1. 09 Sep, 2009 1 commit
  2. 31 Aug, 2009 1 commit
    • H. Peter Anvin's avatar
      mm: remove !NUMA condition from PAGEFLAGS_EXTENDED condition set · a269cca9
      H. Peter Anvin authored
      CONFIG_PAGEFLAGS_EXTENDED disables a trick to conserve pageflags.
      This trick is indended to be enabled when the pressure on page flags
      is very high.
      
      The previous condition was:
      
      -       depends on 64BIT || SPARSEMEM_VMEMMAP || !NUMA || !SPARSEMEM
      
      ... however, the sparsemem code already has a way to crowd out the
      node number from the pageflags, which means that !NUMA actually
      doesn't contribute to hard pageflags exhaustion.
      
      This is required for the new PG_uncached flag to not cause pageflags
      exhaustion on x86_32 + PAE + SPARSEMEM + !NUMA.
      Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      LKML-Reference: <4A9828F4.4040905@zytor.com>
      Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
      Cc: Suresh Siddha <suresh.siddha@intel.com>
      a269cca9
  3. 29 Aug, 2009 1 commit
    • Jan Beulich's avatar
      x86: Fix earlyprintk=dbgp for machines without NX · 47d25003
      Jan Beulich authored
      Since parse_early_param() may (e.g. for earlyprintk=dbgp)
      involve calls to page table manipulation functions (here
      set_fixmap_nocache()), NX hardware support must be determined
      before calling that function (so that __supported_pte_mask gets
      properly set up).
      
      But the call after parse_early_param() can also not go away, as
      that will honor eventual command line specified disabling of
      the NX functionality.
      
      ( This will then just result in whatever mappings got
        established during parse_early_param() having the NX bit set
        despite it being disabled on the command line, but I think
        that's tolerable).
      Signed-off-by: default avatarJan Beulich <jbeulich@novell.com>
      Cc: Yinghai Lu <yhlu.kernel@gmail.com>
      LKML-Reference: <4A97F3BD02000078000121B9@vpn.id2.novell.com>
      [ merged to x86/pat to resolve a conflict. ]
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      47d25003
  4. 27 Aug, 2009 1 commit
  5. 26 Aug, 2009 10 commits
  6. 22 Aug, 2009 1 commit
  7. 21 Aug, 2009 4 commits
    • Suresh Siddha's avatar
      x86, pat/mtrr: Rendezvous all the cpus for MTRR/PAT init · d0af9eed
      Suresh Siddha authored
      SDM Vol 3a section titled "MTRR considerations in MP systems" specifies
      the need for synchronizing the logical cpu's while initializing/updating
      MTRR.
      
      Currently Linux kernel does the synchronization of all cpu's only when
      a single MTRR register is programmed/updated. During an AP online
      (during boot/cpu-online/resume)  where we initialize all the MTRR/PAT registers,
      we don't follow this synchronization algorithm.
      
      This can lead to scenarios where during a dynamic cpu online, that logical cpu
      is initializing MTRR/PAT with cache disabled (cr0.cd=1) etc while other logical
      HT sibling continue to run (also with cache disabled because of cr0.cd=1
      on its sibling).
      
      Starting from Westmere, VMX transitions with cr0.cd=1 don't work properly
      (because of some VMX performance optimizations) and the above scenario
      (with one logical cpu doing VMX activity and another logical cpu coming online)
      can result in system crash.
      
      Fix the MTRR initialization by doing rendezvous of all the cpus. During
      boot and resume, we delay the MTRR/PAT init for APs till all the
      logical cpu's come online and the rendezvous process at the end of AP's bringup,
      will initialize the MTRR/PAT for all AP's.
      
