1. 15 10月, 2012 2 次提交
  2. 13 10月, 2012 1 次提交
    • J
      vfs: define struct filename and have getname() return it · 91a27b2a
      Jeff Layton 提交于
      getname() is intended to copy pathname strings from userspace into a
      kernel buffer. The result is just a string in kernel space. It would
      however be quite helpful to be able to attach some ancillary info to
      the string.
      
      For instance, we could attach some audit-related info to reduce the
      amount of audit-related processing needed. When auditing is enabled,
      we could also call getname() on the string more than once and not
      need to recopy it from userspace.
      
      This patchset converts the getname()/putname() interfaces to return
      a struct instead of a string. For now, the struct just tracks the
      string in kernel space and the original userland pointer for it.
      
      Later, we'll add other information to the struct as it becomes
      convenient.
      Signed-off-by: NJeff Layton <jlayton@redhat.com>
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      91a27b2a
  3. 30 5月, 2012 1 次提交
  4. 21 5月, 2012 1 次提交
  5. 21 3月, 2012 1 次提交
  6. 01 3月, 2012 1 次提交
  7. 12 12月, 2011 3 次提交
    • F
      nohz: Remove tick_nohz_idle_enter_norcu() / tick_nohz_idle_exit_norcu() · 1268fbc7
      Frederic Weisbecker 提交于
      Those two APIs were provided to optimize the calls of
      tick_nohz_idle_enter() and rcu_idle_enter() into a single
      irq disabled section. This way no interrupt happening in-between would
      needlessly process any RCU job.
      
      Now we are talking about an optimization for which benefits
      have yet to be measured. Let's start simple and completely decouple
      idle rcu and dyntick idle logics to simplify.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      1268fbc7
    • F
      nohz: Allow rcu extended quiescent state handling seperately from tick stop · 2bbb6817
      Frederic Weisbecker 提交于
      It is assumed that rcu won't be used once we switch to tickless
      mode and until we restart the tick. However this is not always
      true, as in x86-64 where we dereference the idle notifiers after
      the tick is stopped.
      
      To prepare for fixing this, add two new APIs:
      tick_nohz_idle_enter_norcu() and tick_nohz_idle_exit_norcu().
      
      If no use of RCU is made in the idle loop between
      tick_nohz_enter_idle() and tick_nohz_exit_idle() calls, the arch
      must instead call the new *_norcu() version such that the arch doesn't
      need to call rcu_idle_enter() and rcu_idle_exit().
      
      Otherwise the arch must call tick_nohz_enter_idle() and
      tick_nohz_exit_idle() and also call explicitly:
      
      - rcu_idle_enter() after its last use of RCU before the CPU is put
      to sleep.
      - rcu_idle_exit() before the first use of RCU after the CPU is woken
      up.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Mike Frysinger <vapier@gentoo.org>
      Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
      Cc: David Miller <davem@davemloft.net>
      Cc: Chris Metcalf <cmetcalf@tilera.com>
      Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Russell King <linux@arm.linux.org.uk>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      2bbb6817
    • F
      nohz: Separate out irq exit and idle loop dyntick logic · 280f0677
      Frederic Weisbecker 提交于
      The tick_nohz_stop_sched_tick() function, which tries to delay
      the next timer tick as long as possible, can be called from two
      places:
      
      - From the idle loop to start the dytick idle mode
      - From interrupt exit if we have interrupted the dyntick
      idle mode, so that we reprogram the next tick event in
      case the irq changed some internal state that requires this
      action.
      
      There are only few minor differences between both that
      are handled by that function, driven by the ts->inidle
      cpu variable and the inidle parameter. The whole guarantees
      that we only update the dyntick mode on irq exit if we actually
      interrupted the dyntick idle mode, and that we enter in RCU extended
      quiescent state from idle loop entry only.
      
      Split this function into:
      
      - tick_nohz_idle_enter(), which sets ts->inidle to 1, enters
      dynticks idle mode unconditionally if it can, and enters into RCU
      extended quiescent state.
      
      - tick_nohz_irq_exit() which only updates the dynticks idle mode
      when ts->inidle is set (ie: if tick_nohz_idle_enter() has been called).
      
      To maintain symmetry, tick_nohz_restart_sched_tick() has been renamed
      into tick_nohz_idle_exit().
      
      This simplifies the code and micro-optimize the irq exit path (no need
      for local_irq_save there). This also prepares for the split between
      dynticks and rcu extended quiescent state logics. We'll need this split to
      further fix illegal uses of RCU in extended quiescent states in the idle
      loop.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Mike Frysinger <vapier@gentoo.org>
      Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
      Cc: David Miller <davem@davemloft.net>
      Cc: Chris Metcalf <cmetcalf@tilera.com>
      Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Russell King <linux@arm.linux.org.uk>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Paul Mundt <lethal@linux-sh.org>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
      280f0677
  8. 23 7月, 2011 1 次提交
  9. 25 5月, 2011 1 次提交
  10. 18 11月, 2010 1 次提交
  11. 22 10月, 2010 1 次提交
  12. 07 10月, 2010 1 次提交
    • D
      Blackfin: Rename IRQ flags handling functions · 3b139cdb
      David Howells 提交于
      Rename h/w IRQ flags handling functions to be in line with what is expected for
      the irq renaming patch.  This renames local_*_hw() to hard_local_*() using the
      following perl command:
      
      	perl -pi -e 's/local_irq_(restore|enable|disable)_hw/hard_local_irq_\1/ or s/local_irq_save_hw([_a-z]*)[(]flags[)]/flags = hard_local_irq_save\1()/' `find arch/blackfin/ -name "*.[ch]"`
      
      and then fixing up asm/irqflags.h manually.
      
