18 Feb, 2009

1 commit

  • …git/tip/linux-2.6-tip

    * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
    x86, vm86: fix preemption bug
    x86, olpc: fix model detection without OFW
    x86, hpet: fix for LS21 + HPET = boot hang
    x86: CPA avoid repeated lazy mmu flush
    x86: warn if arch_flush_lazy_mmu_cpu is called in preemptible context
    x86/paravirt: make arch_flush_lazy_mmu/cpu disable preemption
    x86, pat: fix warn_on_once() while mapping 0-1MB range with /dev/mem
    x86/cpa: make sure cpa is safe to call in lazy mmu mode
    x86, ptrace, mm: fix double-free on race

    Linus Torvalds
     

11 Feb, 2009

1 commit

  • Ptrace_detach() races with __ptrace_unlink() if the traced task is
    reaped while detaching. This might cause a double-free of the BTS
    buffer.

    Change the ptrace_detach() path to only do the memory accounting in
    ptrace_bts_detach() and leave the buffer free to ptrace_bts_untrace()
    which will be called from __ptrace_unlink().

    The fix follows a proposal from Oleg Nesterov.

    Reported-by: Oleg Nesterov
    Signed-off-by: Markus Metzger
    Signed-off-by: Ingo Molnar

    Markus Metzger
     

09 Feb, 2009

1 commit

  • Commit 27421e211a39784694b597dbf35848b88363c248, Manually revert
    "mlock: downgrade mmap sem while populating mlocked regions", has
    introduced its own regression: __mlock_vma_pages_range() may report
    an error (for example, -EFAULT from trying to lock down pages from
    beyond EOF), but mlock_vma_pages_range() must hide that from its
    callers as before.

    Reported-by: Sami Farin
    Signed-off-by: Hugh Dickins
    Cc: stable@kernel.org
    Signed-off-by: Linus Torvalds

    Hugh Dickins
     

02 Feb, 2009

1 commit

  • This essentially reverts commit 8edb08caf68184fb170f4f69c7445929e199eaea.

    It downgraded our mmap semaphore to a read-lock while mlocking pages, in
    order to allow other threads (and external accesses like "ps" et al) to
    walk the vma lists and take page faults etc. Which is a nice idea, but
    the implementation does not work.

    Because we cannot upgrade the lock back to a write lock without
    releasing the mmap semaphore, the code had to release the lock entirely
    and then re-take it as a writelock. However, that meant that the caller
    possibly lost the vma chain that it was following, since now another
    thread could come in and mmap/munmap the range.

    The code tried to work around that by just looking up the vma again and
    erroring out if that happened, but quite frankly, that was just a buggy
    hack that doesn't actually protect against anything (the other thread
    could just have replaced the vma with another one instead of totally
    unmapping it).

    The only way to downgrade to a read map _reliably_ is to do it at the
    end, which is likely the right thing to do: do all the 'vma' operations
    with the write-lock held, then downgrade to a read after completing them
    all, and then do the "populate the newly mlocked regions" while holding
    just the read lock. And then just drop the read-lock and return to user
    space.

    The (perhaps somewhat simpler) alternative is to just make all the
    callers of mlock_vma_pages_range() know that the mmap lock got dropped,
    and just re-grab the mmap semaphore if it needs to mlock more than one
    vma region.

    So we can do this "downgrade mmap sem while populating mlocked regions"
    thing right, but the way it was done here was absolutely not correct.
    Thus the revert, in the expectation that we will do it all correctly
    some day.

    Cc: Lee Schermerhorn
    Cc: Rik van Riel
    Cc: Andrew Morton
    Cc: stable@kernel.org
    Signed-off-by: Linus Torvalds

    Linus Torvalds
     

14 Jan, 2009

2 commits


07 Jan, 2009

1 commit

  • The initial implementation of checking TIF_MEMDIE covers the cases of OOM
    killing. If the process has been OOM killed, the TIF_MEMDIE is set and it
    return immediately. This patch includes:

    1. add the case that the SIGKILL is sent by user processes. The
    process can try to get_user_pages() unlimited memory even if a user
    process has sent a SIGKILL to it(maybe a monitor find the process
    exceed its memory limit and try to kill it). In the old
    implementation, the SIGKILL won't be handled until the get_user_pages()
    returns.

    2. change the return value to be ERESTARTSYS. It makes no sense to
    return ENOMEM if the get_user_pages returned by getting a SIGKILL
    signal. Considering the general convention for a system call
    interrupted by a signal is ERESTARTNOSYS, so the current return value
    is consistant to that.

