Re: wkspace failed allocations with heap protection enabled
On Wed, Apr 13, 2022 at 10:51 AM Matthew J Fletcher wrote: > Hi Joel, > > Works fine without debug, its the deferred free doing _Heap_Allocate with > the negative size thats causing it. > Glad that workaround gets you by it. Please do file a ticket though. :) --joel > > > On Wed, 13 Apr 2022 at 16:09, Joel Sherrill wrote: > >> This appears to be a bad side-effect of the way the deferred free is >> implemented >> when the memory protection/fence is enabled. This is turned on by >> enabling >> rtems debug. >> >> I'd recommend filing a ticket and assigning it to Sebastian for a real >> fix. >> >> In the meantime, see if building RTEMS without debug enabled helps. >> >> --joel >> >> On Wed, Apr 13, 2022 at 4:30 AM Matthew J Fletcher >> wrote: >> >>> Hi, >>> >>> Investigating the "Total number of failed allocations:" from the >>> wkspace cmd i see that; >>> >>> /* Statistics */ >>> ++stats->failed_allocs; >>> >>> Are incremented when _Heap_Allocate_aligned_with_boundary fails, however >>> it >>> seems this will routinely fail due to; >>> >>> _Heap_Protection_free_all_delayed_blocks seemingly on purpose creating an >>> impossibly large allocation. >>> >>> uintptr_t large = 0 >>> - (uintptr_t) HEAP_BLOCK_HEADER_SIZE >>> - (uintptr_t) HEAP_ALLOC_BONUS >>> - (uintptr_t) 1; >>> >>> void *p = _Heap_Allocate( heap, large ); >>> >>> This makes it difficult to place a breakpoint on failed_allocs to >>> investigate true low memory situations with heap protection enabled. >>> >>> >>> regards >>> --- >>> Matthew J Fletcher >>> ___ >>> users mailing list >>> users@rtems.org >>> http://lists.rtems.org/mailman/listinfo/users >>> >> > > -- > > regards > --- > Matthew J Fletcher > > ___ users mailing list users@rtems.org http://lists.rtems.org/mailman/listinfo/users
Re: wkspace failed allocations with heap protection enabled
This appears to be a bad side-effect of the way the deferred free is implemented when the memory protection/fence is enabled. This is turned on by enabling rtems debug. I'd recommend filing a ticket and assigning it to Sebastian for a real fix. In the meantime, see if building RTEMS without debug enabled helps. --joel On Wed, Apr 13, 2022 at 4:30 AM Matthew J Fletcher wrote: > Hi, > > Investigating the "Total number of failed allocations:" from the > wkspace cmd i see that; > > /* Statistics */ > ++stats->failed_allocs; > > Are incremented when _Heap_Allocate_aligned_with_boundary fails, however it > seems this will routinely fail due to; > > _Heap_Protection_free_all_delayed_blocks seemingly on purpose creating an > impossibly large allocation. > > uintptr_t large = 0 > - (uintptr_t) HEAP_BLOCK_HEADER_SIZE > - (uintptr_t) HEAP_ALLOC_BONUS > - (uintptr_t) 1; > > void *p = _Heap_Allocate( heap, large ); > > This makes it difficult to place a breakpoint on failed_allocs to > investigate true low memory situations with heap protection enabled. > > > regards > --- > Matthew J Fletcher > ___ > users mailing list > users@rtems.org > http://lists.rtems.org/mailman/listinfo/users > ___ users mailing list users@rtems.org http://lists.rtems.org/mailman/listinfo/users
Re: get_heap_info memsets stats element
On Wed, Apr 13, 2022 at 8:32 AM Matthew J Fletcher wrote: > Hi, > > _Heap_Get_information provides the information but its then memset after > retrieval, is this a bug or design ? > > _Heap_Get_information(heap, info); > memset(>Stats, 0, sizeof(info->Stats)); > In this case, this call is in support of resource snapshot. This is used in tests to ensure the number of objects/allocations is the same before and after a test case is executed. It verifies no leaks. The stats section has the number of calls, maximum memory allocated, etc. and would legitimately change. By zero'ing it out, it makes it possible to compare the before and after versions. Would be good to have a comment here explaining that. Patch welcome. :_ --joel > > -- > > regards > --- > Matthew J Fletcher > ___ > users mailing list > users@rtems.org > http://lists.rtems.org/mailman/listinfo/users > ___ users mailing list users@rtems.org http://lists.rtems.org/mailman/listinfo/users
get_heap_info memsets stats element
Hi, _Heap_Get_information provides the information but its then memset after retrieval, is this a bug or design ? _Heap_Get_information(heap, info); memset(>Stats, 0, sizeof(info->Stats)); -- regards --- Matthew J Fletcher ___ users mailing list users@rtems.org http://lists.rtems.org/mailman/listinfo/users
wkspace failed allocations with heap protection enabled
Hi, Investigating the "Total number of failed allocations:" from the wkspace cmd i see that; /* Statistics */ ++stats->failed_allocs; Are incremented when _Heap_Allocate_aligned_with_boundary fails, however it seems this will routinely fail due to; _Heap_Protection_free_all_delayed_blocks seemingly on purpose creating an impossibly large allocation. uintptr_t large = 0 - (uintptr_t) HEAP_BLOCK_HEADER_SIZE - (uintptr_t) HEAP_ALLOC_BONUS - (uintptr_t) 1; void *p = _Heap_Allocate( heap, large ); This makes it difficult to place a breakpoint on failed_allocs to investigate true low memory situations with heap protection enabled. regards --- Matthew J Fletcher ___ users mailing list users@rtems.org http://lists.rtems.org/mailman/listinfo/users
