]> pilppa.com Git - linux-2.6-omap-h63xx.git/log
linux-2.6-omap-h63xx.git
16 years agosched: fair-group: SMP-nice for group scheduling
Peter Zijlstra [Sat, 19 Apr 2008 17:45:00 +0000 (19:45 +0200)]
sched: fair-group: SMP-nice for group scheduling

Implement SMP nice support for the full group hierarchy.

On each load-balance action, compile a sched_domain wide view of the full
task_group tree. We compute the domain wide view when walking down the
hierarchy, and readjust the weights when walking back up.

After collecting and readjusting the domain wide view, we try to balance the
tasks within the task_groups. The current approach is a naively balance each
task group until we've moved the targeted amount of load.

Inspired by Srivatsa Vaddsgiri's previous code and Abhishek Chandra's H-SMP
paper.

XXX: there will be some numerical issues due to the limited nature of
     SCHED_LOAD_SCALE wrt to representing a task_groups influence on the
     total weight. When the tree is deep enough, or the task weight small
     enough, we'll run out of bits.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
CC: Abhishek Chandra <chandra@cs.umn.edu>
CC: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched, cpuset: customize sched domains, core
Hidetoshi Seto [Tue, 15 Apr 2008 05:04:23 +0000 (14:04 +0900)]
sched, cpuset: customize sched domains, core

[rebased for sched-devel/latest]

 - Add a new cpuset file, having levels:
     sched_relax_domain_level

 - Modify partition_sched_domains() and build_sched_domains()
   to take attributes parameter passed from cpuset.

 - Fill newidle_idx for node domains which currently unused but
   might be required if sched_relax_domain_level become higher.

 - We can change the default level by boot option 'relax_domain_level='.

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched, cpuset: customize sched domains, docs
Hidetoshi Seto [Tue, 15 Apr 2008 05:03:17 +0000 (14:03 +0900)]
sched, cpuset: customize sched domains, docs

This patch introduces new feature of cpuset - sched domain customization.

This version provides a per-cpuset file 'sched_relax_domain_level' that
enable us to change the searching range of scheduler, which used to limit
how many cpus the scheduler searches at some schedule events, such as
wakening task and running out of runqueue.

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: prepatory code movement
Peter Zijlstra [Sat, 19 Apr 2008 17:45:00 +0000 (19:45 +0200)]
sched: prepatory code movement

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: rt: multi level group constraints
Peter Zijlstra [Sat, 19 Apr 2008 17:45:00 +0000 (19:45 +0200)]
sched: rt: multi level group constraints

multi level rt constraints

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: task_group hierarchy
Peter Zijlstra [Sat, 19 Apr 2008 17:45:00 +0000 (19:45 +0200)]
sched: task_group hierarchy

Add the full parent<->child relation thing into task_groups as well.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: fix the task_group hierarchy for UID grouping
Peter Zijlstra [Sat, 19 Apr 2008 17:45:00 +0000 (19:45 +0200)]
sched: fix the task_group hierarchy for UID grouping

UID grouping doesn't actually have a task_group representing the root of
the task_group tree. Add one.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: allow the group scheduler to have multiple levels
Dhaval Giani [Sat, 19 Apr 2008 17:44:59 +0000 (19:44 +0200)]
sched: allow the group scheduler to have multiple levels

This patch makes the group scheduler multi hierarchy aware.

[a.p.zijlstra@chello.nl: rt-parts and assorted fixes]
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: mix tasks and groups
Dhaval Giani [Sat, 19 Apr 2008 17:44:59 +0000 (19:44 +0200)]
sched: mix tasks and groups

This patch allows tasks and groups to exist in the same cfs_rq. With this
change the CFS group scheduling follows a 1/(M+N) model from a 1/(1+N)
fairness model where M tasks and N groups exist at the cfs_rq level.

[a.p.zijlstra@chello.nl: rt bits and assorted fixes]
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: fix checks
Ingo Molnar [Tue, 25 Mar 2008 12:51:45 +0000 (13:51 +0100)]
sched: fix checks

Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: old sleeper bonus
Peter Zijlstra [Wed, 19 Mar 2008 10:43:36 +0000 (11:43 +0100)]
sched: old sleeper bonus

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: add new set_cpus_allowed_ptr function
Mike Travis [Wed, 26 Mar 2008 21:23:49 +0000 (14:23 -0700)]
sched: add new set_cpus_allowed_ptr function

Add a new function that accepts a pointer to the "newly allowed cpus"
cpumask argument.

int set_cpus_allowed_ptr(struct task_struct *p, const cpumask_t *new_mask)

The current set_cpus_allowed() function is modified to use the above
but this does not result in an ABI change.  And with some compiler
optimization help, it may not introduce any additional overhead.

Additionally, to enforce the read only nature of the new_mask arg, the
"const" property is migrated to sub-functions called by set_cpus_allowed.
This silences compiler warnings.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agoinit: move setup of nr_cpu_ids to as early as possible
Mike Travis [Wed, 26 Mar 2008 21:23:48 +0000 (14:23 -0700)]
init: move setup of nr_cpu_ids to as early as possible

Move the setting of nr_cpu_ids from sched_init() to start_kernel()
so that it's available as early as possible.

Note that an arch has the option of setting it even earlier if need be,
but it should not result in a different value than the setup_nr_cpu_ids()
function.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: remove another cpumask_t variable from stack
Mike Travis [Tue, 15 Apr 2008 23:35:52 +0000 (16:35 -0700)]
sched: remove another cpumask_t variable from stack

    * Remove another cpumask_t variable from stack that was missed in the
      last kernel_sched_c updates.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agocpumask: add show cpu map functions
Mike Travis [Tue, 8 Apr 2008 18:43:04 +0000 (11:43 -0700)]
cpumask: add show cpu map functions

  * Add cpu_sysdev_class functions to display the following maps
    with cpulist_scnprintf().

cpu_online_map
cpu_present_map
cpu_possible_map

  * Small change to include/linux/sysdev.h to allow the attribute
    name and label to be different (to avoid collision with the
    "attr_online" entry for bringing cpus on- and off-line.)

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agocpumask: use new cpus_scnprintf function
Mike Travis [Tue, 8 Apr 2008 18:43:03 +0000 (11:43 -0700)]
cpumask: use new cpus_scnprintf function

  * Cleaned up references to cpumask_scnprintf() and added new
    cpulist_scnprintf() interfaces where appropriate.

  * Fix some small bugs (or code efficiency improvments) for various uses
    of cpumask_scnprintf.

  * Clean up some checkpatch errors.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agox86: modify show_shared_cpu_map in intel_cacheinfo
Mike Travis [Tue, 8 Apr 2008 18:43:02 +0000 (11:43 -0700)]
x86: modify show_shared_cpu_map in intel_cacheinfo

  * Removed kmalloc (or local array) in show_shared_cpu_map().

  * Added show_shared_cpu_list() function.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agox86: convert cpumask_of_cpu macro to allocated array
Mike Travis [Sat, 5 Apr 2008 01:11:01 +0000 (18:11 -0700)]
x86: convert cpumask_of_cpu macro to allocated array

  * Here is a simple patch to use an allocated array of cpumasks to
    represent cpumask_of_cpu() instead of constructing one on the stack.
    It's based on the Kconfig option "HAVE_CPUMASK_OF_CPU_MAP" which is
    currently only set for x86_64 SMP.  Otherwise the the existing
    cpumask_of_cpu() is used but has been changed to produce an lvalue
    so a pointer to it can be used.

