Gregory Nutt
e24f281401
This commit adds a new internal interfaces and fixes a problem with three APIs in the SMP configuration. The new internal interface is sched_cpu_pause(tcb). This function will pause a CPU if the task associated with 'tcb' is running on that CPU. This allows a different CPU to modify that OS data stuctures associated with the CPU. When the other CPU is resumed, those modifications can safely take place.
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The three fixes are to handle cases in the SMP configuration where one CPU does need to make modifications to TCB and data structures on a task that could be running running on another CPU. Those three cases are task_delete(), task_restart(), and execution of signal handles. In all three cases the solutions is basically the same: (1) Call sched_cpu_pause(tcb) to pause the CPU on which the task is running, (2) perform the necessary operations, then (3) call up_cpu_resume() to restart the paused CPU.
2016-11-20 07:57:18 -06:00
Gregory Nutt
f40fbaa4b9
sched/task: task_restart() test not supported on SMP systems. This is not fully implemented.
2016-11-19 11:41:05 -06:00
Rajan Gill
0d8e191d69
sched/clock: Correct calculation for the case of Tickless mode with a 32-bit timer. In that case, the calculation was returning millisecond accuracy. That is not good when the timer accuracy is < 1 msec.
2016-11-19 09:55:21 -06:00
Gregory Nutt
5ca9128c38
Update comments
2016-11-19 08:33:55 -06:00
Gregory Nutt
ceacacbc63
vfork(): Fix a race condition in the SMP case. Existing logic depended on the fact that the child would not run until waitpid was called because the child had the same priority as the parent. BUT in the SMP case that is not true... the child may run immediately on a different CPU.
2016-11-19 07:30:01 -06:00
Gregory Nutt
69e9f8638d
Most interrupt handling logic interacts with tasks via standard mechanism such as sem_post, sigqueue, mq_send, etc. This all call enter_critical_section and are assumed to be safe in the SMP case.
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But certain logic interacts with tasks in different ways. The only one that comes to mind are wdogs. There is a tasking interface that to manipulate wdogs, and a different interface in the timer interrupt handling logic to manage wdog expirations.
In the normal case, this is fine. Since the tasking level code calls enter_critical_section, interrupts are disabled an no conflicts can occur. But that may not be the case in the SMP case. Most architectures do not permit disabling interrupts on other CPUs so enter_critical_section must work differently: Locks are required to protect code.
So this change adds locking (via enter_critical section) to wdog expiration logic for the the case if the SMP configuration.
2016-11-18 13:57:30 -06:00
Gregory Nutt
78fd358023
Update some comments.
2016-11-18 08:20:52 -06:00
Gregory Nutt
8602e8a8a9
SMP: irq_csection() has a bad assumption. It assumed that the state of certain variables. That was true on entry into the interrupt handler, but might change to the execution of logic within the interrupt handler.
2016-11-18 07:38:16 -06:00
Gregory Nutt
8e029f019b
Update comments
2016-11-17 17:30:12 -06:00
Gregory Nutt
47b52a2633
Fix an error in manually bringing in Sebastien's changes; Update some comments.
2016-11-17 16:15:06 -06:00
Gregory Nutt
9acd57c819
Fix up some naming and update some comments.
2016-11-17 15:50:39 -06:00
Gregory Nutt
558f4049d4
sched/irq/irq_csection: Fix a bad DEBUG assertion when SMP is enabled.
2016-11-17 15:36:27 -06:00
Gregory Nutt
2c314464a8
Fix a typo in a comment
2016-11-17 08:03:45 -06:00
Gregory Nutt
ccdc11d8ff
Fix typo in variable naming. g_cpu_irqset should be g_cpu_irqlock.
2016-11-17 06:37:24 -06:00
Gregory Nutt
1c1564f0c1
Add logic to handled nested calls to enter_critical_section() from interrupts handlers (with SMP).
2016-11-16 22:45:08 -06:00
Gregory Nutt
0c3207e86e
Fix backward logic in an assertion.
2016-11-16 21:48:27 -06:00
Gregory Nutt
16f0b8fa96
Fix typos in DEBUASSERT statements
2016-11-16 19:58:51 -06:00
Gregory Nutt
f1e4951a8d
Fix some comments
2016-11-16 19:11:31 -06:00
Gregory Nutt
4ca653a1cc
Add some experimental changes to enter/leave_critical_section to deal with the case where interrupts are disabled only on the local CPU
2016-11-16 18:28:35 -06:00
Gregory Nutt
5ce3b399d5
Correct some typos in comments
2016-11-15 16:48:40 -06:00
Gregory Nutt
40d7216a22
Back out 65ab12 and parts of 21f92b
2016-11-15 15:44:43 -06:00
Gregory Nutt
6683f01444
Trivial change to comment
2016-11-15 13:38:43 -06:00
Gregory Nutt
21f92ba601
Review some SMP logic; update comments; refresh configuration.
2016-11-15 09:24:00 -06:00
Gregory Nutt
65ab12fbb9
If SMP is enabled, if any interrupt handler calls enter_critical_section(), it should take the spinlock.
