1. 07 Dec, 2006 1 commit
  2. 26 Sep, 2006 2 commits
  3. 30 Jun, 2006 6 commits
  4. 27 Mar, 2006 1 commit
  5. 30 Oct, 2005 2 commits
    • Dave Hansen's avatar
      [PATCH] memory hotplug locking: node_size_lock · 208d54e5
      Dave Hansen authored
      pgdat->node_size_lock is basically only neeeded in one place in the normal
      code: show_mem(), which is the arch-specific sysrq-m printing function.
      Strictly speaking, the architectures not doing memory hotplug do no need this
      locking in show_mem().  However, they are all included for completeness.  This
      should also make any future consolidation of all of the implementations a
      little more straightforward.
      This lock is also held in the sparsemem code during a memory removal, as
      sections are invalidated.  This is the place there pfn_valid() is made false
      for a memory area that's being removed.  The lock is only required when doing
      pfn_valid() operations on memory which the user does not already have a
      reference on the page, such as in show_mem().
      Signed-off-by: default avatarDave Hansen <haveblue@us.ibm.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
    • Hugh Dickins's avatar
      [PATCH] mm: split page table lock · 4c21e2f2
      Hugh Dickins authored
      Christoph Lameter demonstrated very poor scalability on the SGI 512-way, with
      a many-threaded application which concurrently initializes different parts of
      a large anonymous area.
      This patch corrects that, by using a separate spinlock per page table page, to
      guard the page table entries in that page, instead of using the mm's single
      page_table_lock.  (But even then, page_table_lock is still used to guard page
      table allocation, and anon_vma allocation.)
      In this implementation, the spinlock is tucked inside the struct page of the
      page table page: with a BUILD_BUG_ON in case it overflows - which it would in
      the case of 32-bit PA-RISC with spinlock debugging enabled.
      Splitting the lock is not quite for free: another cacheline access.  Ideally,
      I suppose we would use split ptlock only for multi-threaded processes on
      multi-cpu machines; but deciding that dynamically would have its own costs.
      So for now enable it by config, at some number of cpus - since the Kconfig
      language doesn't support inequalities, let preprocessor compare that with
      NR_CPUS.  But I don't think it's worth being user-configurable: for good
      testing of both split and unsplit configs, split now at 4 cpus, and perhaps
      change that to 8 later.
      There is a benefit even for singly threaded processes: kswapd can be attacking
      one part of the mm while another part is busy faulting.
      Signed-off-by: default avatarHugh Dickins <hugh@veritas.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
  6. 05 Sep, 2005 1 commit
    • Zachary Amsden's avatar
      [PATCH] i386: encapsulate copying of pgd entries · d7271b14
      Zachary Amsden authored
      Add a clone operation for pgd updates.
      This helps complete the encapsulation of updates to page tables (or pages
      about to become page tables) into accessor functions rather than using
      memcpy() to duplicate them.  This is both generally good for consistency
      and also necessary for running in a hypervisor which requires explicit
      updates to page table entries.
      The new function is:
      clone_pgd_range(pgd_t *dst, pgd_t *src, int count);
         dst - pointer to pgd range anwhere on a pgd page
         src - ""
         count - the number of pgds to copy.
         dst and src can be on the same page, but the range must not overlap
         and must not cross a page boundary.
      Note that I ommitted using this call to copy pgd entries into the
      software suspend page root, since this is not technically a live paging
      structure, rather it is used on resume from suspend.  CC'ing Pavel in case
      he has any feedback on this.
      Thanks to Chris Wright for noticing that this could be more optimal in
      PAE compiles by eliminating the memset.
      Signed-off-by: default avatarZachary Amsden <zach@vmware.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
  7. 25 Jun, 2005 1 commit
  8. 23 Jun, 2005 2 commits
    • Martin J. Bligh's avatar
      [PATCH] add page_state info to show_mem · 6f4e1e50
      Martin J. Bligh authored
      This helps a lot when debugging out of memory stuff - useful especially to
      see if all the memory is sucked into slab, etc.
