u-boot/common/dlmalloc.src

183      very small chunks.
266     Because freed chunks may be overwritten with link fields, this
595   int ordblks;  /* number of non-inuse chunks */
634       afterward allocate more large chunks) the value should be high
654       program undergoes phases where several large chunks are
657       chunks at all.  And in well-behaved long-lived programs,
721       Using mmap segregates relatively large chunks of memory so that
731       other chunks, as can happen with normally allocated chunks, which
737 	    used to service later requests, as happens with normal chunks.
1150     Chunks of memory are maintained using a `boundary tag' method as
1153     survey of such techniques.)  Sizes of free chunks are stored both
1155     consolidating fragmented chunks into bigger chunks very fast.  The
1156     size fields also hold bits representing whether chunks are free or
1180     Chunks always begin on even word boundries, so the mem portion
1184     Free chunks are stored in circular doubly-linked lists, and look like this:
1223      2. Chunks allocated via mmap, which have the second-lowest-order
1228     Available chunks are kept in any of several places (all declared below):
1230     * `av': An array of chunks serving as bin headers for consolidated
1231        chunks. Each bin is doubly linked.  The bins are approximately
1235        consolidated chunk physically borders another one. Chunks in
1239        The chunks in each bin are maintained in decreasing sorted order by
1241        the same-sized chunks, but facilitates best-fit allocation for
1242        larger chunks. (These lists are just sequential. Keeping them in
1244        fancier ordered data structures.)  Chunks of the same size are
1248        consolidated with adjacent freed chunks, resulting in larger free
1249        chunks and less fragmentation.
1259        before other non-fitting chunks, so as to provide better
1260        locality for runs of sequentially allocated chunks.
1400     heads of (initially empty) doubly-linked lists of chunks, laid out
1403     and chunks are the same).
1405     Bins for sizes < 512 bytes contain chunks of all the same size, spaced
1423     The special chunks `top' and `last_remainder' get their own bins,
1503   bins for chunks < 512 are all spaced 8 bytes apart, and hold
1504   identically sized chunks. This is exploited in malloc.
1659   /* ... and is surrounded by OK chunks.
1660     Since more things can be checked with free chunks than inuse ones,
1725   Linking chunks in bin lists.
1811   /* For mmapped chunks, the overhead is one SIZE_SZ unit larger, because
2061 	 allocation strategy tends to give contiguous chunks
2087 	 units) in a way that allows chunks obtained across different
2355        4. Other chunks are consolidated as they arrive, and
2462     Chunks that were obtained via mmap cannot be extended or shrunk
2927     locked between two used chunks, so they cannot be given back to
3221       * Use best fit for very large chunks to prevent some worst-cases.
3225       * Removed footers when chunks are in use. Thanks to
3240       * Occasionally bin return list chunks in first scan
3247       * Scan 2 returns chunks (not just 1)