1. 24 May, 2013 6 commits
    • Tejun Heo's avatar
      device_cgroup: simplify cgroup tree walk in propagate_exception() · d591fb56
      Tejun Heo authored
      During a config change, propagate_exception() needs to traverse the
      subtree to update config on the subtree.  Because such config updates
      need to allocate memory, it couldn't directly use
      cgroup_for_each_descendant_pre() which required the whole iteration to
      be contained in a single RCU read critical section.  To work around
      the limitation, propagate_exception() built a linked list of
      descendant cgroups while read-locking RCU and then walked the list
      afterwards, which is safe as the whole iteration is protected by
      devcgroup_mutex.  This works but is cumbersome.
      
      With the recent updates, cgroup iterators now allow dropping RCU read
      lock while iteration is in progress making this workaround no longer
      necessary.  This patch replaces dev_cgroup->propagate_pending list and
      get_online_devcg() with direct cgroup_for_each_descendant_pre() walk.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Cc: Aristeu Rozanski <aris@redhat.com>
      Acked-by: default avatarSerge E. Hallyn <serge.hallyn@ubuntu.com>
      Reviewed-by: default avatarMichal Hocko <mhocko@suse.cz>
      d591fb56
    • Tejun Heo's avatar
      cgroup: update iterators to use cgroup_next_sibling() · 75501a6d
      Tejun Heo authored
      This patch converts cgroup_for_each_child(),
      cgroup_next_descendant_pre/post() and thus
      cgroup_for_each_descendant_pre/post() to use cgroup_next_sibling()
      instead of manually dereferencing ->sibling.next.
      
      The only reason the iterators couldn't allow dropping RCU read lock
      while iteration is in progress was because they couldn't determine the
      next sibling safely once RCU read lock is dropped.  Using
      cgroup_next_sibling() removes that problem and enables all iterators
      to allow dropping RCU read lock in the middle.  Comments are updated
      accordingly.
      
      This makes the iterators easier to use and will simplify controllers.
      
      Note that @cgroup argument is renamed to @cgrp in
      cgroup_for_each_child() because it conflicts with "struct cgroup" used
      in the new macro body.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarSerge E. Hallyn <serge.hallyn@ubuntu.com>
      Reviewed-by: default avatarMichal Hocko <mhocko@suse.cz>
      75501a6d
    • Tejun Heo's avatar
      cgroup: add cgroup->serial_nr and implement cgroup_next_sibling() · 53fa5261
      Tejun Heo authored
      Currently, there's no easy way to find out the next sibling cgroup
      unless it's known that the current cgroup is accessed from the
      parent's children list in a single RCU critical section.  This in turn
      forces all iterators to require whole iteration to be enclosed in a
      single RCU critical section, which sometimes is too restrictive.  This
      patch implements cgroup_next_sibling() which can reliably determine
      the next sibling regardless of the state of the current cgroup as long
      as it's accessible.
      
      It currently is impossible to determine the next sibling after
      dropping RCU read lock because the cgroup being iterated could be
      removed anytime and if RCU read lock is dropped, nothing guarantess
      its ->sibling.next pointer is accessible.  A removed cgroup would
      continue to point to its next sibling for RCU accesses but stop
      receiving updates from the sibling.  IOW, the next sibling could be
      removed and then complete its grace period while RCU read lock is
      dropped, making it unsafe to dereference ->sibling.next after dropping
      and re-acquiring RCU read lock.
      
      This can be solved by adding a way to traverse to the next sibling
      without dereferencing ->sibling.next.  This patch adds a monotonically
      increasing cgroup serial number, cgroup->serial_nr, which guarantees
      that all cgroup->children lists are kept in increasing serial_nr
      order.  A new function, cgroup_next_sibling(), is implemented, which,
      if CGRP_REMOVED is not set on the current cgroup, follows
      ->sibling.next; otherwise, traverses the parent's ->children list
      until it sees a sibling with higher ->serial_nr.
      
      This allows the function to always return the next sibling regardless
      of the state of the current cgroup without adding overhead in the fast
      path.
      
      Further patches will update the iterators to use cgroup_next_sibling()
      so that they allow dropping RCU read lock and blocking while iteration
      is in progress which in turn will be used to simplify controllers.
      
      v2: Typo fix as per Serge.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Acked-by: default avatarSerge E. Hallyn <serge.hallyn@ubuntu.com>
      53fa5261
    • Tejun Heo's avatar
      cgroup: make cgroup_is_removed() static · bdc7119f
      Tejun Heo authored
      cgroup_is_removed() no longer has external users and it shouldn't grow
      any - controllers should deal with cgroup_subsys_state on/offline
      state instead of cgroup removal state.  Make it static.
      
