The standard describes trylock as follows, trylock should never cause the system to stop running:
The pthread_mutex_trylock() function shall be equivalent to
pthread_mutex_lock(), except that if the mutex object referenced by
mutex is currently locked (by any thread, including the current thread),
the call shall return immediately.
https://linux.die.net/man/3/pthread_mutex_trylock
Signed-off-by: yinshengkai <yinshengkai@xiaomi.com>
Summary:
If we disable LIB_PATHBUFFER_MALLOC, that when the path buffer is insufficient, NULL is returned to avoid applying for a buffer from the heap.
Signed-off-by: chenrun1 <chenrun1@xiaomi.com>
Summary:
Since there is a default definition for CONFIG_SMP_NCPUS in sys/types.h, we can remove #ifdef and return CONFIG_SMP_NCPUS directly.
Signed-off-by: chenrun1 <chenrun1@xiaomi.com>
Summary:
1.Remove the macro definition of getnproc in sysinfo
2.New get_nprocs_conf and get_nprocs interfaces, return CONFIG_SMP_NCPUS, return 1 when not defined
Signed-off-by: chenrun1 <chenrun1@xiaomi.com>
This is a tool for associating discrete IDs with addresses.
This tool is implemented through the red-black tree method provided by <sys/tree.h>, and the time complexity when calling, searching, and deleting is optimized to O(logn)
The implementation is the moving node operation of two red-black trees
1. When applying for a node, it will first check whether there is an available node in the "removed" tree. If so, the memory address of the node will be reused and moved to the "alloced" tree.
2. If the "removed" tree is an "empty tree", then the node will be requested from the memory and added to the "alloced" tree
3. Similarly, when removing a node, we set the address pointed to in the node to "NULL" and move it to the "removed" tree. Next time we alloc the node, we can reduce the overhead caused by memory application
For now, we still have something that can be optimized, and that is the memory elimination mechanism of the "removed tree". The current implementation will only release all the content under the "removed" tree when the idtree is destroyed.
Signed-off-by: chenrun1 <chenrun1@xiaomi.com>
Add a common method to format backtrace to buffer, so it can be used by both mm, fs and other possoble modules.
Signed-off-by: fangpeina <fangpeina@xiaomi.com>
Don't include the build timestamp into final binary when the symbol
CONFIG_LIBC_UNAME_DISABLE_TIMESTAMP is defined.
Signed-off-by: Alan C. Assis <acassis@gmail.com>
Add registration function instrumentation API,
which can achieve instrumentation of entering and
exiting functions through the compiler's functionality.
We can use CONFIG_ARCH_INSTRUMENT_ALL to add instrumentation for all
source, or add '-finstrument-functions' to CFLAGS for Part of the
source.
Notice:
1. use CONFIG_ARCH_INSTRUMENT_ALL must mark _start or entry noinstrument_function,
becuase bss not set.
2. Make sure your callbacks are not instrumented recursively.
use instrument_register to register entry function and exit function.
They will be called by the instrumented function
Signed-off-by: anjiahao <anjiahao@xiaomi.com>
Binary nibble to/from ascii hex conversion was buggy on both
lib_slcdencode and lib_slcddecode libraries.
This bug caused the slcd library to fail to decode 5-byte sequence command
which have 'count' argument value bigger than 0x9.
Signed-off-by: Federico Braghiroli <federico.braghiroli@gmail.com>
This moves all the public POSIX semaphore functions into libc and with
this most of the user-space logic is also moved; namely cancel point and
errno handling.
This also removes the need for the _SEM_XX macros used to differentiate
which API is used per user-/kernel mode. Such macros are henceforth
unnecessary.
https://man7.org/linux/man-pages/man2/memfd_create.2.html:
The name supplied in name is used as a filename and will be
displayed as the target of the corresponding symbolic link in the
directory /proc/self/fd/. The displayed name is always prefixed
with memfd: and serves only for debugging purposes. Names do not
affect the behavior of the file descriptor, and as such multiple
files can have the same name without any side effects.
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
1. Update all CMakeLists.txt to adapt to new layout
2. Fix cmake build break
3. Update all new file license
4. Fully compatible with current compilation environment(use configure.sh or cmake as you choose)
------------------
How to test
From within nuttx/. Configure:
cmake -B build -DBOARD_CONFIG=sim/nsh -GNinja
cmake -B build -DBOARD_CONFIG=sim:nsh -GNinja
cmake -B build -DBOARD_CONFIG=sabre-6quad/smp -GNinja
cmake -B build -DBOARD_CONFIG=lm3s6965-ek/qemu-flat -GNinja
(or full path in custom board) :
cmake -B build -DBOARD_CONFIG=$PWD/boards/sim/sim/sim/configs/nsh -GNinja
This uses ninja generator (install with sudo apt install ninja-build). To build:
$ cmake --build build
menuconfig:
$ cmake --build build -t menuconfig
--------------------------
2. cmake/build: reformat the cmake style by cmake-format
https://github.com/cheshirekow/cmake_format
$ pip install cmakelang
$ for i in `find -name CMakeLists.txt`;do cmake-format $i -o $i;done
$ for i in `find -name *\.cmake`;do cmake-format $i -o $i;done
Co-authored-by: Matias N <matias@protobits.dev>
Signed-off-by: chao an <anchao@xiaomi.com>
If cancellation points are enabled, then the following logic is activated in sem_wait(). This causes ECANCELED to be returned every time that sem_wait is called.
int sem_wait(FAR sem_t *sem)
{
...
