Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 166 insertions, 0 deletions

diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig
new file mode 100644
index 000000000..c999c4a1e
--- /dev/null
+++ b/drivers/devfreq/Kconfig
@@ -0,0 +1,166 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menuconfig PM_DEVFREQ
+	bool "Generic Dynamic Voltage and Frequency Scaling (DVFS) support"
+	select PM_OPP
+	help
+	  A device may have a list of frequencies and voltages available.
+	  devfreq, a generic DVFS framework can be registered for a device
+	  in order to let the governor provided to devfreq choose an
+	  operating frequency based on the device driver's policy.
+
+	  Each device may have its own governor and policy. Devfreq can
+	  reevaluate the device state periodically and/or based on the
+	  notification to "nb", a notifier block, of devfreq.
+
+	  Like some CPUs with CPUfreq, a device may have multiple clocks.
+	  However, because the clock frequencies of a single device are
+	  determined by the single device's state, an instance of devfreq
+	  is attached to a single device and returns a "representative"
+	  clock frequency of the device, which is also attached
+	  to a device by 1-to-1. The device registering devfreq takes the
+	  responsibility to "interpret" the representative frequency and
+	  to set its every clock accordingly with the "target" callback
+	  given to devfreq.
+
+	  When OPP is used with the devfreq device, it is recommended to
+	  register devfreq's nb to the OPP's notifier head.  If OPP is
+	  used with the devfreq device, you may use OPP helper
+	  functions defined in devfreq.h.
+
+if PM_DEVFREQ
+
+comment "DEVFREQ Governors"
+
+config DEVFREQ_GOV_SIMPLE_ONDEMAND
+	tristate "Simple Ondemand"
+	help
+	  Chooses frequency based on the recent load on the device. Works
+	  similar as ONDEMAND governor of CPUFREQ does. A device with
+	  Simple-Ondemand should be able to provide busy/total counter
+	  values that imply the usage rate. A device may provide tuned
+	  values to the governor with data field at devfreq_add_device().
+
+config DEVFREQ_GOV_PERFORMANCE
+	tristate "Performance"
+	help
+	  Sets the frequency at the maximum available frequency.
+	  This governor always returns UINT_MAX as frequency so that
+	  the DEVFREQ framework returns the highest frequency available
+	  at any time.
+
+config DEVFREQ_GOV_POWERSAVE
+	tristate "Powersave"
+	help
+	  Sets the frequency at the minimum available frequency.
+	  This governor always returns 0 as frequency so that
+	  the DEVFREQ framework returns the lowest frequency available
+	  at any time.
+
+config DEVFREQ_GOV_USERSPACE
+	tristate "Userspace"
+	help
+	  Sets the frequency at the user specified one.
+	  This governor returns the user configured frequency if there
+	  has been an input to /sys/devices/.../userspace/set_freq.
+	  Otherwise, the governor does not change the frequency
+	  given at the initialization.
+
+config DEVFREQ_GOV_PASSIVE
+	tristate "Passive"
+	help
+	  Sets the frequency based on the frequency of its parent devfreq
+	  device. This governor does not change the frequency by itself
+	  through sysfs entries. The passive governor recommends that
+	  devfreq device uses the OPP table to get the frequency/voltage.
+
+comment "DEVFREQ Drivers"
+
+config ARM_EXYNOS_BUS_DEVFREQ
+	tristate "ARM Exynos Generic Memory Bus DEVFREQ Driver"
+	depends on ARCH_EXYNOS || COMPILE_TEST
+	select DEVFREQ_GOV_SIMPLE_ONDEMAND
+	select DEVFREQ_GOV_PASSIVE
+	select DEVFREQ_EVENT_EXYNOS_PPMU
+	select PM_DEVFREQ_EVENT
+	help
+	  This adds the common DEVFREQ driver for Exynos Memory bus. Exynos
+	  Memory bus has one more group of memory bus (e.g, MIF and INT block).
+	  Each memory bus group could contain many memoby bus block. It reads
+	  PPMU counters of memory controllers by using DEVFREQ-event device
+	  and adjusts the operating frequencies and voltages with OPP support.