      For dynamic single cpu online, we synchronize all the logical cpus and
      do the MTRR/PAT init on the AP that is coming online.
      Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
      Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      d0af9eed
    • Suresh Siddha's avatar
      generic-ipi: Allow cpus not yet online to call smp_call_function with irqs disabled · 269c861b
      Suresh Siddha authored
      Because of deadlock possiblities smp_call_function() is not allowed to
      be called with interrupts disabled. Add an exception for the cpu not
      yet online, as no one else can send smp call function interrupt to this
      cpu that is not yet online and as such deadlock condition is not possible.
      Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
      Acked-by: default avatarNick Piggin <npiggin@suse.de>
      Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      269c861b
    • Amerigo Wang's avatar
      x86: Fix an incorrect argument of reserve_bootmem() · 3e0e1e9c
      Amerigo Wang authored
      This line looks suspicious, because if this is true, then the
      'flags' parameter of function reserve_bootmem_generic() will be
      unused when !CONFIG_NUMA. I don't think this is what we want.
      Signed-off-by: default avatarWANG Cong <amwang@redhat.com>
      Cc: Yinghai Lu <yinghai@kernel.org>
      Cc: akpm@linux-foundation.org
      LKML-Reference: <20090821083709.5098.52505.sendpatchset@localhost.localdomain>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      3e0e1e9c
    • Xiao Guangrong's avatar
      x86: Fix system crash when loading with "reservetop" parameter · 8126dec3
      Xiao Guangrong authored
      The system will die if the kernel is booted with "reservetop"
      parameter, in present code, parse "reservetop" parameter after
      early_ioremap_init(), and some function still use
      early_ioremap() after it.
      
      The problem is, "reservetop" parameter can modify
      'FIXADDR_TOP', then the virtual address got by early_ioremap()
      is base on old 'FIXADDR_TOP', but the page mapping is base on
      new 'FIXADDR_TOP', it will occur page fault, and the IDT is not
      prepare yet, so, the system is dead.
      
      So, put parse_early_param() in the front of
      early_ioremap_init() in this patch.
      Signed-off-by: default avatarXiao Guangrong <xiaoguangrong@cn.fujitsu.com>
      Cc: yinghai@kernel.org
      Cc: Andrew Morton <akpm@linux-foundation.org>
      LKML-Reference: <4A8D402F.4080805@cn.fujitsu.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      8126dec3
  8. 20 Aug, 2009 4 commits
  9. 18 Aug, 2009 1 commit
    • Jan Beulich's avatar
      i386: Fix section mismatches for init code with !HOTPLUG_CPU · 78b89ecd
      Jan Beulich authored
      Commit 0e83815b changed the
      section the initial_code variable gets allocated in, in an
      attempt to address a section conflict warning. This, however
      created a new section conflict when building without
      HOTPLUG_CPU. The apparently only (reasonable) way to address
      this is to always use __REFDATA.
      
      Once at it, also fix a second section mismatch when not using
      HOTPLUG_CPU.
      Signed-off-by: default avatarJan Beulich <jbeulich@novell.com>
      Cc: Robert Richter <robert.richter@amd.com>
      LKML-Reference: <4A8AE7CD020000780001054B@vpn.id2.novell.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      78b89ecd
  10. 17 Aug, 2009 3 commits
    • Suresh Siddha's avatar
      x86, pat: Allow ISA memory range uncacheable mapping requests · 1adcaafe
      Suresh Siddha authored
      Max Vozeler reported:
      >  Bug 13877 -  bogl-term broken with CONFIG_X86_PAT=y, works with =n
      >
      >  strace of bogl-term:
      >  814   mmap2(NULL, 65536, PROT_READ|PROT_WRITE, MAP_SHARED, 4, 0)
      >				 = -1 EAGAIN (Resource temporarily unavailable)
      >  814   write(2, "bogl: mmaping /dev/fb0: Resource temporarily unavailable\n",
      >	       57) = 57
      
      PAT code maps the ISA memory range as WB in the PAT attribute, so that
      fixed range MTRR registers define the actual memory type (UC/WC/WT etc).
      
