[PULL] cpumask offstack finalization

From: Rusty Russell
Date: Wed Feb 09 2011 - 00:39:31 EST

Hi Ingo,

A few more obsolete uses of cpumask has crept into the tree; all easily
fixed. This is rebased onto your -tip tree and re-tested; it finally means
that we can detect obsolescent (and hence dangerous) cpumask usage when
CONFIG_CPUMASK_OFFSTACK=y. It finally reduces the actual allocation of
cpumask_var_t to the number of cpus we actually have.

I assume you want these via your tree: they definitely need testing across
architectures, though the transforms are mechanical.

Thanks!
Rusty.

The following changes since commit 25ca954821a28c2648feeb166bcea0488ee0c202:

Merge branch 'core/urgent' (2011-02-08 16:18:50 +0100)

are available in the git repository at:

ssh://master.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-x86.git cpumask

Rusty Russell (9):
cpumask: remove obsolete cpu operation in x86/kernel/apb_timer.c
cpumask: update obsolescent use of cpumask_t in include/linux/interrupt.h
cpumask: update obsolescent use of cpu_isset in net/core/net-sysfs.c
cpumask: update obsolescent use of cpumask_t in drivers/crypto/n2_core.c
cpumask: truncate mm_struct.cpu_vm_mask for CONFIG_CPUMASK_OFFSTACK
cpumask: make task_struct.cpus_allowed a cpumask_var_t
cpumask: select disabling obsolete cpumask functions on x86
cpumask: remove struct cpumask definition when CONFIG_CPUMASK_OFFSTACK=y
cpumask: reduce cpumask_size

arch/arm/mach-integrator/cpu.c | 4 ++--
arch/blackfin/kernel/process.c | 3 ++-
arch/ia64/kernel/cpufreq/acpi-cpufreq.c | 4 ++--
arch/ia64/kernel/mca.c | 2 +-
arch/ia64/kernel/salinfo.c | 2 +-
arch/ia64/kernel/topology.c | 2 +-
arch/ia64/sn/kernel/sn2/sn_hwperf.c | 2 +-
arch/mips/include/asm/system.h | 3 ++-
arch/mips/kernel/cpufreq/loongson2_cpufreq.c | 2 +-
arch/mips/kernel/traps.c | 8 ++++----
arch/powerpc/kernel/smp.c | 2 +-
arch/powerpc/platforms/cell/spufs/sched.c | 2 +-
arch/sh/kernel/cpufreq.c | 2 +-
arch/sparc/kernel/sysfs.c | 2 +-
arch/sparc/kernel/us2e_cpufreq.c | 4 ++--
arch/sparc/kernel/us3_cpufreq.c | 4 ++--
arch/x86/kernel/apb_timer.c | 2 +-
arch/x86/kernel/cpu/mcheck/mce_intel.c | 2 +-
arch/x86/kernel/tboot.c | 2 +-
drivers/acpi/processor_throttling.c | 4 ++--
drivers/crypto/n2_core.c | 6 +++---
drivers/firmware/dcdbas.c | 2 +-
drivers/infiniband/hw/ipath/ipath_file_ops.c | 6 +++---
drivers/infiniband/hw/qib/qib_file_ops.c | 6 +++---
fs/proc/array.c | 4 ++--
include/linux/cpumask.h | 25 +++++++++++++++++++------
include/linux/cpuset.h | 2 +-
include/linux/init_task.h | 9 ++++++++-
include/linux/interrupt.h | 3 ++-
include/linux/mm_types.h | 21 ++++++++++++++++++---
include/linux/sched.h | 6 +++---
kernel/cpuset.c | 8 ++++----
kernel/fork.c | 23 +++++++++++++++++++----
kernel/kthread.c | 2 +-
kernel/sched.c | 18 +++++++++---------
kernel/sched_cpupri.c | 4 ++--
kernel/sched_fair.c | 12 ++++++------
kernel/sched_rt.c | 6 +++---
kernel/trace/trace_workqueue.c | 6 +++---
kernel/workqueue.c | 2 +-
lib/Kconfig | 8 ++++++--
lib/cpumask.c | 2 ++
lib/smp_processor_id.c | 2 +-
mm/init-mm.c | 2 +-
net/core/net-sysfs.c | 2 +-
45 files changed, 152 insertions(+), 93 deletions(-)