    Lee:

    An unfortunate side effect of "make-get_user_pages-interruptible" is that
    it prevents a SIGKILL'd task from munlock-ing pages that it had mlocked,
    resulting in freeing of mlocked pages. Freeing of mlocked pages, in
    itself, is not so bad. We just count them now--altho' I had hoped to
    remove this stat and add PG_MLOCKED to the free pages flags check.

    However, consider pages in shared libraries mapped by more than one task
    that a task mlocked--e.g., via mlockall(). If the task that mlocked the
    pages exits via SIGKILL, these pages would be left mlocked and
    unevictable.

    Proposed fix:

    Add another GUP flag to ignore sigkill when calling get_user_pages from
    munlock()--similar to Kosaki Motohiro's 'IGNORE_VMA_PERMISSIONS flag for
    the same purpose. We are not actually allocating memory in this case,
    which "make-get_user_pages-interruptible" intends to avoid. We're just
    munlocking pages that are already resident and mapped, and we're reusing
    get_user_pages() to access those pages.

    ?? Maybe we should combine 'IGNORE_VMA_PERMISSIONS and '_IGNORE_SIGKILL
    into a single flag: GUP_FLAGS_MUNLOCK ???

    [Lee.Schermerhorn@hp.com: ignore sigkill in get_user_pages during munlock]
    Signed-off-by: Paul Menage
    Signed-off-by: Ying Han
    Reviewed-by: KOSAKI Motohiro
    Reviewed-by: Pekka Enberg
    Cc: Nick Piggin
    Cc: Hugh Dickins
    Cc: Oleg Nesterov
    Cc: Lee Schermerhorn
    Cc: Rohit Seth
    Cc: David Rientjes
    Signed-off-by: Lee Schermerhorn
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ying Han
     

20 Dec, 2008

1 commit

  • Impact: move the BTS buffer accounting to the mlock bucket

    Add alloc_locked_buffer() and free_locked_buffer() functions to mm/mlock.c
    to kalloc a buffer and account the locked memory to current.

    Account the memory for the BTS buffer to the tracer.

    Signed-off-by: Markus Metzger
    Signed-off-by: Ingo Molnar

    Markus Metzger
     

17 Nov, 2008

1 commit

  • Fix an unitialized return value when compiling on parisc (with CONFIG_UNEVICTABLE_LRU=y):
    mm/mlock.c: In function `__mlock_vma_pages_range':
    mm/mlock.c:165: warning: `ret' might be used uninitialized in this function

    Signed-off-by: Helge Deller
    [ It isn't ever really used uninitialized, since no caller should ever
    call this function with an empty range. But the compiler is correct
    that from a local analysis standpoint that is impossible to see, and
    fixing the warning is appropriate. ]
    Signed-off-by: Linus Torvalds

    Helge Deller
     

13 Nov, 2008

1 commit

  • lockdep warns about following message at boot time on one of my test
    machine. Then, schedule_on_each_cpu() sholdn't be called when the task
    have mmap_sem.

    Actually, lru_add_drain_all() exist to prevent the unevictalble pages
    stay on reclaimable lru list. but currenct unevictable code can rescue
    unevictable pages although it stay on reclaimable list.

    So removing is better.

    In addition, this patch add lru_add_drain_all() to sys_mlock() and
    sys_mlockall(). it isn't must. but it reduce the failure of moving to
    unevictable list. its failure can rescue in vmscan later. but reducing
    is better.

    Note, if above rescuing happend, the Mlocked and the Unevictable field
    mismatching happend in /proc/meminfo. but it doesn't cause any real
    trouble.

    =======================================================
    [ INFO: possible circular locking dependency detected ]
    2.6.28-rc2-mm1 #2
    -------------------------------------------------------
    lvm/1103 is trying to acquire lock:
    (&cpu_hotplug.lock){--..}, at: [] get_online_cpus+0x29/0x50

    but task is already holding lock:
    (&mm->mmap_sem){----}, at: [] sys_mlockall+0x4e/0xb0

    which lock already depends on the new lock.

    the existing dependency chain (in reverse order) is:

