1. 24 Apr, 2010 1 commit
  2. 30 Mar, 2010 1 commit
    • Tejun Heo's avatar
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo authored
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
      
      percpu.h is included by sched.h and module.h and thus ends up being
      included when building most .c files.  percpu.h includes slab.h which
      in turn includes gfp.h making everything defined by the two files
      universally available and complicating inclusion dependencies.
      
      percpu.h -> slab.h dependency is about to be removed.  Prepare for
      this change by updating users of gfp and slab facilities include those
      headers directly instead of assuming availability.  As this conversion
      needs to touch large number of source files, the following script is
      used as the basis of conversion.
      
        http://userweb.kernel.org/~tj/misc/slabh-sweep.py
      
      
      
      The script does the followings.
      
      * Scan files for gfp and slab usages and update includes such that
        only the necessary includes are there.  ie. if only gfp is used,
        gfp.h, if slab is used, slab.h.
      
      * When the script inserts a new include, it looks at the include
        blocks and try to put the new include such that its order conforms
        to its surrounding.  It's put in the include block which contains
        core kernel includes, in the same order that the rest are ordered -
        alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
        doesn't seem to be any matching order.
      
      * If the script can't find a place to put a new include (mostly
        because the file doesn't have fitting include block), it prints out
        an error message indicating which .h file needs to be added to the
        file.
      
      The conversion was done in the following steps.
      
      1. The initial automatic conversion of all .c files updated slightly
         over 4000 files, deleting around 700 includes and adding ~480 gfp.h
         and ~3000 slab.h inclusions.  The script emitted errors for ~400
         files.
      
      2. Each error was manually checked.  Some didn't need the inclusion,
         some needed manual addition while adding it to implementation .h or
         embedding .c file was more appropriate for others.  This step added
         inclusions to around 150 files.
      
      3. The script was run again and the output was compared to the edits
         from #2 to make sure no file was left behind.
      
      4. Several build tests were done and a couple of problems were fixed.
         e.g. lib/decompress_*.c used malloc/free() wrappers around slab
         APIs requiring slab.h to be added manually.
      
      5. The script was run on all .h files but without automatically
         editing them as sprinkling gfp.h and slab.h inclusions around .h
         files could easily lead to inclusion dependency hell.  Most gfp.h
         inclusion directives were ignored as stuff from gfp.h was usually
         wildly available and often used in preprocessor macros.  Each
         slab.h inclusion directive was examined and added manually as
         necessary.
      
      6. percpu.h was updated not to include slab.h.
      
      7. Build test were done on the following configurations and failures
         were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
         distributed build env didn't work with gcov compiles) and a few
         more options had to be turned off depending on archs to make things
         build (like ipr on powerpc/64 which failed due to missing writeq).
      
         * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
         * powerpc and powerpc64 SMP allmodconfig
         * sparc and sparc64 SMP allmodconfig
         * ia64 SMP allmodconfig
         * s390 SMP allmodconfig
         * alpha SMP allmodconfig
         * um on x86_64 SMP allmodconfig
      
      8. percpu.h modifications were reverted so that it could be applied as
         a separate patch and serve as bisection point.
      
      Given the fact that I had only a couple of failures from tests on step
      6, I'm fairly confident about the coverage of this conversion patch.
      If there is a breakage, it's likely to be something in one of the arch
      headers which should be easily discoverable easily on most builds of
      the specific arch.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Guess-its-ok-by: default avatarChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  3. 24 Mar, 2010 1 commit
  4. 12 Mar, 2010 1 commit
    • Kirill A. Shutemov's avatar
      cgroup: implement eventfd-based generic API for notifications · 0dea1168
      Kirill A. Shutemov authored
      
      This patchset introduces eventfd-based API for notifications in cgroups
      and implements memory notifications on top of it.
      
      It uses statistics in memory controler to track memory usage.
      
