel/sched/rt.c | 4 +
kernel/sched/stats.h | 32 +-
kernel/time/Makefile | 1 -
kernel/time/hrtimer.c | 58 +--
kernel/time/tick-broadcast.c | 15 +-
kernel/time/timekeeping.c | 39 +-
kernel/time/timekeeping.h | 2 -
kernel/time/timer.c | 48 +--
kernel/time/timer_list.c | 12 +-
kernel/time/timer_stats.c | 425 ---------------------
kernel/workqueue.c | 2 -
lib/Kconfig.debug | 14 -
lib/timerqueue.c | 3 +-
43 files changed, 1022 insertions(+), 846 deletions(-)
create mode 100644 Documentation/devicetree/bindings/timer/cortina,gemini-timer.txt
create mode 100644 Documentation/devicetree/bindings/timer/renesas,ostm.txt
delete mode 100644 Documentation/timers/timer_stats.txt
create mode 100644 arch/tile/include/asm/div64.h
create mode 100644 drivers/clocksource/clkevt-probe.c
create mode 100644 drivers/clocksource/renesas-ostm.c
create mode 100644 drivers/clocksource/timer-gemini.c
delete mode 100644 kernel/time/timer_stats.c

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index be7c0d9506b1..d8fc55aa9d44 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -549,15 +549,6 @@
loops can be debugged more effectively on production
systems.

- clocksource.arm_arch_timer.fsl-a008585=
- [ARM64]
- Format: <bool>
- Enable/disable the workaround of Freescale/NXP
- erratum A-008585. This can be useful for KVM
- guests, if the guest device tree doesn't show the
- erratum. If unspecified, the workaround is
- enabled based on the device tree.
-
clearcpuid=BITNUM [X86]
Disable CPUID feature X for the kernel. See
arch/x86/include/asm/cpufeatures.h for the valid bit
diff --git a/Documentation/devicetree/bindings/arm/arch_timer.txt b/Documentation/devicetree/bindings/arm/arch_timer.txt
index ad440a2b8051..e926aea1147d 100644
--- a/Documentation/devicetree/bindings/arm/arch_timer.txt
+++ b/Documentation/devicetree/bindings/arm/arch_timer.txt
@@ -31,6 +31,12 @@ to deliver its interrupts via SPIs.
This also affects writes to the tval register, due to the implicit
counter read.

+- hisilicon,erratum-161010101 : A boolean property. Indicates the
+ presence of Hisilicon erratum 161010101, which says that reading the
+ counters is unreliable in some cases, and reads may return a value 32
+ beyond the correct value. This also affects writes to the tval
+ registers, due to the implicit counter read.
+
** Optional properties:

- arm,cpu-registers-not-fw-configured : Firmware does not initialize
diff --git a/Documentation/devicetree/bindings/timer/cortina,gemini-timer.txt b/Documentation/devicetree/bindings/timer/cortina,gemini-timer.txt
new file mode 100644
index 000000000000..16ea1d3b2e9e
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/cortina,gemini-timer.txt
@@ -0,0 +1,22 @@
+Cortina Systems Gemini timer
+
+This timer is embedded in the Cortina Systems Gemini SoCs.
+
+Required properties:
+
+- compatible : Must be "cortina,gemini-timer"
+- reg : Should contain registers location and length
+- interrupts : Should contain the three timer interrupts with
+ flags for rising edge
+- syscon : a phandle to the global Gemini system controller
+
+Example:
+
+timer@43000000 {
+ compatible = "cortina,gemini-timer";
+ reg = <0x43000000 0x1000>;
+ interrupts = <14 IRQ_TYPE_EDGE_RISING>, /* Timer 1 */
+ <15 IRQ_TYPE_EDGE_RISING>, /* Timer 2 */
+ <16 IRQ_TYPE_EDGE_RISING>; /* Timer 3 */
+ syscon = <&syscon>;
+};
diff --git a/Documentation/devicetree/bindings/timer/renesas,ostm.txt b/Documentation/devicetree/bindings/timer/renesas,ostm.txt
new file mode 100644
index 000000000000..be3ae0fdf775
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/renesas,ostm.txt
@@ -0,0 +1,30 @@
+* Renesas OS Timer (OSTM)
+
+The OSTM is a multi-channel 32-bit timer/counter with fixed clock
+source that can operate in either interval count down timer or free-running
+compare match mode.
+
+Channels are independent from each other.
+
+Required Properties:
+
+ - compatible: must be one or more of the following:
+ - "renesas,r7s72100-ostm" for the r7s72100 OSTM
+ - "renesas,ostm" for any OSTM
+ This is a fallback for the above renesas,*-ostm entries
+
+ - reg: base address and length of the register block for a timer channel.
+
+ - interrupts: interrupt specifier for the timer channel.
+
+ - clocks: clock specifier for the timer channel.
+
+Example: R7S72100 (RZ/A1H) OSTM node
+
+ ostm0: timer@fcfec000 {
+ compatible = "renesas,r7s72100-ostm", "renesas,ostm";
+ reg = <0xfcfec000 0x30>;
+ interrupts = <GIC_SPI 102 IRQ_TYPE_EDGE_RISING>;
+ clocks = <&mstp5_clks R7S72100_CLK_OSTM0>;
+ power-domains = <&cpg_clocks>;
+ };
diff --git a/Documentation/timers/timer_stats.txt b/Documentation/timers/timer_stats.txt
deleted file mode 100644
index de835ee97455..000000000000
--- a/Documentation/timers/timer_stats.txt
+++ /dev/null
@@ -1,73 +0,0 @@
-timer_stats - timer usage statistics
-------------------------------------
-
-timer_stats is a debugging facility to make the timer (ab)usage in a Linux
-system visible to kernel and userspace developers. If enabled in the config
-but not used it has almost zero runtime overhead, and a relatively small
-data structure overhead. Even if collection is enabled runtime all the
-locking is per-CPU and lookup is hashed.
-
-timer_stats should be used by kernel and userspace developers to verify that
-their code does not make unduly use of timers. This helps to avoid unnecessary
-wakeups, which should be avoided to optimize power consumption.
-
-It can be enabled by CONFIG_TIMER_STATS in the "Kernel hacking" configuration
-section.
-
-timer_stats collects information about the timer events which are fired in a
-Linux system over a sample period:
-
-- the pid of the task(process) which initialized the timer
-- the name of the process which initialized the timer
-- the function where the timer was initialized
-- the callback function which is associated to the timer
-- the number of events (callbacks)
-
-timer_stats adds an entry to /proc: /proc/timer_stats
-
-This entry is used to control the statistics functionality and to read out the
-sampled information.
-
-The timer_stats functionality is inactive on bootup.
-
-To activate a sample period issue:
-# echo 1 >/proc/timer_stats
-
-To stop a sample period issue:
-# echo 0 >/proc/timer_stats
-
-The statistics can be retrieved by:
-# cat /proc/timer_stats
-
-While sampling is enabled, each readout from /proc/timer_stats will see
-newly updated statistics. Once sampling is disabled, the sampled information
-is kept until a new sample period is started. This allows multiple readouts.
-
-Sample output of /proc/timer_stats:
-
-Timerstats sample period: 3.888770 s
- 12, 0 swapper hrtimer_stop_sched_tick (hrtimer_sched_tick)
- 15, 1 swapper hcd_submit_urb (rh_timer_func)
- 4, 959 kedac schedule_timeout (process_timeout)
- 1, 0 swapper page_writeback_init (wb_timer_fn)
- 28, 0 swapper hrtimer_stop_sched_tick (hrtimer_sched_tick)
- 22, 2948 IRQ 4 tty_flip_buffer_push (delayed_work_timer_fn)
- 3, 3100 bash schedule_timeout (process_timeout)
- 1, 1 swapper queue_delayed_work_on (delayed_work_timer_fn)
- 1, 1 swapper queue_delayed_work_on (delayed_work_timer_fn)
- 1, 1 swapper neigh_table_init_no_netlink (neigh_periodic_timer)
- 1, 2292 ip __netdev_watchdog_up (dev_watchdog)
- 1, 23 events/1 do_cache_clean (delayed_work_timer_fn)
-90 total events, 30.0 events/sec
-
-The first column is the number of events, the second column the pid, the third
-column is the name of the process. The forth column shows the function which
-initialized the timer and in parenthesis the callback function which was
-executed on expiry.
-
- Thomas, Ingo
-
-Added flag to indicate 'deferrable timer' in /proc/timer_stats. A deferrable
-timer will appear as follows
- 10D, 1 swapper queue_delayed_work_on (delayed_work_timer_fn)
-
diff --git a/arch/arm/mach-shmobile/Kconfig b/arch/arm/mach-shmobile/Kconfig
index 2bb4b09f079e..ad7d604ff001 100644
--- a/arch/arm/mach-shmobile/Kconfig
+++ b/arch/arm/mach-shmobile/Kconfig
@@ -57,6 +57,7 @@ config ARCH_R7S72100
select PM
select PM_GENERIC_DOMAINS
select SYS_SUPPORTS_SH_MTU2
+ select RENESAS_OSTM

config ARCH_R8A73A4
bool "R-Mobile APE6 (R8A73A40)"
diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h
index eaa5bbe3fa87..b4b34004a21e 100644
--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -29,41 +29,29 @@

#include <clocksource/arm_arch_timer.h>

-#if IS_ENABLED(CONFIG_FSL_ERRATUM_A008585)
+#if IS_ENABLED(CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND)
extern struct static_key_false arch_timer_read_ool_enabled;
-#define needs_fsl_a008585_workaround() \
+#define needs_unstable_timer_counter_workaround() \
static_branch_unlikely(&arch_timer_read_ool_enabled)
#else
-#define needs_fsl_a008585_workaround() false
+#define needs_unstable_timer_counter_workaround() false
#endif

-u32 __fsl_a008585_read_cntp_tval_el0(void);
-u32 __fsl_a008585_read_cntv_tval_el0(void);
-u64 __fsl_a008585_read_cntvct_el0(void);

-/*
- * The number of retries is an arbitrary value well beyond the highest number
- * of iterations the loop has been observed to take.
- */
-#define __fsl_a008585_read_reg(reg) ({ \
- u64 _old, _new; \
- int _retries = 200; \
- \
- do { \
- _old = read_sysreg(reg); \
- _new = read_sysreg(reg); \
- _retries--; \
- } while (unlikely(_old != _new) && _retries); \
- \
- WARN_ON_ONCE(!_retries); \
- _new; \
-})
+struct arch_timer_erratum_workaround {
+ const char *id; /* Indicate the Erratum ID */
+ u32 (*read_cntp_tval_el0)(void);
+ u32 (*read_cntv_tval_el0)(void);
+ u64 (*read_cntvct_el0)(void);
+};
+
+extern const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround;

#define arch_timer_reg_read_stable(reg) \
({ \
u64 _val; \
- if (needs_fsl_a008585_workaround()) \
- _val = __fsl_a008585_read_##reg(); \
+ if (needs_unstable_timer_counter_workaround()) \
+ _val = timer_unstable_counter_workaround->read_##reg();\
else \
_val = read_sysreg(reg); \
_val; \
diff --git a/arch/tile/include/asm/Kbuild b/arch/tile/include/asm/Kbuild
index 2d1f5638974c..20f2ba6d79be 100644
--- a/arch/tile/include/asm/Kbuild
+++ b/arch/tile/include/asm/Kbuild
@@ -5,7 +5,6 @@ generic-y += bug.h
generic-y += bugs.h
generic-y += clkdev.h
generic-y += cputime.h
-generic-y += div64.h
generic-y += emergency-restart.h
generic-y += errno.h
generic-y += exec.h
diff --git a/arch/tile/include/asm/div64.h b/arch/tile/include/asm/div64.h
new file mode 100644
index 000000000000..9f765cdf09a5
--- /dev/null
+++ b/arch/tile/include/asm/div64.h
@@ -0,0 +1,16 @@
+#ifndef _ASM_TILE_DIV64_H
+#define _ASM_TILE_DIV64_H
+
+#include <linux/types.h>
+
+#ifdef __tilegx__
+static inline u64 mul_u32_u32(u32 a, u32 b)
+{
+ return __insn_mul_lu_lu(a, b);
+}
+#define mul_u32_u32 mul_u32_u32
+#endif
+
+#include <asm-generic/div64.h>
+
+#endif /* _ASM_TILE_DIV64_H */
diff --git a/arch/x86/include/asm/div64.h b/arch/x86/include/asm/div64.h
index ced283ac79df..af95c47d5c9e 100644
--- a/arch/x86/include/asm/div64.h
+++ b/arch/x86/include/asm/div64.h
@@ -59,6 +59,17 @@ static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
}
#define div_u64_rem div_u64_rem

