For the error codes used only in __ASSERT() statements fix compilation
warnings like:
...
warning: variable 'err' set but not used [-Wunused-but-set-variable]
int err;
^
...
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
In order to bring consistency in-tree, migrate all lib 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>
Make it possible to "finish" with fewer bytes than what was "claimed".
This was possible before on the get side, but the put side was
cummulative wrt finish. The revamp made it cummulative on both sides.
Turns out that existing users rely on the opposite behavior which is
more logical and useful. So make both sides that way.
Adjust documentation, test case and users accordingly.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
The item mode is really a specialization of the byte mode. And in-tree
usage shows the byte mode is prominent. It feels more natural if the
byte mode is presented first with the item mode second. Swap the code
and documentation order accordingly. No code change.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
This code is rather hairy. When I look at it I don't like the way it
stares back at me.
First, the rewind business looks fishy. It has to die.
And we don't have to rely on modulus either. Not even for non-power-of-2
buffers. Let's kill that distinction too and make all sizes always
"high performance".
The code is now entirely relying only on simple ALU operations (add,
sub and compare).
The key assumption: 32-bit values do wrap around after max range has
been reached. No saturation. All architectures supported by Zephyr
do that.
Some stats:
lib/os/ring_buffer.c: 62 insertions(+), 124 deletions(-)
ring_buffer.c.obj before after diff
----------------------------------------------
frdm_k64f 1224 1136 -88
m2gl025_miv 2485 2079 -406
mps2_an385 1228 1132 -96
mps2_an521 1228 1132 -96
native_posix 1546 1496 -50
native_posix_64 1598 1595 -3
nsim_hs_mpuv6 1252 1192 -60
nsim_hs_smp 1252 1192 -60
nsim_sem 1252 1192 -60
qemu_arc_em 1324 1192 -132
qemu_arc_hs6x 1824 1620 -204
qemu_arc_hs 1252 1192 -60
qemu_cortex_a53_smp 2154 1888 -266
qemu_cortex_a53 2154 1888 -266
qemu_cortex_a9 1938 1792 -146
Before (qemu_cortex_a53):
START - test_ringbuffer_performance
1 byte put-get, avg cycles: 52
4 byte put-get, avg cycles: 47
1 byte put claim-finish, avg cycles: 39
5 byte put claim-finish, avg cycles: 41
5 byte get claim-finish, avg cycles: 52
PASS - test_ringbuffer_performance in 0.8 seconds
After (qemu_cortex_a53):
START - test_ringbuffer_performance
1 byte put-get, avg cycles: 34
4 byte put-get, avg cycles: 41
1 byte put claim-finish, avg cycles: 27
5 byte put claim-finish, avg cycles: 29
5 byte get claim-finish, avg cycles: 29
PASS - test_ringbuffer_performance in 0.4 seconds
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Conceptually, ring_buf_item_put() and ring_buf_item_get() are specialized
versions of ring_buf_put() and ring_buf_get(). Make it so to rationalize
the code to open the way for more optimizations.
This means we need specialized wrappers on top of ring_buf_init()
accordingly, given that the core machinery is now common and byte based.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Two issues were found:
- subtracting rewinding value from head could result in negative value
- calling ring_buf_put_claim after tail got rewinded but before head
got rewinded resulted in error.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
Removed unused functions, or moved inside #ifdefs.
This allows using -Werror=unused-function on the clang compiler. Tested
by building the ChromeOS EC on all supported platforms with
-Werror=unused-functions.
Signed-off-by: Jeremy Bettis <jbettis@google.com>
Ring buffer claims that no synchronization is needed
when there is a single producer and single consumer.
However, recent changes have broken that promise since
indexes rewind mechanism was modifing head and tail
when consuming. Patch fixes that by spliting rewinding
of indexes so that producer rewinds tail only and
consumer rewinds head.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
Add ring_buf_size_get() to get the number of bytes currently available
in the ring buffer.
Add ring_buf_peek() to read data from the head of a ring buffer without
removal.
Fixes#37145
Signed-off-by: Christopher Friedt <chrisfriedt@gmail.com>
Allow NULL data buffers to be provided to `ring_buf_get` and
`ring_buf_item_get`, in which case data will be discarded instead of
copied out to the user.
Fixes#33488.
Signed-off-by: Jordan Yates <jordan.yates@data61.csiro.au>
This symbol is reserved and usage of reserved symbols violates the
coding guidelines. (MISRA 21.2)
NAME
fgetpos, fseek, fsetpos, ftell, rewind - reposition a stream
SYNOPSIS
#include <stdio.h>
void rewind(FILE *stream);
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Previously, ring buffer had capacity of provided buffer size - 1. This
trick was used to distinguish between empty and full states. It had one
drawback: ring buffer could not be used as a pool of equal sized buffers
(using ring_buf_put_claim and ring_buf_get_claim).
Reworked internals to use non wrapping head and tail. Since they are
non wrapping, there is no issue with distinguishing between empty and
full. Since this appraoch would be vulnerable to wrapping on 32 bit
boundary, added a mechanism which periodically reduces all indexes to
avoid 32 bit wrapping.
After this rework, buffer has one byte more capacity. Simple test shows
slight performance improvement.
Updated tests to reflect increased capacity and added test to check if
it is possible to continuesly allocated 2 buffers of half ring buffer
size.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
move ring_buffer.h to sys/ring_buffer.h and
create a shim for backward-compatibility.
No functional changes to the headers.
A warning in the shim can be controlled with CONFIG_COMPAT_INCLUDES.
Related to #16539
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Some function return values were not handled. Added assert in case
those functions return error. It is possible only if same ring buffer
instance is used without any protection from multiple contexts.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
There are issues using lowercase min and max macros when compiling a C++
application with a third-party toolchain such as GNU ARM Embedded when
using some STL headers i.e. <chrono>.
This is because there are actual C++ functions called min and max
defined in some of the STL headers and these macros interfere with them.
By changing the macros to UPPERCASE, which is consistent with almost all
other pre-processor macros this naming conflict is avoided.
All files that use these macros have been updated.
Signed-off-by: Carlos Stuart <carlosstuart1970@gmail.com>
lib/ was starting to get messy and inconsitent. Files being either
dumped in the root or in sub-directories without a clear plan.
Move all library components into one single folder and call it 'os'.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2019-01-22 07:45:22 -05:00
Renamed from lib/ring_buffer/ring_buffer.c (Browse further)
