Commit graph

266 commits

Author SHA1 Message Date
Joel Holdsworth
58499aca7c arch: nios2: Rename _Fault to z_nios2_fault
The exception fault handler function is named _Fault which is inconsistent
with all other arch-specific functions present in Zephyr. This patch
replaces the name with z_nios2_fault.

Signed-off-by: Joel Holdsworth <jholdsworth@nvidia.com>
2025-01-28 23:42:06 +01:00
Joel Holdsworth
bdb3f4fd73 arch: nios2: Corrected a typo
An existing comment references a function "irq_oflload()", which should be
written "irq_offload()".

This issue was detecte by the GitHub CI compliance check.

Signed-off-by: Joel Holdsworth <jholdsworth@nvidia.com>
2025-01-28 23:42:06 +01:00
Dmitrii Golovanov
d2c19a0535 arch: nios2: timing: Fix timing cycles rollover
Fix arch_timing_cycles_get() to prevent overflow on the clock rollover.

The issue is observable on tests/benchmarks/wait_queues and
tests/benchmarks/sched_queues with BENCHMARK_NUM_ITERATIONS is large
enough, e.g. default 1000.

Signed-off-by: Dmitrii Golovanov <dmitrii.golovanov@intel.com>
2025-01-06 17:13:10 +00:00
Peter Mitsis
909ff45f0c kernel: arch: move arch_swap() declaration
Moves the arch_swap() declaration out of kernel_arch_interface.h
and into the various architectures' kernel_arch_func.h. This
permits the arch_swap() to be inlined on ARM, but extern'd on
the other architectures that still implement arch_swap().

Inlining this function on ARM has shown at least a +5% performance
boost according to the thread_metric benchmark on the disco_l475_iot1
board.

Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
2024-12-11 21:33:49 +01:00
Yong Cong Sin
de347a4e07 init: support per-core init hook
Allow SoC to implement their custom per-core initialization function by
selecting `CONFIG_SOC_PER_CORE_INIT_HOOK` and implement
`soc_per_core_init_hook()`.

Signed-off-by: Maxim Adelman <imax@meta.com>
Signed-off-by: Yong Cong Sin <ycsin@meta.com>
Signed-off-by: Yong Cong Sin <yongcong.sin@gmail.com>
2024-11-16 14:04:25 -05:00
Anas Nashif
7e225efab7 arch: initialize irq_offload during boot, do not use SYS_INIT
Do not use SYS_INIT for initializing irq_offload when enabled, instead
using a new interface that is called during the boot process for all
architectures.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-09-17 20:05:22 -04:00
Anas Nashif
6ec74d02b6 cache: add new interface arch_cache_init() for initializing cache
Add a new call for initializing cache on architectures that need that.
Avoid using SYS_INIT for this and instead call the hook in a fixed place
and run if implemented.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-09-17 20:05:22 -04:00
Anas Nashif
e260d03686 init: introduce soc and board hooks
Introduce soc and board hooks to replace arch specific code
and replace usages of SYS_INIT for platform initialization.

include/zephyr/platform/hooks.h introduces the hooks to be implemented
by boards and SoCs.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-09-09 10:07:33 +02:00
Anas Nashif
a91c6e56c8 arch: use same syntax for custom arch calls
Use same Kconfig syntax for those  custom arch call.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-08-12 12:43:36 +02:00
Anas Nashif
7f52fc4188 arch: custom cpu_idle and cpu_atomic harmonization
custom arch_cpu_idle and arch_cpu_atomic_idle implementation was done
differently on different architectures. riscv implemented those as weak
symbols, xtensa used a kconfig and all other architectures did not
really care, but this was a global kconfig that should apply to all
architectures.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-08-12 12:43:36 +02:00
Yong Cong Sin
6a3cb93d88 arch: remove the use of z_arch_esf_t completely from internal
Created `GEN_OFFSET_STRUCT` & `GEN_NAMED_OFFSET_STRUCT` that
works for `struct`, and remove the use of `z_arch_esf_t`
completely.

Signed-off-by: Yong Cong Sin <ycsin@meta.com>
2024-06-04 14:02:51 -05:00
Yong Cong Sin
e54b27b967 arch: define struct arch_esf and deprecate z_arch_esf_t
Make `struct arch_esf` compulsory for all architectures by
declaring it in the `arch_interface.h` header.

After this commit, the named struct `z_arch_esf_t` is only used
internally to generate offsets, and is slated to be removed
from the `arch_interface.h` header in the future.

