1. 06 Aug, 2014 1 commit
    • WANG Chao's avatar
      mm/vmalloc.c: clean up map_vm_area third argument · f6f8ed47
      WANG Chao authored
      
      
      Currently map_vm_area() takes (struct page *** pages) as third argument,
      and after mapping, it moves (*pages) to point to (*pages +
      nr_mappped_pages).
      
      It looks like this kind of increment is useless to its caller these
      days.  The callers don't care about the increments and actually they're
      trying to avoid this by passing another copy to map_vm_area().
      
      The caller can always guarantee all the pages can be mapped into vm_area
      as specified in first argument and the caller only cares about whether
      map_vm_area() fails or not.
      
      This patch cleans up the pointer movement in map_vm_area() and updates
      its callers accordingly.
      Signed-off-by: default avatarWANG Chao <chaowang@redhat.com>
      Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
      Acked-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Minchan Kim <minchan@kernel.org>
      Cc: Nitin Gupta <ngupta@vflare.org>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      f6f8ed47
  2. 22 Apr, 2013 6 commits
  3. 17 Dec, 2012 1 commit
  4. 26 Oct, 2011 2 commits
  5. 21 Jul, 2011 1 commit
  6. 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
  7. 23 Sep, 2009 1 commit
  8. 30 Jul, 2009 2 commits
    • Rusty Russell's avatar
      lguest: update commentry · a91d74a3
      Rusty Russell authored
      
      
      Every so often, after code shuffles, I need to go through and unbitrot
      the Lguest Journey (see drivers/lguest/README).  Since we now use RCU in
      a simple form in one place I took the opportunity to expand that explanation.
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
      a91d74a3
    • Rusty Russell's avatar
      lguest: fix comment style · 2e04ef76
      Rusty Russell authored
      
      
      I don't really notice it (except to begrudge the extra vertical
      space), but Ingo does.  And he pointed out that one excuse of lguest
      is as a teaching tool, it should set a good example.
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      Cc: Ingo Molnar <mingo@redhat.com>
      2e04ef76
  9. 12 Jun, 2009 5 commits
    • Rusty Russell's avatar
      lguest: remove obsolete LHREQ_BREAK call · 5dac051b
      Rusty Russell authored
      
      
      We no longer need an efficient mechanism to force the Guest back into
      host userspace, as each device is serviced without bothering the main
      Guest process (aka. the Launcher).
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      5dac051b
    • Rusty Russell's avatar
      lguest: use eventfds for device notification · df60aeef
      Rusty Russell authored
      
      
      Currently, when a Guest wants to perform I/O it calls LHCALL_NOTIFY with
      an address: the main Launcher process returns with this address, and figures
      out what device to run.
      
      A far nicer model is to let processes bind an eventfd to an address: if we
      find one, we simply signal the eventfd.
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      Cc: Davide Libenzi <davidel@xmailserver.org>
      df60aeef
    • Matias Zabaljauregui's avatar
      lguest: map switcher with executable page table entries · ed1dc778
      Matias Zabaljauregui authored
      
      
      Map switcher with executable page table entries.
      (This bug didn't matter before PAE and hence NX support -- RR)
      Signed-off-by: default avatarMatias Zabaljauregui <zabaljauregui@gmail.com>
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      ed1dc778
    • Rusty Russell's avatar
      lguest: improve interrupt handling, speed up stream networking · a32a8813
      Rusty Russell authored
      
      
      lguest never checked for pending interrupts when enabling interrupts, and
      things still worked.  However, it makes a significant difference to TCP
      performance, so it's time we fixed it by introducing a pending_irq flag
      and checking it on irq_restore and irq_enable.
      
      These two routines are now too big to patch into the 8/10 bytes
      patch space, so we drop that code.
      
      Note: The high latency on interrupt delivery had a very curious
      effect: once everything else was optimized, networking without GSO was
      faster than networking with GSO, since more interrupts were sent and
      hence a greater chance of one getting through to the Guest!
      
      Note2: (Almost) Closing the same loophole for iret doesn't have any
      measurable effect, so I'm leaving that patch for the moment.
      
      Before:
      	1GB tcpblast Guest->Host:		30.7 seconds
      	1GB tcpblast Guest->Host (no GSO):	76.0 seconds
      
      After:
      	1GB tcpblast Guest->Host:		6.8 seconds
      	1GB tcpblast Guest->Host (no GSO):	27.8 seconds
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      a32a8813
    • Rusty Russell's avatar
      lguest: fix race in halt code · abd41f03
      Rusty Russell authored
      
      
      When the Guest does the LHCALL_HALT hypercall, we go to sleep, expecting
      that a timer or the Waker will wake_up_process() us.
      
      But we do it in a stupid way, leaving a classic missing wakeup race.
      
      So split maybe_do_interrupt() into interrupt_pending() and
      try_deliver_interrupt(), and check maybe_do_interrupt() and the
      "break_out" flag before calling schedule.
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      abd41f03
  10. 30 Mar, 2009 1 commit
  11. 29 Jan, 2009 1 commit
  12. 28 Jul, 2008 1 commit
  13. 27 Mar, 2008 1 commit
  14. 10 Mar, 2008 1 commit
    • Rusty Russell's avatar
      lguest: fix __get_vm_area usage. · f14ae652
      Rusty Russell authored
      Robert Bragg's 5dc33185
      
       tightened
      (ie. fixed) the checking in __get_vm_area, and it broke lguest.
      
      lguest should pass the exact "end" it wants, not some random constant
      (it was possible previously that it would actually get an address
      different from SWITCHER_ADDR).
      
      Also, Fabio Checconi pointed out that we should make sure we're not
      hitting the fixmap area.
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      Cc: Robert Bragg <robert@sixbynine.org>
      f14ae652
  15. 30 Jan, 2008 8 commits
  16. 24 Oct, 2007 1 commit
  17. 22 Oct, 2007 6 commits