+static inline u64 mul_u32_u32(u32 a, u32 b)
+{
+ u32 high, low;
+
+ asm ("mull %[b]" : "=a" (low), "=d" (high)
+ : [a] "a" (a), [b] "rm" (b) );
+
+ return low | ((u64)high) << 32;
+}
+#define mul_u32_u32 mul_u32_u32
+
#else
# include <asm-generic/div64.h>
#endif /* CONFIG_X86_32 */
diff --git a/arch/x86/lib/delay.c b/arch/x86/lib/delay.c
index 073d1f1a620b..a8e91ae89fb3 100644
--- a/arch/x86/lib/delay.c
+++ b/arch/x86/lib/delay.c
@@ -156,13 +156,13 @@ EXPORT_SYMBOL(__delay);

inline void __const_udelay(unsigned long xloops)
{
+ unsigned long lpj = this_cpu_read(cpu_info.loops_per_jiffy) ? : loops_per_jiffy;
int d0;

xloops *= 4;
asm("mull %%edx"
:"=d" (xloops), "=&a" (d0)
- :"1" (xloops), "0"
- (this_cpu_read(cpu_info.loops_per_jiffy) * (HZ/4)));
+ :"1" (xloops), "0" (lpj * (HZ / 4)));

__delay(++xloops);
}
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 4866f7aa32e6..3356ab821624 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -5,6 +5,10 @@ config CLKSRC_OF
bool
select CLKSRC_PROBE

+config CLKEVT_OF
+ bool
+ select CLKEVT_PROBE
+
config CLKSRC_ACPI
bool
select CLKSRC_PROBE
@@ -12,6 +16,9 @@ config CLKSRC_ACPI
config CLKSRC_PROBE
bool

+config CLKEVT_PROBE
+ bool
+
config CLKSRC_I8253
bool

@@ -60,6 +67,16 @@ config DW_APB_TIMER_OF
select DW_APB_TIMER
select CLKSRC_OF

+config GEMINI_TIMER
+ bool "Cortina Gemini timer driver" if COMPILE_TEST
+ depends on GENERIC_CLOCKEVENTS
+ depends on HAS_IOMEM
+ select CLKSRC_MMIO
+ select CLKSRC_OF
+ select MFD_SYSCON
+ help
+ Enables support for the Gemini timer
+
config ROCKCHIP_TIMER
bool "Rockchip timer driver" if COMPILE_TEST
depends on ARM || ARM64
@@ -325,16 +342,30 @@ config ARM_ARCH_TIMER_EVTSTREAM
This must be disabled for hardware validation purposes to detect any
hardware anomalies of missing events.

+config ARM_ARCH_TIMER_OOL_WORKAROUND
+ bool
+
config FSL_ERRATUM_A008585
bool "Workaround for Freescale/NXP Erratum A-008585"
default y
depends on ARM_ARCH_TIMER && ARM64
+ select ARM_ARCH_TIMER_OOL_WORKAROUND
help
This option enables a workaround for Freescale/NXP Erratum
A-008585 ("ARM generic timer may contain an erroneous
value"). The workaround will only be active if the
fsl,erratum-a008585 property is found in the timer node.

+config HISILICON_ERRATUM_161010101
+ bool "Workaround for Hisilicon Erratum 161010101"
+ default y
+ select ARM_ARCH_TIMER_OOL_WORKAROUND
+ depends on ARM_ARCH_TIMER && ARM64
+ help
+ This option enables a workaround for Hisilicon Erratum
+ 161010101. The workaround will be active if the hisilicon,erratum-161010101
+ property is found in the timer node.
+
config ARM_GLOBAL_TIMER
bool "Support for the ARM global timer" if COMPILE_TEST
select CLKSRC_OF if OF
@@ -467,6 +498,13 @@ config SH_TIMER_MTU2
Timer Pulse Unit 2 (MTU2) hardware available on SoCs from Renesas.
This hardware comes with 16 bit-timer registers.

+config RENESAS_OSTM
+ bool "Renesas OSTM timer driver" if COMPILE_TEST
+ depends on GENERIC_CLOCKEVENTS
+ select CLKSRC_MMIO
+ help
+ Enables the support for the Renesas OSTM.
+
config SH_TIMER_TMU
bool "Renesas TMU timer driver" if COMPILE_TEST
depends on GENERIC_CLOCKEVENTS
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index a14111e1f087..d227d1314f14 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -1,4 +1,5 @@
obj-$(CONFIG_CLKSRC_PROBE) += clksrc-probe.o
+obj-$(CONFIG_CLKEVT_PROBE) += clkevt-probe.o
obj-$(CONFIG_ATMEL_PIT) += timer-atmel-pit.o
obj-$(CONFIG_ATMEL_ST) += timer-atmel-st.o
obj-$(CONFIG_ATMEL_TCB_CLKSRC) += tcb_clksrc.o
@@ -8,6 +9,7 @@ obj-$(CONFIG_CS5535_CLOCK_EVENT_SRC) += cs5535-clockevt.o
obj-$(CONFIG_CLKSRC_JCORE_PIT) += jcore-pit.o
obj-$(CONFIG_SH_TIMER_CMT) += sh_cmt.o
obj-$(CONFIG_SH_TIMER_MTU2) += sh_mtu2.o
+obj-$(CONFIG_RENESAS_OSTM) += renesas-ostm.o
obj-$(CONFIG_SH_TIMER_TMU) += sh_tmu.o
obj-$(CONFIG_EM_TIMER_STI) += em_sti.o
obj-$(CONFIG_CLKBLD_I8253) += i8253.o
@@ -15,6 +17,7 @@ obj-$(CONFIG_CLKSRC_MMIO) += mmio.o
obj-$(CONFIG_DIGICOLOR_TIMER) += timer-digicolor.o
obj-$(CONFIG_DW_APB_TIMER) += dw_apb_timer.o
obj-$(CONFIG_DW_APB_TIMER_OF) += dw_apb_timer_of.o
+obj-$(CONFIG_GEMINI_TIMER) += timer-gemini.o
obj-$(CONFIG_ROCKCHIP_TIMER) += rockchip_timer.o
obj-$(CONFIG_CLKSRC_NOMADIK_MTU) += nomadik-mtu.o
obj-$(CONFIG_CLKSRC_DBX500_PRCMU) += clksrc-dbx500-prcmu.o
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index 4c8c3fb2e8b2..93aa1364376a 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -96,41 +96,107 @@ early_param("clocksource.arm_arch_timer.evtstrm", early_evtstrm_cfg);
*/

#ifdef CONFIG_FSL_ERRATUM_A008585
-DEFINE_STATIC_KEY_FALSE(arch_timer_read_ool_enabled);
-EXPORT_SYMBOL_GPL(arch_timer_read_ool_enabled);
-
-static int fsl_a008585_enable = -1;
-
-static int __init early_fsl_a008585_cfg(char *buf)
+/*
+ * The number of retries is an arbitrary value well beyond the highest number
+ * of iterations the loop has been observed to take.
+ */
+#define __fsl_a008585_read_reg(reg) ({ \
+ u64 _old, _new; \
+ int _retries = 200; \
+ \
+ do { \
+ _old = read_sysreg(reg); \
+ _new = read_sysreg(reg); \
+ _retries--; \
+ } while (unlikely(_old != _new) && _retries); \
+ \
+ WARN_ON_ONCE(!_retries); \
+ _new; \
+})
+
+static u32 notrace fsl_a008585_read_cntp_tval_el0(void)
{
- int ret;
- bool val;
+ return __fsl_a008585_read_reg(cntp_tval_el0);
+}

- ret = strtobool(buf, &val);
- if (ret)
- return ret;
+static u32 notrace fsl_a008585_read_cntv_tval_el0(void)
+{
+ return __fsl_a008585_read_reg(cntv_tval_el0);
+}

- fsl_a008585_enable = val;
- return 0;
+static u64 notrace fsl_a008585_read_cntvct_el0(void)
+{
+ return __fsl_a008585_read_reg(cntvct_el0);
}
-early_param("clocksource.arm_arch_timer.fsl-a008585", early_fsl_a008585_cfg);
+#endif

-u32 __fsl_a008585_read_cntp_tval_el0(void)
+#ifdef CONFIG_HISILICON_ERRATUM_161010101
+/*
+ * Verify whether the value of the second read is larger than the first by
+ * less than 32 is the only way to confirm the value is correct, so clear the
+ * lower 5 bits to check whether the difference is greater than 32 or not.
+ * Theoretically the erratum should not occur more than twice in succession
+ * when reading the system counter, but it is possible that some interrupts
+ * may lead to more than twice read errors, triggering the warning, so setting
+ * the number of retries far beyond the number of iterations the loop has been
+ * observed to take.
+ */
+#define __hisi_161010101_read_reg(reg) ({ \
+ u64 _old, _new; \
+ int _retries = 50; \
+ \
+ do { \
+ _old = read_sysreg(reg); \
+ _new = read_sysreg(reg); \
+ _retries--; \
+ } while (unlikely((_new - _old) >> 5) && _retries); \
+ \
+ WARN_ON_ONCE(!_retries); \
+ _new; \
+})
+
+static u32 notrace hisi_161010101_read_cntp_tval_el0(void)
{
- return __fsl_a008585_read_reg(cntp_tval_el0);
+ return __hisi_161010101_read_reg(cntp_tval_el0);
}

-u32 __fsl_a008585_read_cntv_tval_el0(void)
+static u32 notrace hisi_161010101_read_cntv_tval_el0(void)
{
- return __fsl_a008585_read_reg(cntv_tval_el0);
+ return __hisi_161010101_read_reg(cntv_tval_el0);
}

-u64 __fsl_a008585_read_cntvct_el0(void)
+static u64 notrace hisi_161010101_read_cntvct_el0(void)
{
- return __fsl_a008585_read_reg(cntvct_el0);
+ return __hisi_161010101_read_reg(cntvct_el0);
}
-EXPORT_SYMBOL(__fsl_a008585_read_cntvct_el0);
-#endif /* CONFIG_FSL_ERRATUM_A008585 */
+#endif
+
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
+const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround = NULL;
+EXPORT_SYMBOL_GPL(timer_unstable_counter_workaround);
+
+DEFINE_STATIC_KEY_FALSE(arch_timer_read_ool_enabled);
+EXPORT_SYMBOL_GPL(arch_timer_read_ool_enabled);
+
+static const struct arch_timer_erratum_workaround ool_workarounds[] = {
+#ifdef CONFIG_FSL_ERRATUM_A008585
+ {
+ .id = "fsl,erratum-a008585",
+ .read_cntp_tval_el0 = fsl_a008585_read_cntp_tval_el0,
+ .read_cntv_tval_el0 = fsl_a008585_read_cntv_tval_el0,
+ .read_cntvct_el0 = fsl_a008585_read_cntvct_el0,
+ },
+#endif
+#ifdef CONFIG_HISILICON_ERRATUM_161010101
+ {
+ .id = "hisilicon,erratum-161010101",
+ .read_cntp_tval_el0 = hisi_161010101_read_cntp_tval_el0,
+ .read_cntv_tval_el0 = hisi_161010101_read_cntv_tval_el0,
+ .read_cntvct_el0 = hisi_161010101_read_cntvct_el0,
+ },
+#endif
+};
+#endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */

static __always_inline
void arch_timer_reg_write(int access, enum arch_timer_reg reg, u32 val,
@@ -281,8 +347,8 @@ static __always_inline void set_next_event(const int access, unsigned long evt,
arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
}

-#ifdef CONFIG_FSL_ERRATUM_A008585
-static __always_inline void fsl_a008585_set_next_event(const int access,
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
+static __always_inline void erratum_set_next_event_generic(const int access,
unsigned long evt, struct clock_event_device *clk)
{
unsigned long ctrl;
@@ -300,20 +366,20 @@ static __always_inline void fsl_a008585_set_next_event(const int access,
arch_timer_reg_write(access, ARCH_TIMER_REG_CTRL, ctrl, clk);
}