      Output of time(1) on building kernel on tmpfs:
      
      Root cgroup before changes:
      	make -j2  506.37 user 60.93s system 193% cpu 4:52.77 total
      Non-root cgroup before changes:
      	make -j2  507.14 user 62.66s system 193% cpu 4:54.74 total
      Root cgroup after changes (0 thresholds):
      	make -j2  507.13 user 62.20s system 193% cpu 4:53.55 total
      Non-root cgroup after changes (0 thresholds):
      	make -j2  507.70 user 64.20s system 193% cpu 4:55.70 total
      Root cgroup after changes (1 thresholds, never crossed):
      	make -j2  506.97 user 62.20s system 193% cpu 4:53.90 total
      Non-root cgroup after changes (1 thresholds, never crossed):
      	make -j2  507.55 user 64.08s system 193% cpu 4:55.63 total
      
      This patch:
      
      Introduce the write-only file "cgroup.event_control" in every cgroup.
      
      To register new notification handler you need:
      - create an eventfd;
      - open a control file to be monitored. Callbacks register_event() and
        unregister_event() must be defined for the control file;
      - write "<event_fd> <control_fd> <args>" to cgroup.event_control.
        Interpretation of args is defined by control file implementation;
      
      eventfd will be woken up by control file implementation or when the
      cgroup is removed.
      
      To unregister notification handler just close eventfd.
      
      If you need notification functionality for a control file you have to
      implement callbacks register_event() and unregister_event() in the
      struct cftype.
      
      [kamezawa.hiroyu@jp.fujitsu.com: Kconfig fix]
      Signed-off-by: default avatarKirill A. Shutemov <kirill@shutemov.name>
      Reviewed-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Paul Menage <menage@google.com>
      Cc: Li Zefan <lizf@cn.fujitsu.com>
      Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
      Cc: Pavel Emelyanov <xemul@openvz.org>
      Cc: Dan Malek <dan@embeddedalley.com>
      Cc: Vladislav Buzov <vbuzov@embeddedalley.com>
      Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
      Cc: Alexander Shishkin <virtuoso@slind.org>
      Cc: Davide Libenzi <davidel@xmailserver.org>
      Signed-off-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      0dea1168
  5. 06 Mar, 2010 4 commits
  6. 03 Mar, 2010 1 commit
    • Eric W. Biederman's avatar
      init: Open /dev/console from rootfs · 2bd3a997
      Eric W. Biederman authored
      
      To avoid potential problems with an empty /dev open /dev/console
      from rootfs instead of waiting to mount our root filesystem and
      mounting it there.   This effectively guarantees that there will
      be a device node, and it won't be on a filesystem that we will
      ever unmount, so there are no issues with leaving /dev/console
      open and pinning the filesystem.
      
      This is actually more effective than automatically mounting
      devtmpfs on /dev because it removes removes the occasionally
      problematic assumption that /dev/console exists from the boot
      code.
      
      With this patch I was able to throw busybox on my /boot partition
      (which has no /dev directory) and boot into userspace without
      problems.
      
      The only possible negative consequence I can think of is that
      someone out there deliberately used did not use a character device
      that is major 5 minor 2 for /dev/console.  Does anyone know of a
      situation in which that could make sense?
      Signed-off-by: default avatarEric W. Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      2bd3a997
  7. 26 Feb, 2010 1 commit
  8. 25 Feb, 2010 2 commits
    • Paul E. McKenney's avatar
      rcu: Accelerate grace period if last non-dynticked CPU · 8bd93a2c
      Paul E. McKenney authored
      
      Currently, rcu_needs_cpu() simply checks whether the current CPU
      has an outstanding RCU callback, which means that the last CPU
      to go into dyntick-idle mode might wait a few ticks for the
      relevant grace periods to complete.  However, if all the other
      CPUs are in dyntick-idle mode, and if this CPU is in a quiescent
      state (which it is for RCU-bh and RCU-sched any time that we are
      considering going into dyntick-idle mode), then the grace period
      is instantly complete.
      