      But the upper level is_new_memtype_allowed() API checks are failing,
      as the request here is for UC and the return tracked type is WB (Tracked type is
      WB as MTRR type for this legacy range potentially will be different for each
      4k page).
      
      Fix is_new_memtype_allowed() by always succeeding the ISA address range
      checks, as the null PAT (WB) and def MTRR fixed range register settings
      satisfy the memory type needs of the applications that map the ISA address
      range.
      Reported-and-Tested-by: default avatarMax Vozeler <xam@debian.org>
      Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
      Signed-off-by: default avatarVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
      Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      1adcaafe
    • Ingo Molnar's avatar
      x86, mce: Don't initialize MCEs on unknown CPUs · e412cd25
      Ingo Molnar authored
      An older test-box started hanging at the following point during
      bootup:
      
       [    0.022996] Mount-cache hash table entries: 512
       [    0.024996] Initializing cgroup subsys debug
       [    0.025996] Initializing cgroup subsys cpuacct
       [    0.026995] Initializing cgroup subsys devices
       [    0.027995] Initializing cgroup subsys freezer
       [    0.028995] mce: CPU supports 5 MCE banks
      
      I've bisected it down to commit 4efc0670 ("x86, mce: use 64bit
      machine check code on 32bit"), which utilizes the MCE code on
      32-bit systems too.
      
      The problem is caused by this detail in my config:
      
        # CONFIG_CPU_SUP_INTEL is not set
      
      This disables the quirks in mce_cpu_quirks() but still enables
      MCE support - which then hangs due to the missing quirk
      workaround needed on this CPU:
      
      	if (c->x86 == 6 && c->x86_model < 0x1A && banks > 0)
      		mce_banks[0].init = 0;
      
      The safe solution is to not initialize MCEs if we dont know on
      what CPU we are running (or if that CPU's support code got
      disabled in the config).
      
      Also be a bit more defensive on 32-bit systems: dont do a
      boot-time dump of pending MCEs not just on the specific system
      that we found a problem with (Pentium-M), but earlier ones as
      well.
      
      Now this problem is probably not common and disabling CPU
      support is rare - but still being more defensive in something
      we turned on for a wide range of CPUs is prudent.
      
      Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
      LKML-Reference: Message-ID: <4A88E3E4.40506@jp.fujitsu.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      e412cd25
    • Bartlomiej Zolnierkiewicz's avatar
      x86, mce: don't log boot MCEs on Pentium M (model == 13) CPUs · c7f6fa44
      Bartlomiej Zolnierkiewicz authored
      On my legacy Pentium M laptop (Acer Extensa 2900) I get bogus MCE on a cold
      boot with CONFIG_X86_NEW_MCE enabled, i.e. (after decoding it with mcelog):
      
      MCE 0
      HARDWARE ERROR. This is *NOT* a software problem!
      Please contact your hardware vendor
      CPU 0 BANK 1 MCG status:
      MCi status:
      Error overflow
      Uncorrected error
      Error enabled
      Processor context corrupt
      MCA: Data CACHE Level-1 UNKNOWN Error
      STATUS f200000000000195 MCGSTATUS 0
      
      [ The other STATUS values observed: f2000000000001b5 (... UNKNOWN error)
        and f200000000000115 (... READ Error).
      
        To verify that this is not a CONFIG_X86_NEW_MCE bug I also modified
        the CONFIG_X86_OLD_MCE code (which doesn't log any MCEs) to dump
        content of STATUS MSR before it is cleared during initialization. ]
      
      Since the bogus MCE results in a kernel taint (which in turn disables
      lockdep support) don't log boot MCEs on Pentium M (model == 13) CPUs
      by default ("mce=bootlog" boot parameter can be be used to get the old
      behavior).
      Signed-off-by: default avatarBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
      Reviewed-by: default avatarAndi Kleen <andi@firstfloor.org>
      Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      c7f6fa44
  11. 16 Aug, 2009 2 commits
    • Leonardo Potenza's avatar
      x86: Annotate section mismatch warnings in kernel/apic/x2apic_uv_x.c · 52459ab9
      Leonardo Potenza authored
      The function uv_acpi_madt_oem_check() has been marked __init,
      the struct apic_x2apic_uv_x has been marked __refdata.
      