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agocpumask: add CPU_MASK_ALL_PTR macro
Mike Travis [Sat, 5 Apr 2008 01:11:02 +0000 (18:11 -0700)]
cpumask: add CPU_MASK_ALL_PTR macro

  * Add a static cpumask_t variable "CPU_MASK_ALL_PTR" to use as
    a pointer reference to CPU_MASK_ALL.  This reduces where possible
    the instances where CPU_MASK_ALL allocates and fills a large
    array on the stack.  Used only if NR_CPUS > BITS_PER_LONG.

  * Change init/main.c to use new set_cpus_allowed_ptr().

Depends on:
[sched-devel]: sched: add new set_cpus_allowed_ptr function

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agocpumask: reduce stack usage in SD_x_INIT initializers
Mike Travis [Sat, 5 Apr 2008 01:11:11 +0000 (18:11 -0700)]
cpumask: reduce stack usage in SD_x_INIT initializers

  * Remove empty cpumask_t (and all non-zero/non-null) variables
    in SD_*_INIT macros.  Use memset(0) to clear.  Also, don't
    inline the initializer functions to save on stack space in
    build_sched_domains().

  * Merge change to include/linux/topology.h that uses the new
    node_to_cpumask_ptr function in the nr_cpus_node macro into
    this patch.

Depends on:
[mm-patch]: asm-generic-add-node_to_cpumask_ptr-macro.patch
[sched-devel]: sched: add new set_cpus_allowed_ptr function

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agonodemask: use new node_to_cpumask_ptr function
Mike Travis [Sat, 5 Apr 2008 01:11:10 +0000 (18:11 -0700)]
nodemask: use new node_to_cpumask_ptr function

  * Use new node_to_cpumask_ptr.  This creates a pointer to the
    cpumask for a given node.  This definition is in mm patch:

asm-generic-add-node_to_cpumask_ptr-macro.patch

  * Use new set_cpus_allowed_ptr function.

Depends on:
[mm-patch]: asm-generic-add-node_to_cpumask_ptr-macro.patch
[sched-devel]: sched: add new set_cpus_allowed_ptr function
[x86/latest]: x86: add cpus_scnprintf function

Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Greg Banks <gnb@melbourne.sgi.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agogeneric: reduce stack pressure in sched_affinity
Mike Travis [Sat, 5 Apr 2008 01:11:08 +0000 (18:11 -0700)]
generic: reduce stack pressure in sched_affinity

  * Modify sched_affinity functions to pass cpumask_t variables by reference
    instead of by value.

  * Use new set_cpus_allowed_ptr function.

Depends on:
[sched-devel]: sched: add new set_cpus_allowed_ptr function

Cc: Paul Jackson <pj@sgi.com>
Cc: Cliff Wickman <cpw@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agocpuset: modify cpuset_set_cpus_allowed to use cpumask pointer
Mike Travis [Sat, 5 Apr 2008 01:11:07 +0000 (18:11 -0700)]
cpuset: modify cpuset_set_cpus_allowed to use cpumask pointer

  * Modify cpuset_cpus_allowed to return the currently allowed cpuset
    via a pointer argument instead of as the function return value.

  * Use new set_cpus_allowed_ptr function.

  * Cleanup CPU_MASK_ALL and NODE_MASK_ALL uses.

Depends on:
[sched-devel]: sched: add new set_cpus_allowed_ptr function

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agogeneric: use new set_cpus_allowed_ptr function
Mike Travis [Sat, 5 Apr 2008 01:11:06 +0000 (18:11 -0700)]
generic: use new set_cpus_allowed_ptr function

  * Use new set_cpus_allowed_ptr() function added by previous patch,
    which instead of passing the "newly allowed cpus" cpumask_t arg
    by value,  pass it by pointer:

    -int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
    +int set_cpus_allowed_ptr(struct task_struct *p, const cpumask_t *new_mask)

  * Modify CPU_MASK_ALL

Depends on:
[sched-devel]: sched: add new set_cpus_allowed_ptr function

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agox86: use new set_cpus_allowed_ptr function
Mike Travis [Sat, 5 Apr 2008 01:11:05 +0000 (18:11 -0700)]
x86: use new set_cpus_allowed_ptr function

  * Use new set_cpus_allowed_ptr() function added by previous patch,
    which instead of passing the "newly allowed cpus" cpumask_t arg
    by value,  pass it by pointer:

    -int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
    +int set_cpus_allowed_ptr(struct task_struct *p, const cpumask_t *new_mask)

  * Cleanup uses of CPU_MASK_ALL.

  * Collapse other NR_CPUS changes to arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
    Use pointers to cpumask_t arguments whenever possible.

Depends on:
[sched-devel]: sched: add new set_cpus_allowed_ptr function

Cc: Len Brown <len.brown@intel.com>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: remove fixed NR_CPUS sized arrays in kernel_sched_c
Mike Travis [Sat, 5 Apr 2008 01:11:04 +0000 (18:11 -0700)]
sched: remove fixed NR_CPUS sized arrays in kernel_sched_c

 * Change fixed size arrays to per_cpu variables or dynamically allocated
   arrays in sched_init() and sched_init_smp().

     (1) static struct sched_entity *init_sched_entity_p[NR_CPUS];
     (1) static struct cfs_rq *init_cfs_rq_p[NR_CPUS];
     (1) static struct sched_rt_entity *init_sched_rt_entity_p[NR_CPUS];
     (1) static struct rt_rq *init_rt_rq_p[NR_CPUS];
 static struct sched_group **sched_group_nodes_bycpu[NR_CPUS];

     (1) - these arrays are allocated via alloc_bootmem_low()

 * Change sched_domain_debug_one() to use cpulist_scnprintf instead of
   cpumask_scnprintf.  This reduces the output buffer required and improves
   readability when large NR_CPU count machines arrive.

 * In sched_create_group() we allocate new arrays based on nr_cpu_ids.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agocpumask: Cleanup more uses of CPU_MASK and NODE_MASK
Mike Travis [Sat, 5 Apr 2008 01:11:12 +0000 (18:11 -0700)]
cpumask: Cleanup more uses of CPU_MASK and NODE_MASK

 *  Replace usages of CPU_MASK_NONE, CPU_MASK_ALL, NODE_MASK_NONE,
    NODE_MASK_ALL to reduce stack requirements for large NR_CPUS
    and MAXNODES counts.

 *  In some cases, the cpumask variable was initialized but then overwritten
    with another value.  This is the case for changes like this:

    -       cpumask_t oldmask = CPU_MASK_ALL;
    +       cpumask_t oldmask;

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agonuma: move large array from stack to _initdata section
Mike Travis [Sat, 5 Apr 2008 01:11:09 +0000 (18:11 -0700)]
numa: move large array from stack to _initdata section

  * Move large array "struct bootnode nodes" from stack to _initdata
    section to reduce amount of stack space required.