-static int fsl_a008585_set_next_event_virt(unsigned long evt,
+static int erratum_set_next_event_virt(unsigned long evt,
struct clock_event_device *clk)
{
- fsl_a008585_set_next_event(ARCH_TIMER_VIRT_ACCESS, evt, clk);
+ erratum_set_next_event_generic(ARCH_TIMER_VIRT_ACCESS, evt, clk);
return 0;
}

-static int fsl_a008585_set_next_event_phys(unsigned long evt,
+static int erratum_set_next_event_phys(unsigned long evt,
struct clock_event_device *clk)
{
- fsl_a008585_set_next_event(ARCH_TIMER_PHYS_ACCESS, evt, clk);
+ erratum_set_next_event_generic(ARCH_TIMER_PHYS_ACCESS, evt, clk);
return 0;
}
-#endif /* CONFIG_FSL_ERRATUM_A008585 */
+#endif /* CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND */

static int arch_timer_set_next_event_virt(unsigned long evt,
struct clock_event_device *clk)
@@ -343,16 +409,16 @@ static int arch_timer_set_next_event_phys_mem(unsigned long evt,
return 0;
}

-static void fsl_a008585_set_sne(struct clock_event_device *clk)
+static void erratum_workaround_set_sne(struct clock_event_device *clk)
{
-#ifdef CONFIG_FSL_ERRATUM_A008585
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
if (!static_branch_unlikely(&arch_timer_read_ool_enabled))
return;

if (arch_timer_uses_ppi == VIRT_PPI)
- clk->set_next_event = fsl_a008585_set_next_event_virt;
+ clk->set_next_event = erratum_set_next_event_virt;
else
- clk->set_next_event = fsl_a008585_set_next_event_phys;
+ clk->set_next_event = erratum_set_next_event_phys;
#endif
}

@@ -385,7 +451,7 @@ static void __arch_timer_setup(unsigned type,
BUG();
}

- fsl_a008585_set_sne(clk);
+ erratum_workaround_set_sne(clk);
} else {
clk->features |= CLOCK_EVT_FEAT_DYNIRQ;
clk->name = "arch_mem_timer";
@@ -580,7 +646,7 @@ static struct clocksource clocksource_counter = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};

-static struct cyclecounter cyclecounter = {
+static struct cyclecounter cyclecounter __ro_after_init = {
.read = arch_counter_read_cc,
.mask = CLOCKSOURCE_MASK(56),
};
@@ -605,7 +671,7 @@ static void __init arch_counter_register(unsigned type)

clocksource_counter.archdata.vdso_direct = true;

-#ifdef CONFIG_FSL_ERRATUM_A008585
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
/*
* Don't use the vdso fastpath if errata require using
* the out-of-line counter accessor.
@@ -893,12 +959,15 @@ static int __init arch_timer_of_init(struct device_node *np)

arch_timer_c3stop = !of_property_read_bool(np, "always-on");

-#ifdef CONFIG_FSL_ERRATUM_A008585
- if (fsl_a008585_enable < 0)
- fsl_a008585_enable = of_property_read_bool(np, "fsl,erratum-a008585");
- if (fsl_a008585_enable) {
- static_branch_enable(&arch_timer_read_ool_enabled);
- pr_info("Enabling workaround for FSL erratum A-008585\n");
+#ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND
+ for (i = 0; i < ARRAY_SIZE(ool_workarounds); i++) {
+ if (of_property_read_bool(np, ool_workarounds[i].id)) {
+ timer_unstable_counter_workaround = &ool_workarounds[i];
+ static_branch_enable(&arch_timer_read_ool_enabled);
+ pr_info("arch_timer: Enabling workaround for %s\n",
+ timer_unstable_counter_workaround->id);
+ break;
+ }
}
#endif

diff --git a/drivers/clocksource/clkevt-probe.c b/drivers/clocksource/clkevt-probe.c
new file mode 100644
index 000000000000..8c30fec86094
--- /dev/null
+++ b/drivers/clocksource/clkevt-probe.c
@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2016, Linaro Ltd. All rights reserved.
+ * Daniel Lezcano <daniel.lezcano@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/clockchip.h>
+
+extern struct of_device_id __clkevt_of_table[];
+
+static const struct of_device_id __clkevt_of_table_sentinel
+ __used __section(__clkevt_of_table_end);
+
+int __init clockevent_probe(void)
+{
+ struct device_node *np;
+ const struct of_device_id *match;
+ of_init_fn_1_ret init_func;
+ int ret, clockevents = 0;
+
+ for_each_matching_node_and_match(np, __clkevt_of_table, &match) {
+ if (!of_device_is_available(np))
+ continue;
+
+ init_func = match->data;
+
+ ret = init_func(np);
+ if (ret) {
+ pr_warn("Failed to initialize '%s' (%d)\n",
+ np->name, ret);
+ continue;
+ }
+
+ clockevents++;
+ }
+
+ if (!clockevents) {
+ pr_crit("%s: no matching clockevent found\n", __func__);
+ return -ENODEV;
+ }
+
+ return 0;
+}
diff --git a/drivers/clocksource/renesas-ostm.c b/drivers/clocksource/renesas-ostm.c
new file mode 100644
index 000000000000..c76f57668fb2
--- /dev/null
+++ b/drivers/clocksource/renesas-ostm.c
@@ -0,0 +1,265 @@
+/*
+ * Renesas Timer Support - OSTM
+ *
+ * Copyright (C) 2017 Renesas Electronics America, Inc.
+ * Copyright (C) 2017 Chris Brandt
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+
+/*
+ * The OSTM contains independent channels.
+ * The first OSTM channel probed will be set up as a free running
+ * clocksource. Additionally we will use this clocksource for the system
+ * schedule timer sched_clock().
+ *
+ * The second (or more) channel probed will be set up as an interrupt
+ * driven clock event.
+ */
+
+struct ostm_device {
+ void __iomem *base;
+ unsigned long ticks_per_jiffy;
+ struct clock_event_device ced;
+};
+
+static void __iomem *system_clock; /* For sched_clock() */
+
+/* OSTM REGISTERS */
+#define OSTM_CMP 0x000 /* RW,32 */
+#define OSTM_CNT 0x004 /* R,32 */
+#define OSTM_TE 0x010 /* R,8 */
+#define OSTM_TS 0x014 /* W,8 */
+#define OSTM_TT 0x018 /* W,8 */
+#define OSTM_CTL 0x020 /* RW,8 */
+
+#define TE 0x01
+#define TS 0x01
+#define TT 0x01
+#define CTL_PERIODIC 0x00
+#define CTL_ONESHOT 0x02
+#define CTL_FREERUN 0x02
+
+static struct ostm_device *ced_to_ostm(struct clock_event_device *ced)
+{
+ return container_of(ced, struct ostm_device, ced);
+}
+
+static void ostm_timer_stop(struct ostm_device *ostm)
+{
+ if (readb(ostm->base + OSTM_TE) & TE) {
+ writeb(TT, ostm->base + OSTM_TT);
+
+ /*
+ * Read back the register simply to confirm the write operation
+ * has completed since I/O writes can sometimes get queued by
+ * the bus architecture.
+ */
+ while (readb(ostm->base + OSTM_TE) & TE)
+ ;
+ }
+}
+
+static int __init ostm_init_clksrc(struct ostm_device *ostm, unsigned long rate)
+{
+ /*
+ * irq not used (clock sources don't use interrupts)
+ */
+
+ ostm_timer_stop(ostm);
+
+ writel(0, ostm->base + OSTM_CMP);
+ writeb(CTL_FREERUN, ostm->base + OSTM_CTL);
+ writeb(TS, ostm->base + OSTM_TS);
+
+ return clocksource_mmio_init(ostm->base + OSTM_CNT,
+ "ostm", rate,
+ 300, 32, clocksource_mmio_readl_up);
+}
+
+static u64 notrace ostm_read_sched_clock(void)
+{
+ return readl(system_clock);
+}
+
+static void __init ostm_init_sched_clock(struct ostm_device *ostm,
+ unsigned long rate)
+{
+ system_clock = ostm->base + OSTM_CNT;
+ sched_clock_register(ostm_read_sched_clock, 32, rate);
+}
+
+static int ostm_clock_event_next(unsigned long delta,
+ struct clock_event_device *ced)
+{
+ struct ostm_device *ostm = ced_to_ostm(ced);
+
+ ostm_timer_stop(ostm);
+
+ writel(delta, ostm->base + OSTM_CMP);
+ writeb(CTL_ONESHOT, ostm->base + OSTM_CTL);
+ writeb(TS, ostm->base + OSTM_TS);
+
+ return 0;
+}
+
+static int ostm_shutdown(struct clock_event_device *ced)
+{
+ struct ostm_device *ostm = ced_to_ostm(ced);
+
+ ostm_timer_stop(ostm);
+
+ return 0;
+}
+static int ostm_set_periodic(struct clock_event_device *ced)
+{
+ struct ostm_device *ostm = ced_to_ostm(ced);
+
+ if (clockevent_state_oneshot(ced) || clockevent_state_periodic(ced))
+ ostm_timer_stop(ostm);
+
+ writel(ostm->ticks_per_jiffy - 1, ostm->base + OSTM_CMP);
+ writeb(CTL_PERIODIC, ostm->base + OSTM_CTL);
+ writeb(TS, ostm->base + OSTM_TS);
+
+ return 0;
+}
+
+static int ostm_set_oneshot(struct clock_event_device *ced)
+{
+ struct ostm_device *ostm = ced_to_ostm(ced);
+
+ ostm_timer_stop(ostm);
+
+ return 0;
+}
+
+static irqreturn_t ostm_timer_interrupt(int irq, void *dev_id)
+{
+ struct ostm_device *ostm = dev_id;
+
+ if (clockevent_state_oneshot(&ostm->ced))
+ ostm_timer_stop(ostm);
+
+ /* notify clockevent layer */
+ if (ostm->ced.event_handler)
+ ostm->ced.event_handler(&ostm->ced);
+
+ return IRQ_HANDLED;
+}
+
+static int __init ostm_init_clkevt(struct ostm_device *ostm, int irq,
+ unsigned long rate)
+{
+ struct clock_event_device *ced = &ostm->ced;
+ int ret = -ENXIO;
+
+ ret = request_irq(irq, ostm_timer_interrupt,
+ IRQF_TIMER | IRQF_IRQPOLL,
+ "ostm", ostm);
+ if (ret) {
+ pr_err("ostm: failed to request irq\n");
+ return ret;
+ }
+
+ ced->name = "ostm";
+ ced->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC;
+ ced->set_state_shutdown = ostm_shutdown;
+ ced->set_state_periodic = ostm_set_periodic;
+ ced->set_state_oneshot = ostm_set_oneshot;
+ ced->set_next_event = ostm_clock_event_next;
+ ced->shift = 32;
+ ced->rating = 300;
+ ced->cpumask = cpumask_of(0);
+ clockevents_config_and_register(ced, rate, 0xf, 0xffffffff);
+
+ return 0;
+}
+
+static int __init ostm_init(struct device_node *np)
+{
+ struct ostm_device *ostm;
+ int ret = -EFAULT;
+ struct clk *ostm_clk = NULL;
+ int irq;
+ unsigned long rate;
+
+ ostm = kzalloc(sizeof(*ostm), GFP_KERNEL);
+ if (!ostm)
+ return -ENOMEM;
+
+ ostm->base = of_iomap(np, 0);
+ if (!ostm->base) {
+ pr_err("ostm: failed to remap I/O memory\n");
+ goto err;
+ }
+
+ irq = irq_of_parse_and_map(np, 0);
+ if (irq < 0) {
+ pr_err("ostm: Failed to get irq\n");
+ goto err;
+ }
+
+ ostm_clk = of_clk_get(np, 0);
+ if (IS_ERR(ostm_clk)) {
+ pr_err("ostm: Failed to get clock\n");
+ ostm_clk = NULL;
+ goto err;
+ }
+
+ ret = clk_prepare_enable(ostm_clk);
+ if (ret) {
+ pr_err("ostm: Failed to enable clock\n");
+ goto err;
+ }
+
+ rate = clk_get_rate(ostm_clk);
+ ostm->ticks_per_jiffy = (rate + HZ / 2) / HZ;
+
+ /*
+ * First probed device will be used as system clocksource. Any
+ * additional devices will be used as clock events.
+ */
+ if (!system_clock) {
+ ret = ostm_init_clksrc(ostm, rate);
+
+ if (!ret) {
+ ostm_init_sched_clock(ostm, rate);
+ pr_info("ostm: used for clocksource\n");
+ }
+
+ } else {
+ ret = ostm_init_clkevt(ostm, irq, rate);
+
+ if (!ret)
+ pr_info("ostm: used for clock events\n");
+ }
+
+err:
+ if (ret) {
+ clk_disable_unprepare(ostm_clk);
+ iounmap(ostm->base);
+ kfree(ostm);
+ return ret;
+ }
+
+ return 0;
+}
+
+CLOCKSOURCE_OF_DECLARE(ostm, "renesas,ostm", ostm_init);
diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c
index d4ca9962a759..745844ee973e 100644
--- a/drivers/clocksource/tcb_clksrc.c
+++ b/drivers/clocksource/tcb_clksrc.c
@@ -10,6 +10,7 @@
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/atmel_tc.h>
+#include <linux/sched_clock.h>