    -> #3 (&mm->mmap_sem){----}:
    [] check_noncircular+0x82/0x110
    [] might_fault+0x4a/0xa0
    [] validate_chain+0xb11/0x1070
    [] might_fault+0x4a/0xa0
    [] __lock_acquire+0x263/0xa10
    [] lock_acquire+0x7c/0xb0 (*) grab mmap_sem
    [] might_fault+0x4a/0xa0
    [] might_fault+0x7b/0xa0
    [] might_fault+0x4a/0xa0
    [] copy_to_user+0x30/0x60
    [] filldir+0x7c/0xd0
    [] sysfs_readdir+0x11a/0x1f0 (*) grab sysfs_mutex
    [] filldir+0x0/0xd0
    [] filldir+0x0/0xd0
    [] vfs_readdir+0x86/0xa0 (*) grab i_mutex
    [] sys_getdents+0x6b/0xc0
    [] syscall_call+0x7/0xb
    [] 0xffffffff

    -> #2 (sysfs_mutex){--..}:
    [] check_noncircular+0x82/0x110
    [] sysfs_addrm_start+0x2c/0xc0
    [] validate_chain+0xb11/0x1070
    [] sysfs_addrm_start+0x2c/0xc0
    [] __lock_acquire+0x263/0xa10
    [] lock_acquire+0x7c/0xb0 (*) grab sysfs_mutex
    [] sysfs_addrm_start+0x2c/0xc0
    [] mutex_lock_nested+0xa5/0x2f0
    [] sysfs_addrm_start+0x2c/0xc0
    [] sysfs_addrm_start+0x2c/0xc0
    [] sysfs_addrm_start+0x2c/0xc0
    [] create_dir+0x3f/0x90
    [] sysfs_create_dir+0x29/0x50
    [] _spin_unlock+0x25/0x40
    [] kobject_add_internal+0xcd/0x1a0
    [] kobject_set_name_vargs+0x3a/0x50
    [] kobject_init_and_add+0x2d/0x40
    [] sysfs_slab_add+0xd2/0x180
    [] sysfs_add_func+0x0/0x70
    [] sysfs_add_func+0x5c/0x70 (*) grab slub_lock
    [] run_workqueue+0x172/0x200
    [] run_workqueue+0x10f/0x200
    [] worker_thread+0x0/0xf0
    [] worker_thread+0x9c/0xf0
    [] autoremove_wake_function+0x0/0x50
    [] worker_thread+0x0/0xf0
    [] kthread+0x42/0x70
    [] kthread+0x0/0x70
    [] kernel_thread_helper+0x7/0x1c
    [] 0xffffffff

    -> #1 (slub_lock){----}:
    [] check_noncircular+0xd/0x110
    [] slab_cpuup_callback+0x11f/0x1d0
    [] validate_chain+0xb11/0x1070
    [] slab_cpuup_callback+0x11f/0x1d0
    [] mark_lock+0x35d/0xd00
    [] __lock_acquire+0x263/0xa10
    [] lock_acquire+0x7c/0xb0
    [] slab_cpuup_callback+0x11f/0x1d0
    [] down_read+0x43/0x80
    [] slab_cpuup_callback+0x11f/0x1d0 (*) grab slub_lock
    [] slab_cpuup_callback+0x11f/0x1d0
    [] notifier_call_chain+0x3c/0x70
    [] _cpu_up+0x84/0x110
    [] cpu_up+0x4b/0x70 (*) grab cpu_hotplug.lock
    [] kernel_init+0x0/0x170
    [] kernel_init+0xb5/0x170
    [] kernel_init+0x0/0x170
    [] kernel_thread_helper+0x7/0x1c
    [] 0xffffffff

    -> #0 (&cpu_hotplug.lock){--..}:
    [] validate_chain+0x5af/0x1070
    [] dev_status+0x0/0x50
    [] __lock_acquire+0x263/0xa10
    [] lock_acquire+0x7c/0xb0
    [] get_online_cpus+0x29/0x50
    [] mutex_lock_nested+0xa5/0x2f0
    [] get_online_cpus+0x29/0x50
    [] get_online_cpus+0x29/0x50
    [] lru_add_drain_per_cpu+0x0/0x10
    [] get_online_cpus+0x29/0x50 (*) grab cpu_hotplug.lock
    [] schedule_on_each_cpu+0x32/0xe0
    [] __mlock_vma_pages_range+0x85/0x2c0
    [] __lock_acquire+0x285/0xa10
    [] vma_merge+0xa9/0x1d0
    [] mlock_fixup+0x180/0x200
    [] do_mlockall+0x78/0x90 (*) grab mmap_sem
    [] sys_mlockall+0x81/0xb0
    [] syscall_call+0x7/0xb
    [] 0xffffffff

    other info that might help us debug this:

    1 lock held by lvm/1103:
    #0: (&mm->mmap_sem){----}, at: [] sys_mlockall+0x4e/0xb0

    stack backtrace:
    Pid: 1103, comm: lvm Not tainted 2.6.28-rc2-mm1 #2
    Call Trace:
    [] print_circular_bug_tail+0x7c/0xd0
    [] validate_chain+0x5af/0x1070
    [] dev_status+0x0/0x50
    [] __lock_acquire+0x263/0xa10
    [] lock_acquire+0x7c/0xb0
    [] get_online_cpus+0x29/0x50
    [] mutex_lock_nested+0xa5/0x2f0
    [] get_online_cpus+0x29/0x50
    [] get_online_cpus+0x29/0x50
    [] lru_add_drain_per_cpu+0x0/0x10
    [] get_online_cpus+0x29/0x50
    [] schedule_on_each_cpu+0x32/0xe0
    [] __mlock_vma_pages_range+0x85/0x2c0
    [] __lock_acquire+0x285/0xa10
    [] vma_merge+0xa9/0x1d0
    [] mlock_fixup+0x180/0x200
    [] do_mlockall+0x78/0x90
    [] sys_mlockall+0x81/0xb0
    [] syscall_call+0x7/0xb

    Signed-off-by: KOSAKI Motohiro
    Tested-by: Kamalesh Babulal
    Cc: Lee Schermerhorn
    Cc: Christoph Lameter
    Cc: Heiko Carstens
    Cc: Nick Piggin
    Cc: Hugh Dickins
    Cc: Rik van Riel
    Cc: Peter Zijlstra
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    KOSAKI Motohiro
     

20 Oct, 2008

5 commits

  • Rework Posix error return for mlock().

    Posix requires error code for mlock*() system calls for some conditions
    that differ from what kernel low level functions, such as
    get_user_pages(), return for those conditions. For more info, see:

    http://marc.info/?l=linux-kernel&m=121750892930775&w=2

    This patch provides the same translation of get_user_pages()
    error codes to posix specified error codes in the context
    of the mlock rework for unevictable lru.

    [akpm@linux-foundation.org: fix build]
    Signed-off-by: KOSAKI Motohiro
    Signed-off-by: Lee Schermerhorn
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Lee Schermerhorn
     
  • Add NR_MLOCK zone page state, which provides a (conservative) count of
    mlocked pages (actually, the number of mlocked pages moved off the LRU).

    Reworked by lts to fit in with the modified mlock page support in the
    Reclaim Scalability series.

    [kosaki.motohiro@jp.fujitsu.com: fix incorrect Mlocked field of /proc/meminfo]
    [lee.schermerhorn@hp.com: mlocked-pages: add event counting with statistics]
    Signed-off-by: Nick Piggin
    Signed-off-by: Lee Schermerhorn
    Signed-off-by: Rik van Riel
    Signed-off-by: KOSAKI Motohiro
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Nick Piggin
     
  • Originally by Nick Piggin

    Remove mlocked pages from the LRU using "unevictable infrastructure"
    during mmap(), munmap(), mremap() and truncate(). Try to move back to
    normal LRU lists on munmap() when last mlocked mapping removed. Remove
    PageMlocked() status when page truncated from file.

    [akpm@linux-foundation.org: cleanup]
    [kamezawa.hiroyu@jp.fujitsu.com: fix double unlock_page()]
    [kosaki.motohiro@jp.fujitsu.com: split LRU: munlock rework]
    [lee.schermerhorn@hp.com: mlock: fix __mlock_vma_pages_range comment block]
    [akpm@linux-foundation.org: remove bogus kerneldoc token]
    Signed-off-by: Nick Piggin
    Signed-off-by: Lee Schermerhorn
    Signed-off-by: Rik van Riel
    Signed-off-by: KOSAKI Motohiro
    Signed-off-by: KAMEZAWA Hiroyuki
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Rik van Riel
     
  • We need to hold the mmap_sem for write to initiatate mlock()/munlock()
    because we may need to merge/split vmas. However, this can lead to very
    long lock hold times attempting to fault in a large memory region to mlock
    it into memory. This can hold off other faults against the mm
    [multithreaded tasks] and other scans of the mm, such as via /proc. To
    alleviate this, downgrade the mmap_sem to read mode during the population
    of the region for locking. This is especially the case if we need to
    reclaim memory to lock down the region. We [probably?] don't need to do
    this for unlocking as all of the pages should be resident--they're already
    mlocked.