      While at it, make it return bool.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      bdc7119f
    • Tejun Heo's avatar
      Merge branch 'for-3.10-fixes' into for-3.11 · 3f33e64f
      Tejun Heo authored
      Merging to receive 7805d000 ("cgroup: fix a subtle bug in descendant
      pre-order walk") so that further iterator updates can build upon it.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      3f33e64f
    • Tejun Heo's avatar
      cgroup: fix a subtle bug in descendant pre-order walk · 7805d000
      Tejun Heo authored
      When cgroup_next_descendant_pre() initiates a walk, it checks whether
      the subtree root doesn't have any children and if not returns NULL.
      Later code assumes that the subtree isn't empty.  This is broken
      because the subtree may become empty inbetween, which can lead to the
      traversal escaping the subtree by walking to the sibling of the
      subtree root.
      
      There's no reason to have the early exit path.  Remove it along with
      the later assumption that the subtree isn't empty.  This simplifies
      the code a bit and fixes the subtle bug.
      
      While at it, fix the comment of cgroup_for_each_descendant_pre() which
      was incorrectly referring to ->css_offline() instead of
      ->css_online().
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Reviewed-by: default avatarMichal Hocko <mhocko@suse.cz>
      Cc: stable@vger.kernel.org
      7805d000
  2. 14 May, 2013 6 commits
  3. 12 May, 2013 2 commits
    • Linus Torvalds's avatar
      Linux 3.10-rc1 · f722406f
      Linus Torvalds authored
      f722406f
    • Linus Torvalds's avatar
      Merge tag 'trace-fixes-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace · 26b840ae
      Linus Torvalds authored
      Pull tracing/kprobes update from Steven Rostedt:
       "The majority of these changes are from Masami Hiramatsu bringing
        kprobes up to par with the latest changes to ftrace (multi buffering
        and the new function probes).
      
        He also discovered and fixed some bugs in doing so.  When pulling in
        his patches, I also found a few minor bugs as well and fixed them.
      
        This also includes a compile fix for some archs that select the ring
        buffer but not tracing.
      
        I based this off of the last patch you took from me that fixed the
        merge conflict error, as that was the commit that had all the changes
        I needed for this set of changes."
      
      * tag 'trace-fixes-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
        tracing/kprobes: Support soft-mode disabling
        tracing/kprobes: Support ftrace_event_file base multibuffer
        tracing/kprobes: Pass trace_probe directly from dispatcher
        tracing/kprobes: Increment probe hit-count even if it is used by perf
        tracing/kprobes: Use bool for retprobe checker
        ftrace: Fix function probe when more than one probe is added
        ftrace: Fix the output of enabled_functions debug file
        ftrace: Fix locking in register_ftrace_function_probe()
        tracing: Add helper function trace_create_new_event() to remove duplicate code
        tracing: Modify soft-mode only if there's no other referrer
        tracing: Indicate enabled soft-mode in enable file
        tracing/kprobes: Fix to increment return event probe hit-count
        ftrace: Cleanup regex_lock and ftrace_lock around hash updating
        ftrace, kprobes: Fix a deadlock on ftrace_regex_lock
        ftrace: Have ftrace_regex_write() return either read or error
        tracing: Return error if register_ftrace_function_probe() fails for event_enable_func()
        tracing: Don't succeed if event_enable_func did not register anything
        ring-buffer: Select IRQ_WORK
      26b840ae
  4. 11 May, 2013 4 commits
    • Linus Torvalds's avatar
      Merge tag 'stable/for-linus-3.10-rc0-tag-two' of... · 607eeb0b
      Linus Torvalds authored
      Merge tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
      
      Pull Xen bug-fixes from Konrad Rzeszutek Wilk:
       - More fixes in the vCPU PVHVM hotplug path.
       - Add more documentation.
       - Fix various ARM related issues in the Xen generic drivers.
       - Updates in the xen-pciback driver per Bjorn's updates.
       - Mask the x2APIC feature for PV guests.
      
      * tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
        xen/pci: Used cached MSI-X capability offset
        xen/pci: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASK
        xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST
        xen: mask x2APIC feature in PV
        xen: SWIOTLB is only used on x86
        xen/spinlock: Fix check from greater than to be also be greater or equal to.
        xen/smp/pvhvm: Don't point per_cpu(xen_vpcu, 33 and larger) to shared_info
        xen/vcpu: Document the xen_vcpu_info and xen_vcpu
        xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.
      607eeb0b
    • Linus Torvalds's avatar
      Merge tag 'scsi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi · 4c444501
      Linus Torvalds authored
      Pull second SCSI update from James "Jaj B" Bottomley:
       "This is the final round of SCSI patches for the merge window.  It
        consists mostly of driver updates (bnx2fc, ibmfc, fnic, lpfc,
        be2iscsi, pm80xx, qla4x and ipr).
      
        There's also the power management updates that complete the patches in
        Jens' tree, an iscsi refcounting problem fix from the last pull, some
        dif handling in scsi_debug fixes, a few nice code cleanups and an
        error handling busy bug fix."
      
      * tag 'scsi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (92 commits)
        [SCSI] qla2xxx: Update firmware link in Kconfig file.
        [SCSI] iscsi class, qla4xxx: fix sess/conn refcounting when find fns are used
        [SCSI] sas: unify the pointlessly separated enums sas_dev_type and sas_device_type
        [SCSI] pm80xx: thermal, sas controller config and error handling update
        [SCSI] pm80xx: NCQ error handling changes
        [SCSI] pm80xx: WWN Modification for PM8081/88/89 controllers
        [SCSI] pm80xx: Changed module name and debug messages update
        [SCSI] pm80xx: Firmware flash memory free fix, with addition of new memory region for it
        [SCSI] pm80xx: SPC new firmware changes for device id 0x8081 alone
        [SCSI] pm80xx: Added SPCv/ve specific hardware functionalities and relevant changes in common files
        [SCSI] pm80xx: MSI-X implementation for using 64 interrupts
        [SCSI] pm80xx: Updated common functions common for SPC and SPCv/ve
        [SCSI] pm80xx: Multiple inbound/outbound queue configuration
        [SCSI] pm80xx: Added SPCv/ve specific ids, variables and modify for SPC
        [SCSI] lpfc: fix up Kconfig dependencies
        [SCSI] Handle MLQUEUE busy response in scsi_send_eh_cmnd
        [SCSI] sd: change to auto suspend mode
        [SCSI] sd: use REQ_PM in sd's runtime suspend operation
        [SCSI] qla4xxx: Fix iocb_cnt calculation in qla4xxx_send_mbox_iocb()
        [SCSI] ufs: Correct the expected data transfersize
        ...
      4c444501
    • Linus Torvalds's avatar
      Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux · ac4e0109
      Linus Torvalds authored
      Pull idle update from Len Brown:
       "Add support for new Haswell-ULT CPU idle power states"
      
      * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
        intel_idle: initial C8, C9, C10 support
        tools/power turbostat: display C8, C9, C10 residency
      ac4e0109
    • Linus Torvalds's avatar
      Merge git://git.infradead.org/users/eparis/audit · c4cc75c3
      Linus Torvalds authored
      Pull audit changes from Eric Paris:
       "Al used to send pull requests every couple of years but he told me to
        just start pushing them to you directly.
      
        Our touching outside of core audit code is pretty straight forward.  A
        couple of interface changes which hit net/.  A simple argument bug
        calling audit functions in namei.c and the removal of some assembly
        branch prediction code on ppc"
      
      * git://git.infradead.org/users/eparis/audit: (31 commits)
        audit: fix message spacing printing auid
        Revert "audit: move kaudit thread start from auditd registration to kaudit init"
        audit: vfs: fix audit_inode call in O_CREAT case of do_last
        audit: Make testing for a valid loginuid explicit.
        audit: fix event coverage of AUDIT_ANOM_LINK
        audit: use spin_lock in audit_receive_msg to process tty logging
        audit: do not needlessly take a lock in tty_audit_exit
        audit: do not needlessly take a spinlock in copy_signal
        audit: add an option to control logging of passwords with pam_tty_audit
        audit: use spin_lock_irqsave/restore in audit tty code
        helper for some session id stuff
        audit: use a consistent audit helper to log lsm information
        audit: push loginuid and sessionid processing down
        audit: stop pushing loginid, uid, sessionid as arguments
        audit: remove the old depricated kernel interface
        audit: make validity checking generic
        audit: allow checking the type of audit message in the user filter
        audit: fix build break when AUDIT_DEBUG == 2
        audit: remove duplicate export of audit_enabled
        Audit: do not print error when LSMs disabled
        ...
      c4cc75c3
  5. 10 May, 2013 22 commits