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2007-01-29Richard Sandiford writes:Mike Frysinger
However, retesting on m68k showed up a problem that had appeared in uClibc since the last time I tried. Specifically, revision 15785 did: -#define HEAP_GRANULARITY (sizeof (HEAP_GRANULARITY_TYPE)) +#define HEAP_GRANULARITY (__alignof__ (HEAP_GRANULARITY_TYPE)) -#define MALLOC_ALIGNMENT (sizeof (double)) +#define MALLOC_ALIGNMENT (__alignof__ (double)) The problem is that (a) MALLOC_HEADER_SIZE == MALLOC_ALIGNMENT (b) the header contains a size value of type size_t (c) sizeof (size_t) is 4 on m68k, but... (d) __alignof__ (double) is only 2 (the largest alignment used on m68k) So we only allocate 2 bytes for the 4-byte header, and the least significant 2 bytes of the size are in the user's area rather than the header. The patch below fixes that problem by redefining MALLOC_HEADER_SIZE to: MAX (MALLOC_ALIGNMENT, sizeof (size_t)) (but without the help of the MAX macro ;)). However, we really would like to have word alignment on Coldfire. It makes a big performance difference, and because we have to allocate a 4-byte header anyway, what wastage there is will be confined to the end of the allocated block. Any wastage will also be limited to 2 bytes per allocation compared to the current alignment. I've therefore used the __aligned__ type attribute to create a double type that has at least sizeof (size_t) bytes of alignment. I've introduced a new __attribute_aligned__ macro for this. It might seem silly protecting against old or non-GNU compilers here, but the extra alignment is only an optimisation, and having the macro is more in the spirit of the other attribute code.
2006-12-11mostly revert the locking changes for 'malloc', as the implementationEric Andersen
does not easily lend itself to becoming complete pthread cancelation safe without first investing in some deep and serious thought... The other malloc implementations are pthread cancelation safe, and this one is mostly used for uClinux, where the lack is at least less likely to be a common problem.
2006-12-07Major cleanup of internal mutex locking. Be more consistant in how we doEric Andersen
things, and avoid potential deadlocks caused when a thread holding a uClibc internal lock get canceled and terminates without releasing the lock. This change also provides a single place, bits/uClibc_mutex.h, for thread libraries to modify to change all instances of internal locking.
2006-08-05merge fix from blackfin cvs:Mike Frysinger
bernds writes: Use __alignof__ instead of sizeof to get alignments. Eliminates some warnings about misalignments when malloc debugging is enabled.
2005-12-06macro out the thread funcs in libc if threading is disabledMike Frysinger
2003-12-27Fix a long-standing bug with pthreads. A couple of linuxthreads filesManuel Novoa III
were including libc-lock.h which had a bunch of weak pragmas. Also, uClibc supplied a number of no-op weak thread functions even though many weren't needed. This combined result was that sometimes the functional versions of thread functions in pthread would not override the weaks in libc. While fixing this, I also prepended double-underscore to all necessary weak thread funcs in uClibc, and removed all unused weaks. I did a test build, but haven't tested this since these changes are a backport from my working tree. I did test the changes there and no longer need to explicitly add -lpthread in the perl build for perl to pass its thread self tests.
2003-09-22More fiddling with static free-areas: make sure both their size _and_Miles Bader
their alignment are correct.
2003-09-19Make sure we don't allocate too little space for static free-areasMiles Bader
because of our fiddling with alignment (because doing so is VERY BAD).
2003-09-17Make sure static heaps are aligned correctly.Miles Bader
2003-09-06'extern inline' doesn't work... Use 'static inline'Eric Andersen
2002-10-17Fix malloc so it compiles and works when using pthreadsEric Andersen
-Erik
2002-10-09* Add support for uClinux's broken munmap, contingent onMiles Bader
__UCLIBC_UCLINUX_BROKEN_MUNMAP__ (which is currently not defined anywhere). This makes other cases a tiny bit less efficient too. * Move the malloc lock into the heap structure (locking is still done at the malloc level though, not by the heap functions). * Initialize the malloc heap to contain a tiny initial static free-area so that programs that only do a very little allocation won't ever call mmap.
2002-09-06Update debugging hooks.Miles Bader
2002-09-04(__heap_delete): Renamed from `__heap_unlink_free_area'.Miles Bader
(__heap_free_area_alloc): Use __heap_delete. (__heap_is_empty): New macro.
2002-08-30(likely, unlikely): New macros.Miles Bader
2002-08-01(HEAP_MIN_SIZE): New macro.Miles Bader
(HEAP_MIN_FREE_AREA_SIZE): Increase size. Enable debugging if HEAP_DEBUGGING is defined.
2002-07-25Redo the locking, so that it may actually work. Now locking is done atMiles Bader
the malloc/free level, not within the heap abstraction, and there's a separate lock to control sbrk access. Also, get rid of the separate `unmap_free_area' function in free.c, and just put the code in the `free' function directly, which saves a bunch of space (even compared to using an inline function) for some reason.
2002-07-24Factor out some common code sequences into inline functions.Miles Bader
2002-07-23* Automatically try to unmap heap free-areas when they get very big.Miles Bader
* Instead of using mmap/munmap directly for large allocations, just use the heap for everything (this is reasonable now that heap memory can be unmapped). * Use sbrk instead of mmap/munmap on systems with an MMU.
2002-07-19Rename mutex stuff to use heap-specific names.Miles Bader
Doc fix.
2002-07-18Miles Bader implemented a new mmap based malloc which is muchEric Andersen
smarter than the old "malloc-simple", and actually works, unlike the old "malloc". So kill the old "malloc-simple" and the old "malloc" and replace them with Miles' new malloc implementation. Update Config files to match. Thanks Miles!