Signed-off-by: Yong Cong Sin <ycsin@meta.com>
2024-06-04 14:02:51 -05:00
Yong Cong Sin
bbe5e1e6eb build: namespace the generated headers with zephyr/
Namespaced the generated headers with `zephyr` to prevent
potential conflict with other headers.

Introduce a temporary Kconfig `LEGACY_GENERATED_INCLUDE_PATH`
that is enabled by default. This allows the developers to
continue the use of the old include paths for the time being
until it is deprecated and eventually removed. The Kconfig will
generate a build-time warning message, similar to the
`CONFIG_TIMER_RANDOM_GENERATOR`.

Updated the includes path of in-tree sources accordingly.

Most of the changes here are scripted, check the PR for more
info.

Signed-off-by: Yong Cong Sin <ycsin@meta.com>
2024-05-28 22:03:55 +02:00
Anas Nashif
e25f31ab78 arch: guard more code with CONFIG_EXCEPTION_DEBUG
It should be possible to disable exception debug, which is enabled by
default to reduce image size. Add missing guards now that the option is
cross architecture.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2023-12-14 09:32:27 +01:00
Anas Nashif
9f3ed1b2b3 arch: _PrepC -> z_prep_c
Rename to use common naming for z_prep_c applied to all architectures.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2023-12-11 18:23:52 -05:00
Peter Mitsis
d84582081f arch: nios2: Remove unused absolute symbols
Removes NIOS2 specific unused absolute symbols that are defined
via the GEN_ABSOLUTE_SYM() macro.

Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
2023-04-18 10:51:28 -04:00
Simon Hein
b5522fffbc arch: comply to coding guidelines MISRA C:2012 Rule 14.4
MISRA C:2012 Rule 14.4 (The controlling expression of an if statement
and the controlling expression of an iteration-statement shall have
essentially Boolean type.)

Use `do { ... } while (false)' instead of `do { ... } while (0)'.
Use comparisons with zero instead of implicitly testing integers.
Use comparisons with NULL instead of implicitly testing pointers.
Use comparisons with NUL instead of implicitly testing plain chars.

This commit is a subset of the original auditable-branch commit:
5d02614e34a86b549c7707d3d9f0984bc3a5f22a

Signed-off-by: Simon Hein <SHein@baumer.com>
2022-07-20 09:28:38 -05:00
Gerard Marull-Paretas
4b91c2d79f asm: update files with <zephyr/...> include prefix
Assembler files were not migrated with the new <zephyr/...> prefix.
Note that the conversion has been scripted, refer to #45388 for more
details.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
2022-05-09 12:45:29 -04:00
Gerard Marull-Paretas
16811660ee arch: migrate includes to <zephyr/...>
In order to bring consistency in-tree, migrate all arch code to the new
prefix <zephyr/...>. Note that the conversion has been scripted, refer
to zephyrproject-rtos#45388 for more details.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
2022-05-06 19:57:22 +02:00
Carlo Caione
240c975ad4 core: z_data_copy does not depend on CONFIG_XIP
When XIP is not enabled, z_data_copy() already falls back to an empty
function. No need to ifdef it.

Signed-off-by: Carlo Caione <ccaione@baylibre.com>
2022-02-22 10:22:53 +01:00
Daniel Leung
ceca27cd44 nios2: remove @return doc for void functions
For functions returning nothing, there is no need to document
with @return, as Doxgen complains about "documented empty
return type of ...".

Signed-off-by: Daniel Leung <daniel.leung@intel.com>
2022-01-12 16:02:16 -05:00
Flavio Ceolin
9285b4c6bf arch: nios2: Fix 10.4 violations
Both operands of an operator in which the usual arithmetic
conversions are performed shall have the same essential
type category.

Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
2021-04-10 09:59:37 -04:00
Krzysztof Chruscinski
3ed8083dc1 kernel: Cleanup logger setup in kernel files
Most of kernel files where declaring os module without providing
log level. Because of that default log level was used instead of
CONFIG_KERNEL_LOG_LEVEL.

Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
2020-11-27 09:56:34 -05:00
Daniel Leung
270ce0b850 nios2: fix register saving during thread switch instrumentation
This changes to use stack to store registers before calling thread
switch instrumentation functions, instead of using the thread's
register saving struct.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>
2020-11-11 23:55:49 -05:00
Daniel Leung
11e6b43090 tracing: roll thread switch in/out into thread stats functions
Since the tracing of thread being switched in/out has the same
instrumentation points, we can roll the tracing function calls
into the one for thread stats gathering functions.
This avoids duplicating code to call another function.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>
2020-11-11 23:55:49 -05:00
Daniel Leung
9be37553ee timing: do not repeatedly do init()/start()/stop()
We should not be initializing/starting/stoping timing functions
multiple times. So this changes how the timing functions are
structured to allow only one initialization, only start when
stopped, and only stop when started.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>
2020-11-11 23:55:49 -05:00
Anas Nashif
6e27478c3d benchmarking: remove execution benchmarking code
This code had one purpose only, feed timing information into a test and
was not used by anything else. The custom trace points unfortunatly were
not accurate and this test was delivering informatin that conflicted
with other tests we have due to placement of such trace points in the
architecture and kernel code.