/* sem_wait() is a cancellation point */
if (enter_cancellation_point())
{
#ifdef CONFIG_CANCELLATION_POINTS
/* If there is a pending cancellation, then do not perform
* the wait. Exit now with ECANCELED.
*/
errcode = ECANCELED;
goto errout_with_cancelpt;
#endif
}
...
Normally this works fine. sem_wait() is the OS API called by the application and will cancel the thread just before it returns to the application. Since it is cancellation point, it should never be called from within the OS.
There there is is one perverse cases where sem_wait() may be nested within another cancellation point. If open() is called, it will attempt to lock a VFS data structure and will eventually call nxmutex_lock(). nxmutex_lock() waits on a semaphore:
int nxmutex_lock(FAR mutex_t *mutex)
{
...
for (; ; )
{
/* Take the semaphore (perhaps waiting) */
ret = _SEM_WAIT(&mutex->sem);
if (ret >= 0)
{
mutex->holder = _SCHED_GETTID();
break;
}
ret = _SEM_ERRVAL(ret);
if (ret != -EINTR && ret != -ECANCELED)
{
break;
}
}
...
}
In the FLAT build, _SEM_WAIT expands to sem_wait(). That causes the error in the logic: It should always expand to nxsem_wait(). That is because sem_wait() is cancellation point and should never be called from with the OS or the C library internally.
The failure occurs because the cancellation point logic in sem_wait() returns -ECANCELED (via _SEM_ERRVAL) because sem_wait() is nested; it needs to return the -ECANCELED error to the outermost cancellation point which is open() in this case. Returning -ECANCELED then causes an infinite loop to occur in nxmutex_lock().
The correct behavior in this case is to call nxsem_wait() instead of sem_wait(). nxsem_wait() is identical to sem_wait() except that it is not a cancelation point. It will return -ECANCELED if the thread is canceled, but only once. So no infinite loop results.
In addition, an nxsem_wait() system call was added to support the call from nxmutex_lock().
This resolves Issue #9695
In many cases, it is legal for the child process to use the fd
created by the parent process,
so to improve compatibility, we allow the child process
to use the fd of the Parent process.
Signed-off-by: hujun5 <hujun5@xiaomi.com>
In embedded development environments, due to the lack of address isolation between processes,
fd may be passed between processes and lead to misuse,
We have designed an fd cross-process automatic detection tool,
fdcheck_protect returns the fd containing the pid information,
indicating that the ownership of the current fd belongs to the pid and is not allowed to be used by other processes.
fdcheck_restore will obtain the true fd and check if the ownership of the fd is legal
For ease of understanding, let's give an example where
the following information is represented in 32-bit binary format
fd 00000000 00000000 00000000 10001010
pid 00000000 00000000 00000011 01010101
ret 00000000 00000011 01010101 10001010
Signed-off-by: hujun5 <hujun5@xiaomi.com>
FD (file descriptor) is widely used in system software development,
and almost all implementations of posix os (including nuttx) use FD as an index.
the value of fd needs to be allocated starting from the minimum available value of 3, and each process has a copy,
so the same fd value is very easy to reuse in the program.
In multi threaded or multi process environments without address isolation,
If the ownership, global variables, and competition relationships of fd are not properly handled,
there may be issues with fd duplication or accidental closure.
Further leading to the following issues, which are difficult to troubleshoot.
1. Security vulnerability: the fd we wrote is not the expected fd and will be accessed by hackers to obtain data
2. Program exceptions or crashes: write or read fd failures, and program logic errors
3. The structured file XML or database is damaged: the data format written to the database is not the expected format.
The implementation principle of fdsan is based on the implementation of Android
https://android.googlesource.com/platform/bionic/+/master/docs/fdsan.md
Signed-off-by: hujun5 <hujun5@xiaomi.com>
sim/rpserver
NuttShell (NSH) NuttX-12.0.0
server> cu
_assert: Current Version: NuttX server 12.0.0 3ead669e7a-dirty Feb 2 2023 23:53:48 sim
_assert: Assertion failed : at file: libs/libc/misc/lib_mutex.c:303 task: cu 0x5662fff4
Signed-off-by: chao an <anchao@xiaomi.com>
Petro Karashchenko