/*
@@ -56,11 +57,16 @@ static u64 tc_get_cycles(struct clocksource *cs)
return (upper << 16) | lower;
}

-static u64 tc_get_cycles32(struct clocksource *cs)
+static u32 tc_get_cv32(void)
{
return __raw_readl(tcaddr + ATMEL_TC_REG(0, CV));
}

+static u64 tc_get_cycles32(struct clocksource *cs)
+{
+ return tc_get_cv32();
+}
+
static struct clocksource clksrc = {
.name = "tcb_clksrc",
.rating = 200,
@@ -69,6 +75,11 @@ static struct clocksource clksrc = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};

+static u64 notrace tc_read_sched_clock(void)
+{
+ return tc_get_cv32();
+}
+
#ifdef CONFIG_GENERIC_CLOCKEVENTS

struct tc_clkevt_device {
@@ -339,6 +350,9 @@ static int __init tcb_clksrc_init(void)
clksrc.read = tc_get_cycles32;
/* setup ony channel 0 */
tcb_setup_single_chan(tc, best_divisor_idx);
+
+ /* register sched_clock on chips with single 32 bit counter */
+ sched_clock_register(tc_read_sched_clock, 32, divided_rate);
} else {
/* tclib will give us three clocks no matter what the
* underlying platform supports.
diff --git a/drivers/clocksource/timer-gemini.c b/drivers/clocksource/timer-gemini.c
new file mode 100644
index 000000000000..dda27b7bf1a1
--- /dev/null
+++ b/drivers/clocksource/timer-gemini.c
@@ -0,0 +1,277 @@
+/*
+ * Gemini timer driver
+ * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
+ *
+ * Based on a rewrite of arch/arm/mach-gemini/timer.c:
+ * Copyright (C) 2001-2006 Storlink, Corp.
+ * Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
+ */
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/sched_clock.h>
+
+/*
+ * Relevant registers in the global syscon
+ */
+#define GLOBAL_STATUS 0x04
+#define CPU_AHB_RATIO_MASK (0x3 << 18)
+#define CPU_AHB_1_1 (0x0 << 18)
+#define CPU_AHB_3_2 (0x1 << 18)
+#define CPU_AHB_24_13 (0x2 << 18)
+#define CPU_AHB_2_1 (0x3 << 18)
+#define REG_TO_AHB_SPEED(reg) ((((reg) >> 15) & 0x7) * 10 + 130)
+
+/*
+ * Register definitions for the timers
+ */
+#define TIMER1_COUNT (0x00)
+#define TIMER1_LOAD (0x04)
+#define TIMER1_MATCH1 (0x08)
+#define TIMER1_MATCH2 (0x0c)
+#define TIMER2_COUNT (0x10)
+#define TIMER2_LOAD (0x14)
+#define TIMER2_MATCH1 (0x18)
+#define TIMER2_MATCH2 (0x1c)
+#define TIMER3_COUNT (0x20)
+#define TIMER3_LOAD (0x24)
+#define TIMER3_MATCH1 (0x28)
+#define TIMER3_MATCH2 (0x2c)
+#define TIMER_CR (0x30)
+#define TIMER_INTR_STATE (0x34)
+#define TIMER_INTR_MASK (0x38)
+
+#define TIMER_1_CR_ENABLE (1 << 0)
+#define TIMER_1_CR_CLOCK (1 << 1)
+#define TIMER_1_CR_INT (1 << 2)
+#define TIMER_2_CR_ENABLE (1 << 3)
+#define TIMER_2_CR_CLOCK (1 << 4)
+#define TIMER_2_CR_INT (1 << 5)
+#define TIMER_3_CR_ENABLE (1 << 6)
+#define TIMER_3_CR_CLOCK (1 << 7)
+#define TIMER_3_CR_INT (1 << 8)
+#define TIMER_1_CR_UPDOWN (1 << 9)
+#define TIMER_2_CR_UPDOWN (1 << 10)
+#define TIMER_3_CR_UPDOWN (1 << 11)
+#define TIMER_DEFAULT_FLAGS (TIMER_1_CR_UPDOWN | \
+ TIMER_3_CR_ENABLE | \
+ TIMER_3_CR_UPDOWN)
+
+#define TIMER_1_INT_MATCH1 (1 << 0)
+#define TIMER_1_INT_MATCH2 (1 << 1)
+#define TIMER_1_INT_OVERFLOW (1 << 2)
+#define TIMER_2_INT_MATCH1 (1 << 3)
+#define TIMER_2_INT_MATCH2 (1 << 4)
+#define TIMER_2_INT_OVERFLOW (1 << 5)
+#define TIMER_3_INT_MATCH1 (1 << 6)
+#define TIMER_3_INT_MATCH2 (1 << 7)
+#define TIMER_3_INT_OVERFLOW (1 << 8)
+#define TIMER_INT_ALL_MASK 0x1ff
+
+static unsigned int tick_rate;
+static void __iomem *base;
+
+static u64 notrace gemini_read_sched_clock(void)
+{
+ return readl(base + TIMER3_COUNT);
+}
+
+static int gemini_timer_set_next_event(unsigned long cycles,
+ struct clock_event_device *evt)
+{
+ u32 cr;
+
+ /* Setup the match register */
+ cr = readl(base + TIMER1_COUNT);
+ writel(cr + cycles, base + TIMER1_MATCH1);
+ if (readl(base + TIMER1_COUNT) - cr > cycles)
+ return -ETIME;
+
+ return 0;
+}
+
+static int gemini_timer_shutdown(struct clock_event_device *evt)
+{
+ u32 cr;
+
+ /*
+ * Disable also for oneshot: the set_next() call will arm the timer
+ * instead.
+ */
+ /* Stop timer and interrupt. */
+ cr = readl(base + TIMER_CR);
+ cr &= ~(TIMER_1_CR_ENABLE | TIMER_1_CR_INT);
+ writel(cr, base + TIMER_CR);
+
+ /* Setup counter start from 0 */
+ writel(0, base + TIMER1_COUNT);
+ writel(0, base + TIMER1_LOAD);
+
+ /* enable interrupt */
+ cr = readl(base + TIMER_INTR_MASK);
+ cr &= ~(TIMER_1_INT_OVERFLOW | TIMER_1_INT_MATCH2);
+ cr |= TIMER_1_INT_MATCH1;
+ writel(cr, base + TIMER_INTR_MASK);
+
+ /* start the timer */
+ cr = readl(base + TIMER_CR);
+ cr |= TIMER_1_CR_ENABLE;
+ writel(cr, base + TIMER_CR);
+
+ return 0;
+}
+
+static int gemini_timer_set_periodic(struct clock_event_device *evt)
+{
+ u32 period = DIV_ROUND_CLOSEST(tick_rate, HZ);
+ u32 cr;
+
+ /* Stop timer and interrupt */
+ cr = readl(base + TIMER_CR);
+ cr &= ~(TIMER_1_CR_ENABLE | TIMER_1_CR_INT);
+ writel(cr, base + TIMER_CR);
+
+ /* Setup timer to fire at 1/HT intervals. */
+ cr = 0xffffffff - (period - 1);
+ writel(cr, base + TIMER1_COUNT);
+ writel(cr, base + TIMER1_LOAD);
+
+ /* enable interrupt on overflow */
+ cr = readl(base + TIMER_INTR_MASK);
+ cr &= ~(TIMER_1_INT_MATCH1 | TIMER_1_INT_MATCH2);
+ cr |= TIMER_1_INT_OVERFLOW;
+ writel(cr, base + TIMER_INTR_MASK);
+
+ /* Start the timer */
+ cr = readl(base + TIMER_CR);
+ cr |= TIMER_1_CR_ENABLE;
+ cr |= TIMER_1_CR_INT;
+ writel(cr, base + TIMER_CR);
+
+ return 0;
+}
+
+/* Use TIMER1 as clock event */
+static struct clock_event_device gemini_clockevent = {
+ .name = "TIMER1",
+ /* Reasonably fast and accurate clock event */
+ .rating = 300,
+ .shift = 32,
+ .features = CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_FEAT_ONESHOT,
+ .set_next_event = gemini_timer_set_next_event,
+ .set_state_shutdown = gemini_timer_shutdown,
+ .set_state_periodic = gemini_timer_set_periodic,
+ .set_state_oneshot = gemini_timer_shutdown,
+ .tick_resume = gemini_timer_shutdown,
+};
+
+/*
+ * IRQ handler for the timer
+ */
+static irqreturn_t gemini_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = &gemini_clockevent;
+
+ evt->event_handler(evt);
+ return IRQ_HANDLED;
+}
+
+static struct irqaction gemini_timer_irq = {
+ .name = "Gemini Timer Tick",
+ .flags = IRQF_TIMER,
+ .handler = gemini_timer_interrupt,
+};
+
+static int __init gemini_timer_of_init(struct device_node *np)
+{
+ static struct regmap *map;
+ int irq;
+ int ret;
+ u32 val;
+
+ map = syscon_regmap_lookup_by_phandle(np, "syscon");
+ if (IS_ERR(map)) {
+ pr_err("Can't get regmap for syscon handle");
+ return -ENODEV;
+ }
+ ret = regmap_read(map, GLOBAL_STATUS, &val);
+ if (ret) {
+ pr_err("Can't read syscon status register");
+ return -ENXIO;
+ }
+
+ base = of_iomap(np, 0);
+ if (!base) {
+ pr_err("Can't remap registers");
+ return -ENXIO;
+ }
+ /* IRQ for timer 1 */
+ irq = irq_of_parse_and_map(np, 0);
+ if (irq <= 0) {
+ pr_err("Can't parse IRQ");
+ return -EINVAL;
+ }
+
+ tick_rate = REG_TO_AHB_SPEED(val) * 1000000;
+ printk(KERN_INFO "Bus: %dMHz", tick_rate / 1000000);
+
+ tick_rate /= 6; /* APB bus run AHB*(1/6) */
+
+ switch (val & CPU_AHB_RATIO_MASK) {
+ case CPU_AHB_1_1:
+ printk(KERN_CONT "(1/1)\n");
+ break;
+ case CPU_AHB_3_2:
+ printk(KERN_CONT "(3/2)\n");
+ break;
+ case CPU_AHB_24_13:
+ printk(KERN_CONT "(24/13)\n");
+ break;
+ case CPU_AHB_2_1:
+ printk(KERN_CONT "(2/1)\n");
+ break;
+ }
+
+ /*
+ * Reset the interrupt mask and status
+ */
+ writel(TIMER_INT_ALL_MASK, base + TIMER_INTR_MASK);
+ writel(0, base + TIMER_INTR_STATE);
+ writel(TIMER_DEFAULT_FLAGS, base + TIMER_CR);
+
+ /*
+ * Setup free-running clocksource timer (interrupts
+ * disabled.)
+ */
+ writel(0, base + TIMER3_COUNT);
+ writel(0, base + TIMER3_LOAD);
+ writel(0, base + TIMER3_MATCH1);
+ writel(0, base + TIMER3_MATCH2);
+ clocksource_mmio_init(base + TIMER3_COUNT,
+ "gemini_clocksource", tick_rate,
+ 300, 32, clocksource_mmio_readl_up);
+ sched_clock_register(gemini_read_sched_clock, 32, tick_rate);
+
+ /*
+ * Setup clockevent timer (interrupt-driven.)
+ */
+ writel(0, base + TIMER1_COUNT);
+ writel(0, base + TIMER1_LOAD);
+ writel(0, base + TIMER1_MATCH1);
+ writel(0, base + TIMER1_MATCH2);
+ setup_irq(irq, &gemini_timer_irq);
+ gemini_clockevent.cpumask = cpumask_of(0);
+ clockevents_config_and_register(&gemini_clockevent, tick_rate,
+ 1, 0xffffffff);
+
+ return 0;
+}
+CLOCKSOURCE_OF_DECLARE(nomadik_mtu, "cortina,gemini-timer",
+ gemini_timer_of_init);
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 8e7e61b28f31..03deeac1e835 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2179,7 +2179,7 @@ static const struct file_operations proc_map_files_operations = {
.llseek = generic_file_llseek,
};