      This patch therefore repeatedly invokes the RCU grace-period
      machinery in order to force any needed grace periods to complete
      quickly.  It does so a limited number of times in order to
      prevent starvation by an RCU callback function that might pass
      itself to call_rcu().
      
      However, if any CPU other than the current one is not in
      dyntick-idle mode, fall back to simply checking (with fix to bug
      noted by Lai Jiangshan).  Also, take advantage of last
      grace-period forcing, the opportunity to do so noted by Steve
      Rostedt.  And apply simplified #ifdef condition suggested by
      Frederic Weisbecker.
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-15-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      8bd93a2c
    • Paul E. McKenney's avatar
      sched: Use lockdep-based checking on rcu_dereference() · d11c563d
      Paul E. McKenney authored
      
      Update the rcu_dereference() usages to take advantage of the new
      lockdep-based checking.
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <1266887105-1528-6-git-send-email-paulmck@linux.vnet.ibm.com>
      [ -v2: fix allmodconfig missing symbol export build failure on x86 ]
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      d11c563d
  9. 17 Feb, 2010 2 commits
  10. 07 Feb, 2010 1 commit
  11. 21 Jan, 2010 1 commit
  12. 11 Jan, 2010 1 commit
    • Albin Tonnerre's avatar
      lib: add support for LZO-compressed kernels · 7dd65feb
      Albin Tonnerre authored
      
      This patch series adds generic support for creating and extracting
      LZO-compressed kernel images, as well as support for using such images on
      the x86 and ARM architectures, and support for creating and using
      LZO-compressed initrd and initramfs images.
      
      Russell King said:
      
      : Testing on a Cortex A9 model:
      : - lzo decompressor is 65% of the time gzip takes to decompress a kernel
      : - lzo kernel is 9% larger than a gzip kernel
      :
      : which I'm happy to say confirms your figures when comparing the two.
      :
      : However, when comparing your new gzip code to the old gzip code:
      : - new is 99% of the size of the old code
      : - new takes 42% of the time to decompress than the old code
      :
      : What this means is that for a proper comparison, the results get even better:
      : - lzo is 7.5% larger than the old gzip'd kernel image
      : - lzo takes 28% of the time that the old gzip code took
      :
      : So the expense seems definitely worth the effort.  The only reason I
      : can think of ever using gzip would be if you needed the additional
      : compression (eg, because you have limited flash to store the image.)
      :
      : I would argue that the default for ARM should therefore be LZO.
      
      This patch:
      
      The lzo compressor is worse than gzip at compression, but faster at
      extraction.  Here are some figures for an ARM board I'm working on:
      
      Uncompressed size: 3.24Mo
      gzip  1.61Mo 0.72s
      lzo   1.75Mo 0.48s
      
      So for a compression ratio that is still relatively close to gzip, it's
      much faster to extract, at least in that case.
      
      This part contains:
       - Makefile routine to support lzo compression
       - Fixes to the existing lzo compressor so that it can be used in
         compressed kernels
       - wrapper around the existing lzo1x_decompress, as it only extracts one
         block at a time, while we need to extract a whole file here
       - config dialog for kernel compression
      
      [akpm@linux-foundation.org: coding-style fixes]
      [akpm@linux-foundation.org: cleanup]
      Signed-off-by: default avatarAlbin Tonnerre <albin.tonnerre@free-electrons.com>
      Tested-by: default avatarWu Zhangjin <wuzhangjin@gmail.com>
      Acked-by: default avatar"H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Tested-by: default avatarRussell King <rmk@arm.linux.org.uk>
      Acked-by: default avatarRussell King <rmk@arm.linux.org.uk>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      7dd65feb
  13. 06 Jan, 2010 1 commit
  14. 28 Dec, 2009 1 commit
    • Li Zefan's avatar
      perf events: Remove CONFIG_EVENT_PROFILE · 07b139c8
      Li Zefan authored
      
