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-rw-r--r--Documentation/RCU/Design/Requirements/Requirements.html22
-rw-r--r--Documentation/RCU/torture.txt15
-rw-r--r--Documentation/acpi/acpi-lid.txt96
-rw-r--r--Documentation/acpi/gpio-properties.txt10
-rw-r--r--Documentation/arm64/silicon-errata.txt2
-rw-r--r--Documentation/devicetree/bindings/arm/arch_timer.txt6
-rw-r--r--Documentation/devicetree/bindings/devfreq/event/rockchip-dfi.txt19
-rw-r--r--Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt209
-rw-r--r--Documentation/kernel-parameters.txt9
-rw-r--r--Documentation/static-keys.txt9
10 files changed, 377 insertions, 20 deletions
diff --git a/Documentation/RCU/Design/Requirements/Requirements.html b/Documentation/RCU/Design/Requirements/Requirements.html
index ece410f..a4d3838 100644
--- a/Documentation/RCU/Design/Requirements/Requirements.html
+++ b/Documentation/RCU/Design/Requirements/Requirements.html
@@ -2493,6 +2493,28 @@ or some future “lazy”
variant of <tt>call_rcu()</tt> that might one day be created for
energy-efficiency purposes.
+<p>
+That said, there are limits.
+RCU requires that the <tt>rcu_head</tt> structure be aligned to a
+two-byte boundary, and passing a misaligned <tt>rcu_head</tt>
+structure to one of the <tt>call_rcu()</tt> family of functions
+will result in a splat.
+It is therefore necessary to exercise caution when packing
+structures containing fields of type <tt>rcu_head</tt>.
+Why not a four-byte or even eight-byte alignment requirement?
+Because the m68k architecture provides only two-byte alignment,
+and thus acts as alignment's least common denominator.
+
+<p>
+The reason for reserving the bottom bit of pointers to
+<tt>rcu_head</tt> structures is to leave the door open to
+&ldquo;lazy&rdquo; callbacks whose invocations can safely be deferred.
+Deferring invocation could potentially have energy-efficiency
+benefits, but only if the rate of non-lazy callbacks decreases
+significantly for some important workload.
+In the meantime, reserving the bottom bit keeps this option open
+in case it one day becomes useful.
+
<h3><a name="Performance, Scalability, Response Time, and Reliability">
Performance, Scalability, Response Time, and Reliability</a></h3>
diff --git a/Documentation/RCU/torture.txt b/Documentation/RCU/torture.txt
index 118e7c1..278f6a9 100644
--- a/Documentation/RCU/torture.txt
+++ b/Documentation/RCU/torture.txt
@@ -10,21 +10,6 @@ status messages via printk(), which can be examined via the dmesg
command (perhaps grepping for "torture"). The test is started
when the module is loaded, and stops when the module is unloaded.
-CONFIG_RCU_TORTURE_TEST_RUNNABLE
-
-It is also possible to specify CONFIG_RCU_TORTURE_TEST=y, which will
-result in the tests being loaded into the base kernel. In this case,
-the CONFIG_RCU_TORTURE_TEST_RUNNABLE config option is used to specify
-whether the RCU torture tests are to be started immediately during
-boot or whether the /proc/sys/kernel/rcutorture_runnable file is used
-to enable them. This /proc file can be used to repeatedly pause and
-restart the tests, regardless of the initial state specified by the
-CONFIG_RCU_TORTURE_TEST_RUNNABLE config option.
-
-You will normally -not- want to start the RCU torture tests during boot
-(and thus the default is CONFIG_RCU_TORTURE_TEST_RUNNABLE=n), but doing
-this can sometimes be useful in finding boot-time bugs.
-
MODULE PARAMETERS
diff --git a/Documentation/acpi/acpi-lid.txt b/Documentation/acpi/acpi-lid.txt
new file mode 100644
index 0000000..effe7af
--- /dev/null
+++ b/Documentation/acpi/acpi-lid.txt
@@ -0,0 +1,96 @@
+Special Usage Model of the ACPI Control Method Lid Device
+
+Copyright (C) 2016, Intel Corporation
+Author: Lv Zheng <lv.zheng@intel.com>
+
+
+Abstract:
+
+Platforms containing lids convey lid state (open/close) to OSPMs using a
+control method lid device. To implement this, the AML tables issue
+Notify(lid_device, 0x80) to notify the OSPMs whenever the lid state has
+changed. The _LID control method for the lid device must be implemented to
+report the "current" state of the lid as either "opened" or "closed".
