This change introduce 2 items:
1. If the size of the space requested is 0, the behavior is implementation-defined:
either a null pointer shall be returned, or the behavior shall be as if the size
were some non-zero value, except that the behavior is undefined if the returned
pointer is used to access an object.
Change the behavior to be similar to Linux and Android and allocates an object
of a minimum size instead of returning null pointer.
https://pubs.opengroup.org/onlinepubs/9699919799/functions/malloc.htmlhttps://pubs.opengroup.org/onlinepubs/9699919799/functions/calloc.htmlhttps://pubs.opengroup.org/onlinepubs/9699919799/functions/realloc.html
2. The description of realloc() has been modified from previous versions of this
standard to align with the ISO/IEC 9899:1999 standard. Previous versions explicitly
permitted a call to realloc (p, 0) to free the space pointed to by p and return
a null pointer. While this behavior could be interpreted as permitted by this
version of the standard, the C language committee have indicated that this
interpretation is incorrect. Applications should assume that if realloc() returns
a null pointer, the space pointed to by p has not been freed. Since this could lead
to double-frees, implementations should also set errno if a null pointer actually
indicates a failure, and applications should only free the space if errno was changed.
Do not free memory of zero-length reallocation is requested
https://pubs.opengroup.org/onlinepubs/9699919799/functions/realloc.html
Co-authored-by: fangxinyong <fangxinyong@xiaomi.com>
Signed-off-by: Petro Karashchenko <petro.karashchenko@gmail.com>
There are many small memory block in NuttX system, eg: struct tcb_s,
struct inode, etc, and several disadvantages about them:
1.Their frequent allocate and free cause the system memory fragmentation.
2.Since each memory block has an overhead, the utilization of small memory
blocks is relatively low, which will cause memory waste.
So we can use mempool to alloc smallo block, to improve alloc speed
and utilization, to reduce fragmentation.
Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>
The return value of function mm_takesemaphore will never below
than zero, DEBUGVERIFY make no effect to check it, use DEBUGASSERT
instead.
Signed-off-by: xiangdong6 <xiangdong6@xiaomi.com>
When allocation failed, it isn't too uncommon for the caller
to fall back to other allocation method.
(eg. esp32 textheap code tries iram heap when an allocation from rtc heap
failed.)
DEBUGASSERT(false) is too much in that case.
This commit removes the DEBUGASSERT, and also makes the heap dump
a separate option.
usage:
echo <pid/used/free> trace > /proc/memdump
echo used > /proc/memdump //output all used memory info with backtrace
echo free > /proc/memdump //output all free memory info
echo 22 > /proc/memdump //output used memory info for task pid is 22 with backtrace
Signed-off-by: Jiuzhu Dong <dongjiuzhu1@xiaomi.com>
1.Move all special process to mm_takesemaphore
2.Remove the support of recurive lock
3.Remove mm_trysemaphore function
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: Ie216a6294ab67c5d427f31b089beb15c532f08fe
it's more simple to make mm_heap_s opaque outside of mm
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: I5c8e435f6baba6d22b10c5f7e8d9191104fb5af2
Root casue:
when do thread exit, need add free stack operation to mm_delaylist,
but in SMP mode, CPU0 thread1 exit, at this time, CPU1 call malloc
and free mm_delaylist.
Fix:
Divide mm_delaylist for per CPU in SMP mode.
Change-Id: Ibf7d04614ea2f99fb5b506356b7346a0d94f0590
Signed-off-by: ligd <liguiding1@xiaomi.com>
Pullreq libc libnx updates
* NuttX: make strerror() return 'Success' for 0
* NuttX: fix strrchr() so that it considers null terminator as part of string
From strrchr(3) man page:
"The terminating null byte is considered part of the string, so that if c
is specified as '\0', these functions return a pointer to the terminator."
* NuttX: mm_free(): Add DEBUGASSERT()'s to catch memory corruption early.
It's easier to find the source when asserts fail already when freeing
an overflowed buffer, than if the corruption is only detected on next
malloc().
* MM_FILL_ALLOCATIONS: Add debug option to fill all mallocs()
This is helpful for detecting uninitialized variables,
especially in C++ code. I seem to be forgetting to initialize
member variables and then they just get random values..
* NuttX: nxtk_bitmapwindow: Fix warning message when bitmap is fully off-screen.
* nxfonts_getfont: Avoid unnecessary warnings for other whitespace chars also.
* NuttX: Fix kerning of 'I' in Sans17x22 font
The I character was running together with some other
characters, e.g. in sequence "IMI".
* NXMU: Revalidate window pointer for mouse events.
NXMU caches the previous window pointer so that further mouse
events can be sent to the same window. However, if the window
is destroyed while mouse button is held down, the pointer may
become invalid and cause a crash. This patch revalidates the
pointer before using it.
Approved-by: GregoryN <gnutt@nuttx.org>