      The aim is to address the following section mismatch messages:
      
      WARNING: arch/x86/kernel/apic/built-in.o(.data+0x1368): Section mismatch in reference from the variable apic_x2apic_uv_x to the function .cpuinit.text:uv_wakeup_secondary()
      The variable apic_x2apic_uv_x references
      the function __cpuinit uv_wakeup_secondary()
      If the reference is valid then annotate the
      variable with __init* or __refdata (see linux/init.h) or name the variable:
      *driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console,
      
      WARNING: arch/x86/kernel/built-in.o(.data+0x68e8): Section mismatch in reference from the variable apic_x2apic_uv_x to the function .cpuinit.text:uv_wakeup_secondary()
      The variable apic_x2apic_uv_x references
      the function __cpuinit uv_wakeup_secondary()
      If the reference is valid then annotate the
      variable with __init* or __refdata (see linux/init.h) or name the variable:
      *driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console,
      
      WARNING: arch/x86/built-in.o(.text+0x7b36f): Section mismatch in reference from the function uv_acpi_madt_oem_check() to the function .init.text:early_ioremap()
      The function uv_acpi_madt_oem_check() references
      the function __init early_ioremap().
      This is often because uv_acpi_madt_oem_check lacks a __init
      annotation or the annotation of early_ioremap is wrong.
      
      WARNING: arch/x86/built-in.o(.text+0x7b38d): Section mismatch in reference from the function uv_acpi_madt_oem_check() to the function .init.text:early_iounmap()
      The function uv_acpi_madt_oem_check() references
      the function __init early_iounmap().
      This is often because uv_acpi_madt_oem_check lacks a __init
      annotation or the annotation of early_iounmap is wrong.
      
      WARNING: arch/x86/built-in.o(.data+0x8668): Section mismatch in reference from the variable apic_x2apic_uv_x to the function .cpuinit.text:uv_wakeup_secondary()
      The variable apic_x2apic_uv_x references
      the function __cpuinit uv_wakeup_secondary()
      If the reference is valid then annotate the
      variable with __init* or __refdata (see linux/init.h) or name the variable:
      *driver, *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console,
      Signed-off-by: default avatarLeonardo Potenza <lpotenza@inwind.it>
      LKML-Reference: <200908161855.48302.lpotenza@inwind.it>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      52459ab9
    • Hugh Dickins's avatar
      x86, mce: therm_throt: Don't log redundant normality · 4e5c25d4
      Hugh Dickins authored
      0d01f314 "x86, mce: therm_throt
      - change when we print messages" removed redundant
      announcements of "Temperature/speed normal".
      
      They're not worth logging and remove their accompanying
      "Machine check events logged" messages as well from the
      console.
      Signed-off-by: default avatarHugh Dickins <hugh.dickins@tiscali.co.uk>
      Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
      Cc: Andi Kleen <andi@firstfloor.org>
      Cc: Dmitry Torokhov <dtor@mail.ru>
      LKML-Reference: <Pine.LNX.4.64.0908161544100.7929@sister.anvils>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      4e5c25d4
  12. 15 Aug, 2009 1 commit
  13. 13 Aug, 2009 10 commits
    • Linus Torvalds's avatar
      Linux 2.6.31-rc6 · 64f1607f
      Linus Torvalds authored
      64f1607f
    • Linus Torvalds's avatar
      genirq: prevent wakeup of freed irq thread · 2d860ad7
      Linus Torvalds authored
      free_irq() can remove an irqaction while the corresponding interrupt
      is in progress, but free_irq() sets action->thread to NULL
      unconditionally, which might lead to a NULL pointer dereference in
      handle_IRQ_event() when the hard interrupt context tries to wake up
      the handler thread.
      