      Quoted from Ingo:
      
      | This reminds me - i think we should eliminate CONFIG_EVENT_PROFILE -
      | it's an unnecessary Kconfig complication. If both PERF_EVENTS and
      | EVENT_TRACING is enabled we should expose generic tracepoints.
      |
      | Nor is it limited to event 'profiling', so it has become a misnomer as
      | well.
      Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Paul Mackerras <paulus@samba.org>
      LKML-Reference: <4B2F1557.2050705@cn.fujitsu.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      07b139c8
  15. 16 Dec, 2009 1 commit
  16. 15 Dec, 2009 3 commits
  17. 12 Dec, 2009 2 commits
  18. 08 Dec, 2009 1 commit
  19. 02 Dec, 2009 1 commit
  20. 01 Dec, 2009 2 commits
  21. 26 Nov, 2009 1 commit
    • Mike Travis's avatar
      timers, init: Limit the number of per cpu calibration bootup messages · feae3203
      Mike Travis authored
      
      Limit the number of per cpu calibration messages by only
      printing out results for the first cpu to boot.
      
      Also, don't print "CPUx is down" as this is expected, and we
      don't need 4096 reminders... ;-)
      Signed-off-by: default avatarMike Travis <travis@sgi.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Roland Dreier <rdreier@cisco.com>
      Cc: Randy Dunlap <rdunlap@xenotime.net>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Greg Kroah-Hartman <gregkh@suse.de>
      Cc: Yinghai Lu <yhlu.kernel@gmail.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
      Cc: Jack Steiner <steiner@sgi.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      LKML-Reference: <20091118002219.889552000@alcatraz.americas.sgi.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      feae3203
  22. 19 Nov, 2009 1 commit
    • David Howells's avatar
      SLOW_WORK: Allow the work items to be viewed through a /proc file · 8fba10a4
      David Howells authored
      
      Allow the executing and queued work items to be viewed through a /proc file
      for debugging purposes.  The contents look something like the following:
      
          THR PID   ITEM ADDR        FL MARK  DESC
          === ===== ================ == ===== ==========
            0  3005 ffff880023f52348  a 952ms FSC: OBJ17d3: LOOK
            1  3006 ffff880024e33668  2 160ms FSC: OBJ17e5 OP60d3b: Write1/Store fl=2
            2  3165 ffff8800296dd180  a 424ms FSC: OBJ17e4: LOOK
            3  4089 ffff8800262c8d78  a 212ms FSC: OBJ17ea: CRTN
            4  4090 ffff88002792bed8  2 388ms FSC: OBJ17e8 OP60d36: Write1/Store fl=2
            5  4092 ffff88002a0ef308  2 388ms FSC: OBJ17e7 OP60d2e: Write1/Store fl=2
            6  4094 ffff88002abaf4b8  2 132ms FSC: OBJ17e2 OP60d4e: Write1/Store fl=2
            7  4095 ffff88002bb188e0  a 388ms FSC: OBJ17e9: CRTN
          vsq     - ffff880023d99668  1 308ms FSC: OBJ17e0 OP60f91: Write1/EnQ fl=2
          vsq     - ffff8800295d1740  1 212ms FSC: OBJ16be OP4d4b6: Write1/EnQ fl=2
          vsq     - ffff880025ba3308  1 160ms FSC: OBJ179a OP58dec: Write1/EnQ fl=2
          vsq     - ffff880024ec83e0  1 160ms FSC: OBJ17ae OP599f2: Write1/EnQ fl=2
          vsq     - ffff880026618e00  1 160ms FSC: OBJ17e6 OP60d33: Write1/EnQ fl=2
          vsq     - ffff880025a2a4b8  1 132ms FSC: OBJ16a2 OP4d583: Write1/EnQ fl=2
          vsq     - ffff880023cbe6d8  9 212ms FSC: OBJ17eb: LOOK
          vsq     - ffff880024d37590  9 212ms FSC: OBJ17ec: LOOK
          vsq     - ffff880027746cb0  9 212ms FSC: OBJ17ed: LOOK
          vsq     - ffff880024d37ae8  9 212ms FSC: OBJ17ee: LOOK
          vsq     - ffff880024d37cb0  9 212ms FSC: OBJ17ef: LOOK
          vsq     - ffff880025036550  9 212ms FSC: OBJ17f0: LOOK
          vsq     - ffff8800250368e0  9 212ms FSC: OBJ17f1: LOOK
          vsq     - ffff880025036aa8  9 212ms FSC: OBJ17f2: LOOK
      