    Now, the caller's of the mlock functions [mlock_fixup() and
    mlock_vma_pages_range()] expect the mmap_sem to be returned in write mode.
    Changing all callers appears to be way too much effort at this point.
    So, restore write mode before returning. Note that this opens a window
    where the mmap list could change in a multithreaded process. So, at least
    for mlock_fixup(), where we could be called in a loop over multiple vmas,
    we check that a vma still exists at the start address and that vma still
    covers the page range [start,end). If not, we return an error, -EAGAIN,
    and let the caller deal with it.

    Return -EAGAIN from mlock_vma_pages_range() function and mlock_fixup() if
    the vma at 'start' disappears or changes so that the page range
    [start,end) is no longer contained in the vma. Again, let the caller deal
    with it. Looks like only sys_remap_file_pages() [via mmap_region()]
    should actually care.

    With this patch, I no longer see processes like ps(1) blocked for seconds
    or minutes at a time waiting for a large [multiple gigabyte] region to be
    locked down. However, I occassionally see delays while unlocking or
    unmapping a large mlocked region. Should we also downgrade the mmap_sem
    for the unlock path?

    Signed-off-by: Lee Schermerhorn
    Signed-off-by: Rik van Riel
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Lee Schermerhorn
     
  • Make sure that mlocked pages also live on the unevictable LRU, so kswapd
    will not scan them over and over again.

    This is achieved through various strategies:

    1) add yet another page flag--PG_mlocked--to indicate that
    the page is locked for efficient testing in vmscan and,
    optionally, fault path. This allows early culling of
    unevictable pages, preventing them from getting to
    page_referenced()/try_to_unmap(). Also allows separate
    accounting of mlock'd pages, as Nick's original patch
    did.

    Note: Nick's original mlock patch used a PG_mlocked
    flag. I had removed this in favor of the PG_unevictable
    flag + an mlock_count [new page struct member]. I
    restored the PG_mlocked flag to eliminate the new
    count field.

    2) add the mlock/unevictable infrastructure to mm/mlock.c,
    with internal APIs in mm/internal.h. This is a rework
    of Nick's original patch to these files, taking into
    account that mlocked pages are now kept on unevictable
    LRU list.

    3) update vmscan.c:page_evictable() to check PageMlocked()
    and, if vma passed in, the vm_flags. Note that the vma
    will only be passed in for new pages in the fault path;
    and then only if the "cull unevictable pages in fault
    path" patch is included.

    4) add try_to_unlock() to rmap.c to walk a page's rmap and
    ClearPageMlocked() if no other vmas have it mlocked.
    Reuses as much of try_to_unmap() as possible. This
    effectively replaces the use of one of the lru list links
    as an mlock count. If this mechanism let's pages in mlocked
    vmas leak through w/o PG_mlocked set [I don't know that it
    does], we should catch them later in try_to_unmap(). One
    hopes this will be rare, as it will be relatively expensive.

    Original mm/internal.h, mm/rmap.c and mm/mlock.c changes:
    Signed-off-by: Nick Piggin

    splitlru: introduce __get_user_pages():

    New munlock processing need to GUP_FLAGS_IGNORE_VMA_PERMISSIONS.
    because current get_user_pages() can't grab PROT_NONE pages theresore it
    cause PROT_NONE pages can't munlock.

    [akpm@linux-foundation.org: fix this for pagemap-pass-mm-into-pagewalkers.patch]
    [akpm@linux-foundation.org: untangle patch interdependencies]
    [akpm@linux-foundation.org: fix things after out-of-order merging]
    [hugh@veritas.com: fix page-flags mess]
    [lee.schermerhorn@hp.com: fix munlock page table walk - now requires 'mm']
    [kosaki.motohiro@jp.fujitsu.com: build fix]
    [kosaki.motohiro@jp.fujitsu.com: fix truncate race and sevaral comments]
    [kosaki.motohiro@jp.fujitsu.com: splitlru: introduce __get_user_pages()]
    Signed-off-by: KOSAKI Motohiro
    Signed-off-by: Rik van Riel
    Signed-off-by: Lee Schermerhorn
    Cc: Nick Piggin
    Cc: Dave Hansen
    Cc: Matt Mackall
    Signed-off-by: Hugh Dickins
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Nick Piggin
     

05 Aug, 2008

1 commit

  • Halesh says:

    Please find the below testcase provide to test mlock.

