1. 10 4月, 2013 10 次提交
  2. 08 4月, 2013 1 次提交
  3. 18 3月, 2013 2 次提交
  4. 14 3月, 2013 3 次提交
    • A
      sched: Fix variable name misnomer, add comments · 1bf08230
      Andrei Epure 提交于
      The min_vruntime variable actually stores the maximum value.
      The added comment was taken from place_entity function.
      Signed-off-by: NAndrei Epure <epure.andrei@gmail.com>
      Cc: peterz@infradead.org
      Link: http://lkml.kernel.org/r/1363115544-1964-1-git-send-email-epure.andrei@gmail.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      1bf08230
    • F
      sched: Lower chances of cputime scaling overflow · d9a3c982
      Frederic Weisbecker 提交于
      Some users have reported that after running a process with
      hundreds of threads on intensive CPU-bound loads, the cputime
      of the group started to freeze after a few days.
      
      This is due to how we scale the tick-based cputime against
      the scheduler precise execution time value.
      
      We add the values of all threads in the group and we multiply
      that against the sum of the scheduler exec runtime of the whole
      group.
      
      This easily overflows after a few days/weeks of execution.
      
      A proposed solution to solve this was to compute that multiplication
      on stime instead of utime:
         62188451
         ("cputime: Avoid multiplication overflow on utime scaling")
      
      The rationale behind that was that it's easy for a thread to
      spend most of its time in userspace under intensive CPU-bound workload
      but it's much harder to do CPU-bound intensive long run in the kernel.
      
      This postulate got defeated when a user recently reported he was still
      seeing cputime freezes after the above patch. The workload that
      triggers this issue relates to intensive networking workloads where
      most of the cputime is consumed in the kernel.
      
      To reduce much more the opportunities for multiplication overflow,
      lets reduce the multiplication factors to the remainders of the division
      between sched exec runtime and cputime. Assuming the difference between
      these shouldn't ever be that large, it could work on many situations.
      
      This gets the same results as in the upstream scaling code except for
      a small difference: the upstream code always rounds the results to
      the nearest integer not greater to what would be the precise result.
      The new code rounds to the nearest integer either greater or not
      greater. In practice this difference probably shouldn't matter but
      it's worth mentioning.
      
      If this solution appears not to be enough in the end, we'll
      need to partly revert back to the behaviour prior to commit
           0cf55e1e
           ("sched, cputime: Introduce thread_group_times()")
      
      Back then, the scaling was done on exit() time before adding the cputime
      of an exiting thread to the signal struct. And then we'll need to
      scale one-by-one the live threads cputime in thread_group_cputime(). The
      drawback may be a slightly slower code on exit time.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Stanislaw Gruszka <sgruszka@redhat.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      d9a3c982
    • F
      math64: New div64_u64_rem helper · f7926850
      Frederic Weisbecker 提交于
      Provide an extended version of div64_u64() that
      also returns the remainder of the division.
      
      We are going to need this to refine the cputime
      scaling code.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Stanislaw Gruszka <sgruszka@redhat.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      f7926850
  5. 11 3月, 2013 2 次提交
  6. 08 3月, 2013 6 次提交
    • I
      Merge branch 'sched/cputime' of... · 4e3da467
      Ingo Molnar 提交于
      Merge branch 'sched/cputime' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into sched/core
      
      Pull cputime changes from Frederic Weisbecker:
      
        * Generalize exception handling
      
        * Fix race in context tracking state restore on return from exception
          and irq exit kernel preemption
      
        * Fix cputime scaling in full dynticks accounting dynamic off-case
      
        * Fix default Kconfig value
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      4e3da467
    • F
      context_tracking: Enable probes by default for selftesting · 8b438766
      Frederic Weisbecker 提交于
      Until we provide the nohz_mask boot parameter, keeping
      the context tracking probes disabled by default is pointless
      since what we want is to runtime test this code anyway.
      
      It's furthermore confusing for the users which don't expect
      the probes to be off when they select RCU user mode or full
      dynticks cputime accounting.
      
      Let's enable these probes selftests by default for now.
      
      Suggested: Steven Rostedt <rostedt@goodmis.org>
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Li Zhong <zhong@linux.vnet.ibm.com>
      Cc: Kevin Hilman <khilman@linaro.org>
      Cc: Mats Liljegren <mats.liljegren@enea.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Namhyung Kim <namhyung.kim@lge.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      8b438766
    • F
      cputime: Dynamically scale cputime for full dynticks accounting · 9fbc42ea
      Frederic Weisbecker 提交于
      The full dynticks cputime accounting is able to account either
      using the tick or the context tracking subsystem. This way
      the housekeeping CPU can keep the low overhead tick based
      solution.
      