      In the 'THR' column, executing items show the thread they're occupying and
      queued threads indicate which queue they're on.  'PID' shows the process ID of
      a slow-work thread that's executing something.  'FL' shows the work item flags.
      'MARK' indicates how long since an item was queued or began executing.  Lastly,
      the 'DESC' column permits the owner of an item to give some information.
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      8fba10a4
  23. 13 Nov, 2009 1 commit
    • Thomas Gleixner's avatar
      locking: Make inlining decision Kconfig based · 6beb0009
      Thomas Gleixner authored
      commit 892a7c67
      
       (locking: Allow arch-inlined spinlocks) implements the
      selection of which lock functions are inlined based on defines in
      arch/.../spinlock.h: #define __always_inline__LOCK_FUNCTION
      
      Despite of the name __always_inline__* the lock functions can be built
      out of line depending on config options. Also if the arch does not set
      some inline defines the generic code might set them; again depending on
      config options.
      
      This makes it unnecessary hard to figure out when and which lock
      functions are inlined. Aside of that it makes it way harder and
      messier for -rt to manipulate the lock functions.
      
      Convert the inlining decision to CONFIG switches. Each lock function
      is inlined depending on CONFIG_INLINE_*. The configs implement the
      existing dependencies. The architecture code can select ARCH_INLINE_*
      to signal that it wants the corresponding lock function inlined.
      ARCH_INLINE_* is necessary as Kconfig ignores "depends on"
      restrictions when a config element is selected.
      
      No functional change.
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      LKML-Reference: <20091109151428.504477141@linutronix.de>
      Acked-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
      Reviewed-by: default avatarIngo Molnar <mingo@elte.hu>
      Acked-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
      6beb0009
  24. 11 Nov, 2009 1 commit
    • Eric W. Biederman's avatar
      sysctl: Reduce sys_sysctl to a compatibility wrapper around /proc/sys · 26a7034b
      Eric W. Biederman authored
      
      To simply maintenance and to be able to remove all of the binary
      sysctl support from various subsystems I have rewritten the binary
      sysctl code as a compatibility wrapper around proc/sys.
      
      The code is built around a hard coded table based on the table
      in sysctl_check.c that lists all of our current binary sysctls
      and provides enough information to convert from the sysctl
      binary input into into ascii and back again.  New in this
      patch is the realization that the only dynamic entries
      that need to be handled have ifname as the asscii string
      and ifindex as their ctl_name.
      
      When a sys_sysctl is called the code now looks in the
      translation table converting the binary name to the
      path under /proc where the value is to be found.  Opens
      that file, and calls into a format conversion wrapper
      that calls fop->read and then fop->write as appropriate.
      
      Since in practice the practically no one uses or tests
      sys_sysctl rewritting the code to be beautiful is a little
      silly.  The redeeming merit of this work is it allows us to
      rip out all of the binary sysctl syscall support from
      everywhere else in the tree.  Allowing us to remove
      a lot of dead (after this patch) and barely maintained code.
      