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agoasm-generic: add node_to_cpumask_ptr macro
Mike Travis [Mon, 31 Mar 2008 15:41:55 +0000 (08:41 -0700)]
asm-generic: add node_to_cpumask_ptr macro

Create a simple macro to always return a pointer to the node_to_cpumask(node)
value.  This relies on compiler optimization to remove the extra indirection:

    #define node_to_cpumask_ptr(v, node)  \
    cpumask_t _##v = node_to_cpumask(node), *v = &_##v

For those systems with a large cpumask size, then a true pointer
to the array element can be used:

    #define node_to_cpumask_ptr(v, node) \
    cpumask_t *v = &(node_to_cpumask_map[node])

A node_to_cpumask_ptr_next() macro is provided to access another
node_to_cpumask value.

The other change is to always include asm-generic/topology.h moving the
ifdef CONFIG_NUMA to this same file.

Note: there are no references to either of these new macros in this patch,
only the definition.

Based on 2.6.25-rc5-mm1

# alpha
Cc: Richard Henderson <rth@twiddle.net>
# fujitsu
Cc: David Howells <dhowells@redhat.com>
# ia64
Cc: Tony Luck <tony.luck@intel.com>
# powerpc
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
# sparc
Cc: David S. Miller <davem@davemloft.net>
Cc: William L. Irwin <wli@holomorphy.com>
# x86
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agox86: oprofile: remove NR_CPUS arrays in arch/x86/oprofile/nmi_int.c
Mike Travis [Tue, 25 Mar 2008 22:06:59 +0000 (15:06 -0700)]
x86: oprofile: remove NR_CPUS arrays in arch/x86/oprofile/nmi_int.c

Change the following arrays sized by NR_CPUS to be PERCPU variables:

static struct op_msrs cpu_msrs[NR_CPUS];
static unsigned long saved_lvtpc[NR_CPUS];

Also some minor complaints from checkpatch.pl fixed.

Based on:
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86.git

All changes were transparent except for:

 static void nmi_shutdown(void)
 {
+ struct op_msrs *msrs = &__get_cpu_var(cpu_msrs);
  nmi_enabled = 0;
  on_each_cpu(nmi_cpu_shutdown, NULL, 0, 1);
  unregister_die_notifier(&profile_exceptions_nb);
- model->shutdown(cpu_msrs);
+ model->shutdown(msrs);
  free_msrs();
 }

The existing code passed a reference to cpu 0's instance of struct op_msrs
to model->shutdown, whilst the other functions are passed a reference to
<this cpu's> instance of a struct op_msrs.  This seemed to be a bug to me
even though as long as cpu 0 and <this cpu> are of the same type it would
have the same effect...?

Cc: Philippe Elie <phil.el@wanadoo.fr>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agox86: reduce memory and stack usage in intel_cacheinfo
Mike Travis [Tue, 25 Mar 2008 22:06:56 +0000 (15:06 -0700)]
x86: reduce memory and stack usage in intel_cacheinfo

* Change the following static arrays sized by NR_CPUS to
  per_cpu data variables:

_cpuid4_info *cpuid4_info[NR_CPUS];
_index_kobject *index_kobject[NR_CPUS];
kobject * cache_kobject[NR_CPUS];

* Remove the local NR_CPUS array with a kmalloc'd region in
  show_shared_cpu_map().

Also some minor complaints from checkpatch.pl fixed.

Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agocpumask: add cpumask_scnprintf_len function
Mike Travis [Tue, 25 Mar 2008 22:06:55 +0000 (15:06 -0700)]
cpumask: add cpumask_scnprintf_len function

Add a new function cpumask_scnprintf_len() to return the number of
characters needed to display "len" cpumask bits.  The current method
of allocating NR_CPUS bytes is incorrect as what's really needed is
9 characters per 32-bit word of cpumask bits (8 hex digits plus the
seperator [','] or the terminating NULL.)  This function provides the
caller the means to allocate the correct string length.

Cc: Paul Jackson <pj@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: fix cpus_allowed settings
Gregory Haskins [Tue, 12 Feb 2008 18:30:05 +0000 (13:30 -0500)]
sched: fix cpus_allowed settings

Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Acked-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: allow cpuacct stats to be reset
Dhaval Giani [Fri, 29 Feb 2008 04:32:44 +0000 (10:02 +0530)]
sched: allow cpuacct stats to be reset

Currently the schedstats implementation does not allow the statistics
to be reset. This patch aims to allow that.

  echo 0 > cpuacct.usage

resets the usage. Any other value is not allowed and returns -EINVAL.

Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: cleanup cpuacct variable names
Dhaval Giani [Fri, 29 Feb 2008 04:32:43 +0000 (10:02 +0530)]
sched: cleanup cpuacct variable names

Change the variable names to the common convention for the cpuacct
subsystem.

Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agotasklets: execute tasklets in the same order they were queued
Olof Johansson [Tue, 4 Mar 2008 23:23:25 +0000 (15:23 -0800)]
tasklets: execute tasklets in the same order they were queued

I noticed this when looking at an openswan issue.  Openswan (ab?)uses the
tasklet API to defer processing of packets in some situations, with one
packet per tasklet_action().  I started noticing sequences of
backwards-ordered sequence numbers coming over the wire, since new tasklets
are always queued at the head of the list but processed sequentially.

Convert it to instead append new entries to the tail of the list.  As an
extra bonus, the splicing code in takeover_tasklets() no longer has to
iterate over the list.

Signed-off-by: Olof Johansson <olof@lixom.net>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: rt-group: smp balancing
Peter Zijlstra [Sat, 19 Apr 2008 17:44:58 +0000 (19:44 +0200)]
sched: rt-group: smp balancing

Currently the rt group scheduling does a per cpu runtime limit, however
the rt load balancer makes no guarantees about an equal spread of real-
time tasks, just that at any one time, the highest priority tasks run.

Solve this by making the runtime limit a global property by borrowing
excessive runtime from the other cpus once the local limit runs out.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: rt-group: synchonised bandwidth period
Peter Zijlstra [Sat, 19 Apr 2008 17:44:57 +0000 (19:44 +0200)]
sched: rt-group: synchonised bandwidth period

Various SMP balancing algorithms require that the bandwidth period
run in sync.

Possible improvements are moving the rt_bandwidth thing into root_domain
and keeping a span per rt_bandwidth which marks throttled cpus.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agotime: add ns_to_ktime()
Ingo Molnar [Wed, 27 Feb 2008 13:05:10 +0000 (14:05 +0100)]
time: add ns_to_ktime()

Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: fix regression with sched yield
Peter Zijlstra [Mon, 18 Feb 2008 12:39:37 +0000 (13:39 +0100)]
sched: fix regression with sched yield

Balbir Singh reported:

> 1:mon> t
> [c0000000e7677da0c000000000067de0 .sys_sched_yield+0x6c/0xbc
> [c0000000e7677e30c000000000008748 syscall_exit+0x0/0x40
> --- Exception: c01 (System Call) at 00000400001d09e4
> SP (4000664cb10) is in userspace
> 1:mon> r
> cpu 0x1: Vector: 300 (Data Access) at [c0000000e7677aa0]
>     pc: c000000000068e50: .yield_task_fair+0x94/0xc4
>     lr: c000000000067de0: .sys_sched_yield+0x6c/0xbc

the check that should have avoided that is:

        /*
         * Are we the only task in the tree?
         */
        if (unlikely(rq->load.weight == curr->se.load.weight))
                return;

But I guess that overlooks rt tasks, they also increase the load.
So I guess something like this ought to fix it..

Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agolatencytop: optimize LT_BACKTRACEDEPTH loops a bit
Dmitry Adamushko [Sun, 17 Feb 2008 21:34:07 +0000 (22:34 +0100)]
latencytop: optimize LT_BACKTRACEDEPTH loops a bit

There is no need to loop any longer when 'same == 0'.

Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: remove sysctl_sched_batch_wakeup_granularity
Ingo Molnar [Fri, 14 Mar 2008 15:09:59 +0000 (16:09 +0100)]
sched: remove sysctl_sched_batch_wakeup_granularity

it's unused.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: reenable sync wakeups
Ingo Molnar [Wed, 19 Mar 2008 00:37:10 +0000 (01:37 +0100)]
sched: reenable sync wakeups

Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: cache hot buddy
Ingo Molnar [Mon, 17 Mar 2008 08:36:53 +0000 (09:36 +0100)]
sched: cache hot buddy

Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: feat affine wakeups
Ingo Molnar [Wed, 19 Mar 2008 00:39:19 +0000 (01:39 +0100)]
sched: feat affine wakeups

Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: introduce SCHED_FEAT_SYNC_WAKEUPS, turn it off
Ingo Molnar [Sun, 16 Mar 2008 19:03:22 +0000 (20:03 +0100)]
sched: introduce SCHED_FEAT_SYNC_WAKEUPS, turn it off

turn off sync wakeups by default. They are not needed anymore - the
buddy logic should be smart enough to keep the system from
overscheduling.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: fix wakeup granularity for buddies
Peter Zijlstra [Sat, 19 Apr 2008 17:44:57 +0000 (19:44 +0200)]
sched: fix wakeup granularity for buddies

The wakeup buddy logic didn't use the same wakeup granularity logic as the
wakeup preemption did, this might cause the ->next buddy to be selected past
the point where we would have preempted had the task been a single running
instance.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: fix rq->clock overflows detection with CONFIG_NO_HZ
Guillaume Chazarain [Sat, 19 Apr 2008 17:44:57 +0000 (19:44 +0200)]
sched: fix rq->clock overflows detection with CONFIG_NO_HZ

When using CONFIG_NO_HZ, rq->tick_timestamp is not updated every TICK_NSEC.
We check that the number of skipped ticks matches the clock jump seen in
__update_rq_clock().

Signed-off-by: Guillaume Chazarain <guichaz@yahoo.fr>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: sched.c needs tick.h
Reynes Philippe [Mon, 17 Mar 2008 23:19:05 +0000 (16:19 -0700)]
sched: sched.c needs tick.h

kernel/sched.c:506: erreur: implicit declaration of function tick_get_tick_sched
kernel/sched.c:506: erreur: invalid type argument of ->
kernel/sched.c:506: erreur: NOHZ_MODE_INACTIVE undeclared (first use in this function)
kernel/sched.c:506: erreur: (Each undeclared identifier is reported only once
kernel/sched.c:506: erreur: for each function it appears in.)

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: make cpu_clock() globally synchronous
Ingo Molnar [Thu, 28 Feb 2008 20:00:21 +0000 (21:00 +0100)]
sched: make cpu_clock() globally synchronous

Alexey Zaytsev reported (and bisected) that the introduction of
cpu_clock() in printk made the timestamps jump back and forth.

Make cpu_clock() more reliable while still keeping it fast when it's
called frequently.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agosched: re-do "sched: fix fair sleepers"
Ingo Molnar [Mon, 14 Apr 2008 06:53:32 +0000 (08:53 +0200)]
sched: re-do "sched: fix fair sleepers"

re-apply:

| commit e22ecef1d2658ba54ed7d3fdb5d60829fb434c23
| Author: Ingo Molnar <mingo@elte.hu>
| Date:   Fri Mar 14 22:16:08 2008 +0100
|
|     sched: fix fair sleepers
|
|     Fair sleepers need to scale their latency target down by runqueue
|     weight. Otherwise busy systems will gain ever larger sleep bonus.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
16 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...
Linus Torvalds [Sat, 19 Apr 2008 01:18:30 +0000 (18:18 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  security: fix up documentation for security_module_enable
  Security: Introduce security= boot parameter
  Audit: Final renamings and cleanup
  SELinux: use new audit hooks, remove redundant exports
  Audit: internally use the new LSM audit hooks
  LSM/Audit: Introduce generic Audit LSM hooks
  SELinux: remove redundant exports
  Netlink: Use generic LSM hook
  Audit: use new LSM hooks instead of SELinux exports
  SELinux: setup new inode/ipc getsecid hooks
  LSM: Introduce inode_getsecid and ipc_getsecid hooks

16 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6.26
Linus Torvalds [Sat, 19 Apr 2008 01:02:35 +0000 (18:02 -0700)]
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6.26

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6.26: (1090 commits)
  [NET]: Fix and allocate less memory for ->priv'less netdevices
  [IPV6]: Fix dangling references on error in fib6_add().
  [NETLABEL]: Fix NULL deref in netlbl_unlabel_staticlist_gen() if ifindex not found
  [PKT_SCHED]: Fix datalen check in tcf_simp_init().
  [INET]: Uninline the __inet_inherit_port call.
  [INET]: Drop the inet_inherit_port() call.
  SCTP: Initialize partial_bytes_acked to 0, when all of the data is acked.
  [netdrvr] forcedeth: internal simplifications; changelog removal
  phylib: factor out get_phy_id from within get_phy_device
  PHY: add BCM5464 support to broadcom PHY driver
  cxgb3: Fix __must_check warning with dev_dbg.
  tc35815: Statistics cleanup
  natsemi: fix MMIO for PPC 44x platforms
  [TIPC]: Cleanup of TIPC reference table code
  [TIPC]: Optimized initialization of TIPC reference table
  [TIPC]: Remove inlining of reference table locking routines
  e1000: convert uint16_t style integers to u16
  ixgb: convert uint16_t style integers to u16
  sb1000.c: make const arrays static
  sb1000.c: stop inlining largish static functions
  ...

16 years agosecurity: fix up documentation for security_module_enable
James Morris [Fri, 7 Mar 2008 01:23:49 +0000 (12:23 +1100)]
security: fix up documentation for security_module_enable

security_module_enable() can only be called during kernel init.

Signed-off-by: James Morris <jmorris@namei.org>
16 years agoSecurity: Introduce security= boot parameter
Ahmed S. Darwish [Thu, 6 Mar 2008 16:09:10 +0000 (18:09 +0200)]
Security: Introduce security= boot parameter

Add the security= boot parameter. This is done to avoid LSM
registration clashes in case of more than one bult-in module.

User can choose a security module to enable at boot. If no
security= boot parameter is specified, only the first LSM
asking for registration will be loaded. An invalid security
module name will be treated as if no module has been chosen.

LSM modules must check now if they are allowed to register
by calling security_module_enable(ops) first. Modify SELinux
and SMACK to do so.

Do not let SMACK register smackfs if it was not chosen on
boot. Smackfs assumes that smack hooks are registered and
the initial task security setup (swapper->security) is done.

Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
16 years agoAudit: Final renamings and cleanup
Ahmed S. Darwish [Fri, 18 Apr 2008 23:59:43 +0000 (09:59 +1000)]
Audit: Final renamings and cleanup

Rename the se_str and se_rule audit fields elements to
lsm_str and lsm_rule to avoid confusion.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
16 years agoSELinux: use new audit hooks, remove redundant exports
Ahmed S. Darwish [Sat, 1 Mar 2008 20:03:14 +0000 (22:03 +0200)]
SELinux: use new audit hooks, remove redundant exports

Setup the new Audit LSM hooks for SELinux.
Remove the now redundant exported SELinux Audit interface.

Audit: Export 'audit_krule' and 'audit_field' to the public
since their internals are needed by the implementation of the
new LSM hook 'audit_rule_known'.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
16 years agoAudit: internally use the new LSM audit hooks
Ahmed S. Darwish [Sat, 1 Mar 2008 20:01:11 +0000 (22:01 +0200)]
Audit: internally use the new LSM audit hooks

Convert Audit to use the new LSM Audit hooks instead of
the exported SELinux interface.

Basically, use:
security_audit_rule_init
secuirty_audit_rule_free
security_audit_rule_known
security_audit_rule_match

instad of (respectively) :
selinux_audit_rule_init
selinux_audit_rule_free
audit_rule_has_selinux
selinux_audit_rule_match

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
16 years agoLSM/Audit: Introduce generic Audit LSM hooks
Ahmed S. Darwish [Sat, 1 Mar 2008 20:00:05 +0000 (22:00 +0200)]
LSM/Audit: Introduce generic Audit LSM hooks

Introduce a generic Audit interface for security modules
by adding the following new LSM hooks:

audit_rule_init(field, op, rulestr, lsmrule)
audit_rule_known(krule)
audit_rule_match(secid, field, op, rule, actx)
audit_rule_free(rule)

Those hooks are only available if CONFIG_AUDIT is enabled.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Reviewed-by: Paul Moore <paul.moore@hp.com>
16 years agoSELinux: remove redundant exports
Ahmed S. Darwish [Sat, 1 Mar 2008 19:58:32 +0000 (21:58 +0200)]
SELinux: remove redundant exports

Remove the following exported SELinux interfaces:
selinux_get_inode_sid(inode, sid)
selinux_get_ipc_sid(ipcp, sid)
selinux_get_task_sid(tsk, sid)
selinux_sid_to_string(sid, ctx, len)

They can be substitued with the following generic equivalents
respectively:
new LSM hook, inode_getsecid(inode, secid)
new LSM hook, ipc_getsecid*(ipcp, secid)
LSM hook, task_getsecid(tsk, secid)
LSM hook, sid_to_secctx(sid, ctx, len)

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Reviewed-by: Paul Moore <paul.moore@hp.com>
16 years agoNetlink: Use generic LSM hook
Ahmed S. Darwish [Sat, 1 Mar 2008 19:56:22 +0000 (21:56 +0200)]
Netlink: Use generic LSM hook

Don't use SELinux exported selinux_get_task_sid symbol.
Use the generic LSM equivalent instead.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Paul Moore <paul.moore@hp.com>
16 years agoAudit: use new LSM hooks instead of SELinux exports
Ahmed S. Darwish [Sat, 1 Mar 2008 19:54:38 +0000 (21:54 +0200)]
Audit: use new LSM hooks instead of SELinux exports

Stop using the following exported SELinux interfaces:
selinux_get_inode_sid(inode, sid)
selinux_get_ipc_sid(ipcp, sid)
selinux_get_task_sid(tsk, sid)
selinux_sid_to_string(sid, ctx, len)
kfree(ctx)

and use following generic LSM equivalents respectively:
security_inode_getsecid(inode, secid)
security_ipc_getsecid*(ipcp, secid)
security_task_getsecid(tsk, secid)
security_sid_to_secctx(sid, ctx, len)
security_release_secctx(ctx, len)

Call security_release_secctx only if security_secid_to_secctx
succeeded.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Reviewed-by: Paul Moore <paul.moore@hp.com>
16 years agoSELinux: setup new inode/ipc getsecid hooks
Ahmed S. Darwish [Sat, 1 Mar 2008 19:52:30 +0000 (21:52 +0200)]
SELinux: setup new inode/ipc getsecid hooks

Setup the new inode_getsecid and ipc_getsecid() LSM hooks
for SELinux.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Reviewed-by: Paul Moore <paul.moore@hp.com>
16 years agoLSM: Introduce inode_getsecid and ipc_getsecid hooks
Ahmed S. Darwish [Sat, 1 Mar 2008 19:51:09 +0000 (21:51 +0200)]
LSM: Introduce inode_getsecid and ipc_getsecid hooks

Introduce inode_getsecid(inode, secid) and ipc_getsecid(ipcp, secid)
LSM hooks. These hooks will be used instead of similar exported
SELinux interfaces.

Let {inode,ipc,task}_getsecid hooks set the secid to 0 by default
if CONFIG_SECURITY is not defined or if the hook is set to
NULL (dummy). This is done to notify the caller that no valid
secid exists.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
Reviewed-by: Paul Moore <paul.moore@hp.com>
16 years ago[NET]: Fix and allocate less memory for ->priv'less netdevices
Alexey Dobriyan [Fri, 18 Apr 2008 22:43:32 +0000 (15:43 -0700)]
[NET]: Fix and allocate less memory for ->priv'less netdevices

This patch effectively reverts commit d0498d9ae1a5cebac363e38907266d5cd2eedf89
aka "[NET]: Do not allocate unneeded memory for dev->priv alignment."
It was found to be buggy because of final unconditional += NETDEV_ALIGN_CONST
removal.

For example, for sizeof(struct net_device) being 2048 bytes, "alloc_size"
was also 2048 bytes, but allocator with debugging options turned on started
giving out !32-byte aligned memory resulting in redzones overwrites.

Patch does small optimization in ->priv'less case: bumping size to next
32-byte boundary was always done to ensure ->priv will also be aligned.
But, no ->priv, no need to do that.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
16 years agox86 PAT: fix mmap() of holes
Ingo Molnar [Fri, 18 Apr 2008 19:32:22 +0000 (21:32 +0200)]
x86 PAT: fix mmap() of holes

do not return a -EINVAL when mmap()-ing PCI holes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
16 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
Linus Torvalds [Fri, 18 Apr 2008 18:25:31 +0000 (11:25 -0700)]
Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (137 commits)
  [SCSI] iscsi: bidi support for iscsi_tcp
  [SCSI] iscsi: bidi support at the generic libiscsi level
  [SCSI] iscsi: extended cdb support
  [SCSI] zfcp: Fix error handling for blocked unit for send FCP command
  [SCSI] zfcp: Remove zfcp_erp_wait from slave destory handler to fix deadlock
  [SCSI] zfcp: fix 31 bit compile warnings
  [SCSI] bsg: no need to set BSG_F_BLOCK bit in bsg_complete_all_commands
  [SCSI] bsg: remove minor in struct bsg_device
  [SCSI] bsg: use better helper list functions
  [SCSI] bsg: replace kobject_get with blk_get_queue
  [SCSI] bsg: takes a ref to struct device in fops->open
  [SCSI] qla1280: remove version check
  [SCSI] libsas: fix endianness bug in sas_ata
  [SCSI] zfcp: fix compiler warning caused by poking inside new semaphore (linux-next)
  [SCSI] aacraid: Do not describe check_reset parameter with its value
  [SCSI] aacraid: Fix down_interruptible() to check the return value
  [SCSI] sun3_scsi_vme: add MODULE_LICENSE
  [SCSI] st: rename flush_write_buffer()
  [SCSI] tgt: use KMEM_CACHE macro
  [SCSI] initio: fix big endian problems for auto request sense
  ...

