1. 09 Jan, 2006 2 commits
    • Matt Mackall's avatar
      [PATCH] slob: introduce the SLOB allocator · 10cef602
      Matt Mackall authored
      configurable replacement for slab allocator
      This adds a CONFIG_SLAB option under CONFIG_EMBEDDED.  When CONFIG_SLAB is
      disabled, the kernel falls back to using the 'SLOB' allocator.
      SLOB is a traditional K&R/UNIX allocator with a SLAB emulation layer,
      similar to the original Linux kmalloc allocator that SLAB replaced.  It's
      signicantly smaller code and is more memory efficient.  But like all
      similar allocators, it scales poorly and suffers from fragmentation more
      than SLAB, so it's only appropriate for small systems.
      It's been tested extensively in the Linux-tiny tree.  I've also
      stress-tested it with make -j 8 compiles on a 3G SMP+PREEMPT box (not
      Here's a comparison for otherwise identical builds, showing SLOB saving
      nearly half a megabyte of RAM:
      $ size vmlinux*
         text    data     bss     dec     hex filename
      3336372  529360  190812 4056544  3de5e0 vmlinux-slab
      3323208  527948  190684 4041840  3dac70 vmlinux-slob
      $ size mm/{slab,slob}.o
         text    data     bss     dec     hex filename
        13221     752      48   14021    36c5 mm/slab.o
         1896      52       8    1956     7a4 mm/slob.o
                        SLAB          SLOB      delta
      MemTotal:        27964 kB      27980 kB     +16 kB
      MemFree:         24596 kB      25092 kB    +496 kB
      Buffers:            36 kB         36 kB       0 kB
      Cached:           1188 kB       1188 kB       0 kB
      SwapCached:          0 kB          0 kB       0 kB
      Active:            608 kB        600 kB      -8 kB
      Inactive:          808 kB        812 kB      +4 kB
      HighTotal:           0 kB          0 kB       0 kB
      HighFree:            0 kB          0 kB       0 kB
      LowTotal:        27964 kB      27980 kB     +16 kB
      LowFree:         24596 kB      25092 kB    +496 kB
      SwapTotal:           0 kB          0 kB       0 kB
      SwapFree:            0 kB          0 kB       0 kB
      Dirty:               4 kB         12 kB      +8 kB
      Writeback:           0 kB          0 kB       0 kB
      Mapped:            560 kB        556 kB      -4 kB
      Slab:             1756 kB          0 kB   -1756 kB
      CommitLimit:     13980 kB      13988 kB      +8 kB
      Committed_AS:     4208 kB       4208 kB       0 kB
      PageTables:         28 kB         28 kB       0 kB
      VmallocTotal:  1007312 kB    1007312 kB       0 kB
      VmallocUsed:        48 kB         48 kB       0 kB
      VmallocChunk:  1007264 kB    1007264 kB       0 kB
      (this work has been sponsored in part by CELF)
      From: Ingo Molnar <mingo@elte.hu>
         Fix 32-bitness bugs in mm/slob.c.
      Signed-off-by: default avatarMatt Mackall <mpm@selenic.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
    • Matt Mackall's avatar
      [PATCH] slob: introduce mm/util.c for shared functions · 30992c97
      Matt Mackall authored
      Add mm/util.c for functions common between SLAB and SLOB.
      Signed-off-by: default avatarMatt Mackall <mpm@selenic.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
  2. 30 Oct, 2005 1 commit
  3. 24 Jun, 2005 1 commit
    • Carsten Otte's avatar
      [PATCH] xip: fs/mm: execute in place · ceffc078
      Carsten Otte authored
      - generic_file* file operations do no longer have a xip/non-xip split
      - filemap_xip.c implements a new set of fops that require get_xip_page
        aop to work proper. all new fops are exported GPL-only (don't like to
        see whatever code use those except GPL modules)
      - __xip_unmap now uses page_check_address, which is no longer static
        in rmap.c, and defined in linux/rmap.h
      - mm/filemap.h is now much more clean, plainly having just Linus'
        inline funcs moved here from filemap.c
      - fix includes in filemap_xip to make it build cleanly on i386
      Signed-off-by: default avatarCarsten Otte <cotte@de.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
  4. 23 Jun, 2005 1 commit
    • Andy Whitcroft's avatar
      [PATCH] sparsemem memory model · d41dee36
      Andy Whitcroft authored
      Sparsemem abstracts the use of discontiguous mem_maps[].  This kind of
      mem_map[] is needed by discontiguous memory machines (like in the old
      CONFIG_DISCONTIGMEM case) as well as memory hotplug systems.  Sparsemem
      replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
      become a complete replacement.
      A significant advantage over DISCONTIGMEM is that it's completely separated
      from CONFIG_NUMA.  When producing this patch, it became apparent in that NUMA
      and DISCONTIG are often confused.
      Another advantage is that sparse doesn't require each NUMA node's ranges to be
      contiguous.  It can handle overlapping ranges between nodes with no problems,
      where DISCONTIGMEM currently throws away that memory.
      Sparsemem uses an array to provide different pfn_to_page() translations for
      each SECTION_SIZE area of physical memory.  This is what allows the mem_map[]
      to be chopped up.
      In order to do quick pfn_to_page() operations, the section number of the page
      is encoded in page->flags.  Part of the sparsemem infrastructure enables
      sharing of these bits more dynamically (at compile-time) between the
      page_zone() and sparsemem operations.  However, on 32-bit architectures, the
      number of bits is quite limited, and may require growing the size of the
      page->flags type in certain conditions.  Several things might force this to
      occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
      memory), an increase in the physical address space, or an increase in the
      number of used page->flags.
      One thing to note is that, once sparsemem is present, the NUMA node
      information no longer needs to be stored in the page->flags.  It might provide
      speed increases on certain platforms and will be stored there if there is
      room.  But, if out of room, an alternate (theoretically slower) mechanism is
      This patch introduces CONFIG_FLATMEM.  It is used in almost all cases where
      there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
      often have to compile out the same areas of code.
      Signed-off-by: default avatarAndy Whitcroft <apw@shadowen.org>
      Signed-off-by: default avatarDave Hansen <haveblue@us.ibm.com>
      Signed-off-by: default avatarMartin Bligh <mbligh@aracnet.com>
      Signed-off-by: default avatarAdrian Bunk <bunk@stusta.de>
      Signed-off-by: default avatarYasunori Goto <y-goto@jp.fujitsu.com>
      Signed-off-by: default avatarBob Picco <bob.picco@hp.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
  5. 16 Apr, 2005 1 commit
    • Linus Torvalds's avatar
      Linux-2.6.12-rc2 · 1da177e4
      Linus Torvalds authored
      Initial git repository build. I'm not bothering with the full history,
      even though we have it. We can create a separate "historical" git
      archive of that later if we want to, and in the meantime it's about
      3.2GB when imported into git - space that would just make the early
      git days unnecessarily complicated, when we don't have a lot of good
      infrastructure for it.
      Let it rip!