commit 248c3f52bec0473e5cc1be1c0888dc1a071e8019
Author: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Date: Wed Feb 9 11:59:52 2011 +1030

cpumask: remove obsolete cpu operation in x86/kernel/apb_timer.c

first_cpu -> cpumask_first

Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>

arch/x86/kernel/apb_timer.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

commit 0574017fe487e189512a4a295671f3f2ec492443
Author: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Date: Wed Feb 9 15:49:05 2011 +1030

cpumask: update obsolescent use of cpumask_t in include/linux/interrupt.h

Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>

include/linux/interrupt.h | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

commit d1314fe9407523fc4f0a943612e7c1bb50c2fb8d
Author: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Date: Wed Feb 9 15:49:35 2011 +1030

cpumask: update obsolescent use of cpu_isset in net/core/net-sysfs.c

Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>

net/core/net-sysfs.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

commit a35b7541e121159caabe962bbe6f01488cef5485
Author: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Date: Wed Feb 9 15:50:40 2011 +1030

cpumask: update obsolescent use of cpumask_t in drivers/crypto/n2_core.c

These days we use struct cpumask, and cpumask_* instead of the obsolescent
cpu_*/cpus_* functions.

Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>

drivers/crypto/n2_core.c | 6 +++---
1 files changed, 3 insertions(+), 3 deletions(-)

commit baece92fc28acf8e2e44dc6e942c656df12150c9
Author: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Date: Wed Feb 9 11:59:51 2011 +1030

cpumask: truncate mm_struct.cpu_vm_mask for CONFIG_CPUMASK_OFFSTACK

Turns cpu_vm_mask into a bitmap, and truncate it to cpumask_size(): if
CONFIG_CPUMASK_OFFSTACK is set, this will reflect nr_cpu_ids not NR_CPUS.

I do this rather than the classic [0] dangling array trick, because of
init_mm, which is static and widely referenced.

Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: anton@xxxxxxxxx
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Mike Travis <travis@xxxxxxx>

arch/x86/kernel/tboot.c | 2 +-
include/linux/mm_types.h | 21 ++++++++++++++++++---
kernel/fork.c | 6 +++---
mm/init-mm.c | 2 +-
4 files changed, 23 insertions(+), 8 deletions(-)

commit ae0849f28dba2ca41ca8d6631f5dcf9a81875eea
Author: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Date: Wed Feb 9 13:32:37 2011 +1030

cpumask: make task_struct.cpus_allowed a cpumask_var_t

This turns it into a pointer for everyone. Rather than churn everyone
via the tsk_cpus_allowed() wrapper, we change them directly. If there
are any users in the meantime they can use the wrapper.

For CONFIG_CPUMASK_OFFSTACK=y, we now allocate it off the end; it
would be better to avoid the indirection and use a dangling bitmap,
but I didn't want to alter the layout of task_struct and risk breaking
carefully balanced caches.

Even better would be to point to the fixed "one cpu" and "all cpus"
masks where possible, and make a copy when setting it to something
else. But you'd have to track down those naughty places which frob it
directly...

Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: anton@xxxxxxxxx
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Mike Travis <travis@xxxxxxx>

