1. 24 Oct, 2006 1 commit
    • Eric W. Biederman's avatar
      [PATCH] x86-64: Only look at per_cpu data for online cpus. · 70a0a535
      Eric W. Biederman authored
      
      
      When I generalized __assign_irq_vector I failed to pay attention
      to what happens when you access a per cpu data structure for
      a cpu that is not online.   It is an undefined case making any
      code that does it have undefined behavior as well.
      
      The code still needs to be able to allocate a vector across cpus
      that are not online to properly handle combinations like lowest
      priority interrupt delivery and cpu_hotplug.  Not that we can do
      that today but the infrastructure shouldn't prevent it.
      
      So this patch updates the places where we touch per cpu data
      to only touch online cpus, it makes cpu vector allocation
      an atomic operation with respect to cpu hotplug, and it updates
      the cpu start code to properly initialize vector_irq so we
      don't have inconsistencies.
      Signed-off-by: default avatarEric W. Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndi Kleen <ak@suse.de>
      70a0a535
  2. 26 Sep, 2006 6 commits
  3. 10 Jul, 2006 1 commit
  4. 03 Jul, 2006 1 commit
  5. 30 Jun, 2006 1 commit
  6. 27 Jun, 2006 1 commit
    • Siddha, Suresh B's avatar
      [PATCH] sched: mc/smt power savings sched policy · 5c45bf27
      Siddha, Suresh B authored
      
      
      sysfs entries 'sched_mc_power_savings' and 'sched_smt_power_savings' in
      /sys/devices/system/cpu/ control the MC/SMT power savings policy for the
      scheduler.
      
      Based on the values (1-enable, 0-disable) for these controls, sched groups
      cpu power will be determined for different domains.  When power savings
      policy is enabled and under light load conditions, scheduler will minimize
      the physical packages/cpu cores carrying the load and thus conserving
      power(with a perf impact based on the workload characteristics...  see OLS
      2005 CMP kernel scheduler paper for more details..)
      Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Nick Piggin <nickpiggin@yahoo.com.au>
      Cc: Con Kolivas <kernel@kolivas.org>
      Cc: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      5c45bf27
  7. 26 Jun, 2006 3 commits
  8. 31 Mar, 2006 1 commit
    • OGAWA Hirofumi's avatar
      [PATCH] Don't pass boot parameters to argv_init[] · 9b41046c
      OGAWA Hirofumi authored
      
      
      The boot cmdline is parsed in parse_early_param() and
      parse_args(,unknown_bootoption).
      
      And __setup() is used in obsolete_checksetup().
      
      	start_kernel()
      		-> parse_args()
      			-> unknown_bootoption()
      				-> obsolete_checksetup()
      
      If __setup()'s callback (->setup_func()) returns 1 in
      obsolete_checksetup(), obsolete_checksetup() thinks a parameter was
      handled.
      
      If ->setup_func() returns 0, obsolete_checksetup() tries other
      ->setup_func().  If all ->setup_func() that matched a parameter returns 0,
      a parameter is seted to argv_init[].
      
      Then, when runing /sbin/init or init=app, argv_init[] is passed to the app.
      If the app doesn't ignore those arguments, it will warning and exit.
      
      This patch fixes a wrong usage of it, however fixes obvious one only.
      Signed-off-by: default avatarOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      9b41046c
  9. 27 Mar, 2006 1 commit
    • Siddha, Suresh B's avatar
      [PATCH] sched: new sched domain for representing multi-core · 1e9f28fa
      Siddha, Suresh B authored
      
      
      Add a new sched domain for representing multi-core with shared caches
      between cores.  Consider a dual package system, each package containing two
      cores and with last level cache shared between cores with in a package.  If
      there are two runnable processes, with this appended patch those two
      processes will be scheduled on different packages.
      
      On such systems, with this patch we have observed 8% perf improvement with
      specJBB(2 warehouse) benchmark and 35% improvement with CFP2000 rate(with 2
      users).
      