-#ifdef CONFIG_CHECKPOINT_RESTORE
+#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
struct timers_private {
struct pid *pid;
struct task_struct *task;
@@ -2936,7 +2936,7 @@ static const struct pid_entry tgid_base_stuff[] = {
REG("projid_map", S_IRUGO|S_IWUSR, proc_projid_map_operations),
REG("setgroups", S_IRUGO|S_IWUSR, proc_setgroups_operations),
#endif
-#ifdef CONFIG_CHECKPOINT_RESTORE
+#if defined(CONFIG_CHECKPOINT_RESTORE) && defined(CONFIG_POSIX_TIMERS)
REG("timers", S_IRUGO, proc_timers_operations),
#endif
REG("timerslack_ns", S_IRUGO|S_IWUGO, proc_pid_set_timerslack_ns_operations),
diff --git a/fs/timerfd.c b/fs/timerfd.c
index c173cc196175..384fa759a563 100644
--- a/fs/timerfd.c
+++ b/fs/timerfd.c
@@ -40,6 +40,7 @@ struct timerfd_ctx {
short unsigned settime_flags; /* to show in fdinfo */
struct rcu_head rcu;
struct list_head clist;
+ spinlock_t cancel_lock;
bool might_cancel;
};

@@ -112,7 +113,7 @@ void timerfd_clock_was_set(void)
rcu_read_unlock();
}

-static void timerfd_remove_cancel(struct timerfd_ctx *ctx)
+static void __timerfd_remove_cancel(struct timerfd_ctx *ctx)
{
if (ctx->might_cancel) {
ctx->might_cancel = false;
@@ -122,6 +123,13 @@ static void timerfd_remove_cancel(struct timerfd_ctx *ctx)
}
}

+static void timerfd_remove_cancel(struct timerfd_ctx *ctx)
+{
+ spin_lock(&ctx->cancel_lock);
+ __timerfd_remove_cancel(ctx);
+ spin_unlock(&ctx->cancel_lock);
+}
+
static bool timerfd_canceled(struct timerfd_ctx *ctx)
{
if (!ctx->might_cancel || ctx->moffs != KTIME_MAX)
@@ -132,6 +140,7 @@ static bool timerfd_canceled(struct timerfd_ctx *ctx)

static void timerfd_setup_cancel(struct timerfd_ctx *ctx, int flags)
{
+ spin_lock(&ctx->cancel_lock);
if ((ctx->clockid == CLOCK_REALTIME ||
ctx->clockid == CLOCK_REALTIME_ALARM) &&
(flags & TFD_TIMER_ABSTIME) && (flags & TFD_TIMER_CANCEL_ON_SET)) {
@@ -141,9 +150,10 @@ static void timerfd_setup_cancel(struct timerfd_ctx *ctx, int flags)
list_add_rcu(&ctx->clist, &cancel_list);
spin_unlock(&cancel_lock);
}
- } else if (ctx->might_cancel) {
- timerfd_remove_cancel(ctx);
+ } else {
+ __timerfd_remove_cancel(ctx);
}
+ spin_unlock(&ctx->cancel_lock);
}

static ktime_t timerfd_get_remaining(struct timerfd_ctx *ctx)
@@ -400,6 +410,7 @@ SYSCALL_DEFINE2(timerfd_create, int, clockid, int, flags)
return -ENOMEM;

init_waitqueue_head(&ctx->wqh);
+ spin_lock_init(&ctx->cancel_lock);
ctx->clockid = clockid;

if (isalarm(ctx))
diff --git a/include/linux/clockchips.h b/include/linux/clockchips.h
index 0d442e34c349..5d3053c34fb3 100644
--- a/include/linux/clockchips.h
+++ b/include/linux/clockchips.h
@@ -224,4 +224,13 @@ static inline void tick_setup_hrtimer_broadcast(void) { }

#endif /* !CONFIG_GENERIC_CLOCKEVENTS */

+#define CLOCKEVENT_OF_DECLARE(name, compat, fn) \
+ OF_DECLARE_1_RET(clkevt, name, compat, fn)
+
+#ifdef CONFIG_CLKEVT_PROBE
+extern int clockevent_probe(void);
+#els
+static inline int clockevent_probe(void) { return 0; }
+#endif
+
#endif /* _LINUX_CLOCKCHIPS_H */
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index c717f5ea88cb..23c1a6d09ec5 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -649,11 +649,15 @@ static inline size_t cpumask_size(void)
* used. Please use this_cpu_cpumask_var_t in those cases. The direct use
* of this_cpu_ptr() or this_cpu_read() will lead to failures when the
* other type of cpumask_var_t implementation is configured.
+ *
+ * Please also note that __cpumask_var_read_mostly can be used to declare
+ * a cpumask_var_t variable itself (not its content) as read mostly.
*/
#ifdef CONFIG_CPUMASK_OFFSTACK
typedef struct cpumask *cpumask_var_t;

-#define this_cpu_cpumask_var_ptr(x) this_cpu_read(x)
+#define this_cpu_cpumask_var_ptr(x) this_cpu_read(x)
+#define __cpumask_var_read_mostly __read_mostly

bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
@@ -667,6 +671,7 @@ void free_bootmem_cpumask_var(cpumask_var_t mask);
typedef struct cpumask cpumask_var_t[1];

#define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x)
+#define __cpumask_var_read_mostly

static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
{
diff --git a/include/linux/delay.h b/include/linux/delay.h
index a6ecb34cf547..2ecb3c46b20a 100644
--- a/include/linux/delay.h
+++ b/include/linux/delay.h
@@ -5,6 +5,17 @@
* Copyright (C) 1993 Linus Torvalds
*
* Delay routines, using a pre-computed "loops_per_jiffy" value.
+ *
+ * Please note that ndelay(), udelay() and mdelay() may return early for
+ * several reasons:
+ * 1. computed loops_per_jiffy too low (due to the time taken to
+ * execute the timer interrupt.)
+ * 2. cache behaviour affecting the time it takes to execute the
+ * loop function.
+ * 3. CPU clock rate changes.
+ *
+ * Please see this thread:
+ * http://lists.openwall.net/linux-kernel/2011/01/09/56
*/

#include <linux/kernel.h>
diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index cdab81ba29f8..e52b427223ba 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -88,12 +88,6 @@ enum hrtimer_restart {
* @base: pointer to the timer base (per cpu and per clock)
* @state: state information (See bit values above)
* @is_rel: Set if the timer was armed relative
- * @start_pid: timer statistics field to store the pid of the task which
- * started the timer
- * @start_site: timer statistics field to store the site where the timer
- * was started
- * @start_comm: timer statistics field to store the name of the process which
- * started the timer
*
* The hrtimer structure must be initialized by hrtimer_init()
*/
@@ -104,11 +98,6 @@ struct hrtimer {
struct hrtimer_clock_base *base;
u8 state;
u8 is_rel;
-#ifdef CONFIG_TIMER_STATS
- int start_pid;
- void *start_site;
- char start_comm[16];
-#endif
};

/**
diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index 325f649d77ff..3a85d61f7614 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -42,6 +42,27 @@ extern struct fs_struct init_fs;
#define INIT_PREV_CPUTIME(x)
#endif

+#ifdef CONFIG_POSIX_TIMERS
+#define INIT_POSIX_TIMERS(s) \
+ .posix_timers = LIST_HEAD_INIT(s.posix_timers),
+#define INIT_CPU_TIMERS(s) \
+ .cpu_timers = { \
+ LIST_HEAD_INIT(s.cpu_timers[0]), \
+ LIST_HEAD_INIT(s.cpu_timers[1]), \
+ LIST_HEAD_INIT(s.cpu_timers[2]), \
+ },
+#define INIT_CPUTIMER(s) \
+ .cputimer = { \
+ .cputime_atomic = INIT_CPUTIME_ATOMIC, \
+ .running = false, \
+ .checking_timer = false, \
+ },
+#else
+#define INIT_POSIX_TIMERS(s)
+#define INIT_CPU_TIMERS(s)
+#define INIT_CPUTIMER(s)
+#endif
+
#define INIT_SIGNALS(sig) { \
.nr_threads = 1, \
.thread_head = LIST_HEAD_INIT(init_task.thread_node), \
@@ -49,14 +70,10 @@ extern struct fs_struct init_fs;
.shared_pending = { \
.list = LIST_HEAD_INIT(sig.shared_pending.list), \
.signal = {{0}}}, \
- .posix_timers = LIST_HEAD_INIT(sig.posix_timers), \
- .cpu_timers = INIT_CPU_TIMERS(sig.cpu_timers), \
+ INIT_POSIX_TIMERS(sig) \
+ INIT_CPU_TIMERS(sig) \
.rlim = INIT_RLIMITS, \
- .cputimer = { \
- .cputime_atomic = INIT_CPUTIME_ATOMIC, \
- .running = false, \
- .checking_timer = false, \
- }, \
+ INIT_CPUTIMER(sig) \
INIT_PREV_CPUTIME(sig) \
.cred_guard_mutex = \
__MUTEX_INITIALIZER(sig.cred_guard_mutex), \
@@ -247,7 +264,7 @@ extern struct task_group root_task_group;
.blocked = {{0}}, \
.alloc_lock = __SPIN_LOCK_UNLOCKED(tsk.alloc_lock), \
.journal_info = NULL, \
- .cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \
+ INIT_CPU_TIMERS(tsk) \
.pi_lock = __RAW_SPIN_LOCK_UNLOCKED(tsk.pi_lock), \
.timer_slack_ns = 50000, /* 50 usec default slack */ \
.pids = { \
@@ -274,13 +291,6 @@ extern struct task_group root_task_group;
}


-#define INIT_CPU_TIMERS(cpu_timers) \
-{ \
- LIST_HEAD_INIT(cpu_timers[0]), \
- LIST_HEAD_INIT(cpu_timers[1]), \
- LIST_HEAD_INIT(cpu_timers[2]), \
-}
-
/* Attach to the init_task data structure for proper alignment */
#define __init_task_data __attribute__((__section__(".data..init_task")))

diff --git a/include/linux/math64.h b/include/linux/math64.h
index 6e8b5b270ffe..80690c96c734 100644
--- a/include/linux/math64.h
+++ b/include/linux/math64.h
@@ -133,6 +133,16 @@ __iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
return ret;
}

+#ifndef mul_u32_u32
+/*
+ * Many a GCC version messes this up and generates a 64x64 mult :-(
+ */
+static inline u64 mul_u32_u32(u32 a, u32 b)
+{
+ return (u64)a * b;
+}
+#endif
+
#if defined(CONFIG_ARCH_SUPPORTS_INT128) && defined(__SIZEOF_INT128__)

#ifndef mul_u64_u32_shr
@@ -160,9 +170,9 @@ static inline u64 mul_u64_u32_shr(u64 a, u32 mul, unsigned int shift)
al = a;
ah = a >> 32;

- ret = ((u64)al * mul) >> shift;
+ ret = mul_u32_u32(al, mul) >> shift;
if (ah)
- ret += ((u64)ah * mul) << (32 - shift);
+ ret += mul_u32_u32(ah, mul) << (32 - shift);

return ret;
}
@@ -186,10 +196,10 @@ static inline u64 mul_u64_u64_shr(u64 a, u64 b, unsigned int shift)
a0.ll = a;
b0.ll = b;

- rl.ll = (u64)a0.l.low * b0.l.low;
- rm.ll = (u64)a0.l.low * b0.l.high;
- rn.ll = (u64)a0.l.high * b0.l.low;
- rh.ll = (u64)a0.l.high * b0.l.high;
+ rl.ll = mul_u32_u32(a0.l.low, b0.l.low);
+ rm.ll = mul_u32_u32(a0.l.low, b0.l.high);
+ rn.ll = mul_u32_u32(a0.l.high, b0.l.low);
+ rh.ll = mul_u32_u32(a0.l.high, b0.l.high);