      In addition it becomes much easier to optimize the sysctl
      implementation for being the backing store of /proc/sys,
      without having to worry about sys_sysctl.
      Signed-off-by: default avatarEric W. Biederman <ebiederm@xmission.com>
      26a7034b
  25. 02 Nov, 2009 1 commit
  26. 27 Oct, 2009 1 commit
  27. 26 Oct, 2009 1 commit
    • Paul E. McKenney's avatar
      rcu: "Tiny RCU", The Bloatwatch Edition · 9b1d82fa
      Paul E. McKenney authored
      This patch is a version of RCU designed for !SMP provided for a
      small-footprint RCU implementation.  In particular, the
      implementation of synchronize_rcu() is extremely lightweight and
      high performance. It passes rcutorture testing in each of the
      four relevant configurations (combinations of NO_HZ and PREEMPT)
      on x86.  This saves about 1K bytes compared to old Classic RCU
      (which is no longer in mainline), and more than three kilobytes
      compared to Hierarchical RCU (updated to 2.6.30):
      
      	CONFIG_TREE_RCU:
      
      	   text	   data	    bss	    dec	    filename
      	    183       4       0     187     kernel/rcupdate.o
      	   2783     520      36    3339     kernel/rcutree.o
      				   3526 Total (vs 4565 for v7)
      
      	CONFIG_TREE_PREEMPT_RCU:
      
      	   text	   data	    bss	    dec	    filename
      	    263       4       0     267     kernel/rcupdate.o
      	   4594     776      52    5422     kernel/rcutree.o
      	   			   5689 Total (6155 for v7)
      
      	CONFIG_TINY_RCU:
      
      	   text	   data	    bss	    dec	    filename
      	     96       4       0     100     kernel/rcupdate.o
      	    734      24       0     758     kernel/rcutiny.o
      	    			    858 Total (vs 848 for v7)
      
      The above is for x86.  Your mileage may vary on other platforms.
      Further compression is possible, but is being procrastinated.
      
      Changes from v7 (http://lkml.org/lkml/2009/10/9/388)
      
      o	Apply Lai Jiangshan's review comments (aside from
      might_sleep() 	in synchronize_sched(), which is covered by SMP builds).
      
      o	Fix up expedited primitives.
      
      Changes from v6 (http://lkml.org/lkml/2009/9/23/293).
      
      o	Forward ported to put it into the 2.6.33 stream.
      
      o	Added lockdep support.
      
      o	Make lightweight rcu_barrier.
      
      Changes from v5 (http://lkml.org/lkml/2009/6/23/12).
      
      o	Ported to latest pre-2.6.32 merge window kernel.
      
      	- Renamed rcu_qsctr_inc() to rcu_sched_qs().
      	- Renamed rcu_bh_qsctr_inc() to rcu_bh_qs().
      	- Provided trivial rcu_cpu_notify().
      	- Provided trivial exit_rcu().
      	- Provided trivial rcu_needs_cpu().
      	- Fixed up the rcu_*_enter/exit() functions in linux/hardirq.h.
      
      o	Removed the dependence on EMBEDDED, with a view to making
      	TINY_RCU default for !SMP at some time in the future.
      
      o	Added (trivial) support for expedited grace periods.
      
      Changes from v4 (http://lkml.org/lkml/2009/5/2/91) include:
      
      o	Squeeze the size down a bit further by removing the
      	->completed field from struct rcu_ctrlblk.
      
      o	This permits synchronize_rcu() to become the empty function.
      	Previous concerns about rcutorture were unfounded, as
      	rcutorture correctly handles a constant value from
      	rcu_batches_completed() and rcu_batches_completed_bh().
      
      Changes from v3 (http://lkml.org/lkml/2009/3/29/221) include:
      
      o	Changed rcu_batches_completed(), rcu_batches_completed_bh()
      	rcu_enter_nohz(), rcu_exit_nohz(), rcu_nmi_enter(), and
      	rcu_nmi_exit(), to be static inlines, as suggested by David
      	Howells.  Doing this saves about 100 bytes from rcutiny.o.
      	(The numbers between v3 and this v4 of the patch are not directly
      	comparable, since they are against different versions of Linux.)
      
      Changes from v2 (http://lkml.org/lkml/2009/2/3/333) include:
      
      o	Fix whitespace issues.
      
      o	Change short-circuit "||" operator to instead be "+" in order
      to 	fix performance bug noted by "kraai" on LWN.
      