For such measurements we are planning to use the tracing functionality
in a special mode that would be used for metrics without polluting the
architecture and kernel code with additional tracing and timing code.

Furthermore, much of the assembly code used had issues.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
2020-09-05 13:28:38 -05:00
Anas Nashif
150c82c8f9 arch: nios2: add timing implementation
Add timing implementation for NIOS2 architecture.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2020-09-05 13:28:38 -05:00
Tomasz Bursztyka
93cd336204 arch: Apply dynamic IRQ API change
Switching to constant parameter.

Fixes #27399

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
2020-09-02 13:48:13 +02:00
Tomasz Bursztyka
7def6eeaee arch: Apply IRQ offload API change
Switching to constant parameter.

Fixes #27399

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
2020-09-02 13:48:13 +02:00
Chris Coleman
99a268fa16 arch: arm: Collect full register state in Cortex-M Exception Stack Frame
To debug hard-to-reproduce faults/panics, it's helpful to get the full
register state at the time a fault occurred. This enables recovering
full backtraces and the state of local variables at the time of a
crash.

This PR introduces a new Kconfig option, CONFIG_EXTRA_EXCEPTION_INFO,
to facilitate this use case. The option enables the capturing of the
callee-saved register state (r4-r11 & exc_return) during a fault. The
info is forwarded to `k_sys_fatal_error_handler` in the z_arch_esf_t
parameter. From there, the data can be saved for post-mortem analysis.

To test the functionality a new unit test was added to
tests/arch/arm_interrupt which verifies the register contents passed
in the argument match the state leading up to a crash.

Signed-off-by: Chris Coleman <chris@memfault.com>
2020-08-31 10:13:27 +02:00
Anas Nashif
c1a2c7992b tracing: nios2: fix swap tracing
Fixed ordering of tracepoints for the nios2 architecture.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2020-08-24 13:21:12 +02:00
Anas Nashif
ce59510127 arch: xip: cleanup XIP Kconfig
unify how XIP is configured across architectures. Use imply instead of
setting defaults per architecture and imply XIP on riscv arch and remove
XIP configuration from individual defconfig files to match other
architectures.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2020-08-07 09:50:22 -04:00
Carles Cufi
244f826e3c cmake: remove _if_kconfig() functions
This set of functions seem to be there just because of historical
reasons, stemming from Kbuild. They are non-obvious and prone to errors,
so remove them in favor of the `_ifdef()` ones with an explicit
`CONFIG_` condition.

Script used:

git grep -l _if_kconfig | xargs sed -E -i
"s/_if_kconfig\(\s*(\w*)/_ifdef(CONFIG_\U\1\E \1/g"

Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
2020-08-01 12:35:20 +02:00
Andrew Boie
b0c155f3ca kernel: overhaul stack specification
The core kernel computes the initial stack pointer
for a thread, properly aligning it and subtracting out
any random offsets or thread-local storage areas.
arch_new_thread() no longer needs to make any calculations,
an initial stack frame may be placed at the bounds of
the new 'stack_ptr' parameter passed in. This parameter
replaces 'stack_size'.

thread->stack_info is now set before arch_new_thread()
is invoked, z_new_thread_init() has been removed.
The values populated may need to be adjusted on arches
which carve-out MPU guard space from the actual stack
buffer.

thread->stack_info now has a new member 'delta' which
indicates any offset applied for TLS or random offset.
It's used so the calculations don't need to be repeated
if the thread later drops to user mode.

CONFIG_INIT_STACKS logic is now performed inside
z_setup_new_thread(), before arch_new_thread() is called.

thread->stack_info is now defined as the canonical
user-accessible area within the stack object, including
random offsets and TLS. It will never include any
carved-out memory for MPU guards and must be updated at
runtime if guards are removed.

