* Simplify EINTR/ECANCEL error handling
1. Add semaphore uninterruptible wait function
2 .Replace semaphore wait loop with a single uninterruptible wait
3. Replace all sem_xxx to nxsem_xxx
* Unify the void cast usage
1. Remove void cast for function because many place ignore the returned value witout cast
2. Replace void cast for variable with UNUSED macro
libs/: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
syscall/: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
wireless/: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
Documentation/: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
include/: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
drivers/: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
sched/: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
configs: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
arch/xtensa: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
arch/z80: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
arch/x86: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
arch/renesas and arch/risc-v: Remove references to CONFIG_DISABLE_SIGNALS. Signals can no longer be disabled.
arch/or1k: Remove all references to CONFIG_DISABLE_SIGNALS. Signals are always enabled.
arch/misoc: Remove all references to CONFIG_DISABLE_SIGNALS. Signals are always enabled.
arch/mips: Remove all references to CONFIG_DISABLE_SIGNALS. Signals are always enabled.
arch/avr: Remove all references to CONFIG_DISABLE_SIGNALS. Signals are always enabled.
arch/arm: Remove all references to CONFIG_DISABLE_SIGNALS. Signals are always enabled.
Squashed commit of the following:
Trivial, cosmetic
sched/, arch/, and include: Rename task_vforkstart() as nxtask_vforkstart()
sched/, arch/, and include: Rename task_vforkabort() as nxtask_vforkabort()
sched/, arch/, and include: Rename task_vforksetup() as nxtask_vfork_setup()
sched/: Rename notify_cancellation() as nxnotify_cancellation()
sched/: Rename task_recover() to nxtask_recover()
sched/task, sched/pthread/, Documentation/: Rename task_argsetup() and task_terminate() to nxtask_argsetup() and nxtask_terminate(), respectively.
sched/task: Rename task_schedsetup() to nxtask_schedsetup()
sched/ (plus some binfmt/, include/, and arch/): Rename task_start() and task_starthook() to nxtask_start() and nxtask_starthook().
arch/ and sched/: Rename task_exit() and task_exithook() to nxtask_exit() and nxtask_exithook(), respectively.
sched/task: Rename all internal, static, functions to begin with the nx prefix.
This is analogous to similar renaming that was done previously for semaphores.
Squashed commit of the following:
sched/signal: Fix a few compile warnings introduced by naming changes.
sched/signal: Rename all private, internal signl functions to use the nxsig_ prefix.
sched/signal: Rename sig_removependingsignal, sig_unmaskpendingsignal, and sig_mqnotempty to nxsig_remove_pendingsignal, nxsig_unmask_pendingsignal, and nxsig_mqnotempty to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_findaction and sig_lowest to nxsig_find_action and nxsig_lowest to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_allocatepingsigaction and sig_deliver to nxsig_alloc_pendingsigaction and nxsig_deliver to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_cleanup, sig_release, sig_releasependingaction, and sig_releasependingsignal to nxsig_cleanup, nxsig_release, nxsig_release_pendingaction, and nxsig_release_pendingsignal to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_tcbdispatch and sig_dispatch to nxsig_tcbdispatch and nxsig_dispatch to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_releaseaction and sig_pendingset to nxsig_release_action and nxsig_pendingset to make it clear that these are OS internal interfaces.
sched/signal: Rename sig_initialize and sig_allocateactionblock to nxsig_initialize and nxsig_alloc_actionblock to make it clear that these are OS internal interfaces.
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.
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.