      Prevent this by moving the thread stop after synchronize_irq(). No
      need to set action->thread to NULL either as action is going to be
      freed anyway.
      
      This fixes a boot crash reported against preempt-rt which uses the
      mainline irq threads code to implement full irq threading.
      
      [ tglx: removed local irqthread variable ]
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      2d860ad7
    • Linus Torvalds's avatar
      Merge branch 'perfcounters-fixes-for-linus' of... · 3493e84d
      Linus Torvalds authored
      Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
      
      * 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
        perf_counter: Report the cloning task as parent on perf_counter_fork()
        perf_counter: Fix an ipi-deadlock
        perf: Rework/fix the whole read vs group stuff
        perf_counter: Fix swcounter context invariance
        perf report: Don't show unresolved DSOs and symbols when -S/-d is used
        perf tools: Add a general option to enable raw sample records
        perf tools: Add a per tracepoint counter attribute to get raw sample
        perf_counter: Provide hw_perf_counter_setup_online() APIs
        perf list: Fix large list output by using the pager
        perf_counter, x86: Fix/improve apic fallback
        perf record: Add missing -C option support for specifying profile cpu
        perf tools: Fix dso__new handle() to handle deleted DSOs
        perf tools: Fix fallback to cplus_demangle() when bfd_demangle() is not available
        perf report: Show the tid too in -D
        perf record: Fix .tid and .pid fill-in when synthesizing events
        perf_counter, x86: Fix generic cache events on P6-mobile CPUs
        perf_counter, x86: Fix lapic printk message
      3493e84d
    • Linus Torvalds's avatar
      Merge branch 'core-fixes-for-linus' of... · 919aa96a
      Linus Torvalds authored
      Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
      
      * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
        futex: Fix handling of bad requeue syscall pairing
        futex: Fix compat_futex to be same as futex for REQUEUE_PI
        locking, sched: Give waitqueue spinlocks their own lockdep classes
        futex: Update futex_q lock_ptr on requeue proxy lock
      919aa96a
    • Linus Torvalds's avatar
      Merge branch 'x86-fixes-for-linus' of... · 1c2ffff4
      Linus Torvalds authored
      Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
      
      * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
        x86: Fix oops in identify_cpu() on CPUs without CPUID
        x86: Clear incorrectly forced X86_FEATURE_LAHF_LM flag
        x86, mce: therm_throt - change when we print messages
        x86: Add reboot quirk for every 5 series MacBook/Pro
      1c2ffff4
    • Linus Torvalds's avatar
      Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2 · bc7af9ba
      Linus Torvalds authored
      * 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2: (22 commits)
        ocfs2: Fix possible deadlock when extending quota file
        ocfs2: keep index within status_map[]
        ocfs2: Initialize the cluster we're writing to in a non-sparse extend
        ocfs2: Remove redundant BUG_ON in __dlm_queue_ast()
        ocfs2/quota: Release lock for error in ocfs2_quota_write.
        ocfs2: Define credit counts for quota operations
        ocfs2: Remove syncjiff field from quota info
        ocfs2: Fix initialization of blockcheck stats
        ocfs2: Zero out padding of on disk dquot structure
        ocfs2: Initialize blocks allocated to local quota file
        ocfs2: Mark buffer uptodate before calling ocfs2_journal_access_dq()
        ocfs2: Make global quota files blocksize aligned
        ocfs2: Use ocfs2_rec_clusters in ocfs2_adjust_adjacent_records.
        ocfs2: Fix deadlock on umount
        ocfs2: Add extra credits and access the modified bh in update_edge_lengths.
        ocfs2: Fail ocfs2_get_block() immediately when a block needs allocation
        ocfs2: Fix error return in ocfs2_write_cluster()
        ocfs2: Fix compilation warning for fs/ocfs2/xattr.c
        ocfs2: Initialize count in aio_write before generic_write_checks
        ocfs2: log the actual return value of ocfs2_file_aio_write()
        ...
      bc7af9ba
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://neil.brown.name/md · d58d2d1a
      Linus Torvalds authored
      * 'for-linus' of git://neil.brown.name/md:
        md: allow upper limit for resync/reshape to be set when array is read-only
        md/raid5: Properly remove excess drives after shrinking a raid5/6
        md/raid5: make sure a reshape restarts at the correct address.
        md/raid5: allow new reshape modes to be restarted in the middle.
        md: never advance 'events' counter by more than 1.
        Remove deadlock potential in md_open
      d58d2d1a
    • Linus Torvalds's avatar
      Merge branch 'sh/for-2.6.31' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6 · 7334219c
      Linus Torvalds authored
      * 'sh/for-2.6.31' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
        sh: fix i2c init order on ap325rxa V2
        sh: fix i2c init order on Migo-R V2
        sh: convert processor device setup functions to arch_initcall()
      7334219c
    • Linus Torvalds's avatar
      Make sock_sendpage() use kernel_sendpage() · e6949583
      Linus Torvalds authored
      kernel_sendpage() does the proper default case handling for when the
      socket doesn't have a native sendpage implementation.
      
