This PR is a modification that optimizes priority inheritance
for only one holder. After the above modifications are completed,
the mutex lock->unlock process that supports priority inheritance
can be optimized by 200 cycles.
Before modify: 2000 cycle
After modify: 1742 cycle
Signed-off-by: zhangyuan21 <zhangyuan21@xiaomi.com>
Store the old environment in a local context so another temporary address
environment can be selected. This can happen especially when a process
is being loaded (the new process's mappings are temporarily instantiated)
and and interrupt occurs.
- The code will detect an error condition described in
https://cwiki.apache.org/confluence/display/NUTTX/Signaling+Semaphores+and+Priority+Inheritance
- The kernel will go to PANIC if semaphore holder can't be allocated even
if CONFIG_DEBUG_ASSERTIONS is disabled
- Clean-up code that handled posing of semaphore with priority inheritance
enabled from the interrupt context (remove nxsem_restore_baseprio_irq())
Assert in nxsem_post if:
- Priority inheritance is enabled on a semaphore
- A thread that does not hold the semaphore attempts to post it
This will detect an error condition described in https://cwiki.apache.org/confluence/display/NUTTX/Signaling+Semaphores+and+Priority+Inheritance
None. The debug instrumentation is only enabled if CONFIG_DEBUG_ASSERTIONS is enabled.
Use sim:ostest. Verify that no assertions occur.
sem_t is user memory and the correct mappings are needed to perform
the semaphore wait interruption.
Otherwise either a page fault, or access to the WRONG address environment
happens.
NuttX kernel should not use the syscall functions, especially after
enabling CONFIG_SCHED_INSTRUMENTATION_SYSCALL, all system functions
will be traced to backend, which will impact system performance.
Signed-off-by: chao an <anchao@xiaomi.com>
It takes about 10 cycles to obtain the task list according to the task
status. In most cases, we know the task status, so we can directly
add the task from the specified task list to reduce time consuming.
It takes about 10 cycles to obtain the task list according to the task
status. In most cases, we know the task status, so we can directly
delete the task from the specified task list to reduce time consuming.
This commit is intended to solve the bug caused by #7159.
It will fixed data abort issue when task restart in wait sem status.
If delete waitobj in the sem recover function, then we will get the wrong
task list when remove the task from task list.
State of problem:
- Some drivers that do not support write operations (does not
have write handler or ioctl do not perform any write actions)
are registered with write permissions
- Some drivers that do not support read operation (does not
have read handler or ioctl do not perform any read actions)
are registered with read permissions
- Some drivers are registered with execute permissions
Solution:
- Iterate code where register_driver() is used and change 'mode'
parameter to reflect the actual read/write operations executed
by a driver
- Remove execute permissions from 'mode' parameter
Signed-off-by: Petro Karashchenko <petro.karashchenko@gmail.com>
1. The task which called nxsem_release_holder may not be a holder of the semaphore,
counts of the holder would not be decreamented.
This commit try to resolve the problem if there is only one holder.
2. Avoid counts overflow.
Signed-off-by: Zeng Zhaoxiu <walker.zeng@transtekcorp.com>
Add a list in TCB to track all semphores the task held, so we
can release all holders when exit, so nxsched_verify_tcb
is unnecessary.
Signed-off-by: Zeng Zhaoxiu <walker.zeng@transtekcorp.com>
There is a potential problem that can lead to deadlock at
condition wait, if the timeout of watchdog is a very small value
(1 tick ?), the timer interrupt will come before the nxsem_wait()
Revert "sched: pthread: Remove a redundant critical section in pthread_condclockwsait.c"
Revert "sched: semaphore: Remove a redundant critical section in nxsem_clockwait()"
Revert "sched: semaphore: Remove a redundant critical section in nxsem_tickwait()"
This reverts commit 7758f3dcb1.
This reverts commit 2976bb212e.
This reverts commit 65dec5d10a.
Signed-off-by: chao.an <anchao@xiaomi.com>
zhangyuan21