1. 20 10月, 2016 1 次提交
  2. 18 1月, 2015 1 次提交
    • J
      netlink: make nlmsg_end() and genlmsg_end() void · 053c095a
      Johannes Berg 提交于
      Contrary to common expectations for an "int" return, these functions
      return only a positive value -- if used correctly they cannot even
      return 0 because the message header will necessarily be in the skb.
      
      This makes the very common pattern of
      
        if (genlmsg_end(...) < 0) { ... }
      
      be a whole bunch of dead code. Many places also simply do
      
        return nlmsg_end(...);
      
      and the caller is expected to deal with it.
      
      This also commonly (at least for me) causes errors, because it is very
      common to write
      
        if (my_function(...))
          /* error condition */
      
      and if my_function() does "return nlmsg_end()" this is of course wrong.
      
      Additionally, there's not a single place in the kernel that actually
      needs the message length returned, and if anyone needs it later then
      it'll be very easy to just use skb->len there.
      
      Remove this, and make the functions void. This removes a bunch of dead
      code as described above. The patch adds lines because I did
      
      -	return nlmsg_end(...);
      +	nlmsg_end(...);
      +	return 0;
      
      I could have preserved all the function's return values by returning
      skb->len, but instead I've audited all the places calling the affected
      functions and found that none cared. A few places actually compared
      the return value with <= 0 in dump functionality, but that could just
      be changed to < 0 with no change in behaviour, so I opted for the more
      efficient version.
      
      One instance of the error I've made numerous times now is also present
      in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
      check for <0 or <=0 and thus broke out of the loop every single time.
      I've preserved this since it will (I think) have caused the messages to
      userspace to be formatted differently with just a single message for
      every SKB returned to userspace. It's possible that this isn't needed
      for the tools that actually use this, but I don't even know what they
      are so couldn't test that changing this behaviour would be acceptable.
      Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      053c095a
  3. 20 11月, 2013 1 次提交
  4. 11 9月, 2012 1 次提交
  5. 06 8月, 2010 1 次提交
  6. 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
  7. 01 12月, 2009 1 次提交
    • D
      dlm: always use GFP_NOFS · 573c24c4
      David Teigland 提交于
      Replace all GFP_KERNEL and ls_allocation with GFP_NOFS.
      ls_allocation would be GFP_KERNEL for userland lockspaces
      and GFP_NOFS for file system lockspaces.
      
      It was discovered that any lockspaces on the system can
      affect all others by triggering memory reclaim in the
      file system which could in turn call back into the dlm
      to acquire locks, deadlocking dlm threads that were
      shared by all lockspaces, like dlm_recv.
      Signed-off-by: NDavid Teigland <teigland@redhat.com>
      573c24c4
  8. 13 7月, 2009 1 次提交
    • J
      genetlink: make netns aware · 134e6375
      Johannes Berg 提交于
      This makes generic netlink network namespace aware. No
      generic netlink families except for the controller family
      are made namespace aware, they need to be checked one by
      one and then set the family->netnsok member to true.
      
      A new function genlmsg_multicast_netns() is introduced to
      allow sending a multicast message in a given namespace,
      for example when it applies to an object that lives in
      that namespace, a new function genlmsg_multicast_allns()
      to send a message to all network namespaces (for objects
      that do not have an associated netns).
      
      The function genlmsg_multicast() is changed to multicast
      the message in just init_net, which is currently correct
      for all generic netlink families since they only work in
      init_net right now. Some will later want to work in all
      net namespaces because they do not care about the netns
      at all -- those will have to be converted to use one of
      the new functions genlmsg_multicast_allns() or
      genlmsg_multicast_netns() whenever they are made netns
      aware in some way.
      
      After this patch families can easily decide whether or
      not they should be available in all net namespaces. Many
      genl families us it for objects not related to networking
      and should therefore be available in all namespaces, but
      that will have to be done on a per family basis.
      
      Note that this doesn't touch on the checkpoint/restart
      problem where network namespaces could be used, genl
      families and multicast groups are numbered globally and
      I see no easy way of changing that, especially since it
      must be possible to multicast to all network namespaces
      for those families that do not care about netns.
      Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      134e6375
  9. 24 12月, 2008 1 次提交
    • D
      dlm: change lock time stamping · eeda418d
      David Teigland 提交于
      Use ktime instead of jiffies for timestamping lkb's.  Also stamp the
      time on every lkb whenever it's added to a resource queue, instead of
      just stamping locks subject to timeouts.  This will allow us to use
      timestamps more widely for debugging all locks.
      Signed-off-by: NDavid Teigland <teigland@redhat.com>
      eeda418d
  10. 26 11月, 2008 1 次提交
  11. 20 5月, 2008 1 次提交
  12. 07 2月, 2008 2 次提交
  13. 09 7月, 2007 2 次提交
    • D
      [DLM] timeout fixes · 84d8cd69
      David Teigland 提交于
      Various fixes related to the new timeout feature:
      - add_timeout() missed setting TIMEWARN flag on lkb's when the
        TIMEOUT flag was already set
      - clear_proc_locks should remove a dead process's locks from the
        timeout list
      - the end-of-life calculation for user locks needs to consider that
        ETIMEDOUT is equivalent to -DLM_ECANCEL
      - make initial default timewarn_cs config value visible in configfs
      - change bit position of TIMEOUT_CANCEL flag so it's not copied to
        a remote master node
      - set timestamp on remote lkb's so a lock dump will display the time
        they've been waiting
      Signed-off-by: NDavid Teigland <teigland@redhat.com>
      Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
      84d8cd69
    • D
      [DLM] add lock timeouts and warnings [2/6] · 3ae1acf9
      David Teigland 提交于
      New features: lock timeouts and time warnings.  If the DLM_LKF_TIMEOUT
      flag is set, then the request/conversion will be canceled after waiting
      the specified number of centiseconds (specified per lock).  This feature
      is only available for locks requested through libdlm (can be enabled for
      kernel dlm users if there's a use for it.)
      
      If the new DLM_LSFL_TIMEWARN flag is set when creating the lockspace, then
      a warning message will be sent to userspace (using genetlink) after a
      request/conversion has been waiting for a given number of centiseconds
      (configurable per node).  The time warnings will be used in the future
      to do deadlock detection in userspace.
      Signed-off-by: NDavid Teigland <teigland@redhat.com>
      Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>
      3ae1acf9