PR #11165 causes an unnecessary regression; task_delete no longer works,
if the deleted task is from another group.
The logic that prevents this comes from:
nxnotify_cancellation() ->
tls_get_info_pid() ->
nxsched_get_stackinfo()
Which checks for permissions, which does not make sense in this case since
it is the kernel asking for the stack information.
Fix this by partially reverting 11165 and implementing a direct path for
the kernel to query for any tasks TLS.
This moves task / thread cancel point logic from the NuttX kernel into
libc, while the data needed by the cancel point logic is moved to TLS.
The change is an enabler to move user-space APIs to libc as well, for
a coherent user/kernel separation.
Summary:
- In case of BUILD_KERNEL, NuttX uses USR mode sp and SVC mode sp.
- The kernel runs on SVC mode sp.
- While the kernel is running, up_getsp() cannot get the TLS address.
- The kernel requires tls_get_info() function.
- For the user land, up_getsp() can be used.
- tls_getinfo.c is always compiled and tls_get_info() function is
filtered by macros in the tls_getinfo.c.
Impact:
BUILD_KERNEL
Testing:
test program on custom Cortex-A9 board (BUILD_KERNEL)
ostest on sabre-6quad:smp (QEMU, BUILD_FLAT)
Signed-off-by: Oki Minabe <minabe.oki@gmail.com>
Fix comment in libs/libc/tls/tls_getinfo.c: The TLS data must lie at the beginning of the allocated stack memory for both push-up and push-down stacks.
1. Move pthread-specific data files from sched/pthread/ to libs/libc/pthread.
2. Remove pthread-specific data functions from syscalls.
3. Implement tls_alloc() and tls_free() with system calls.
4. Reimplement pthread_key_create() and pthread_key_free() using tls_alloc() and tls_free().
5. Reimplement pthread_set_specific() and pthread_get_specicif() using tls_set_value() and tls_get_value()
- Remove per-thread errno from the TCB structure (pterrno)
- Remove get_errno() and set_errno() as functions. The macros are still available as stubs and will be needed in the future if we need to access the errno from a different address environment (KERNEL mode).
- Add errno value to the tls_info_s structure definitions
- Move sched/errno to libs/libc/errno. Replace old TCB access to the errno with TLS access to the errno.
Move the logic to get TLS information from an inline function to a normal function. For the unaligned case, it is probably too large to be inlined.
Also fixes some minor things from review of previous commits.
