a6dc4412ba
misc/rwlock:Implementing read/write locks.
...
A new locking mechanism: read/write locks
When there is a writer it is not possible to put on a read lock or a write lock; when there is a reader it is possible to reenter the read lock but not the write lock.
Writers are exclusive locks, readers are shared locks.
At the same time through the waiter count to determine whether there is currently a blocked task, if there is then in the unlock time to wake up all the waiter, through the priority of the competition to complete the blocked lock execution.
For example:
When we have a reader blocking two waiter writers, when the reader is unlocked it wakes up both writers. The writer with higher priority wakes up and checks for a successful condition and locks the lock, the second writer wakes up and fails to check for a condition and continues to block the lock.
Signed-off-by: chenrun1 <chenrun1@xiaomi.com>
2023-12-02 19:43:19 -08:00
8935ac4cc3
sched: Author Gregory Nutt: update licenses to Apache
...
Gregory Nutt has submitted the SGA and we can mograte the licenses
to Apache.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
2021-02-09 01:21:53 -08:00
33ec242caf
Implement proposed POSIX _clockwait variants of existing _timedwait functions
...
Here is the related glibc patchset:
https://patchwork.ozlabs.org/project/glibc/cover/cover.b0c66849a87ca79889a49f2f1f2563b1a8a15d8b.1551291557.git-series.mac@mcrowe.com/
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: I0095cb34cef3d0d88a100255053da79266b73ff2
2020-07-27 20:39:59 -03:00
73fc186beb
sem_setprotocol: Handle a case of missing proxy for sem_setprotocol. Reorder so that (1) this error is avoided, and (2) >No proxy is needed if priority inheritance is not enabled.
2016-11-03 18:51:38 -06:00
4c8ec0d2ca
include/nuttx/semaphore.h: Fix broken macros
2016-11-03 12:49:44 -06:00
b738a646ad
sem_getprotocol() can be in C library
2016-11-02 09:29:16 -06:00
92d3022411
Add pthread_mutexattr_get/set_protocol and non-standard sem_get/set_protocol. These may use to enable or disable priority inheritance on a single semaphore.
2016-11-02 09:05:18 -06:00
5d63cd85c7
sched/semaphore: Add an internal interface to reset a semaphore count.
2016-03-05 07:33:24 -06:00
2c0ad2564f
Add CONFIG_SPINLOCK. Also need spinunlock() and spinlock_initialize()
2016-02-09 15:31:14 -06:00
2c66e0eb2a
sem_tickwait(): Add a new, non-standard function to perform timed semaphore waits. It is functionally equialent to the standard sem_timedwait(), but more efficient for use in higher performance device drivers. Requested by Max Neklyudov
2015-08-01 07:31:09 -06:00
826f5516ff
Semaphores: sem_waitirq.c must be built when signals are disabled. That is because not handles not only the case of semaphore wait being awakened by a signal, but also the case with sem_timedwait.c when the semaphore wait is awakened by a timeout.
2014-12-28 15:03:12 -06:00
b3a1939020
Sempahores: Add logic to clean up after task_delete() or pthread_cancel() if the task happens to be waiting on a semaphore when it is cancelled
2014-12-13 12:02:25 -06:00
322f9f401c
Simplify how C source files are selected in the build
2014-10-07 07:42:36 -06:00
8c958be5ab
Semaphore initialization is now only required if priority inheritance is initialized
2014-09-29 06:50:48 -06:00
650a0d0615
Completes VFS-based named semaphore implemetation. Still a little buggy
2014-09-28 15:58:56 -06:00
e10a23ae50
Move environment files from sched/ to sched/environ
2014-08-08 13:53:29 -06:00
chenrun1