+
+For most platforms, both the _LID method and the lid notifications are
+reliable. However, there are exceptions. In order to work with these
+exceptional buggy platforms, special restrictions and expections should be
+taken into account. This document describes the restrictions and the
+expections of the Linux ACPI lid device driver.
+
+
+1. Restrictions of the returning value of the _LID control method
+
+The _LID control method is described to return the "current" lid state.
+However the word of "current" has ambiguity, some buggy AML tables return
+the lid state upon the last lid notification instead of returning the lid
+state upon the last _LID evaluation. There won't be difference when the
+_LID control method is evaluated during the runtime, the problem is its
+initial returning value. When the AML tables implement this control method
+with cached value, the initial returning value is likely not reliable.
+There are platforms always retun "closed" as initial lid state.
+
+2. Restrictions of the lid state change notifications
+
+There are buggy AML tables never notifying when the lid device state is
+changed to "opened". Thus the "opened" notification is not guaranteed. But
+it is guaranteed that the AML tables always notify "closed" when the lid
+state is changed to "closed". The "closed" notification is normally used to
+trigger some system power saving operations on Windows. Since it is fully
+tested, it is reliable from all AML tables.
+
+3. Expections for the userspace users of the ACPI lid device driver
+
+The ACPI button driver exports the lid state to the userspace via the
+following file:
+ /proc/acpi/button/lid/LID0/state
+This file actually calls the _LID control method described above. And given
+the previous explanation, it is not reliable enough on some platforms. So
+it is advised for the userspace program to not to solely rely on this file
+to determine the actual lid state.
+
+The ACPI button driver emits the following input event to the userspace:
+ SW_LID
+The ACPI lid device driver is implemented to try to deliver the platform
+triggered events to the userspace. However, given the fact that the buggy
+firmware cannot make sure "opened"/"closed" events are paired, the ACPI
+button driver uses the following 3 modes in order not to trigger issues.
+
+If the userspace hasn't been prepared to ignore the unreliable "opened"
+events and the unreliable initial state notification, Linux users can use
+the following kernel parameters to handle the possible issues:
+A. button.lid_init_state=method:
+ When this option is specified, the ACPI button driver reports the
+ initial lid state using the returning value of the _LID control method
+ and whether the "opened"/"closed" events are paired fully relies on the
+ firmware implementation.
+ This option can be used to fix some platforms where the returning value
+ of the _LID control method is reliable but the initial lid state
+ notification is missing.
+ This option is the default behavior during the period the userspace
+ isn't ready to handle the buggy AML tables.
+B. button.lid_init_state=open:
+ When this option is specified, the ACPI button driver always reports the
+ initial lid state as "opened" and whether the "opened"/"closed" events
+ are paired fully relies on the firmware implementation.
+ This may fix some platforms where the returning value of the _LID
+ control method is not reliable and the initial lid state notification is
+ missing.
+
+If the userspace has been prepared to ignore the unreliable "opened" events
+and the unreliable initial state notification, Linux users should always
+use the following kernel parameter:
+C. button.lid_init_state=ignore:
+ When this option is specified, the ACPI button driver never reports the
+ initial lid state and there is a compensation mechanism implemented to
+ ensure that the reliable "closed" notifications can always be delievered
+ to the userspace by always pairing "closed" input events with complement
+ "opened" input events. But there is still no guarantee that the "opened"
+ notifications can be delivered to the userspace when the lid is actually
+ opens given that some AML tables do not send "opened" notifications
+ reliably.
+ In this mode, if everything is correctly implemented by the platform
+ firmware, the old userspace programs should still work. Otherwise, the
+ new userspace programs are required to work with the ACPI button driver.