16 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394...
Linus Torvalds [Fri, 18 Apr 2008 18:24:29 +0000 (11:24 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6: (43 commits)
  firewire: cleanups
  firewire: fix synchronization of gap counts
  firewire: wait until PHY configuration packet was transmitted (fix bus reset loop)
  firewire: remove unused struct member
  firewire: use bitwise and to get reg in handle_registers
  firewire: replace more hex values with defined csr constants
  firewire: reread config ROM when device reset the bus
  firewire: replace static ROM cache by allocated cache
  firewire: fw-ohci: work around generation bug in TI controllers (fix AV/C and more)
  firewire: fw-ohci: extend logging of bus generations and node ID
  firewire: fw-ohci: conditionally log busReset interrupts
  firewire: fw-ohci: don't append to AT context when it's not active
  firewire: fw-ohci: log regAccessFail events
  firewire: fw-ohci: make sure HCControl register LPS bit is set
  firewire: fw-ohci: missing PPC PMac feature calls in failure path
  firewire: fw-ohci: untangle a mixed unsigned/signed expression
  firewire: debug interrupt events
  firewire: fw-ohci: catch self_id_count == 0
  firewire: fw-ohci: add self ID error check
  firewire: fw-ohci: refactor probe, remove, suspend, resume
  ...

16 years agolibata: fix boot panic with SATAPI devices on non-SFF HBAs
James Bottomley [Fri, 18 Apr 2008 18:18:48 +0000 (13:18 -0500)]
libata: fix boot panic with SATAPI devices on non-SFF HBAs

The kernel now panics reliably on boot if you have a SATAPI device
connected.

The problem was introduced by the libata merge trying to pull out all
the SFF code into a separate module.  Unfortunately, if you're a satapi
device you usually need to call atapi_request_sense, which has a bare
invocation of a SFF callback which is NULL on non-SFF HBAs.  Fix this by
making the call conditional.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
16 years agoMerge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfashe...
Linus Torvalds [Fri, 18 Apr 2008 17:15:22 +0000 (10:15 -0700)]
Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2: (64 commits)
  ocfs2/net: Add debug interface to o2net
  ocfs2: Only build ocfs2/dlm with the o2cb stack module
  ocfs2/cluster: Get rid of arguments to the timeout routines
  ocfs2: Put tree in MAINTAINERS
  ocfs2: Use BUG_ON
  ocfs2: Convert ocfs2 over to unlocked_ioctl
  ocfs2: Improve rename locking
  fs/ocfs2/aops.c: test for IS_ERR rather than 0
  ocfs2: Add inode stealing for ocfs2_reserve_new_inode
  ocfs2: Add ac_alloc_slot in ocfs2_alloc_context
  ocfs2: Add a new parameter for ocfs2_reserve_suballoc_bits
  ocfs2: Enable cross extent block merge.
  ocfs2: Add support for cross extent block
  ocfs2: Move /sys/o2cb to /sys/fs/o2cb
  sysfs: Allow removal of symlinks in the sysfs root
  ocfs2:  Reconnect after idle time out.
  ocfs2/dlm: Cleanup lockres print
  ocfs2/dlm: Fix lockname in lockres print function
  ocfs2/dlm: Move dlm_print_one_mle() from dlmmaster.c to dlmdebug.c
  ocfs2/dlm: Dumps the purgelist into a debugfs file
  ...

16 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw
Linus Torvalds [Fri, 18 Apr 2008 17:02:46 +0000 (10:02 -0700)]
Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw: (49 commits)
  [GFS2] fix assertion in log_refund()
  [GFS2] fix GFP_KERNEL misuses
  [GFS2] test for IS_ERR rather than 0
  [GFS2] Invalidate cache at correct point
  [GFS2] fs/gfs2/recovery.c: suppress warnings
  [GFS2] Faster gfs2_bitfit algorithm
  [GFS2] Streamline quota lock/check for no-quota case
  [GFS2] Remove drop of module ref where not needed
  [GFS2] gfs2_adjust_quota has broken unstuffing code
  [GFS2] possible null pointer dereference fixup
  [GFS2] Need to ensure that sector_t is 64bits for GFS2
  [GFS2] re-support special inode
  [GFS2] remove gfs2_dev_iops
  [GFS2] fix file_system_type leak on gfs2meta mount
  [GFS2] Allow bmap to allocate extents
  [GFS2] Fix a page lock / glock deadlock
  [GFS2] proper extern for gfs2/locking/dlm/mount.c:gdlm_ops
  [GFS2] gfs2/ops_file.c should #include "ops_inode.h"
  [GFS2] be*_add_cpu conversion
  [GFS2] Fix bug where we called drop_bh incorrectly
  ...

16 years agox86: kgdb build fix
Harvey Harrison [Fri, 18 Apr 2008 16:54:38 +0000 (09:54 -0700)]
x86: kgdb build fix

TF_MASK is no longer defined, use X86_EFLAGS_TF.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
16 years ago[SCSI] iscsi: bidi support for iscsi_tcp
Boaz Harrosh [Fri, 18 Apr 2008 15:11:53 +0000 (10:11 -0500)]
[SCSI] iscsi: bidi support for iscsi_tcp

access the right scsi_in() and/or scsi_out() side of things.
also for resid

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Reviewed-by: Pete Wyckoff <pw@osc.edu>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
16 years ago[SCSI] iscsi: bidi support at the generic libiscsi level
Boaz Harrosh [Fri, 18 Apr 2008 15:11:52 +0000 (10:11 -0500)]
[SCSI] iscsi: bidi support at the generic libiscsi level

- prepare the additional bidi_read rlength header.
- access the right scsi_in() and/or scsi_out() side of things.
  also for resid.
- Handle BIDI underflow overflow from target

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Reviewed-by: Pete Wyckoff <pw@osc.edu>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
16 years ago[SCSI] iscsi: extended cdb support
Boaz Harrosh [Fri, 18 Apr 2008 15:11:51 +0000 (10:11 -0500)]
[SCSI] iscsi: extended cdb support

Support for extended CDBs in iscsi.
All we need is to check if command spills over 16 bytes then allocate
an iscsi-extended-header for the leftovers.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Reviewed-by: Pete Wyckoff <pw@osc.edu>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
16 years ago[SCSI] zfcp: Fix error handling for blocked unit for send FCP command
Christof Schmitt [Fri, 18 Apr 2008 10:51:57 +0000 (12:51 +0200)]
[SCSI] zfcp: Fix error handling for blocked unit for send FCP command

In the case the unit is blocked, zfcp_unit_get has not been called
yet, so the error handling path should not call zfcp_unit_put.

Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
16 years ago[SCSI] zfcp: Remove zfcp_erp_wait from slave destory handler to fix deadlock
Christof Schmitt [Fri, 18 Apr 2008 10:51:56 +0000 (12:51 +0200)]
[SCSI] zfcp: Remove zfcp_erp_wait from slave destory handler to fix deadlock

The testcase
# chchp -v 0 0.da && sleep 59 && chchp -v 1 0.da
results in this deadlock situation:

STACK TRACE FOR TASK: 0x7e9a2048 (zfcperp0.0.c613)
0 schedule+816 [0x356b3c]
1 schedule_timeout+172 [0x357340]
2 wait_for_common+192 [0x3565fc]
3 flush_cpu_workqueue+116 [0x52af0]
4 flush_workqueue+116 [0x533b8]
5 fc_remote_port_add+64 [0x1c83ec]
6 zfcp_erp_thread+4534 [0x26585a]
7 kernel_thread_starter+6 [0x195d2]

STACK TRACE FOR TASK: 0x7f8ec048 (fc_wq_0)
0 schedule+816 [0x356b3c]
1 zfcp_erp_wait+104 [0x264568]
2 zfcp_scsi_slave_destroy+64 [0x261b24]
3 __scsi_remove_device+154 [0x1c24ba]
4 scsi_remove_device+62 [0x1c2512]
5 __scsi_remove_target+198 [0x1c25ea]
6 __remove_child+58 [0x1c26d6]
7 device_for_each_child+66 [0x1ab566]
8 scsi_remove_target+98 [0x1c268a]
9 run_workqueue+200 [0x5272c]
10 worker_thread+146 [0x52882]
11 kthread+140 [0x58360]
12 kernel_thread_starter+6 [0x195d2]

Remove the zfcp_erp_wait call that is not required here to prevent the
deadlock situation.

Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
16 years ago[SCSI] zfcp: fix 31 bit compile warnings
Martin Peschke [Fri, 18 Apr 2008 10:51:55 +0000 (12:51 +0200)]
[SCSI] zfcp: fix 31 bit compile warnings

drivers/s390/scsi/zfcp_aux.c: In function ‘zfcp_fsf_incoming_els_rscn’:
drivers/s390/scsi/zfcp_aux.c:1379: warning: cast from pointer to integer of
different size
drivers/s390/scsi/zfcp_aux.c: In function ‘zfcp_fsf_incoming_els_plogi’:
drivers/s390/scsi/zfcp_aux.c:1432: warning: cast from pointer to integer of
different size
drivers/s390/scsi/zfcp_aux.c: In function ‘zfcp_fsf_incoming_els_logo’:
drivers/s390/scsi/zfcp_aux.c:1457: warning: cast from pointer to integer of
different size
..

Just passing pointers rids us of these warnings and improves readability.

Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
16 years ago[SCSI] bsg: no need to set BSG_F_BLOCK bit in bsg_complete_all_commands
FUJITA Tomonori [Mon, 31 Mar 2008 01:03:42 +0000 (10:03 +0900)]
[SCSI] bsg: no need to set BSG_F_BLOCK bit in bsg_complete_all_commands

Before bsg_complete_all_commands is called, BSG_F_BLOCK bit is always
set.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
16 years ago[SCSI] bsg: remove minor in struct bsg_device
FUJITA Tomonori [Mon, 31 Mar 2008 01:03:41 +0000 (10:03 +0900)]
[SCSI] bsg: remove minor in struct bsg_device

minor in struct bsg_device is used as identifier to find the
corresponding struct bsg_device_class. However, request_queuse can be
used as identifier for that and the minor in struct bsg_device is
unnecessary.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
16 years ago[SCSI] bsg: use better helper list functions
FUJITA Tomonori [Mon, 31 Mar 2008 01:03:40 +0000 (10:03 +0900)]
[SCSI] bsg: use better helper list functions

This replace hlist_for_each and list_entry with hlist_for_each_entry
and list_first_entry respectively.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
16 years ago[SCSI] bsg: replace kobject_get with blk_get_queue
FUJITA Tomonori [Mon, 31 Mar 2008 01:03:39 +0000 (10:03 +0900)]
[SCSI] bsg: replace kobject_get with blk_get_queue

Both takes a ref to a queue. But blk_get_queue checks QUEUE_FLAG_DEAD
and is more appropriate interface here.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
16 years ago[SCSI] bsg: takes a ref to struct device in fops->open
FUJITA Tomonori [Mon, 31 Mar 2008 01:03:38 +0000 (10:03 +0900)]
[SCSI] bsg: takes a ref to struct device in fops->open

bsg_register_queue() takes a ref to struct device that a caller
passes. For example, bsg takes a ref to the sdev_gendev for scsi
devices. However, bsg doesn't inrease the refcount in fops->open. So
while an application opens a bsg device, the scsi device that the bsg
device holds can go away (bsg also takes a ref to a queue, but it
doesn't prevent the device from going away).

With this patch, bsg increases the refcount of struct device in
fops->open and decreases it in fops->release.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
16 years agoMerge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
Linus Torvalds [Fri, 18 Apr 2008 16:44:55 +0000 (09:44 -0700)]
Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6: (27 commits)
  [IA64] kdump: Add crash_save_vmcoreinfo for INIT
  [IA64] Fix NUMA configuration issue
  [IA64] Itanium Spec updates
  [IA64] Untangle sync_icache_dcache() page size determination
  [IA64] arch/ia64/kernel/: use time_* macros
  [IA64] remove redundant display of free swap space in show_mem()
  [IA64] make IOMMU respect the segment boundary limits
  [IA64] kprobes: kprobe-booster for ia64
  [IA64] fix getpid and set_tid_address fast system calls for pid namespaces
  [IA64] Replace explicit jiffies tests with time_* macros.
  [IA64] use goto to jump out do/while_each_thread
  [IA64] Fix unlock ordering in smp_callin
  [IA64] pgd_offset() constfication.
  [IA64] kdump: crash.c coding style fix
  [IA64] kdump: add kdump_on_fatal_mca
  [IA64] Minimize per_cpu reservations.
  [IA64] Correct pernodesize calculation.
  [IA64] Kernel parameter for max number of concurrent global TLB purges
  [IA64] Multiple outstanding ptc.g instruction support
  [IA64] Implement smp_call_function_mask for ia64
  ...

16 years agoocfs2/net: Add debug interface to o2net
Sunil Mushran [Mon, 14 Apr 2008 17:46:19 +0000 (10:46 -0700)]
ocfs2/net: Add debug interface to o2net

This patch exposes o2net information via debugfs. The information includes
the list of sockets (sock_containers) as well as the list of outstanding
messages (send_tracking). Useful for o2dlm debugging.

(This patch is derived from an earlier one written by Zach Brown that
exposed the same information via /proc.)