+	  This does not yet operate with optimal voltages.
+
+config ARM_HISI_UNCORE_DEVFREQ
+	tristate "HiSilicon uncore DEVFREQ Driver"
+	depends on ACPI && ACPI_PPTT && PCC
+	select DEVFREQ_GOV_PERFORMANCE
+	select DEVFREQ_GOV_USERSPACE
+	help
+	  This adds a DEVFREQ driver that manages uncore frequency scaling for
+	  HiSilicon Kunpeng SoCs. This enables runtime management of uncore
+	  frequency scaling from kernel and userspace. The uncore domain
+	  contains system interconnects and L3 cache.
+
+config ARM_IMX_BUS_DEVFREQ
+	tristate "i.MX Generic Bus DEVFREQ Driver"
+	depends on ARCH_MXC || COMPILE_TEST
+	select DEVFREQ_GOV_USERSPACE
+	help
+	  This adds the generic DEVFREQ driver for i.MX interconnects. It
+	  allows adjusting NIC/NOC frequency.
+
+config ARM_IMX8M_DDRC_DEVFREQ
+	tristate "i.MX8M DDRC DEVFREQ Driver"
+	depends on (ARCH_MXC && HAVE_ARM_SMCCC) || \
+		(COMPILE_TEST && HAVE_ARM_SMCCC)
+	select DEVFREQ_GOV_USERSPACE
+	help
+	  This adds the DEVFREQ driver for the i.MX8M DDR Controller. It allows
+	  adjusting DRAM frequency.
+
+config ARM_TEGRA_DEVFREQ
+	tristate "NVIDIA Tegra30/114/124/210 DEVFREQ Driver"
+	depends on ARCH_TEGRA_3x_SOC || ARCH_TEGRA_114_SOC || \
+		ARCH_TEGRA_132_SOC || ARCH_TEGRA_124_SOC || \
+		ARCH_TEGRA_210_SOC || \
+		COMPILE_TEST
+	depends on COMMON_CLK
+	help
+	  This adds the DEVFREQ driver for the Tegra family of SoCs.
+	  It reads ACTMON counters of memory controllers and adjusts the
+	  operating frequencies and voltages with OPP support.
+
+config ARM_MEDIATEK_CCI_DEVFREQ
+	tristate "MEDIATEK CCI DEVFREQ Driver"
+	depends on ARM_MEDIATEK_CPUFREQ || COMPILE_TEST
+	select DEVFREQ_GOV_PASSIVE
+	help
+	  This adds a devfreq driver for MediaTek Cache Coherent Interconnect
+	  which is shared the same regulators with the cpu cluster. It can track
+	  buck voltages and update a proper CCI frequency. Use the notification
+	  to get the regulator status.
+
+config ARM_RK3399_DMC_DEVFREQ
+	tristate "ARM RK3399 DMC DEVFREQ Driver"
+	depends on (ARCH_ROCKCHIP && HAVE_ARM_SMCCC) || \
+		(COMPILE_TEST && HAVE_ARM_SMCCC)
+	select DEVFREQ_EVENT_ROCKCHIP_DFI
+	select DEVFREQ_GOV_SIMPLE_ONDEMAND
+	select PM_DEVFREQ_EVENT
+	help
+	  This adds the DEVFREQ driver for the RK3399 DMC(Dynamic Memory Controller).
+	  It sets the frequency for the memory controller and reads the usage counts
+	  from hardware.
+
+config ARM_SUN8I_A33_MBUS_DEVFREQ
+	tristate "sun8i/sun50i MBUS DEVFREQ Driver"
+	depends on ARCH_SUNXI || COMPILE_TEST
+	depends on COMMON_CLK
+	select DEVFREQ_GOV_SIMPLE_ONDEMAND
+	help
+	  This adds the DEVFREQ driver for the MBUS controller in some
+	  Allwinner sun8i (A33 through H3) and sun50i (A64 and H5) SoCs.
+
+source "drivers/devfreq/event/Kconfig"
+
+endif # PM_DEVFREQ