/*
* Each of these lines computes a 64-bit intermediate result into "c",
@@ -229,8 +239,8 @@ static inline u64 mul_u64_u32_div(u64 a, u32 mul, u32 divisor)
} u, rl, rh;

u.ll = a;
- rl.ll = (u64)u.l.low * mul;
- rh.ll = (u64)u.l.high * mul + rl.l.high;
+ rl.ll = mul_u32_u32(u.l.low, mul);
+ rh.ll = mul_u32_u32(u.l.high, mul) + rl.l.high;

/* Bits 32-63 of the result will be in rh.l.low. */
rl.l.high = do_div(rh.ll, divisor);
diff --git a/include/linux/sched.h b/include/linux/sched.h
index ad3ec9ec61f7..6e4782eae076 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -734,13 +734,14 @@ struct signal_struct {
unsigned int is_child_subreaper:1;
unsigned int has_child_subreaper:1;

+#ifdef CONFIG_POSIX_TIMERS
+
/* POSIX.1b Interval Timers */
int posix_timer_id;
struct list_head posix_timers;

/* ITIMER_REAL timer for the process */
struct hrtimer real_timer;
- struct pid *leader_pid;
ktime_t it_real_incr;

/*
@@ -759,12 +760,16 @@ struct signal_struct {
/* Earliest-expiration cache. */
struct task_cputime cputime_expires;

+ struct list_head cpu_timers[3];
+
+#endif
+
+ struct pid *leader_pid;
+
#ifdef CONFIG_NO_HZ_FULL
atomic_t tick_dep_mask;
#endif

- struct list_head cpu_timers[3];
-
struct pid *tty_old_pgrp;

/* boolean value for session group leader */
@@ -1691,8 +1696,10 @@ struct task_struct {
/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
unsigned long min_flt, maj_flt;

+#ifdef CONFIG_POSIX_TIMERS
struct task_cputime cputime_expires;
struct list_head cpu_timers[3];
+#endif

/* process credentials */
const struct cred __rcu *ptracer_cred; /* Tracer's credentials at attach */
diff --git a/include/linux/timer.h b/include/linux/timer.h
index 51d601f192d4..5a209b84fd9e 100644
--- a/include/linux/timer.h
+++ b/include/linux/timer.h
@@ -20,11 +20,6 @@ struct timer_list {
unsigned long data;
u32 flags;

-#ifdef CONFIG_TIMER_STATS
- int start_pid;
- void *start_site;
- char start_comm[16];
-#endif
#ifdef CONFIG_LOCKDEP
struct lockdep_map lockdep_map;
#endif
@@ -197,46 +192,6 @@ extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);
*/
#define NEXT_TIMER_MAX_DELTA ((1UL << 30) - 1)

-/*
- * Timer-statistics info:
- */
-#ifdef CONFIG_TIMER_STATS
-
-extern int timer_stats_active;
-
-extern void init_timer_stats(void);
-
-extern void timer_stats_update_stats(void *timer, pid_t pid, void *startf,
- void *timerf, char *comm, u32 flags);
-
-extern void __timer_stats_timer_set_start_info(struct timer_list *timer,
- void *addr);
-
-static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
-{
- if (likely(!timer_stats_active))
- return;
- __timer_stats_timer_set_start_info(timer, __builtin_return_address(0));
-}
-
-static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
-{
- timer->start_site = NULL;
-}
-#else
-static inline void init_timer_stats(void)
-{
-}
-
-static inline void timer_stats_timer_set_start_info(struct timer_list *timer)
-{
-}
-
-static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
-{
-}
-#endif
-
extern void add_timer(struct timer_list *timer);

extern int try_to_del_timer_sync(struct timer_list *timer);
diff --git a/kernel/fork.c b/kernel/fork.c
index 11c5c8ab827c..105c6676d93b 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1304,6 +1304,7 @@ void __cleanup_sighand(struct sighand_struct *sighand)
}
}

+#ifdef CONFIG_POSIX_TIMERS
/*
* Initialize POSIX timer handling for a thread group.
*/
@@ -1322,6 +1323,9 @@ static void posix_cpu_timers_init_group(struct signal_struct *sig)
INIT_LIST_HEAD(&sig->cpu_timers[1]);
INIT_LIST_HEAD(&sig->cpu_timers[2]);
}
+#else
+static inline void posix_cpu_timers_init_group(struct signal_struct *sig) { }
+#endif

static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
{
@@ -1346,11 +1350,11 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk)
init_waitqueue_head(&sig->wait_chldexit);
sig->curr_target = tsk;
init_sigpending(&sig->shared_pending);
- INIT_LIST_HEAD(&sig->posix_timers);
seqlock_init(&sig->stats_lock);
prev_cputime_init(&sig->prev_cputime);

#ifdef CONFIG_POSIX_TIMERS
+ INIT_LIST_HEAD(&sig->posix_timers);
hrtimer_init(&sig->real_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
sig->real_timer.function = it_real_fn;
#endif
@@ -1425,6 +1429,7 @@ static void rt_mutex_init_task(struct task_struct *p)
#endif
}

+#ifdef CONFIG_POSIX_TIMERS
/*
* Initialize POSIX timer handling for a single task.
*/
@@ -1437,6 +1442,9 @@ static void posix_cpu_timers_init(struct task_struct *tsk)
INIT_LIST_HEAD(&tsk->cpu_timers[1]);
INIT_LIST_HEAD(&tsk->cpu_timers[2]);
}
+#else
+static inline void posix_cpu_timers_init(struct task_struct *tsk) { }
+#endif

static inline void
init_task_pid(struct task_struct *task, enum pid_type type, struct pid *pid)
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 2318fba86277..8461a4372e8a 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -850,7 +850,6 @@ void __kthread_queue_delayed_work(struct kthread_worker *worker,

list_add(&work->node, &worker->delayed_work_list);
work->worker = worker;
- timer_stats_timer_set_start_info(&dwork->timer);
timer->expires = jiffies + delay;
add_timer(timer);
}
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 2516b8df6dbb..a688a8206727 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -2246,6 +2246,7 @@ prio_changed_rt(struct rq *rq, struct task_struct *p, int oldprio)
}
}

+#ifdef CONFIG_POSIX_TIMERS
static void watchdog(struct rq *rq, struct task_struct *p)
{
unsigned long soft, hard;
@@ -2267,6 +2268,9 @@ static void watchdog(struct rq *rq, struct task_struct *p)
p->cputime_expires.sched_exp = p->se.sum_exec_runtime;
}
}
+#else
+static inline void watchdog(struct rq *rq, struct task_struct *p) { }
+#endif

static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
{
diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h
index 34659a853505..c69a9870ab79 100644
--- a/kernel/sched/stats.h
+++ b/kernel/sched/stats.h
@@ -172,18 +172,19 @@ sched_info_switch(struct rq *rq,
*/

/**
- * cputimer_running - return true if cputimer is running
+ * get_running_cputimer - return &tsk->signal->cputimer if cputimer is running
*
* @tsk: Pointer to target task.
*/
-static inline bool cputimer_running(struct task_struct *tsk)
-
+#ifdef CONFIG_POSIX_TIMERS
+static inline
+struct thread_group_cputimer *get_running_cputimer(struct task_struct *tsk)
{
struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;

/* Check if cputimer isn't running. This is accessed without locking. */
if (!READ_ONCE(cputimer->running))
- return false;
+ return NULL;

/*
* After we flush the task's sum_exec_runtime to sig->sum_sched_runtime
@@ -200,10 +201,17 @@ static inline bool cputimer_running(struct task_struct *tsk)
* clock delta is behind the expiring timer value.
*/
if (unlikely(!tsk->sighand))
- return false;
+ return NULL;

- return true;
+ return cputimer;
+}
+#else
+static inline
+struct thread_group_cputimer *get_running_cputimer(struct task_struct *tsk)
+{
+ return NULL;
}
+#endif

/**
* account_group_user_time - Maintain utime for a thread group.
@@ -218,9 +226,9 @@ static inline bool cputimer_running(struct task_struct *tsk)
static inline void account_group_user_time(struct task_struct *tsk,
cputime_t cputime)
{
- struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+ struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);

- if (!cputimer_running(tsk))
+ if (!cputimer)
return;

atomic64_add(cputime, &cputimer->cputime_atomic.utime);
@@ -239,9 +247,9 @@ static inline void account_group_user_time(struct task_struct *tsk,
static inline void account_group_system_time(struct task_struct *tsk,
cputime_t cputime)
{
- struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+ struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);

- if (!cputimer_running(tsk))
+ if (!cputimer)
return;

atomic64_add(cputime, &cputimer->cputime_atomic.stime);
@@ -260,9 +268,9 @@ static inline void account_group_system_time(struct task_struct *tsk,
static inline void account_group_exec_runtime(struct task_struct *tsk,
unsigned long long ns)
{
- struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+ struct thread_group_cputimer *cputimer = get_running_cputimer(tsk);

- if (!cputimer_running(tsk))
+ if (!cputimer)
return;

atomic64_add(ns, &cputimer->cputime_atomic.sum_exec_runtime);
diff --git a/kernel/time/Makefile b/kernel/time/Makefile
index 976840d29a71..938dbf33ef49 100644
--- a/kernel/time/Makefile
+++ b/kernel/time/Makefile
@@ -15,6 +15,5 @@ ifeq ($(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST),y)
endif
obj-$(CONFIG_GENERIC_SCHED_CLOCK) += sched_clock.o
obj-$(CONFIG_TICK_ONESHOT) += tick-oneshot.o tick-sched.o
-obj-$(CONFIG_TIMER_STATS) += timer_stats.o
obj-$(CONFIG_DEBUG_FS) += timekeeping_debug.o
obj-$(CONFIG_TEST_UDELAY) += test_udelay.o
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index c6ecedd3b839..8e11d8d9f419 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -94,17 +94,15 @@ DEFINE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases) =
};

static const int hrtimer_clock_to_base_table[MAX_CLOCKS] = {
+ /* Make sure we catch unsupported clockids */
+ [0 ... MAX_CLOCKS - 1] = HRTIMER_MAX_CLOCK_BASES,
+
[CLOCK_REALTIME] = HRTIMER_BASE_REALTIME,
[CLOCK_MONOTONIC] = HRTIMER_BASE_MONOTONIC,
[CLOCK_BOOTTIME] = HRTIMER_BASE_BOOTTIME,
[CLOCK_TAI] = HRTIMER_BASE_TAI,
};

-static inline int hrtimer_clockid_to_base(clockid_t clock_id)
-{
- return hrtimer_clock_to_base_table[clock_id];
-}
-
/*
* Functions and macros which are different for UP/SMP systems are kept in a
* single place
@@ -766,34 +764,6 @@ void hrtimers_resume(void)
clock_was_set_delayed();
}

-static inline void timer_stats_hrtimer_set_start_info(struct hrtimer *timer)
-{
-#ifdef CONFIG_TIMER_STATS
- if (timer->start_site)
- return;
- timer->start_site = __builtin_return_address(0);
- memcpy(timer->start_comm, current->comm, TASK_COMM_LEN);
- timer->start_pid = current->pid;
-#endif
-}
-
-static inline void timer_stats_hrtimer_clear_start_info(struct hrtimer *timer)
-{
-#ifdef CONFIG_TIMER_STATS
- timer->start_site = NULL;
-#endif
-}
-
-static inline void timer_stats_account_hrtimer(struct hrtimer *timer)
-{
-#ifdef CONFIG_TIMER_STATS
- if (likely(!timer_stats_active))
- return;
- timer_stats_update_stats(timer, timer->start_pid, timer->start_site,
- timer->function, timer->start_comm, 0);
-#endif
-}
-
/*
* Counterpart to lock_hrtimer_base above:
*/
@@ -932,7 +902,6 @@ remove_hrtimer(struct hrtimer *timer, struct hrtimer_clock_base *base, bool rest
* rare case and less expensive than a smp call.
*/
debug_deactivate(timer);
- timer_stats_hrtimer_clear_start_info(timer);
reprogram = base->cpu_base == this_cpu_ptr(&hrtimer_bases);

if (!restart)
@@ -990,8 +959,6 @@ void hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
/* Switch the timer base, if necessary: */
new_base = switch_hrtimer_base(timer, base, mode & HRTIMER_MODE_PINNED);