+ This option will be the default behavior after the userspace is ready to
+ handle the buggy AML tables.
diff --git a/Documentation/acpi/gpio-properties.txt b/Documentation/acpi/gpio-properties.txt
index f35dad1..5aafe0b3 100644
--- a/Documentation/acpi/gpio-properties.txt
+++ b/Documentation/acpi/gpio-properties.txt
@@ -28,8 +28,8 @@ index, like the ASL example below shows:
ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
Package ()
{
- Package () {"reset-gpio", Package() {^BTH, 1, 1, 0 }},
- Package () {"shutdown-gpio", Package() {^BTH, 0, 0, 0 }},
+ Package () {"reset-gpios", Package() {^BTH, 1, 1, 0 }},
+ Package () {"shutdown-gpios", Package() {^BTH, 0, 0, 0 }},
}
})
}
@@ -48,7 +48,7 @@ Since ACPI GpioIo() resource does not have a field saying whether it is
active low or high, the "active_low" argument can be used here. Setting
it to 1 marks the GPIO as active low.
-In our Bluetooth example the "reset-gpio" refers to the second GpioIo()
+In our Bluetooth example the "reset-gpios" refers to the second GpioIo()
resource, second pin in that resource with the GPIO number of 31.
ACPI GPIO Mappings Provided by Drivers
@@ -83,8 +83,8 @@ static const struct acpi_gpio_params reset_gpio = { 1, 1, false };
static const struct acpi_gpio_params shutdown_gpio = { 0, 0, false };
static const struct acpi_gpio_mapping bluetooth_acpi_gpios[] = {
- { "reset-gpio", &reset_gpio, 1 },
- { "shutdown-gpio", &shutdown_gpio, 1 },
+ { "reset-gpios", &reset_gpio, 1 },
+ { "shutdown-gpios", &shutdown_gpio, 1 },
{ },
};
diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt
index ccc6032..405da11 100644
--- a/Documentation/arm64/silicon-errata.txt
+++ b/Documentation/arm64/silicon-errata.txt
@@ -61,3 +61,5 @@ stable kernels.
| Cavium | ThunderX GICv3 | #23154 | CAVIUM_ERRATUM_23154 |
| Cavium | ThunderX Core | #27456 | CAVIUM_ERRATUM_27456 |
| Cavium | ThunderX SMMUv2 | #27704 | N/A |
+| | | | |
+| Freescale/NXP | LS2080A/LS1043A | A-008585 | FSL_ERRATUM_A008585 |
diff --git a/Documentation/devicetree/bindings/arm/arch_timer.txt b/Documentation/devicetree/bindings/arm/arch_timer.txt
index e774128..ef5fbe9 100644
--- a/Documentation/devicetree/bindings/arm/arch_timer.txt
+++ b/Documentation/devicetree/bindings/arm/arch_timer.txt
@@ -25,6 +25,12 @@ to deliver its interrupts via SPIs.
- always-on : a boolean property. If present, the timer is powered through an
always-on power domain, therefore it never loses context.
+- fsl,erratum-a008585 : A boolean property. Indicates the presence of
+ QorIQ erratum A-008585, which says that reading the counter is
+ unreliable unless the same value is returned by back-to-back reads.
+ This also affects writes to the tval register, due to the implicit
+ counter read.
+
** Optional properties:
- arm,cpu-registers-not-fw-configured : Firmware does not initialize
diff --git a/Documentation/devicetree/bindings/devfreq/event/rockchip-dfi.txt b/Documentation/devicetree/bindings/devfreq/event/rockchip-dfi.txt
new file mode 100644
index 0000000..f223313
--- /dev/null
+++ b/Documentation/devicetree/bindings/devfreq/event/rockchip-dfi.txt
@@ -0,0 +1,19 @@
+
+* Rockchip rk3399 DFI device
+
+Required properties:
+- compatible: Must be "rockchip,rk3399-dfi".