      This latter mode has a low jiffies resolution granularity and
      need to be scaled against CFS precise runtime accounting to
      improve its result. We are doing this for CONFIG_TICK_CPU_ACCOUNTING,
      now we also need to expand it to full dynticks accounting dynamic
      off-case as well.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Li Zhong <zhong@linux.vnet.ibm.com>
      Cc: Kevin Hilman <khilman@linaro.org>
      Cc: Mats Liljegren <mats.liljegren@enea.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Namhyung Kim <namhyung.kim@lge.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      9fbc42ea
    • F
      context_tracking: Restore preempted context state after preempt_schedule_irq() · b22366cd
      Frederic Weisbecker 提交于
      From the context tracking POV, preempt_schedule_irq() behaves pretty much
      like an exception: It can be called anytime and schedule another task.
      
      But currently it doesn't restore the context tracking state of the preempted
      code on preempt_schedule_irq() return.
      
      As a result, if preempt_schedule_irq() is called in the tiny frame between
      user_enter() and the actual return to userspace, we resume userspace with
      the wrong context tracking state.
      
      Fix this by using exception_enter/exit() which are a perfect fit for this
      kind of issue.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Li Zhong <zhong@linux.vnet.ibm.com>
      Cc: Kevin Hilman <khilman@linaro.org>
      Cc: Mats Liljegren <mats.liljegren@enea.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Namhyung Kim <namhyung.kim@lge.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      b22366cd
    • F
      context_tracking: Restore correct previous context state on exception exit · 6c1e0256
      Frederic Weisbecker 提交于
      On exception exit, we restore the previous context tracking state based on
      the regs of the interrupted frame. Iff that frame is in user mode as
      stated by user_mode() helper, we restore the context tracking user mode.
      
      However there is a tiny chunck of low level arch code after we pass through
      user_enter() and until the CPU eventually resumes userspace.
      If an exception happens in this tiny area, exception_enter() correctly
      exits the context tracking user mode but exception_exit() won't restore
      it because of the value returned by user_mode(regs).
      
      As a result we may return to userspace with the wrong context tracking
      state.
      
      To fix this, change exception_enter() to return the context tracking state
      prior to its call and pass this saved state to exception_exit(). This restores
      the real context tracking state of the interrupted frame.
      
      (May be this patch was suggested to me, I don't recall exactly. If so,
      sorry for the missing credit).
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Li Zhong <zhong@linux.vnet.ibm.com>
      Cc: Kevin Hilman <khilman@linaro.org>
      Cc: Mats Liljegren <mats.liljegren@enea.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Namhyung Kim <namhyung.kim@lge.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      6c1e0256
    • F
      context_tracking: Move exception handling to generic code · 56dd9470
      Frederic Weisbecker 提交于
      Exceptions handling on context tracking should share common
      treatment: on entry we exit user mode if the exception triggered
      in that context. Then on exception exit we return to that previous
      context.
      
      Generalize this to avoid duplication across archs.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Li Zhong <zhong@linux.vnet.ibm.com>
      Cc: Kevin Hilman <khilman@linaro.org>
      Cc: Mats Liljegren <mats.liljegren@enea.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Namhyung Kim <namhyung.kim@lge.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      56dd9470
  7. 06 3月, 2013 9 次提交
  8. 04 3月, 2013 7 次提交
    • L
      Linux 3.9-rc1 · 6dbe51c2
      Linus Torvalds 提交于
      6dbe51c2
    • L
      Merge tag 'disintegrate-fbdev-20121220' of git://git.infradead.org/users/dhowells/linux-headers · ea882c2e
      Linus Torvalds 提交于
      Pull fbdev UAPI disintegration from David Howells:
       "You'll be glad to here that the end is nigh for the UAPI patches.
        Only the fbdev/framebuffer piece remains now that the SCSI stuff has
        gone in.
      
        Here are the UAPI disintegration bits for the fbdev drivers.  It
        appears that Florian hasn't had time to deal with my patch, but back
        in December he did say he didn't mind if I pushed it forward."
      
      Yay.  No more uapi movement.  And hopefully no more big header file
      cleanups coming up either, it just tends to be very painful.
      