      		(http://lwn.net/Articles/324348/)
      
      Changes from v1 (http://lkml.org/lkml/2009/1/13/440
      
      ) include:
      
      o	This version depends on EMBEDDED as well as !SMP, as suggested
      	by Ingo.
      
      o	Updated rcu_needs_cpu() to unconditionally return zero,
      	permitting the CPU to enter dynticks-idle mode at any time.
      	This works because callbacks can be invoked upon entry to
      	dynticks-idle mode.
      
      o	Paul is now OK with this being included, based on a poll at
      the 	Kernel Miniconf at linux.conf.au, where about ten people said
      	that they cared about saving 900 bytes on single-CPU systems.
      
      o	Applies to both mainline and tip/core/rcu.
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Acked-by: default avatarDavid Howells <dhowells@redhat.com>
      Acked-by: default avatarJosh Triplett <josh@joshtriplett.org>
      Reviewed-by: default avatarLai Jiangshan <laijs@cn.fujitsu.com>
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: avi@redhat.com
      Cc: mtosatti@redhat.com
      LKML-Reference: <12565226351355-git-send-email->
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      9b1d82fa
  28. 06 Oct, 2009 1 commit
    • Peter Zijlstra's avatar
      perf_event: Provide vmalloc() based mmap() backing · 906010b2
      Peter Zijlstra authored
      
      Some architectures such as Sparc, ARM and MIPS (basically
      everything with flush_dcache_page()) need to deal with dcache
      aliases by carefully placing pages in both kernel and user maps.
      
      These architectures typically have to use vmalloc_user() for this.
      
      However, on other architectures, vmalloc() is not needed and has
      the downsides of being more restricted and slower than regular
      allocations.
      Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: default avatarDavid Miller <davem@davemloft.net>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Jens Axboe <jens.axboe@oracle.com>
      Cc: Paul Mackerras <paulus@samba.org>
      LKML-Reference: <1254830228.21044.272.camel@laptop>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      906010b2
  29. 23 Sep, 2009 3 commits
    • Alexey Dobriyan's avatar
      headers: utsname.h redux · 2bcd57ab
      Alexey Dobriyan authored
      
      * remove asm/atomic.h inclusion from linux/utsname.h --
         not needed after kref conversion
       * remove linux/utsname.h inclusion from files which do not need it
      
      NOTE: it looks like fs/binfmt_elf.c do not need utsname.h, however
      due to some personality stuff it _is_ needed -- cowardly leave ELF-related
      headers and files alone.
      Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      2bcd57ab
    • Rusty Russell's avatar
      cpumask: remove unused cpu_mask_all · 72d78d05
      Rusty Russell authored
      
      It's only defined for NR_CPUS > BITS_PER_LONG; cpu_all_mask is always
      defined (and const).
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      72d78d05
    • Paul E. McKenney's avatar
      rcu: Clean up code based on review feedback from Josh Triplett, part 2 · 1eba8f84
      Paul E. McKenney authored
      
      These issues identified during an old-fashioned face-to-face code
      review extending over many hours.
      
      o	Add comments for tricky parts of code, and correct comments
      	that have passed their sell-by date.
      
      o	Get rid of the vestiges of rcu_init_sched(), which is no
      	longer needed now that PREEMPT_RCU is gone.
      
      o	Move the #include of rcutree_plugin.h to the end of
      	rcutree.c, which means that, rather than having a random
      	collection of forward declarations, the new set of forward
      	declarations document the set of plugins.  The new home for
      	this #include also allows __rcu_init_preempt() to move into
      	rcutree_plugin.h.
      
      o	Fix rcu_preempt_check_callbacks() to be static.
      Suggested-by: default avatarJosh Triplett <josh@joshtriplett.org>
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: akpm@linux-foundation.org
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <12537246443924-git-send-email->
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      Peter Zijlstra <peterz@infradead.org>
      1eba8f84