      Additionally, arch/hard_local_save_flags() and arch/hard_local_irq_save() both
      return the flags rather than passing it through the argument list.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      3b139cdb
  13. 18 8月, 2010 1 次提交
    • D
      Make do_execve() take a const filename pointer · d7627467
      David Howells 提交于
      Make do_execve() take a const filename pointer so that kernel_execve() compiles
      correctly on ARM:
      
      arch/arm/kernel/sys_arm.c:88: warning: passing argument 1 of 'do_execve' discards qualifiers from pointer target type
      
      This also requires the argv and envp arguments to be consted twice, once for
      the pointer array and once for the strings the array points to.  This is
      because do_execve() passes a pointer to the filename (now const) to
      copy_strings_kernel().  A simpler alternative would be to cast the filename
      pointer in do_execve() when it's passed to copy_strings_kernel().
      
      do_execve() may not change any of the strings it is passed as part of the argv
      or envp lists as they are some of them in .rodata, so marking these strings as
      const should be fine.
      
      Further kernel_execve() and sys_execve() need to be changed to match.
      
      This has been test built on x86_64, frv, arm and mips.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Tested-by: NRalf Baechle <ralf@linux-mips.org>
      Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d7627467
  14. 14 8月, 2010 1 次提交
  15. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo 提交于
      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: NTejun Heo <tj@kernel.org>
      Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  16. 09 3月, 2010 1 次提交
  17. 15 12月, 2009 2 次提交
  18. 25 11月, 2009 1 次提交
  19. 14 10月, 2009 1 次提交
  20. 07 10月, 2009 1 次提交
    • R
      Blackfin: mass clean up of copyright/licensing info · 96f1050d
      Robin Getz 提交于
      Bill Gatliff & David Brownell pointed out we were missing some
      copyrights, and licensing terms in some of the files in
      ./arch/blackfin, so this fixes things, and cleans them up.
      
      It also removes:
       - verbose GPL text(refer to the top level ./COPYING file)
       - file names (you are looking at the file)
       - bug url (it's in the ./MAINTAINERS file)
       - "or later" on GPL-2, when we did not have that right
      
      It also allows some Blackfin-specific assembly files to be under a BSD
      like license (for people to use them outside of Linux).
      Signed-off-by: NRobin Getz <robin.getz@analog.com>
      Signed-off-by: NMike Frysinger <vapier@gentoo.org>
      96f1050d
  21. 17 9月, 2009 1 次提交
  22. 16 7月, 2009 1 次提交
  23. 23 6月, 2009 1 次提交
  24. 19 6月, 2009 1 次提交
  25. 12 6月, 2009 1 次提交
  26. 03 4月, 2009 1 次提交
  27. 24 3月, 2009 1 次提交
  28. 07 1月, 2009 2 次提交
  29. 18 11月, 2008 1 次提交
  30. 28 10月, 2008 2 次提交
  31. 19 7月, 2008 1 次提交
    • T
      nohz: prevent tick stop outside of the idle loop · b8f8c3cf
      Thomas Gleixner 提交于
      Jack Ren and Eric Miao tracked down the following long standing
      problem in the NOHZ code:
      
      	scheduler switch to idle task
      	enable interrupts
      
      Window starts here
      
      	----> interrupt happens (does not set NEED_RESCHED)
      	      	irq_exit() stops the tick
      
      	----> interrupt happens (does set NEED_RESCHED)
      
      	return from schedule()
      	
      	cpu_idle(): preempt_disable();
      
      Window ends here
      
      The interrupts can happen at any point inside the race window. The
      first interrupt stops the tick, the second one causes the scheduler to
      rerun and switch away from idle again and we end up with the tick
      disabled.
      
      The fact that it needs two interrupts where the first one does not set
      NEED_RESCHED and the second one does made the bug obscure and extremly
      hard to reproduce and analyse. Kudos to Jack and Eric.
      
      Solution: Limit the NOHZ functionality to the idle loop to make sure
      that we can not run into such a situation ever again.
      
      cpu_idle()
      {
      	preempt_disable();
      
      	while(1) {
      		 tick_nohz_stop_sched_tick(1); <- tell NOHZ code that we
      		 			          are in the idle loop
      
      		 while (!need_resched())
      		       halt();
      
      		 tick_nohz_restart_sched_tick(); <- disables NOHZ mode
      		 preempt_enable_no_resched();
      		 schedule();
      		 preempt_disable();
      	}
      }
      
      In hindsight we should have done this forever, but ... 
      
      /me grabs a large brown paperbag.
      
      Debugged-by: Jack Ren <jack.ren@marvell.com>, 
      Debugged-by: Neric miao <eric.y.miao@gmail.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      b8f8c3cf
  32. 07 5月, 2008 1 次提交
  33. 24 4月, 2008 1 次提交
    • B
      [Blackfin] arch: This allows XIP to work with FD-PIC. · d5adb029
      Bernd Schmidt 提交于
      Previously, init failed to do anything meaningful;
      it turns out that the reason is that FD-PIC has a readonly data
      section which can be located in the XIP filesystem, and various address checks
      in the kernel reject such addresses for syscall arguments.  Hence, init's
        execve ("/bin/sh", ...)
      failed with error code EFAULT.
      
      There's room for improvement here: in case people want to have filesystems
      on flash rather than in main memory, _access_ok should be modified to
      allow this.
      
      This bug fix is also dedicated to Michael Hennerich.
      Signed-off-by: NBernd Schmidt <bernds_cb1@t-online.de>
      Signed-off-by: NBryan Wu <cooloney@kernel.org>
      d5adb029
  34. 07 3月, 2008 1 次提交