1. 29 Mar, 2012 3 commits
    • Len Brown's avatar
      tools turbostat: harden against cpu online/offline · 15aaa346
      Len Brown authored
      
      
      Sometimes users have turbostat running in interval mode
      when they take processors offline/online.
      
      Previously, turbostat would survive, but not gracefully.
      
      Tighten up the error checking so turbostat notices
      changesn sooner, and print just 1 line on change:
      
      turbostat: re-initialized with num_cpus %d
      Signed-off-by: default avatarLen Brown <len.brown@intel.com>
      15aaa346
    • Len Brown's avatar
      tools turbostat: reduce measurement overhead due to IPIs · 88c3281f
      Len Brown authored
      
      
      turbostat uses /dev/cpu/*/msr interface to read MSRs.
      For modern systems, it reads 10 MSR/CPU.  This can
      be observed as 10 "Function Call Interrupts"
      per CPU per sample added to /proc/interrupts.
      
      This overhead is measurable on large idle systems,
      and as Yoquan Song pointed out, it can even trick
      cpuidle into thinking the system is busy.
      
      Here turbostat re-schedules itself in-turn to each
      CPU so that its MSR reads will always be local.
      This replaces the 10 "Function Call Interrupts"
      with a single "Rescheduling interrupt" per sample
      per CPU.
      
      On an idle 32-CPU system, this shifts some residency from
      the shallow c1 state to the deeper c7 state:
      
       # ./turbostat.old -s
         %c0  GHz  TSC    %c1    %c3    %c6    %c7   %pc2   %pc3   %pc6   %pc7
        0.27 1.29 2.29   0.95   0.02   0.00  98.77  20.23   0.00  77.41   0.00
        0.25 1.24 2.29   0.98   0.02   0.00  98.75  20.34   0.03  77.74   0.00
        0.27 1.22 2.29   0.54   0.00   0.00  99.18  20.64   0.00  77.70   0.00
        0.26 1.22 2.29   1.22   0.00   0.00  98.52  20.22   0.00  77.74   0.00
        0.26 1.38 2.29   0.78   0.02   0.00  98.95  20.51   0.05  77.56   0.00
      ^C
       i# ./turbostat.new -s
         %c0  GHz  TSC    %c1    %c3    %c6    %c7   %pc2   %pc3   %pc6   %pc7
        0.27 1.20 2.29   0.24   0.01   0.00  99.49  20.58   0.00  78.20   0.00
        0.27 1.22 2.29   0.25   0.00   0.00  99.48  20.79   0.00  77.85   0.00
        0.27 1.20 2.29   0.25   0.02   0.00  99.46  20.71   0.03  77.89   0.00
        0.28 1.26 2.29   0.25   0.01   0.00  99.46  20.89   0.02  77.67   0.00
        0.27 1.20 2.29   0.24   0.01   0.00  99.48  20.65   0.00  78.04   0.00
      
      cc: Youquan Song <youquan.song@intel.com>
      Signed-off-by: default avatarLen Brown <len.brown@intel.com>
      88c3281f
    • Len Brown's avatar
      tools turbostat: add summary option · e23da037
      Len Brown authored
      
      
      turbostat -s
      cuts down on the amount of output, per user request.
      
      also treak some output whitespace and the man page.
      Signed-off-by: default avatarLen Brown <len.brown@intel.com>
      e23da037
  2. 18 Mar, 2012 2 commits
  3. 17 Mar, 2012 3 commits
    • Linus Torvalds's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net · c579bc7e
      Linus Torvalds authored
      Pull networking changes from David Miller:
       "1) icmp6_dst_alloc() returns NULL instead of ERR_PTR() leading to
           crashes, particularly during shutdown.  Reported by Dave Jones and
           fixed by Eric Dumazet.
      
        2) hyperv and wimax/i2400m return NETDEV_TX_BUSY when they have
           already freed the SKB, which causes crashes as to the caller this
           means requeue the packet.  Fixes from Eric Dumazet.
      
        3) usbnet driver doesn't allocate the right amount of headroom on
           fresh RX SKBs, fix from Eric Dumazet.
      
        4) Fix regression in ip6_mc_find_dev_rcu(), as an RCU lookup it
           abolutely should not take a reference to 'dev', this leads to
           leaks.  Fix from RonQing Li.
      
        5) Fix netfilter ctnetlink race between delete and timeout expiration.
           From Pablo Neira Ayuso.
      
        6) Revert SFQ change which causes regressions, specifically queueing
           to tail can lead to unavoidable flow starvation.  From Eric
           Dumazet.
      
        7) Fix a memory leak and a crash on corrupt firmware files in bnx2x,
           from Michal Schmidt."
      
      * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
        netfilter: ctnetlink: fix race between delete and timeout expiration
        ipv6: Don't dev_hold(dev) in ip6_mc_find_dev_rcu.
        wimax/i2400m: fix erroneous NETDEV_TX_BUSY use
        net/hyperv: fix erroneous NETDEV_TX_BUSY use
        net/usbnet: reserve headroom on rx skbs
        bnx2x: fix memory leak in bnx2x_init_firmware()
        bnx2x: fix a crash on corrupt firmware file
        sch_sfq: revert dont put new flow at the end of flows
        ipv6: fix icmp6_dst_alloc()
      c579bc7e
    • Linus Torvalds's avatar
      Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 96ee0499
      Linus Torvalds authored
      Pull perf fixes from Ingo Molnar.
      
      * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        perf tools, x86: Build perf on older user-space as well
        perf tools: Use scnprintf where applicable
        perf tools: Incorrect use of snprintf results in SEGV
      96ee0499
    • Pablo Neira Ayuso's avatar
      netfilter: ctnetlink: fix race between delete and timeout expiration · a16a1647
      Pablo Neira Ayuso authored
      
      
      Kerin Millar reported hardlockups while running `conntrackd -c'
      in a busy firewall. That system (with several processors) was
      acting as backup in a primary-backup setup.
      
      After several tries, I found a race condition between the deletion
      operation of ctnetlink and timeout expiration. This patch fixes
      this problem.
      Tested-by: default avatarKerin Millar <kerframil@gmail.com>
      Reported-by: default avatarKerin Millar <kerframil@gmail.com>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a16a1647
  4. 16 Mar, 2012 16 commits
  5. 15 Mar, 2012 16 commits