+- reg: physical base address of each DFI and length of memory mapped region
+- rockchip,pmu: phandle to the syscon managing the "pmu general register files"
+- clocks: phandles for clock specified in "clock-names" property
+- clock-names : the name of clock used by the DFI, must be "pclk_ddr_mon";
+
+Example:
+ dfi: dfi@0xff630000 {
+ compatible = "rockchip,rk3399-dfi";
+ reg = <0x00 0xff630000 0x00 0x4000>;
+ rockchip,pmu = <&pmugrf>;
+ clocks = <&cru PCLK_DDR_MON>;
+ clock-names = "pclk_ddr_mon";
+ status = "disabled";
+ };
diff --git a/Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt b/Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt
new file mode 100644
index 0000000..7a9e860
--- /dev/null
+++ b/Documentation/devicetree/bindings/devfreq/rk3399_dmc.txt
@@ -0,0 +1,209 @@
+* Rockchip rk3399 DMC(Dynamic Memory Controller) device
+
+Required properties:
+- compatible: Must be "rockchip,rk3399-dmc".
+- devfreq-events: Node to get DDR loading, Refer to
+ Documentation/devicetree/bindings/devfreq/
+ rockchip-dfi.txt
+- interrupts: The interrupt number to the CPU. The interrupt
+ specifier format depends on the interrupt controller.
+ It should be DCF interrupts, when DDR dvfs finish,
+ it will happen.
+- clocks: Phandles for clock specified in "clock-names" property
+- clock-names : The name of clock used by the DFI, must be
+ "pclk_ddr_mon";
+- operating-points-v2: Refer to Documentation/devicetree/bindings/power/opp.txt
+ for details.
+- center-supply: DMC supply node.
+- status: Marks the node enabled/disabled.
+
+Following properties are ddr timing:
+
+- rockchip,dram_speed_bin : Value reference include/dt-bindings/clock/ddr.h,
+ it select ddr3 cl-trp-trcd type, default value
+ "DDR3_DEFAULT".it must selected according to
+ "Speed Bin" in ddr3 datasheet, DO NOT use
+ smaller "Speed Bin" than ddr3 exactly is.
+
+- rockchip,pd_idle : Config the PD_IDLE value, defined the power-down
+ idle period, memories are places into power-down
+ mode if bus is idle for PD_IDLE DFI clocks.
+
+- rockchip,sr_idle : Configure the SR_IDLE value, defined the
+ selfrefresh idle period, memories are places
+ into self-refresh mode if bus is idle for
+ SR_IDLE*1024 DFI clocks (DFI clocks freq is
+ half of dram's clocks), defaule value is "0".
+
+- rockchip,sr_mc_gate_idle : Defined the self-refresh with memory and
+ controller clock gating idle period, memories
+ are places into self-refresh mode and memory
+ controller clock arg gating if bus is idle for
+ sr_mc_gate_idle*1024 DFI clocks.
+
+- rockchip,srpd_lite_idle : Defined the self-refresh power down idle
+ period, memories are places into self-refresh
+ power down mode if bus is idle for
+ srpd_lite_idle*1024 DFI clocks. This parameter
+ is for LPDDR4 only.
+
+- rockchip,standby_idle : Defined the standby idle period, memories are
+ places into self-refresh than controller, pi,
+ phy and dram clock will gating if bus is idle
+ for standby_idle * DFI clocks.
+
+- rockchip,dram_dll_disb_freq : It's defined the DDR3 dll bypass frequency in
+ MHz, when ddr freq less than DRAM_DLL_DISB_FREQ,
+ ddr3 dll will bypssed note: if dll was bypassed,
+ the odt also stop working.
+
+- rockchip,phy_dll_disb_freq : Defined the PHY dll bypass frequency in
+ MHz (Mega Hz), when ddr freq less than
+ DRAM_DLL_DISB_FREQ, phy dll will bypssed.
+ note: phy dll and phy odt are independent.
+
+- rockchip,ddr3_odt_disb_freq : When dram type is DDR3, this parameter defined
+ the odt disable frequency in MHz (Mega Hz),
+ when ddr frequency less then ddr3_odt_disb_freq,
+ the odt on dram side and controller side are
+ both disabled.
+
+- rockchip,ddr3_drv : When dram type is DDR3, this parameter define
+ the dram side driver stength in ohm, default
+ value is DDR3_DS_40ohm.
