On 01.08.23 18:02, Sean Anderson wrote:
On 8/1/23 03:04, Heinrich Schuchardt wrote:
On 8/1/23 00:33, Sean Anderson wrote:
When we enable malloc_init, there is no need to statically initialize av_, since we are going to do it manually. This lets us move av_ to .bss, saving around 1-2k of data (depending on the pointer size).
cALLOc must be adjusted to not access top before malloc_init.
While we're at it, rename/reword the Kconfig to better describe what this option does.
Signed-off-by: Sean Anderson sean.anderson@seco.com
Kconfig | 18 +++++++----------- common/dlmalloc.c | 9 +++++++-- 2 files changed, 14 insertions(+), 13 deletions(-)
diff --git a/Kconfig b/Kconfig index 70efb41cc6..4b32286b69 100644 --- a/Kconfig +++ b/Kconfig @@ -372,18 +372,14 @@ if EXPERT When disabling this, please check if malloc calls, maybe should be replaced by calloc - if one expects zeroed memory. -config SYS_MALLOC_DEFAULT_TO_INIT - bool "Default malloc to init while reserving the memory for it" +config SYS_MALLOC_RUNTIME_INIT + bool "Initialize malloc's internal data at runtime" help - It may happen that one needs to move the dynamic allocation - from one to another memory range, eg. when moving the malloc - from the limited static to a potentially large dynamic (DDR) - memory.
- If so then on top of setting the updated memory aside one - needs to bring the malloc init.
- If such a scenario is sought choose yes. + Initialize malloc's internal data structures at runtime, rather than + at compile-time. This is necessary if relocating the malloc arena + from a smaller static memory to a large DDR memory. It can also + reduce the size of U-Boot by letting malloc's data reside in .bss + instead of .data. config TOOLS_DEBUG bool "Enable debug information for tools" diff --git a/common/dlmalloc.c b/common/dlmalloc.c index 30c78ae976..8a1daae5ec 100644 --- a/common/dlmalloc.c +++ b/common/dlmalloc.c @@ -556,6 +556,7 @@ typedef struct malloc_chunk* mbinptr; #define IAV(i) bin_at(i), bin_at(i) static mbinptr av_[NAV * 2 + 2] = { +#if !CONFIG_IS_ENABLED(SYS_MALLOC_RUNTIME_INIT) NULL, NULL, IAV(0), IAV(1), IAV(2), IAV(3), IAV(4), IAV(5), IAV(6), IAV(7), IAV(8), IAV(9), IAV(10), IAV(11), IAV(12), IAV(13), IAV(14), IAV(15), @@ -573,6 +574,7 @@ static mbinptr av_[NAV * 2 + 2] = { IAV(104), IAV(105), IAV(106), IAV(107), IAV(108), IAV(109), IAV(110), IAV(111), IAV(112), IAV(113), IAV(114), IAV(115), IAV(116), IAV(117), IAV(118), IAV(119), IAV(120), IAV(121), IAV(122), IAV(123), IAV(124), IAV(125), IAV(126), IAV(127) +#endif };
With this patch booting qemu-riscv64_spl_defconfig with SYS_MALLOC_RUNTIME_INIT=y fails without output from main U-Boot.
After removing the #if above, main U-Boot output provides some output but driver binding fails.
Without this patch and with SYS_MALLOC_DEFAULT_TO_INIT=y booting succeeds.
#ifdef CONFIG_NEEDS_MANUAL_RELOC @@ -623,7 +625,7 @@ void mem_malloc_init(ulong start, ulong size) mem_malloc_end = start + size; mem_malloc_brk = start; - if (CONFIG_IS_ENABLED(SYS_MALLOC_DEFAULT_TO_INIT)) + if (CONFIG_IS_ENABLED(SYS_MALLOC_RUNTIME_INIT)) malloc_init(); debug("using memory %#lx-%#lx for malloc()\n", mem_malloc_start, @@ -2151,7 +2153,10 @@ Void_t* cALLOc(n, elem_size) size_t n; size_t elem_size; #ifdef CONFIG_SYS_MALLOC_CLEAR_ON_INIT #if MORECORE_CLEARS mchunkptr oldtop = top; - INTERNAL_SIZE_T oldtopsize = chunksize(top); + INTERNAL_SIZE_T oldtopsize; + if (CONFIG_IS_ENABLED(SYS_MALLOC_RUNTIME_INIT) && + !(gd->flags & GD_FLG_FULL_MALLOC_INIT)) + oldtopsize = chunksize(top);
malloc_simple needs a value for oldtopsize and this is before GD_FLG_FULL_MALLOC_INIT is set.
This change worked for me:
#ifdef CONFIG_SYS_MALLOC_CLEAR_ON_INIT #if MORECORE_CLEARS mchunkptr oldtop = top; if (CONFIG_IS_ENABLED(SYS_MALLOC_RUNTIME_INIT) && !(gd->flags & GD_FLG_FULL_MALLOC_INIT)) malloc_init(); INTERNAL_SIZE_T oldtopsize = chunksize(top); #endif #endif
You don't want to call malloc_init() twice. So some flag should be added indicating if malloc_init() has been invoked.
Actually, I think the original condition was just backwards. It should be
if (!CONFIG_IS_ENABLED(SYS_MALLOC_RUNTIME_INIT) && (gd->flags & GD_FLG_FULL_MALLOC_INIT))
This does not work either.
oldtopsize is needed in calloc() both w/ and w/o GD_FLG_FULL_MALLOC_INIT and w/ and w/o SYS_MALLOC_RUNTIME_INIT to define the memory area to zero out for calloc(). You must set it to the correct value irrespective of these conditions.
Why don't you want to call malloc_init() here?
Best regards
Heinrich
although this still doesn't match the malloc_simple condition. So maybe the condition to remove the initialization should be
#if !CONFIG_VAL(SYS_MALLOC_F_LEN) && \ !CONFIG_IS_ENABLED(SYS_MALLOC_RUNTIME_INIT)
or perhaps RUNTIME_INIT should depend on F_LEN? I don't see anyone using for other purposes, so I think adding this dependency should be fine.
--Sean