      Now, arguably this might be something that we could instead solve by
      just specifying that all protocols should do it themselves at the
      protocol level, but we really only care about the common protocols.
      Does anybody really care about sendpage on something like Appletalk? Not
      likely.
      Acked-by: default avatarDavid S. Miller <davem@davemloft.net>
      Acked-by: default avatarJulien TINNES <julien@cr0.org>
      Acked-by: default avatarTavis Ormandy <taviso@sdf.lonestar.org>
      Cc: stable@kernel.org
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      e6949583
    • Peter Zijlstra's avatar
      perf_counter: Report the cloning task as parent on perf_counter_fork() · 94d5d1b2
      Peter Zijlstra authored
      A bug in (9f498cc5: perf_counter: Full task tracing) makes
      profiling multi-threaded apps it go belly up.
      
      [ output as: (PID:TID):(PPID:PTID) ]
      
       # ./perf report -D | grep FORK
      0x4b0 [0x18]: PERF_EVENT_FORK: (3237:3237):(3236:3236)
      0xa10 [0x18]: PERF_EVENT_FORK: (3237:3238):(3236:3236)
      0xa70 [0x18]: PERF_EVENT_FORK: (3237:3239):(3236:3236)
      0xad0 [0x18]: PERF_EVENT_FORK: (3237:3240):(3236:3236)
      0xb18 [0x18]: PERF_EVENT_FORK: (3237:3241):(3236:3236)
      
      Shows us that the test (27d028de perf report: Update for the new
      FORK/EXIT events) in builtin-report.c:
      
              /*
               * A thread clone will have the same PID for both
               * parent and child.
               */
              if (thread == parent)
                      return 0;
      
      Will clearly fail.
      
      The problem is that perf_counter_fork() reports the actual
      parent, instead of the cloning thread.
      
      Fixing that (with the below patch), yields:
      
       # ./perf report -D | grep FORK
      0x4c8 [0x18]: PERF_EVENT_FORK: (1590:1590):(1589:1589)
      0xbd8 [0x18]: PERF_EVENT_FORK: (1590:1591):(1590:1590)
      0xc80 [0x18]: PERF_EVENT_FORK: (1590:1592):(1590:1590)
      0x3338 [0x18]: PERF_EVENT_FORK: (1590:1593):(1590:1590)
      0x66b0 [0x18]: PERF_EVENT_FORK: (1590:1594):(1590:1590)
      
      Which both makes more sense and doesn't confuse perf report
      anymore.
      Reported-by: default avatarPekka Enberg <penberg@cs.helsinki.fi>
      Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: paulus@samba.org
      Cc: Anton Blanchard <anton@samba.org>
      Cc: Arjan van de Ven <arjan@infradead.org>
      LKML-Reference: <1250172882.5241.62.camel@twins>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      94d5d1b2