+
+- rockchip,ddr3_odt : When dram type is DDR3, this parameter define
+ the dram side ODT stength in ohm, default value
+ is DDR3_ODT_120ohm.
+
+- rockchip,phy_ddr3_ca_drv : When dram type is DDR3, this parameter define
+ the phy side CA line(incluing command line,
+ address line and clock line) driver strength.
+ Default value is PHY_DRV_ODT_40.
+
+- rockchip,phy_ddr3_dq_drv : When dram type is DDR3, this parameter define
+ the phy side DQ line(incluing DQS/DQ/DM line)
+ driver strength. default value is PHY_DRV_ODT_40.
+
+- rockchip,phy_ddr3_odt : When dram type is DDR3, this parameter define the
+ phy side odt strength, default value is
+ PHY_DRV_ODT_240.
+
+- rockchip,lpddr3_odt_disb_freq : When dram type is LPDDR3, this parameter defined
+ then odt disable frequency in MHz (Mega Hz),
+ when ddr frequency less then ddr3_odt_disb_freq,
+ the odt on dram side and controller side are
+ both disabled.
+
+- rockchip,lpddr3_drv : When dram type is LPDDR3, this parameter define
+ the dram side driver stength in ohm, default
+ value is LP3_DS_34ohm.
+
+- rockchip,lpddr3_odt : When dram type is LPDDR3, this parameter define
+ the dram side ODT stength in ohm, default value
+ is LP3_ODT_240ohm.
+
+- rockchip,phy_lpddr3_ca_drv : When dram type is LPDDR3, this parameter define
+ the phy side CA line(incluing command line,
+ address line and clock line) driver strength.
+ default value is PHY_DRV_ODT_40.
+
+- rockchip,phy_lpddr3_dq_drv : When dram type is LPDDR3, this parameter define
+ the phy side DQ line(incluing DQS/DQ/DM line)
+ driver strength. default value is
+ PHY_DRV_ODT_40.
+
+- rockchip,phy_lpddr3_odt : When dram type is LPDDR3, this parameter define
+ the phy side odt strength, default value is
+ PHY_DRV_ODT_240.
+
+- rockchip,lpddr4_odt_disb_freq : When dram type is LPDDR4, this parameter
+ defined the odt disable frequency in
+ MHz (Mega Hz), when ddr frequency less then
+ ddr3_odt_disb_freq, the odt on dram side and
+ controller side are both disabled.
+
+- rockchip,lpddr4_drv : When dram type is LPDDR4, this parameter define
+ the dram side driver stength in ohm, default
+ value is LP4_PDDS_60ohm.
+
+- rockchip,lpddr4_dq_odt : When dram type is LPDDR4, this parameter define
+ the dram side ODT on dqs/dq line stength in ohm,
+ default value is LP4_DQ_ODT_40ohm.
+
+- rockchip,lpddr4_ca_odt : When dram type is LPDDR4, this parameter define
+ the dram side ODT on ca line stength in ohm,
+ default value is LP4_CA_ODT_40ohm.
+
+- rockchip,phy_lpddr4_ca_drv : When dram type is LPDDR4, this parameter define
+ the phy side CA line(incluing command address
+ line) driver strength. default value is
+ PHY_DRV_ODT_40.
+
+- rockchip,phy_lpddr4_ck_cs_drv : When dram type is LPDDR4, this parameter define
+ the phy side clock line and cs line driver
+ strength. default value is PHY_DRV_ODT_80.
+
+- rockchip,phy_lpddr4_dq_drv : When dram type is LPDDR4, this parameter define
+ the phy side DQ line(incluing DQS/DQ/DM line)
+ driver strength. default value is PHY_DRV_ODT_80.
+
+- rockchip,phy_lpddr4_odt : When dram type is LPDDR4, this parameter define
+ the phy side odt strength, default value is
+ PHY_DRV_ODT_60.