      * tag 'disintegrate-fbdev-20121220' of git://git.infradead.org/users/dhowells/linux-headers:
        UAPI: (Scripted) Disintegrate include/video
      ea882c2e
    • L
      Merge tag 'stable/for-linus-3.9-rc1-tag' of... · 8e8b180a
      Linus Torvalds 提交于
      Merge tag 'stable/for-linus-3.9-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
      
      Pull Xen bug-fixes from Konrad Rzeszutek Wilk:
       - Update the Xen ACPI memory and CPU hotplug locking mechanism.
       - Fix PAT issues wherein various applications would not start
       - Fix handling of multiple MSI as AHCI now does it.
       - Fix ARM compile failures.
      
      * tag 'stable/for-linus-3.9-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
        xenbus: fix compile failure on ARM with Xen enabled
        xen/pci: We don't do multiple MSI's.
        xen/pat: Disable PAT using pat_enabled value.
        xen/acpi: xen cpu hotplug minor updates
        xen/acpi: xen memory hotplug minor updates
      8e8b180a
    • L
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs · 56a79b7b
      Linus Torvalds 提交于
      Pull  more VFS bits from Al Viro:
       "Unfortunately, it looks like xattr series will have to wait until the
        next cycle ;-/
      
        This pile contains 9p cleanups and fixes (races in v9fs_fid_add()
        etc), fixup for nommu breakage in shmem.c, several cleanups and a bit
        more file_inode() work"
      
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
        constify path_get/path_put and fs_struct.c stuff
        fix nommu breakage in shmem.c
        cache the value of file_inode() in struct file
        9p: if v9fs_fid_lookup() gets to asking server, it'd better have hashed dentry
        9p: make sure ->lookup() adds fid to the right dentry
        9p: untangle ->lookup() a bit
        9p: double iput() in ->lookup() if d_materialise_unique() fails
        9p: v9fs_fid_add() can't fail now
        v9fs: get rid of v9fs_dentry
        9p: turn fid->dlist into hlist
        9p: don't bother with private lock in ->d_fsdata; dentry->d_lock will do just fine
        more file_inode() open-coded instances
        selinux: opened file can't have NULL or negative ->f_path.dentry
      
      (In the meantime, the hlist traversal macros have changed, so this
      required a semantic conflict fixup for the newly hlistified fid->dlist)
      56a79b7b
    • L
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs · 1c82315a
      Linus Torvalds 提交于
      Pull btrfs fixup from Chris Mason:
       "Geert and James both sent this one in, sorry guys"
      
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
        btrfs/raid56: Add missing #include <linux/vmalloc.h>
      1c82315a
    • L
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux · 530ede14
      Linus Torvalds 提交于
      Pull second set of s390 patches from Martin Schwidefsky:
       "The main part of this merge are Heikos uaccess patches.  Together with
        commit 09884964 ("mm: do not grow the stack vma just because of an
        overrun on preceding vma") the user string access is hopefully fixed
        for good.
      
        In addition some bug fixes and two cleanup patches."
      
      * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
        s390/module: fix compile warning
        qdio: remove unused parameters
        s390/uaccess: fix kernel ds access for page table walk
        s390/uaccess: fix strncpy_from_user string length check
        input: disable i8042 PC Keyboard controller for s390
        s390/dis: Fix invalid array size
        s390/uaccess: remove pointless access_ok() checks
        s390/uaccess: fix strncpy_from_user/strnlen_user zero maxlen case
        s390/uaccess: shorten strncpy_from_user/strnlen_user
        s390/dasd: fix unresponsive device after all channel paths were lost
        s390/mm: ignore change bit for vmemmap
        s390/page table dumper: add support for change-recording override bit
      530ede14
    • L
      Merge branch 'fixes-for-3.9-latest' of... · 6977c6fc
      Linus Torvalds 提交于
      Merge branch 'fixes-for-3.9-latest' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
      
      Pull second round of PARISC updates from Helge Deller:
       "The most important fix in this branch is the switch of io_setup,
        io_getevents and io_submit syscalls to use the available compat
        syscalls when running 32bit userspace on 64bit kernel.  Other than
        that it's mostly removal of compile warnings."
      
      * 'fixes-for-3.9-latest' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
        parisc: fix redefinition of SET_PERSONALITY
        parisc: do not install modules when installing kernel
        parisc: fix compile warnings triggered by atomic_sub(sizeof(),v)
        parisc: check return value of down_interruptible() in hp_sdc_rtc.c
        parisc: avoid unitialized variable warning in pa_memcpy()
        parisc: remove unused variable 'compat_val'
        parisc: switch to compat_functions of io_setup, io_getevents and io_submit
        parisc: select ARCH_WANT_FRAME_POINTERS
      6977c6fc