    Test Case :
    ===========================

    #include
    #include
    #include
    #include
    #include
    #include
    #include
    #include
    #include

    int main(void)
    {
    int fd,ret, i = 0;
    char *addr, *addr1 = NULL;
    unsigned int page_size;
    struct rlimit rlim;

    if (0 != geteuid())
    {
    printf("Execute this pgm as root\n");
    exit(1);
    }

    /* create a file */
    if ((fd = open("mmap_test.c",O_RDWR|O_CREAT,0755)) == -1)
    {
    printf("cant create test file\n");
    exit(1);
    }

    page_size = sysconf(_SC_PAGE_SIZE);

    /* set the MEMLOCK limit */
    rlim.rlim_cur = 2000;
    rlim.rlim_max = 2000;

    if ((ret = setrlimit(RLIMIT_MEMLOCK,&rlim)) != 0)
    {
    printf("Cant change limit values\n");
    exit(1);
    }

    addr = 0;
    while (1)
    {
    /* map a page into memory each time*/
    if ((addr = (char *) mmap(addr,page_size, PROT_READ |
    PROT_WRITE,MAP_SHARED,fd,0)) == MAP_FAILED)
    {
    printf("cant do mmap on file\n");
    exit(1);
    }

    if (0 == i)
    addr1 = addr;
    i++;
    errno = 0;
    /* lock the mapped memory pagewise*/
    if ((ret = mlock((char *)addr, 1500)) == -1)
    {
    printf("errno value is %d\n", errno);
    printf("cant lock maped region\n");
    exit(1);
    }
    addr = addr + page_size;
    }
    }
    ======================================================

    This testcase results in an mlock() failure with errno 14 that is EFAULT,
    but it has nowhere been specified that mlock() will return EFAULT. When I
    tested the same on older kernels like 2.6.18, I got the correct result i.e
    errno 12 (ENOMEM).

    I think in source code mlock(2), setting errno ENOMEM has been missed in
    do_mlock() , on mlock_fixup() failure.

    SUSv3 requires the following behavior frmo mlock(2).

    [ENOMEM]
    Some or all of the address range specified by the addr and
    len arguments does not correspond to valid mapped pages
    in the address space of the process.

    [EAGAIN]
    Some or all of the memory identified by the operation could not
    be locked when the call was made.

    This rule isn't so nice and slighly strange. but many people think
    POSIX/SUS compliance is important.

    Reported-by: Halesh Sadashiv
    Tested-by: Halesh Sadashiv
    Signed-off-by: KOSAKI Motohiro
    Cc: [2.6.25.x, 2.6.26.x]
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    KOSAKI Motohiro
     

17 Jul, 2007

1 commit


22 May, 2007

1 commit

  • First thing mm.h does is including sched.h solely for can_do_mlock() inline
    function which has "current" dereference inside. By dealing with can_do_mlock()
    mm.h can be detached from sched.h which is good. See below, why.

    This patch
    a) removes unconditional inclusion of sched.h from mm.h
    b) makes can_do_mlock() normal function in mm/mlock.c
    c) exports can_do_mlock() to not break compilation
    d) adds sched.h inclusions back to files that were getting it indirectly.
    e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
    getting them indirectly

    Net result is:
    a) mm.h users would get less code to open, read, preprocess, parse, ... if
    they don't need sched.h
    b) sched.h stops being dependency for significant number of files:
    on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
    after patch it's only 3744 (-8.3%).

    Cross-compile tested on

    all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
    alpha alpha-up
    arm
    i386 i386-up i386-defconfig i386-allnoconfig
    ia64 ia64-up
    m68k
    mips
    parisc parisc-up
    powerpc powerpc-up
    s390 s390-up
    sparc sparc-up
    sparc64 sparc64-up
    um-x86_64
    x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig

    as well as my two usual configs.

    Signed-off-by: Alexey Dobriyan
    Signed-off-by: Linus Torvalds

    Alexey Dobriyan
     

08 Dec, 2006

1 commit


12 Jan, 2006

1 commit

  • - Move capable() from sched.h to capability.h;

    - Use where capable() is used
    (in include/, block/, ipc/, kernel/, a few drivers/,
    mm/, security/, & sound/;
    many more drivers/ to go)

    Signed-off-by: Randy Dunlap
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Randy.Dunlap
     

17 Apr, 2005

1 commit

  • 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!

    Linus Torvalds