2016-11-15 08:37:58 -06:00
Gregory Nutt
b53866c872
sched/irq: Change order for SMP case in enter_critical_section: Disble local interrupts BEFORE taking spinlock.
2016-11-15 07:54:18 -06:00
Freddie Chopin
484a1b6104
sem_wait() and sem_trywait() no longer modify the errno value UNLESS an error occurs. This allows these functions to be used internallly without clobbering the errno value.
2016-11-09 07:01:49 -06:00
Gregory Nutt
120d29b480
Update some Kconfig comments
2016-11-06 09:06:37 -06:00
Heesub Shin
8e94d8e7cc
Signal sent from work_signal() may interrupt the low priority worker thread that is already running. For example, the worker thread that is waiting for a semaphore could be woken up by the signal and break any synchronization assumption as a result. It also does not make any sense to send signal if it is already running and busy. This commit fixes it.
2016-11-06 08:00:12 -06:00
Gregory Nutt
796969f6b6
Update TODO. Provide do-nothing stubs for mutex attribute interfaces if features not enabled. pthread_cond includes a signaling semaphore and should call sem_setprotocol.
2016-11-05 11:06:52 -06:00
Gregory Nutt
6f1c5e7b43
Add some comments.
2016-11-05 09:44:29 -06:00
Gregory Nutt
4b0372e542
Missing # on endif
2016-11-03 21:27:52 -06:00
Gregory Nutt
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
Gregory Nutt
0d5bd30943
Fix a type in include file name
2016-11-03 12:58:02 -06:00
Gregory Nutt
4c8ec0d2ca
include/nuttx/semaphore.h: Fix broken macros
2016-11-03 12:49:44 -06:00
Gregory Nutt
1da3a5fa61
sched: Disable priority inheritance on all semaphores used for signaling
2016-11-03 12:42:02 -06:00
Gregory Nutt
97bf82ee05
Semaphores: Provide macros for sem_setprotobol() and sem_getprotocol() if priority inheritance is not enabled. More SEM_PRIO_* definitions to include/nuttx/semaphore.h
2016-11-02 18:21:46 -06:00
Gregory Nutt
d5b4d848d3
Move protoypes for the non-standard include/semaphore.h file to the non-standard include/nuttx/semaphore.h with the other non-standard semaphore interfaces.
2016-11-02 14:43:03 -06:00
Gregory Nutt
b738a646ad
sem_getprotocol() can be in C library
2016-11-02 09:29:16 -06:00
Gregory Nutt
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
Gregory Nutt
4997ec7a1e
ESP32 Core V2: Add an SMP configuration to support development (not yet usable).
2016-10-29 14:56:07 -06:00
Gregory Nutt
e6377641a8
sched/Kconfig: Add ranges to START_YEAR, MONTH, and DAY
2016-10-27 18:04:14 -06:00
Gregory Nutt
123c520db4
Correct time initialization for the case where time is initialized from settings in the .config file. The correct range for month (tm_mon) internally is 0-11, not 1-12 as it is in the .config file.
2016-10-27 08:36:24 -06:00
Gregory Nutt
6a20560ba2
Trivia fix to typo in comment
2016-10-26 12:29:36 -06:00
Gregory Nutt
3e13ed2400
Within the OS, when a thread obtains a semaphore count it must call sem_addholder() if CONFIG_PRIORITY_INHERITANCE is enabled. If a count is available, then sem_wait() calls sem_addholder(), otherwise it waited for the semaphore and called sem_addholder() when it eventually received the count.
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This caused a problem when the thread calling sem_wait() was very low priority. When it received the count, there may be higher priority threads "hogging" the CPU that prevent the lower priority task from running and, as a result, the sem_addholder() may be delayed indefinitely.
The fix was to have sem_post() call sem_addholder() just before restarting the thread waiting for the semaphore count.
This problem was noted by Benix Vincent who also suggested the solution.
2016-10-26 07:23:15 -06:00
Gregory Nutt
8669183852
sched/pthread and task: When a pthread is started, there is a small bit of logic that will run on the thread of execution of the new pthread. In the case where the new pthread has a lower priority than the parent thread, then this could cause both the parent thread and the new pthread to be blocked at the priority of the lower priority pthread (assuming that CONFIG_PRIORITY_INHERITANCE is not selected).
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This change temporarily boosts the priority of the new pthread to at least the priority of the new pthread to at least the priority of the parent thread. When that bit of logic has executed on the thread of execution of the new pthread, it will then drop to the correct priority (if necessary) before calling into the new pthread's entry point.
2016-10-01 11:38:22 -06:00
Gregory Nutt
75104b0808
Remove duplicate function prototype from wrong header file
2016-10-01 10:56:42 -06:00
Sagitta Li
9fa1024eef
vector table should have dimension NR_IRQS, not NR_IRQS+1
2016-09-22 07:56:12 -06:00
Gregory Nutt
f0b4705d57
Correct a comment
2016-09-15 13:10:42 -06:00
Gregory Nutt
e3bbfa2d85
mq_send() was not setting the errno value on certain failures to allocate a message
2016-09-15 12:42:24 -06:00
Gregory Nutt
368f241637
Correct some comments
2016-09-15 08:46:41 -06:00