+
+Example:
+ dmc_opp_table: dmc_opp_table {
+ compatible = "operating-points-v2";
+
+ opp00 {
+ opp-hz = /bits/ 64 <300000000>;
+ opp-microvolt = <900000>;
+ };
+ opp01 {
+ opp-hz = /bits/ 64 <666000000>;
+ opp-microvolt = <900000>;
+ };
+ };
+
+ dmc: dmc {
+ compatible = "rockchip,rk3399-dmc";
+ devfreq-events = <&dfi>;
+ interrupts = <GIC_SPI 1 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&cru SCLK_DDRCLK>;
+ clock-names = "dmc_clk";
+ operating-points-v2 = <&dmc_opp_table>;
+ center-supply = <&ppvar_centerlogic>;
+ upthreshold = <15>;
+ downdifferential = <10>;
+ rockchip,ddr3_speed_bin = <21>;
+ rockchip,pd_idle = <0x40>;
+ rockchip,sr_idle = <0x2>;
+ rockchip,sr_mc_gate_idle = <0x3>;
+ rockchip,srpd_lite_idle = <0x4>;
+ rockchip,standby_idle = <0x2000>;
+ rockchip,dram_dll_dis_freq = <300>;
+ rockchip,phy_dll_dis_freq = <125>;
+ rockchip,auto_pd_dis_freq = <666>;
+ rockchip,ddr3_odt_dis_freq = <333>;
+ rockchip,ddr3_drv = <DDR3_DS_40ohm>;
+ rockchip,ddr3_odt = <DDR3_ODT_120ohm>;
+ rockchip,phy_ddr3_ca_drv = <PHY_DRV_ODT_40>;
+ rockchip,phy_ddr3_dq_drv = <PHY_DRV_ODT_40>;
+ rockchip,phy_ddr3_odt = <PHY_DRV_ODT_240>;
+ rockchip,lpddr3_odt_dis_freq = <333>;
+ rockchip,lpddr3_drv = <LP3_DS_34ohm>;
+ rockchip,lpddr3_odt = <LP3_ODT_240ohm>;
+ rockchip,phy_lpddr3_ca_drv = <PHY_DRV_ODT_40>;
+ rockchip,phy_lpddr3_dq_drv = <PHY_DRV_ODT_40>;
+ rockchip,phy_lpddr3_odt = <PHY_DRV_ODT_240>;
+ rockchip,lpddr4_odt_dis_freq = <333>;
+ rockchip,lpddr4_drv = <LP4_PDDS_60ohm>;
+ rockchip,lpddr4_dq_odt = <LP4_DQ_ODT_40ohm>;
+ rockchip,lpddr4_ca_odt = <LP4_CA_ODT_40ohm>;
+ rockchip,phy_lpddr4_ca_drv = <PHY_DRV_ODT_40>;
+ rockchip,phy_lpddr4_ck_cs_drv = <PHY_DRV_ODT_80>;
+ rockchip,phy_lpddr4_dq_drv = <PHY_DRV_ODT_80>;
+ rockchip,phy_lpddr4_odt = <PHY_DRV_ODT_60>;
+ status = "disabled";
+ };
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index a4f4d69..25037de 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -698,6 +698,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
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/static-keys.txt b/Documentation/static-keys.txt
index 477927b..ea8d7b4 100644
--- a/Documentation/static-keys.txt
+++ b/Documentation/static-keys.txt
@@ -15,6 +15,8 @@ The updated API replacements are:
DEFINE_STATIC_KEY_TRUE(key);
DEFINE_STATIC_KEY_FALSE(key);
+DEFINE_STATIC_KEY_ARRAY_TRUE(keys, count);
+DEFINE_STATIC_KEY_ARRAY_FALSE(keys, count);
static_branch_likely()
static_branch_unlikely()
@@ -140,6 +142,13 @@ static_branch_inc(), will change the branch back to true. Likewise, if the
key is initialized false, a 'static_branch_inc()', will change the branch to
true. And then a 'static_branch_dec()', will again make the branch false.
+Where an array of keys is required, it can be defined as:
+
+ DEFINE_STATIC_KEY_ARRAY_TRUE(keys, count);
+
+or:
+
+ DEFINE_STATIC_KEY_ARRAY_FALSE(keys, count);
4) Architecture level code patching interface, 'jump labels'