      This new domain will come into play only on multi-core systems with shared
      caches.  On other systems, this sched domain will be removed by domain
      degeneration code.  This new domain can be also used for implementing power
      savings policy (see OLS 2005 CMP kernel scheduler paper for more details..
      I will post another patch for power savings policy soon)
      
      Most of the arch/* file changes are for cpu_coregroup_map() implementation.
      Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
      Cc: Ingo Molnar <mingo@elte.hu>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      1e9f28fa
  10. 26 Feb, 2006 2 commits
  11. 07 Feb, 2006 1 commit
  12. 05 Feb, 2006 1 commit
  13. 04 Feb, 2006 1 commit
  14. 12 Jan, 2006 2 commits
  15. 11 Jan, 2006 7 commits
  16. 12 Dec, 2005 1 commit
  17. 14 Nov, 2005 3 commits
    • Siddha, Suresh B's avatar
      [PATCH] x86-64/i386: Intel HT, Multi core detection fixes · 94605eff
      Siddha, Suresh B authored
      Fields obtained through cpuid vector 0x1(ebx[16:23]) and
      vector 0x4(eax[14:25], eax[26:31]) indicate the maximum values and might not
      always be the same as what is available and what OS sees.  So make sure
      "siblings" and "cpu cores" values in /proc/cpuinfo reflect the values as seen
      by OS instead of what cpuid instruction says. This will also fix the buggy BIOS
      cases (for example where cpuid on a single core cpu says there are "2" siblings,
      even when HT is disabled in the BIOS.
      http://bugzilla.kernel.org/show_bug.cgi?id=4359
      
      )
      Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
      Signed-off-by: default avatarAndi Kleen <ak@suse.de>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      94605eff
    • Andi Kleen's avatar
      [PATCH] x86_64: New heuristics to find out hotpluggable CPUs. · 420f8f68
      Andi Kleen authored
      
      
      With a NR_CPUS==128 kernel with CPU hotplug enabled we would waste 4MB
      on per CPU data of all possible CPUs.  The reason was that HOTPLUG
      always set up possible map to NR_CPUS cpus and then we need to allocate
      that much (each per CPU data is roughly ~32k now)
      
      The underlying problem is that ACPI didn't tell us how many hotplug CPUs
      the platform supports.  So the old code just assumed all, which would
      lead to this memory wastage.
      
      This implements some new heuristics:
      
       - If the BIOS specified disabled CPUs in the ACPI/mptables assume they
         can be enabled later (this is bending the ACPI specification a bit,
         but seems like a obvious extension)
       - The user can overwrite it with a new additionals_cpus=NUM option
       - Otherwise use half of the available CPUs or 2, whatever is more.
      
      Cc: ashok.raj@intel.com
      Cc: len.brown@intel.com
      Signed-off-by: default avatarAndi Kleen <ak@suse.de>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      420f8f68
    • Siddha, Suresh B's avatar
      [PATCH] x86_64: Unmap NULL during early bootup · f6c2e333
      Siddha, Suresh B authored
      
      
      We should zap the low mappings, as soon as possible, so that we can catch
      kernel bugs more effectively. Previously early boot had NULL mapped
      and didn't trap on NULL references.
      
      This patch introduces boot_level4_pgt, which will always have low identity
      addresses mapped.  Druing boot, all the processors will use this as their
      level4 pgt.  On BP, we will switch to init_level4_pgt as soon as we enter C
      code and zap the low mappings as soon as we are done with the usage of
      identity low mapped addresses.  On AP's we will zap the low mappings as
      soon as we jump to C code.
      Signed-off-by: default avatarSuresh Siddha <suresh.b.siddha@intel.com>
      Signed-off-by: default avatarAshok Raj <ashok.raj@intel.com>
      Signed-off-by: default avatarAndi Kleen <ak@suse.de>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      f6c2e333
  18. 09 Nov, 2005 1 commit
    • Nick Piggin's avatar
      [PATCH] sched: disable preempt in idle tasks · 5bfb5d69
      Nick Piggin authored
      
      
      Run idle threads with preempt disabled.
      
      Also corrected a bugs in arm26's cpu_idle (make it actually call schedule()).
      How did it ever work before?
      
      Might fix the CPU hotplugging hang which Nigel Cunningham noted.
      
      We think the bug hits if the idle thread is preempted after checking
      need_resched() and before going to sleep, then the CPU offlined.
      
      After calling stop_machine_run, the CPU eventually returns from preemption and
      into the idle thread and goes to sleep.  The CPU will continue executing
      previous idle and have no chance to call play_dead.
      
      By disabling preemption until we are ready to explicitly schedule, this bug is
      fixed and the idle threads generally become more robust.
      
      From: alexs <ashepard@u.washington.edu>
      
        PPC build fix
      
      From: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
      
        MIPS build fix
      Signed-off-by: default avatarNick Piggin <npiggin@suse.de>
      Signed-off-by: default avatarYoichi Yuasa <yuasa@hh.iij4u.or.jp>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      5bfb5d69
  19. 07 Nov, 2005 1 commit
  20. 10 Oct, 2005 1 commit
  21. 12 Sep, 2005 3 commits