[Mark: checkpatch fixes]

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Reviewed-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agoocfs2: Only build ocfs2/dlm with the o2cb stack module
Mark Fasheh [Fri, 4 Apr 2008 19:45:55 +0000 (12:45 -0700)]
ocfs2: Only build ocfs2/dlm with the o2cb stack module

fs/ocfs2/dlm/ocfs2_dlm.ko and fs/ocfs2/dlm/ocfs2_dlmfs.ko get built if
CONFIG_FS_OCFS2 is specified. This isn't quite how it should happen any more
- the "o2cb" dlm modules should only be built if CONFIG_FS_OCFS2_O2CB is
set, so update the dlm Makefile accordingly.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
16 years agoocfs2/cluster: Get rid of arguments to the timeout routines
Jeff Mahoney [Fri, 28 Mar 2008 23:44:13 +0000 (16:44 -0700)]
ocfs2/cluster: Get rid of arguments to the timeout routines

We keep seeing bug reports related to NULL pointer derefs in
o2net_set_nn_state(). When I originally wrote up the configurable timeout
patch, I had tried to plan for multiple clusters. This was silly.

The timeout routines all use o2nm_single_cluster so there's no point in
passing an argument at all. This patch removes the arguments and kills those
bugs dead.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agoocfs2: Put tree in MAINTAINERS
Joel Becker [Sun, 23 Mar 2008 05:08:07 +0000 (22:08 -0700)]
ocfs2: Put tree in MAINTAINERS

The ocfs2 MAINTAINERS entry should have the git tree URL.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agoocfs2: Use BUG_ON
Julia Lawall [Tue, 4 Mar 2008 23:21:05 +0000 (15:21 -0800)]
ocfs2: Use BUG_ON

if (...) BUG(); should be replaced with BUG_ON(...) when the test has no
side-effects to allow a definition of BUG_ON that drops the code completely.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@ disable unlikely @ expression E,f; @@

(
  if (<... f(...) ...>) { BUG(); }
|
- if (unlikely(E)) { BUG(); }
+ BUG_ON(E);
)

@@ expression E,f; @@

(
  if (<... f(...) ...>) { BUG(); }
|
- if (E) { BUG(); }
+ BUG_ON(E);
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agoocfs2: Convert ocfs2 over to unlocked_ioctl
Andi Kleen [Sun, 27 Jan 2008 02:17:17 +0000 (03:17 +0100)]
ocfs2: Convert ocfs2 over to unlocked_ioctl

As far as I can see there is nothing in ocfs2_ioctl that requires the BKL,
so use unlocked_ioctl

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agoocfs2: Improve rename locking
Jan Kara [Thu, 21 Feb 2008 17:00:00 +0000 (18:00 +0100)]
ocfs2: Improve rename locking

ocfs2_rename() was being too aggressive with the rename lock - we only need
it for certain forms of directory rename.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agofs/ocfs2/aops.c: test for IS_ERR rather than 0
Julia Lawall [Fri, 28 Mar 2008 21:43:10 +0000 (14:43 -0700)]
fs/ocfs2/aops.c: test for IS_ERR rather than 0

The function ocfs2_start_trans always returns either a valid pointer or a
value made with ERR_PTR, so its result should be tested with IS_ERR, not
with a test for 0.

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agoocfs2: Add inode stealing for ocfs2_reserve_new_inode
Tao Ma [Wed, 5 Mar 2008 08:11:46 +0000 (16:11 +0800)]
ocfs2: Add inode stealing for ocfs2_reserve_new_inode

Inode allocation is modified to look in other nodes allocators during
extreme out of space situations. We retry our own slot when space is freed
back to the global bitmap, or whenever we've allocated more than 1024 inodes
from another slot.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agoocfs2: Add ac_alloc_slot in ocfs2_alloc_context
Tao Ma [Mon, 3 Mar 2008 09:12:30 +0000 (17:12 +0800)]
ocfs2: Add ac_alloc_slot in ocfs2_alloc_context

In inode stealing, we no longer restrict the allocation to
happen in the local node. So it is neccessary for us to add
a new member in ocfs2_alloc_context to indicate which slot
we are using for allocation. We also modify the process of
local alloc so that this member can be used there also.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agoocfs2: Add a new parameter for ocfs2_reserve_suballoc_bits
Tao Ma [Mon, 3 Mar 2008 09:12:09 +0000 (17:12 +0800)]
ocfs2: Add a new parameter for ocfs2_reserve_suballoc_bits

In some cases(Inode stealing from other nodes), we may not want
ocfs2_reserve_suballoc_bits to allocate new groups from the
global_bitmap since it may already be full. So add a new parameter
for this.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agoocfs2: Enable cross extent block merge.
Tao Ma [Wed, 30 Jan 2008 06:21:32 +0000 (14:21 +0800)]
ocfs2: Enable cross extent block merge.

In ocfs2_figure_merge_contig_type, we judge whether there exists
a cross extent block merge and enable it by setting CONTIG_LEFT
and CONTIG_RIGHT accordingly.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agoocfs2: Add support for cross extent block
Tao Ma [Wed, 30 Jan 2008 06:21:05 +0000 (14:21 +0800)]
ocfs2: Add support for cross extent block

In ocfs2_merge_rec_left, when we find the merge extent is "CONTIG_RIGHT"
with the first extent record of the next extent block, we will merge it to
the next extent block and change all the related extent blocks accordingly.

In ocfs2_merge_rec_right, when we find the merge extent is "CONTIG_LEFT"
with the last extent record of the previous extent block, we will merge
it to the prevoius extent block and change all the related extent blocks
accordingly.

As for CONTIG_LEFTRIGHT, we will handle CONTIG_RIGHT first so that when
the index is zero, the merge process will be more efficient and easier.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agoocfs2: Move /sys/o2cb to /sys/fs/o2cb
Mark Fasheh [Wed, 30 Jan 2008 01:08:26 +0000 (17:08 -0800)]
ocfs2: Move /sys/o2cb to /sys/fs/o2cb

/sys/fs is where we really want file system specific sysfs objects.

Ocfs2-tools has been updated to look in /sys/fs/o2cb. We can maintain
backwards compatibility with old ocfs2-tools by using a sysfs symlink. After
some time (2 years), the symlink can be safely removed. This patch also adds
documentation to make it easier for people to figure out what /sys/fs/o2cb
is used for.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
16 years agosysfs: Allow removal of symlinks in the sysfs root
Mark Fasheh [Tue, 29 Jan 2008 22:35:18 +0000 (14:35 -0800)]
sysfs: Allow removal of symlinks in the sysfs root

Allow callers of sysfs_remove_link() to pass a NULL kobj, in which case
sysfs_root will be used as the parent directory. This allows us to tear down
top level symlinks created via sysfs_create_link(), which already has
similar handling of a NULL parent object.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
16 years agoocfs2: Reconnect after idle time out.
Tao Ma [Wed, 5 Mar 2008 07:50:12 +0000 (15:50 +0800)]
ocfs2:  Reconnect after idle time out.

Currently, o2net connects to a node on hb_up and disconnects on
hb_down and net timeout.

It disconnects on net timeout is ok, but it should attempt to
reconnect back. This is because sometimes nodes get overloaded
enough that the network connection breaks but the disk hb does not.
And if we get into that situation, we either fence (unnecessarily)
or wait for its disk hb to die (and sometimes hang in the process).

So in this updated scheme, when the network disconnects, we keep
attempting to reconnect till we succeed or we get a disk hb down
event.

If the other node is really dead, then we will eventually get a
node down event. If not, we should be able to connect again and
continue.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>