arch/arm/mach-integrator/cpu.c | 4 ++--
arch/blackfin/kernel/process.c | 3 ++-
arch/ia64/kernel/cpufreq/acpi-cpufreq.c | 4 ++--
arch/ia64/kernel/mca.c | 2 +-
arch/ia64/kernel/salinfo.c | 2 +-
arch/ia64/kernel/topology.c | 2 +-
arch/ia64/sn/kernel/sn2/sn_hwperf.c | 2 +-
arch/mips/include/asm/system.h | 3 ++-
arch/mips/kernel/cpufreq/loongson2_cpufreq.c | 2 +-
arch/mips/kernel/traps.c | 8 ++++----
arch/powerpc/kernel/smp.c | 2 +-
arch/powerpc/platforms/cell/spufs/sched.c | 2 +-
arch/sh/kernel/cpufreq.c | 2 +-
arch/sparc/kernel/sysfs.c | 2 +-
arch/sparc/kernel/us2e_cpufreq.c | 4 ++--
arch/sparc/kernel/us3_cpufreq.c | 4 ++--
arch/x86/kernel/cpu/mcheck/mce_intel.c | 2 +-
drivers/acpi/processor_throttling.c | 4 ++--
drivers/firmware/dcdbas.c | 2 +-
drivers/infiniband/hw/ipath/ipath_file_ops.c | 6 +++---
drivers/infiniband/hw/qib/qib_file_ops.c | 6 +++---
fs/proc/array.c | 4 ++--
include/linux/cpuset.h | 2 +-
include/linux/init_task.h | 9 ++++++++-
include/linux/sched.h | 4 ++--
kernel/cpuset.c | 8 ++++----
kernel/fork.c | 17 ++++++++++++++++-
kernel/kthread.c | 2 +-
kernel/sched.c | 18 +++++++++---------
kernel/sched_cpupri.c | 4 ++--
kernel/sched_fair.c | 12 ++++++------
kernel/sched_rt.c | 6 +++---
kernel/trace/trace_workqueue.c | 6 +++---
kernel/workqueue.c | 2 +-
lib/smp_processor_id.c | 2 +-
35 files changed, 94 insertions(+), 70 deletions(-)

commit 1602bf3ac37e66f5ad7022de4dcde317db964e32
Author: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Date: Wed Feb 9 11:59:49 2011 +1030

cpumask: select disabling obsolete cpumask functions on x86

It currently depends on CONFIG_BROKEN; change to be set by
CONFIG_CPUMASK_OFFSTACK now it all compiles.

We also complete it: the header shouldn't refer to the deprected
CPU_MASK_LAST_WORD, and the deprecated implementations are removed.

Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: anton@xxxxxxxxx
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Mike Travis <travis@xxxxxxx>

include/linux/cpumask.h | 4 ++--
include/linux/sched.h | 2 +-
lib/Kconfig | 8 ++++++--
lib/cpumask.c | 2 ++
4 files changed, 11 insertions(+), 5 deletions(-)

commit d2594c0ef22017f2fbf6eacd21aa74590982e36f
Author: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Date: Wed Feb 9 11:59:49 2011 +1030

cpumask: remove struct cpumask definition when CONFIG_CPUMASK_OFFSTACK=y

We're about to change CONFIG_CPUMASK_OFFSTACK so it only allocate
nr_cpu_ids bits for all cpumasks. We need to make sure that when
CONFIG_CPUMASK_OFFSTACK is set:

1) Noone uses the old bitmap ops, which use NR_CPUS bits (use cpumask_*)
2) Noone uses assignment of struct cpumask (use cpumask_copy)
3) Noone passes a struct cpumask (pass a pointer)
4) Noone declares them on the stack (use cpumask_var_t)

So we finally remove the definition of struct cpumask when
CONFIG_CPUMASK_OFFSTACK=y. This means that these usages will hit a compile
error the moment that config option is turned on.

Note that it also means you can't declare a static cpumask. You
should avoid this anyway (use cpumask_var_t), but there's a
deliberately-ugly workaround for special cases, using DECLARE_BITMAP()
and to_cpumask().

Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: anton@xxxxxxxxx
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Mike Travis <travis@xxxxxxx>

include/linux/cpumask.h | 15 +++++++++++++++
1 files changed, 15 insertions(+), 0 deletions(-)

commit 5a9c141a738da5bf0cdbab099ed62155fd47fb67
Author: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Date: Wed Feb 9 11:59:48 2011 +1030

cpumask: reduce cpumask_size

Now we're sure noone is using old cpumask operators, nor *cpumask, we can
allocate less bits safely. This reduces the memory usage of off-stack
cpumasks when CONFIG_CPUMASK_OFFSTACK=y but we don't have NR_CPUS actual
cpus.

Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: anton@xxxxxxxxx
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Mike Travis <travis@xxxxxxx>

include/linux/cpumask.h | 6 ++----
1 files changed, 2 insertions(+), 4 deletions(-)
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