- timer_stats_hrtimer_set_start_info(timer);
-
leftmost = enqueue_hrtimer(timer, new_base);
if (!leftmost)
goto unlock;
@@ -1112,6 +1079,18 @@ u64 hrtimer_get_next_event(void)
}
#endif

+static inline int hrtimer_clockid_to_base(clockid_t clock_id)
+{
+ if (likely(clock_id < MAX_CLOCKS)) {
+ int base = hrtimer_clock_to_base_table[clock_id];
+
+ if (likely(base != HRTIMER_MAX_CLOCK_BASES))
+ return base;
+ }
+ WARN(1, "Invalid clockid %d. Using MONOTONIC\n", clock_id);
+ return HRTIMER_BASE_MONOTONIC;
+}
+
static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
enum hrtimer_mode mode)
{
@@ -1128,12 +1107,6 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
base = hrtimer_clockid_to_base(clock_id);
timer->base = &cpu_base->clock_base[base];
timerqueue_init(&timer->node);
-
-#ifdef CONFIG_TIMER_STATS
- timer->start_site = NULL;
- timer->start_pid = -1;
- memset(timer->start_comm, 0, TASK_COMM_LEN);
-#endif
}

/**
@@ -1217,7 +1190,6 @@ static void __run_hrtimer(struct hrtimer_cpu_base *cpu_base,
raw_write_seqcount_barrier(&cpu_base->seq);

__remove_hrtimer(timer, base, HRTIMER_STATE_INACTIVE, 0);
- timer_stats_account_hrtimer(timer);
fn = timer->function;

/*
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 3109204c87cc..244c93544150 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -29,12 +29,13 @@
*/

static struct tick_device tick_broadcast_device;
-static cpumask_var_t tick_broadcast_mask;
-static cpumask_var_t tick_broadcast_on;
-static cpumask_var_t tmpmask;
-static DEFINE_RAW_SPINLOCK(tick_broadcast_lock);
+static cpumask_var_t tick_broadcast_mask __cpumask_var_read_mostly;
+static cpumask_var_t tick_broadcast_on __cpumask_var_read_mostly;
+static cpumask_var_t tmpmask __cpumask_var_read_mostly;
static int tick_broadcast_forced;

+static __cacheline_aligned_in_smp DEFINE_RAW_SPINLOCK(tick_broadcast_lock);
+
#ifdef CONFIG_TICK_ONESHOT
static void tick_broadcast_clear_oneshot(int cpu);
static void tick_resume_broadcast_oneshot(struct clock_event_device *bc);
@@ -517,9 +518,9 @@ void tick_resume_broadcast(void)

#ifdef CONFIG_TICK_ONESHOT

-static cpumask_var_t tick_broadcast_oneshot_mask;
-static cpumask_var_t tick_broadcast_pending_mask;
-static cpumask_var_t tick_broadcast_force_mask;
+static cpumask_var_t tick_broadcast_oneshot_mask __cpumask_var_read_mostly;
+static cpumask_var_t tick_broadcast_pending_mask __cpumask_var_read_mostly;
+static cpumask_var_t tick_broadcast_force_mask __cpumask_var_read_mostly;

/*
* Exposed for debugging: see timer_list.c
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index db087d7e106d..95b258dd75db 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1275,27 +1275,8 @@ int timekeeping_inject_offset(struct timespec *ts)
}
EXPORT_SYMBOL(timekeeping_inject_offset);

-
-/**
- * timekeeping_get_tai_offset - Returns current TAI offset from UTC
- *
- */
-s32 timekeeping_get_tai_offset(void)
-{
- struct timekeeper *tk = &tk_core.timekeeper;
- unsigned int seq;
- s32 ret;
-
- do {
- seq = read_seqcount_begin(&tk_core.seq);
- ret = tk->tai_offset;
- } while (read_seqcount_retry(&tk_core.seq, seq));
-
- return ret;
-}
-
/**
- * __timekeeping_set_tai_offset - Lock free worker function
+ * __timekeeping_set_tai_offset - Sets the TAI offset from UTC and monotonic
*
*/
static void __timekeeping_set_tai_offset(struct timekeeper *tk, s32 tai_offset)
@@ -1305,24 +1286,6 @@ static void __timekeeping_set_tai_offset(struct timekeeper *tk, s32 tai_offset)
}

/**
- * timekeeping_set_tai_offset - Sets the current TAI offset from UTC
- *
- */
-void timekeeping_set_tai_offset(s32 tai_offset)
-{
- struct timekeeper *tk = &tk_core.timekeeper;
- unsigned long flags;
-
- raw_spin_lock_irqsave(&timekeeper_lock, flags);
- write_seqcount_begin(&tk_core.seq);
- __timekeeping_set_tai_offset(tk, tai_offset);
- timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
- write_seqcount_end(&tk_core.seq);
- raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
- clock_was_set();
-}
-
-/**
* change_clocksource - Swaps clocksources if a new one is available
*
* Accumulates current time interval and initializes new clocksource
diff --git a/kernel/time/timekeeping.h b/kernel/time/timekeeping.h
index 704f595ce83f..d0914676d4c5 100644
--- a/kernel/time/timekeeping.h
+++ b/kernel/time/timekeeping.h
@@ -11,8 +11,6 @@ extern ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq,
extern int timekeeping_valid_for_hres(void);
extern u64 timekeeping_max_deferment(void);
extern int timekeeping_inject_offset(struct timespec *ts);
-extern s32 timekeeping_get_tai_offset(void);
-extern void timekeeping_set_tai_offset(s32 tai_offset);
extern int timekeeping_suspend(void);
extern void timekeeping_resume(void);

diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index ec33a6933eae..82a6bfa0c307 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -571,38 +571,6 @@ internal_add_timer(struct timer_base *base, struct timer_list *timer)
trigger_dyntick_cpu(base, timer);
}

-#ifdef CONFIG_TIMER_STATS
-void __timer_stats_timer_set_start_info(struct timer_list *timer, void *addr)
-{
- if (timer->start_site)
- return;
-
- timer->start_site = addr;
- memcpy(timer->start_comm, current->comm, TASK_COMM_LEN);
- timer->start_pid = current->pid;
-}
-
-static void timer_stats_account_timer(struct timer_list *timer)
-{
- void *site;
-
- /*
- * start_site can be concurrently reset by
- * timer_stats_timer_clear_start_info()
- */
- site = READ_ONCE(timer->start_site);
- if (likely(!site))
- return;
-
- timer_stats_update_stats(timer, timer->start_pid, site,
- timer->function, timer->start_comm,
- timer->flags);
-}
-
-#else
-static void timer_stats_account_timer(struct timer_list *timer) {}
-#endif
-
#ifdef CONFIG_DEBUG_OBJECTS_TIMERS

static struct debug_obj_descr timer_debug_descr;
@@ -789,11 +757,6 @@ static void do_init_timer(struct timer_list *timer, unsigned int flags,
{
timer->entry.pprev = NULL;
timer->flags = flags | raw_smp_processor_id();
-#ifdef CONFIG_TIMER_STATS
- timer->start_site = NULL;
- timer->start_pid = -1;
- memset(timer->start_comm, 0, TASK_COMM_LEN);
-#endif
lockdep_init_map(&timer->lockdep_map, name, key, 0);
}

@@ -1001,8 +964,6 @@ __mod_timer(struct timer_list *timer, unsigned long expires, bool pending_only)
base = lock_timer_base(timer, &flags);
}

- timer_stats_timer_set_start_info(timer);
-
ret = detach_if_pending(timer, base, false);
if (!ret && pending_only)
goto out_unlock;
@@ -1130,7 +1091,6 @@ void add_timer_on(struct timer_list *timer, int cpu)
struct timer_base *new_base, *base;
unsigned long flags;

- timer_stats_timer_set_start_info(timer);
BUG_ON(timer_pending(timer) || !timer->function);

new_base = get_timer_cpu_base(timer->flags, cpu);
@@ -1176,7 +1136,6 @@ int del_timer(struct timer_list *timer)

debug_assert_init(timer);

- timer_stats_timer_clear_start_info(timer);
if (timer_pending(timer)) {
base = lock_timer_base(timer, &flags);
ret = detach_if_pending(timer, base, true);
@@ -1204,10 +1163,9 @@ int try_to_del_timer_sync(struct timer_list *timer)

base = lock_timer_base(timer, &flags);

- if (base->running_timer != timer) {
- timer_stats_timer_clear_start_info(timer);
+ if (base->running_timer != timer)
ret = detach_if_pending(timer, base, true);
- }
+
spin_unlock_irqrestore(&base->lock, flags);

return ret;
@@ -1331,7 +1289,6 @@ static void expire_timers(struct timer_base *base, struct hlist_head *head)
unsigned long data;

timer = hlist_entry(head->first, struct timer_list, entry);
- timer_stats_account_timer(timer);

base->running_timer = timer;
detach_timer(timer, true);
@@ -1868,7 +1825,6 @@ static void __init init_timer_cpus(void)
void __init init_timers(void)
{
init_timer_cpus();
- init_timer_stats();
open_softirq(TIMER_SOFTIRQ, run_timer_softirq);
}

diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c
index afe6cd1944fc..ff8d5c13d04b 100644
--- a/kernel/time/timer_list.c
+++ b/kernel/time/timer_list.c
@@ -62,21 +62,11 @@ static void
print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer,
int idx, u64 now)
{
-#ifdef CONFIG_TIMER_STATS
- char tmp[TASK_COMM_LEN + 1];
-#endif
SEQ_printf(m, " #%d: ", idx);
print_name_offset(m, taddr);
SEQ_printf(m, ", ");
print_name_offset(m, timer->function);
SEQ_printf(m, ", S:%02x", timer->state);
-#ifdef CONFIG_TIMER_STATS
- SEQ_printf(m, ", ");
- print_name_offset(m, timer->start_site);
- memcpy(tmp, timer->start_comm, TASK_COMM_LEN);
- tmp[TASK_COMM_LEN] = 0;
- SEQ_printf(m, ", %s/%d", tmp, timer->start_pid);
-#endif
SEQ_printf(m, "\n");
SEQ_printf(m, " # expires at %Lu-%Lu nsecs [in %Ld to %Ld nsecs]\n",
(unsigned long long)ktime_to_ns(hrtimer_get_softexpires(timer)),
@@ -127,7 +117,7 @@ print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now)
SEQ_printf(m, " .base: %pK\n", base);
SEQ_printf(m, " .index: %d\n", base->index);

- SEQ_printf(m, " .resolution: %u nsecs\n", (unsigned) hrtimer_resolution);
+ SEQ_printf(m, " .resolution: %u nsecs\n", hrtimer_resolution);