Available stack space is now optimized. Some arches may
need to significantly round up the buffer size to account
for page-level granularity or MPU power-of-two requirements.
This space is now accounted for and used by virtue of
the Z_THREAD_STACK_SIZE_ADJUST() call in z_setup_new_thread.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-07-30 21:11:14 -04:00
Andrew Boie
24825c8667 arches: fix arch_new_thread param names
MISRA-C wants the parameter names in a function implementaion
to match the names used by the header prototype.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-07-30 21:11:14 -04:00
Andrew Boie
62eb7d99dc arch_interface: remove unnecessary params
arch_new_thread() passes along the thread priority and option
flags, but these are already initialized in thread->base and
can be accessed there if needed.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-07-30 21:11:14 -04:00
Kumar Gala
a1b77fd589 zephyr: replace zephyr integer types with C99 types
git grep -l 'u\(8\|16\|32\|64\)_t' | \
		xargs sed -i "s/u\(8\|16\|32\|64\)_t/uint\1_t/g"
	git grep -l 's\(8\|16\|32\|64\)_t' | \
		xargs sed -i "s/s\(8\|16\|32\|64\)_t/int\1_t/g"

Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
2020-06-08 08:23:57 -05:00
Andrew Boie
a203d21962 kernel: remove legacy fields in _kernel
UP should just use _kernel.cpus[0].

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-05-08 17:42:49 +02:00
Andrew Boie
618426d6e7 kernel: add Z_STACK_PTR_ALIGN ARCH_STACK_PTR_ALIGN
This operation is formally defined as rounding down a potential
stack pointer value to meet CPU and ABI requirments.

This was previously defined ad-hoc as STACK_ROUND_DOWN().

A new architecture constant ARCH_STACK_PTR_ALIGN is added.
Z_STACK_PTR_ALIGN() is defined in terms of it. This used to
be inconsistently specified as STACK_ALIGN or STACK_PTR_ALIGN;
in the latter case, STACK_ALIGN meant something else, typically
a required alignment for the base of a stack buffer.

STACK_ROUND_UP() only used in practice by Risc-V, delete
elsewhere.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-04-21 18:45:45 -04:00
Andrew Boie
1f6f977f05 kernel: centralize new thread priority check
This was being done inconsistently in arch_new_thread(), just
move to the core kernel.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-04-21 18:45:45 -04:00
Andrew Boie
c0df99cc77 kernel: reduce scope of z_new_thread_init()
The core kernel z_setup_new_thread() calls into arch_new_thread(),
which calls back into the core kernel via z_new_thread_init().

Move everything that doesn't have to be in z_new_thread_init() to
z_setup_new_thread() and convert to an inline function.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-04-21 18:45:45 -04:00
Andrew Boie
80a0d9d16b kernel: interrupt/idle stacks/threads as array
The set of interrupt stacks is now expressed as an array. We
also define the idle threads and their associated stacks this
way. This allows for iteration in cases where we have multiple
CPUs.

There is now a centralized declaration in kernel_internal.h.

On uniprocessor systems, z_interrupt_stacks has one element
and can be used in the same way as _interrupt_stack.

The IRQ stack for CPU 0 is now set in init.c instead of in
arch code.

The extern definition of the main thread stack is now removed,
this doesn't need to be in a header.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-03-16 23:17:36 +02:00
Andrew Boie
0a41f06159 nios2: add arch_irq_is_enabled()
This arch API was never implemented on this architecture.

Fixes: #9994

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-03-10 12:06:54 -04:00
Anas Nashif
73008b427c tracing: move headers under include/tracing
Move tracing.h to include/tracing/ to align with subsystem reorg.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2020-02-07 15:58:05 -05:00
Wentong Wu
aa5d45d7cc tracing: add TRACING_ISR Kconfig
Add TRACING_ISR Kconfig to help high latency backend working well.

Currently the ISR tracing hook function is put at the begining and
ending of ISR wrapper, when there is ISR needed in the tracing path
(especially tracing backend), it will cause tracing buffer easily
be exhausted if async tracing method enabled. Also it will increase
system latency if all the ISRs are traced. So add TRACING_ISR to
enable/disable ISR tracing here. Later a filter out mechanism based
on irq number will be added.

Signed-off-by: Wentong Wu <wentong.wu@intel.com>
2020-02-05 23:54:26 -05:00
Ulf Magnusson
984bfae831 global: Remove leading/trailing blank lines in files
Remove leading/trailing blank lines in .c, .h, .py, .rst, .yml, and
.yaml files.

Will avoid failures with the new CI test in
https://github.com/zephyrproject-rtos/ci-tools/pull/112, though it only
checks changed files.

Move the 'target-notes' target in boards/xtensa/odroid_go/doc/index.rst
to get rid of the trailing blank line there. It was probably misplaced.

Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
2019-12-11 19:17:27 +01:00
Andrew Boie
4f77c2ad53 kernel: rename z_arch_ to arch_
Promote the private z_arch_* namespace, which specifies
the interface between the core kernel and the
architecture code, to a new top-level namespace named
arch_*.

This allows our documentation generation to create
online documentation for this set of interfaces,
and this set of interfaces is worth treating in a
more formal way anyway.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-11-07 15:21:46 -08:00
Stephanos Ioannidis
7bcfdadf81 arch: Simplify private header include path configuration.
When compiling the components under the arch directory, the compiler
include paths for arch and kernel private headers need to be specified.

This was previously done by adding 'zephyr_library_include_directories'
to CMakeLists.txt file for every component under the arch directory,
and this resulted in a significant amount of duplicate code.

This commit uses the CMake 'include_directories' command in the root
CMakeLists.txt to simplify specification of the private header include
paths for all the arch components.

Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
2019-11-06 16:07:32 -08:00
Stephanos Ioannidis
2d7460482d headers: Refactor kernel and arch headers.
This commit refactors kernel and arch headers to establish a boundary
between private and public interface headers.

The refactoring strategy used in this commit is detailed in the issue

This commit introduces the following major changes:

1. Establish a clear boundary between private and public headers by
  removing "kernel/include" and "arch/*/include" from the global
  include paths. Ideally, only kernel/ and arch/*/ source files should
  reference the headers in these directories. If these headers must be
  used by a component, these include paths shall be manually added to
  the CMakeLists.txt file of the component. This is intended to
  discourage applications from including private kernel and arch
  headers either knowingly and unknowingly.

  - kernel/include/ (PRIVATE)
    This directory contains the private headers that provide private
   kernel definitions which should not be visible outside the kernel
   and arch source code. All public kernel definitions must be added
   to an appropriate header located under include/.

  - arch/*/include/ (PRIVATE)
    This directory contains the private headers that provide private
   architecture-specific definitions which should not be visible
   outside the arch and kernel source code. All public architecture-
   specific definitions must be added to an appropriate header located
   under include/arch/*/.

  - include/ AND include/sys/ (PUBLIC)
    This directory contains the public headers that provide public
   kernel definitions which can be referenced by both kernel and
   application code.

  - include/arch/*/ (PUBLIC)
    This directory contains the public headers that provide public
   architecture-specific definitions which can be referenced by both
   kernel and application code.

2. Split arch_interface.h into "kernel-to-arch interface" and "public
  arch interface" divisions.

  - kernel/include/kernel_arch_interface.h
    * provides private "kernel-to-arch interface" definition.
    * includes arch/*/include/kernel_arch_func.h to ensure that the
     interface function implementations are always available.
    * includes sys/arch_interface.h so that public arch interface
     definitions are automatically included when including this file.

  - arch/*/include/kernel_arch_func.h
    * provides architecture-specific "kernel-to-arch interface"
     implementation.
    * only the functions that will be used in kernel and arch source
     files are defined here.

  - include/sys/arch_interface.h
    * provides "public arch interface" definition.
    * includes include/arch/arch_inlines.h to ensure that the
     architecture-specific public inline interface function
     implementations are always available.

  - include/arch/arch_inlines.h
    * includes architecture-specific arch_inlines.h in
     include/arch/*/arch_inline.h.

  - include/arch/*/arch_inline.h
    * provides architecture-specific "public arch interface" inline
     function implementation.
    * supersedes include/sys/arch_inline.h.

3. Refactor kernel and the existing architecture implementations.

  - Remove circular dependency of kernel and arch headers. The
   following general rules should be observed:

    * Never include any private headers from public headers
    * Never include kernel_internal.h in kernel_arch_data.h
    * Always include kernel_arch_data.h from kernel_arch_func.h
    * Never include kernel.h from kernel_struct.h either directly or
     indirectly. Only add the kernel structures that must be referenced
     from public arch headers in this file.

  - Relocate syscall_handler.h to include/ so it can be used in the
   public code. This is necessary because many user-mode public codes
   reference the functions defined in this header.

  - Relocate kernel_arch_thread.h to include/arch/*/thread.h. This is
   necessary to provide architecture-specific thread definition for
   'struct k_thread' in kernel.h.

  - Remove any private header dependencies from public headers using
   the following methods:

    * If dependency is not required, simply omit
    * If dependency is required,
      - Relocate a portion of the required dependencies from the
       private header to an appropriate public header OR
      - Relocate the required private header to make it public.

This commit supersedes #20047, addresses #19666, and fixes #3056.

Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
2019-11-06 16:07:32 -08:00