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
    • Dave Hansen's avatar
      [PATCH] remove non-DISCONTIG use of pgdat->node_mem_map · 408fde81
      Dave Hansen authored
      This patch effectively eliminates direct use of pgdat->node_mem_map outside
      of the DISCONTIG code.  On a flat memory system, these fields aren't
      currently used, neither are they on a sparsemem system.
      There was also a node_mem_map(nid) macro on many architectures.  Its use
      along with the use of ->node_mem_map itself was not consistent.  It has
      been removed in favor of two new, more explicit, arch-independent macros:
      	pgdat_page_nr(pgdat, pagenr)
      	nid_page_nr(nid, pagenr)
      I called them "pgdat" and "nid" because we overload the term "node" to mean
      "NUMA node", "DISCONTIG node" or "pg_data_t" in very confusing ways.  I
      believe the newer names are much clearer.
      These macros can be overridden in the sparsemem case with a theoretically
      slower operation using node_start_pfn and pfn_to_page(), instead.  We could
      make this the only behavior if people want, but I don't want to change too
      much at once.  One thing at a time.
      This patch removes more code than it adds.
      Compile tested on alpha, alpha discontig, arm, arm-discontig, i386, i386
      generic, NUMAQ, Summit, ppc64, ppc64 discontig, and x86_64.  Full list
      here: http://sr71.net/patches/2.6.12/2.6.12-rc1-mhp2/configs/
      Boot tested on NUMAQ, x86 SMP and ppc64 power4/5 LPARs.
      Signed-off-by: default avatarDave Hansen <haveblue@us.ibm.com>
      Signed-off-by: default avatarMartin J. Bligh <mbligh@aracnet.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
  9. 19 Apr, 2005 1 commit
    • Hugh Dickins's avatar
      [PATCH] freepgt: free_pgtables use vma list · e0da382c
      Hugh Dickins authored
      Recent woes with some arches needing their own pgd_addr_end macro; and 4-level
      clear_page_range regression since 2.6.10's clear_page_tables; and its
      long-standing well-known inefficiency in searching throughout the higher-level
      page tables for those few entries to clear and free: all can be blamed on
      ignoring the list of vmas when we free page tables.
      Replace exit_mmap's clear_page_range of the total user address space by
      free_pgtables operating on the mm's vma list; unmap_region use it in the same
      way, giving floor and ceiling beyond which it may not free tables.  This
      brings lmbench fork/exec/sh numbers back to 2.6.10 (unless preempt is enabled,
      in which case latency fixes spoil unmap_vmas throughput).
      Beware: the do_mmap_pgoff driver failure case must now use unmap_region
      instead of zap_page_range, since a page table might have been allocated, and
      can only be freed while it is touched by some vma.
      Move free_pgtables from mmap.c to memory.c, where its lower levels are adapted
      from the clear_page_range levels.  (Most of free_pgtables' old code was
      actually for a non-existent case, prev not properly set up, dating from before
      hch gave us split_vma.) Pass mmu_gather** in the public interfaces, since we
      might want to add latency lockdrops later; but no attempt to do so yet, going
      by vma should itself reduce latency.
      But what if is_hugepage_only_range?  Those ia64 and ppc64 cases need careful
      examination: put that off until a later patch of the series.
      What of x86_64's 32bit vdso page __map_syscall32 maps outside any vma?
      And the range to sparc64's flush_tlb_pgtables?  It's less clear to me now that
      we need to do more than is done here - every PMD_SIZE ever occupied will be
      flushed, do we really have to flush every PGDIR_SIZE ever partially occupied? 
      A shame to complicate it unnecessarily.
      Special thanks to David Miller for time spent repairing my ceilings.
      Signed-off-by: default avatarHugh Dickins <hugh@veritas.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
  10. 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!