SEQ_printf(m, " .get_time: ");
print_name_offset(m, base->get_time);
diff --git a/kernel/time/timer_stats.c b/kernel/time/timer_stats.c
deleted file mode 100644
index afddded947df..000000000000
--- a/kernel/time/timer_stats.c
+++ /dev/null
@@ -1,425 +0,0 @@
-/*
- * kernel/time/timer_stats.c
- *
- * Collect timer usage statistics.
- *
- * Copyright(C) 2006, Red Hat, Inc., Ingo Molnar
- * Copyright(C) 2006 Timesys Corp., Thomas Gleixner <tglx@timesys.com>
- *
- * timer_stats is based on timer_top, a similar functionality which was part of
- * Con Kolivas dyntick patch set. It was developed by Daniel Petrini at the
- * Instituto Nokia de Tecnologia - INdT - Manaus. timer_top's design was based
- * on dynamic allocation of the statistics entries and linear search based
- * lookup combined with a global lock, rather than the static array, hash
- * and per-CPU locking which is used by timer_stats. It was written for the
- * pre hrtimer kernel code and therefore did not take hrtimers into account.
- * Nevertheless it provided the base for the timer_stats implementation and
- * was a helpful source of inspiration. Kudos to Daniel and the Nokia folks
- * for this effort.
- *
- * timer_top.c is
- * Copyright (C) 2005 Instituto Nokia de Tecnologia - INdT - Manaus
- * Written by Daniel Petrini <d.pensator@gmail.com>
- * timer_top.c was released under the GNU General Public License version 2
- *
- * We export the addresses and counting of timer functions being called,
- * the pid and cmdline from the owner process if applicable.
- *
- * Start/stop data collection:
- * # echo [1|0] >/proc/timer_stats
- *
- * Display the information collected so far:
- * # cat /proc/timer_stats
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#include <linux/proc_fs.h>
-#include <linux/module.h>
-#include <linux/spinlock.h>
-#include <linux/sched.h>
-#include <linux/seq_file.h>
-#include <linux/kallsyms.h>
-
-#include <linux/uaccess.h>
-
-/*
- * This is our basic unit of interest: a timer expiry event identified
- * by the timer, its start/expire functions and the PID of the task that
- * started the timer. We count the number of times an event happens:
- */
-struct entry {
- /*
- * Hash list:
- */
- struct entry *next;
-
- /*
- * Hash keys:
- */
- void *timer;
- void *start_func;
- void *expire_func;
- pid_t pid;
-
- /*
- * Number of timeout events:
- */
- unsigned long count;
- u32 flags;
-
- /*
- * We save the command-line string to preserve
- * this information past task exit:
- */
- char comm[TASK_COMM_LEN + 1];
-
-} ____cacheline_aligned_in_smp;
-
-/*
- * Spinlock protecting the tables - not taken during lookup:
- */
-static DEFINE_RAW_SPINLOCK(table_lock);
-
-/*
- * Per-CPU lookup locks for fast hash lookup:
- */
-static DEFINE_PER_CPU(raw_spinlock_t, tstats_lookup_lock);
-
-/*
- * Mutex to serialize state changes with show-stats activities:
- */
-static DEFINE_MUTEX(show_mutex);
-
-/*
- * Collection status, active/inactive:
- */
-int __read_mostly timer_stats_active;
-
-/*
- * Beginning/end timestamps of measurement:
- */
-static ktime_t time_start, time_stop;
-
-/*
- * tstat entry structs only get allocated while collection is
- * active and never freed during that time - this simplifies
- * things quite a bit.
- *
- * They get freed when a new collection period is started.
- */
-#define MAX_ENTRIES_BITS 10
-#define MAX_ENTRIES (1UL << MAX_ENTRIES_BITS)
-
-static unsigned long nr_entries;
-static struct entry entries[MAX_ENTRIES];
-
-static atomic_t overflow_count;
-
-/*
- * The entries are in a hash-table, for fast lookup:
- */
-#define TSTAT_HASH_BITS (MAX_ENTRIES_BITS - 1)
-#define TSTAT_HASH_SIZE (1UL << TSTAT_HASH_BITS)
-#define TSTAT_HASH_MASK (TSTAT_HASH_SIZE - 1)
-
-#define __tstat_hashfn(entry) \
- (((unsigned long)(entry)->timer ^ \
- (unsigned long)(entry)->start_func ^ \
- (unsigned long)(entry)->expire_func ^ \
- (unsigned long)(entry)->pid ) & TSTAT_HASH_MASK)
-
-#define tstat_hashentry(entry) (tstat_hash_table + __tstat_hashfn(entry))
-
-static struct entry *tstat_hash_table[TSTAT_HASH_SIZE] __read_mostly;
-
-static void reset_entries(void)
-{
- nr_entries = 0;
- memset(entries, 0, sizeof(entries));
- memset(tstat_hash_table, 0, sizeof(tstat_hash_table));
- atomic_set(&overflow_count, 0);
-}
-
-static struct entry *alloc_entry(void)
-{
- if (nr_entries >= MAX_ENTRIES)
- return NULL;
-
- return entries + nr_entries++;
-}
-
-static int match_entries(struct entry *entry1, struct entry *entry2)
-{
- return entry1->timer == entry2->timer &&
- entry1->start_func == entry2->start_func &&
- entry1->expire_func == entry2->expire_func &&
- entry1->pid == entry2->pid;
-}
-
-/*
- * Look up whether an entry matching this item is present
- * in the hash already. Must be called with irqs off and the
- * lookup lock held:
- */
-static struct entry *tstat_lookup(struct entry *entry, char *comm)
-{
- struct entry **head, *curr, *prev;
-
- head = tstat_hashentry(entry);
- curr = *head;
-
- /*
- * The fastpath is when the entry is already hashed,
- * we do this with the lookup lock held, but with the
- * table lock not held:
- */
- while (curr) {
- if (match_entries(curr, entry))
- return curr;
-
- curr = curr->next;
- }
- /*
- * Slowpath: allocate, set up and link a new hash entry:
- */
- prev = NULL;
- curr = *head;
-
- raw_spin_lock(&table_lock);
- /*
- * Make sure we have not raced with another CPU:
- */
- while (curr) {
- if (match_entries(curr, entry))
- goto out_unlock;
-
- prev = curr;
- curr = curr->next;
- }
-
- curr = alloc_entry();
- if (curr) {
- *curr = *entry;
- curr->count = 0;
- curr->next = NULL;
- memcpy(curr->comm, comm, TASK_COMM_LEN);
-
- smp_mb(); /* Ensure that curr is initialized before insert */
-
- if (prev)
- prev->next = curr;
- else
- *head = curr;
- }
- out_unlock:
- raw_spin_unlock(&table_lock);
-
- return curr;
-}
-
-/**
- * timer_stats_update_stats - Update the statistics for a timer.
- * @timer: pointer to either a timer_list or a hrtimer
- * @pid: the pid of the task which set up the timer
- * @startf: pointer to the function which did the timer setup
- * @timerf: pointer to the timer callback function of the timer
- * @comm: name of the process which set up the timer
- * @tflags: The flags field of the timer
- *
- * When the timer is already registered, then the event counter is
- * incremented. Otherwise the timer is registered in a free slot.
- */
-void timer_stats_update_stats(void *timer, pid_t pid, void *startf,
- void *timerf, char *comm, u32 tflags)
-{
- /*
- * It doesn't matter which lock we take:
- */
- raw_spinlock_t *lock;
- struct entry *entry, input;
- unsigned long flags;
-
- if (likely(!timer_stats_active))
- return;
-
- lock = &per_cpu(tstats_lookup_lock, raw_smp_processor_id());
-
- input.timer = timer;
- input.start_func = startf;
- input.expire_func = timerf;
- input.pid = pid;
- input.flags = tflags;
-
- raw_spin_lock_irqsave(lock, flags);
- if (!timer_stats_active)
- goto out_unlock;
-
- entry = tstat_lookup(&input, comm);
- if (likely(entry))
- entry->count++;
- else
- atomic_inc(&overflow_count);
-
- out_unlock:
- raw_spin_unlock_irqrestore(lock, flags);
-}
-
-static void print_name_offset(struct seq_file *m, unsigned long addr)
-{
- char symname[KSYM_NAME_LEN];
-
- if (lookup_symbol_name(addr, symname) < 0)
- seq_printf(m, "<%p>", (void *)addr);
- else
- seq_printf(m, "%s", symname);
-}
-
-static int tstats_show(struct seq_file *m, void *v)
-{
- struct timespec64 period;
- struct entry *entry;
- unsigned long ms;
- long events = 0;
- ktime_t time;
- int i;
-
- mutex_lock(&show_mutex);
- /*
- * If still active then calculate up to now:
- */
- if (timer_stats_active)
- time_stop = ktime_get();
-
- time = ktime_sub(time_stop, time_start);
-
- period = ktime_to_timespec64(time);
- ms = period.tv_nsec / 1000000;
-
- seq_puts(m, "Timer Stats Version: v0.3\n");
- seq_printf(m, "Sample period: %ld.%03ld s\n", (long)period.tv_sec, ms);
- if (atomic_read(&overflow_count))
- seq_printf(m, "Overflow: %d entries\n", atomic_read(&overflow_count));
- seq_printf(m, "Collection: %s\n", timer_stats_active ? "active" : "inactive");
-
- for (i = 0; i < nr_entries; i++) {
- entry = entries + i;
- if (entry->flags & TIMER_DEFERRABLE) {
- seq_printf(m, "%4luD, %5d %-16s ",
- entry->count, entry->pid, entry->comm);
- } else {
- seq_printf(m, " %4lu, %5d %-16s ",
- entry->count, entry->pid, entry->comm);
- }
-
- print_name_offset(m, (unsigned long)entry->start_func);
- seq_puts(m, " (");
- print_name_offset(m, (unsigned long)entry->expire_func);
- seq_puts(m, ")\n");
-
- events += entry->count;
- }
-
- ms += period.tv_sec * 1000;
- if (!ms)
- ms = 1;
-
- if (events && period.tv_sec)
- seq_printf(m, "%ld total events, %ld.%03ld events/sec\n",
- events, events * 1000 / ms,
- (events * 1000000 / ms) % 1000);
- else
- seq_printf(m, "%ld total events\n", events);
-
- mutex_unlock(&show_mutex);
-
- return 0;
-}
-
-/*
- * After a state change, make sure all concurrent lookup/update
- * activities have stopped:
- */
-static void sync_access(void)
-{
- unsigned long flags;
- int cpu;
-
- for_each_online_cpu(cpu) {
- raw_spinlock_t *lock = &per_cpu(tstats_lookup_lock, cpu);
-
- raw_spin_lock_irqsave(lock, flags);
- /* nothing */
- raw_spin_unlock_irqrestore(lock, flags);
- }
-}
-
-static ssize_t tstats_write(struct file *file, const char __user *buf,
- size_t count, loff_t *offs)
-{
- char ctl[2];
-
- if (count != 2 || *offs)
- return -EINVAL;
-
- if (copy_from_user(ctl, buf, count))
- return -EFAULT;
-
- mutex_lock(&show_mutex);
- switch (ctl[0]) {
- case '0':
- if (timer_stats_active) {
- timer_stats_active = 0;
- time_stop = ktime_get();
- sync_access();
- }
- break;
- case '1':
- if (!timer_stats_active) {
- reset_entries();
- time_start = ktime_get();
- smp_mb();
- timer_stats_active = 1;
- }
- break;
- default:
- count = -EINVAL;
- }
- mutex_unlock(&show_mutex);
-
- return count;
-}
-
-static int tstats_open(struct inode *inode, struct file *filp)
-{
- return single_open(filp, tstats_show, NULL);
-}
-
-static const struct file_operations tstats_fops = {
- .open = tstats_open,
- .read = seq_read,
- .write = tstats_write,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
-void __init init_timer_stats(void)
-{
- int cpu;
-
- for_each_possible_cpu(cpu)
- raw_spin_lock_init(&per_cpu(tstats_lookup_lock, cpu));
-}
-
-static int __init init_tstats_procfs(void)
-{
- struct proc_dir_entry *pe;
-
- pe = proc_create("timer_stats", 0644, NULL, &tstats_fops);
- if (!pe)
- return -ENOMEM;
- return 0;
-}
-__initcall(init_tstats_procfs);
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 1d9fb6543a66..072cbc9b175d 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1523,8 +1523,6 @@ static void __queue_delayed_work(int cpu, struct workqueue_struct *wq,
return;
}

- timer_stats_timer_set_start_info(&dwork->timer);
-
dwork->wq = wq;
dwork->cpu = cpu;
timer->expires = jiffies + delay;
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index eb9e9a7870fa..132af338d6dd 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -980,20 +980,6 @@ config DEBUG_TIMEKEEPING

If unsure, say N.

-config TIMER_STATS
- bool "Collect kernel timers statistics"
- depends on DEBUG_KERNEL && PROC_FS
- help
- If you say Y here, additional code will be inserted into the
- timer routines to collect statistics about kernel timers being
- reprogrammed. The statistics can be read from /proc/timer_stats.
- The statistics collection is started by writing 1 to /proc/timer_stats,
- writing 0 stops it. This feature is useful to collect information
- about timer usage patterns in kernel and userspace. This feature
- is lightweight if enabled in the kernel config but not activated
- (it defaults to deactivated on bootup and will only be activated
- if some application like powertop activates it explicitly).
-
config DEBUG_PREEMPT
bool "Debug preemptible kernel"
depends on DEBUG_KERNEL && PREEMPT && TRACE_IRQFLAGS_SUPPORT
diff --git a/lib/timerqueue.c b/lib/timerqueue.c
index adc6ee0a5126..4a720ed4fdaf 100644
--- a/lib/timerqueue.c
+++ b/lib/timerqueue.c
@@ -80,8 +80,7 @@ bool timerqueue_del(struct timerqueue_head *head, struct timerqueue_node *node)
if (head->next == node) {
struct rb_node *rbn = rb_next(&node->node);

- head->next = rbn ?
- rb_entry(rbn, struct timerqueue_node, node) : NULL;
+ head->next = rb_entry_safe(rbn, struct timerqueue_node, node);
}
rb_erase(&node->node, &head->head);
RB_CLEAR_NODE(&node->node);
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