At the moment, a lot of load balancing code that is irrelevant to non
SMP systems gets included during non SMP builds.
This patch addresses this issue and reduces the binary size on non
SMP systems:
text data bss dec hex filename
10983 28 1192 12203 2fab sched.o.before
10739 28 1192 11959 2eb7 sched.o.after
Signed-off-by: Peter Williams <pwil3058@bigpond.net.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
At the moment, balance_tasks() provides low level functionality for both
move_tasks() and move_one_task() (indirectly) via the load_balance()
function (in the sched_class interface) which also provides dual
functionality. This dual functionality complicates the interfaces and
internal mechanisms and makes the run time overhead of operations that
are called with two run queue locks held.
This patch addresses this issue and reduces the overhead of these
operations.
Signed-off-by: Peter Williams <pwil3058@bigpond.net.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
- replace "cont" with "cgrp" in a few places in the CFS cgroup code,
- use write_uint rather than write for cpu.shares write function
Signed-off-by: Paul Menage <menage@google.com>
Acked-by : Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
profile=sleep only works if CONFIG_SCHEDSTATS is set. This patch notes
the limitation in Documentation/kernel-parameters.txt and prints a
warning at boot-time if profile=sleep is used without CONFIG_SCHEDSTAT.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
A full register dump along with stack backtrace would make the
"scheduling while atomic" message more helpful. Use show_regs() instead
of dump_stack() for this. We already know we're atomic in here (that is
why this function was called) so show_regs()'s atomicity expectations
are guaranteed.
Also, modify the output of the "BUG: scheduling while atomic:" header a
bit to keep task->comm and task->pid together and preempt_count() after
them.
Signed-off-by: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
clean up sched_domain_debug().
this also shrinks the code a bit:
text data bss dec hex filename
50474 4306 480 55260 d7dc sched.o.before
50404 4306 480 55190 d796 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Jeff Dike noticed that wait_for_completion_interruptible()'s prototype
had a mismatched fastcall.
Fix this by removing the fastcall attributes from all the completion APIs.
Found-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
commit 029190c515 (cpuset
sched_load_balance flag) was not tested SCHED_DEBUG enabled as
committed as it dereferences NULL when used and it reordered
the sysctl registration to cause it to never show any domains
or their tunables.
Fixes:
1) restore arch_init_sched_domains ordering
we can't walk the domains before we build them
presently we register cpus with empty directories (no domain
directories or files).
2) make unregister_sched_domain_sysctl do nothing when already unregistered
detach_destroy_domains is now called one set of cpus at a time
unregister_syctl dereferences NULL if called with a null.
While the the function would always dereference null if called
twice, in the previous code it was always called once and then
was followed a register. So only the hidden bug of the
sysctl_root_table not being allocated followed by an attempt to
free it would have shown the error.
3) always call unregister and register in partition_sched_domains
The code is "smart" about unregistering only needed domains.
Since we aren't guaranteed any calls to unregister, always
unregister. Without calling register on the way out we
will not have a table or any sysctl tree.
4) warn if register is called without unregistering
The previous table memory is lost, leaving pointers to the
later freed memory in sysctl and leaking the memory of the
tables.
Before this patch on a 2-core 4-thread box compiled for SMT and NUMA,
the domains appear empty (there are actually 3 levels per cpu). And as
soon as two domains a null pointer is dereferenced (unreliable in this
case is stack garbage):
bu19a:~# ls -R /proc/sys/kernel/sched_domain/
/proc/sys/kernel/sched_domain/:
cpu0 cpu1 cpu2 cpu3
/proc/sys/kernel/sched_domain/cpu0:
/proc/sys/kernel/sched_domain/cpu1:
/proc/sys/kernel/sched_domain/cpu2:
/proc/sys/kernel/sched_domain/cpu3:
bu19a:~# mkdir /dev/cpuset
bu19a:~# mount -tcpuset cpuset /dev/cpuset/
bu19a:~# cd /dev/cpuset/
bu19a:/dev/cpuset# echo 0 > sched_load_balance
bu19a:/dev/cpuset# mkdir one
bu19a:/dev/cpuset# echo 1 > one/cpus
bu19a:/dev/cpuset# echo 0 > one/sched_load_balance
Unable to handle kernel paging request for data at address 0x00000018
Faulting instruction address: 0xc00000000006b608
NIP: c00000000006b608 LR: c00000000006b604 CTR: 0000000000000000
REGS: c000000018d973f0 TRAP: 0300 Not tainted (2.6.23-bml)
MSR: 9000000000009032 <EE,ME,IR,DR> CR: 28242442 XER: 00000000
DAR: 0000000000000018, DSISR: 0000000040000000
TASK = c00000001912e340[1987] 'bash' THREAD: c000000018d94000 CPU: 2
..
NIP [c00000000006b608] .unregister_sysctl_table+0x38/0x110
LR [c00000000006b604] .unregister_sysctl_table+0x34/0x110
Call Trace:
[c000000018d97670] [c000000007017270] 0xc000000007017270 (unreliable)
[c000000018d97720] [c000000000058710] .detach_destroy_domains+0x30/0xb0
[c000000018d977b0] [c00000000005cf1c] .partition_sched_domains+0x1bc/0x230
[c000000018d97870] [c00000000009fdc4] .rebuild_sched_domains+0xb4/0x4c0
[c000000018d97970] [c0000000000a02e8] .update_flag+0x118/0x170
[c000000018d97a80] [c0000000000a1768] .cpuset_common_file_write+0x568/0x820
[c000000018d97c00] [c00000000009d95c] .cgroup_file_write+0x7c/0x180
[c000000018d97cf0] [c0000000000e76b8] .vfs_write+0xe8/0x1b0
[c000000018d97d90] [c0000000000e810c] .sys_write+0x4c/0x90
[c000000018d97e30] [c00000000000852c] syscall_exit+0x0/0x40
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
As it is some callers of synchronize_irq rely on memory barriers
to provide synchronisation against the IRQ handlers. For example,
the tg3 driver does
tp->irq_sync = 1;
smp_mb();
synchronize_irq();
and then in the IRQ handler:
if (!tp->irq_sync)
netif_rx_schedule(dev, &tp->napi);
Unfortunately memory barriers only work well when they come in
pairs. Because we don't actually have memory barriers on the
IRQ path, the memory barrier before the synchronize_irq() doesn't
actually protect us.
In particular, synchronize_irq() may return followed by the
result of netif_rx_schedule being made visible.
This patch (mostly written by Linus) fixes this by using spin
locks instead of memory barries on the synchronize_irq() path.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix kernel-doc for auditsc parameter changes.
Warning(linux-2.6.23-git17//kernel/auditsc.c:1623): No description found for parameter 'dentry'
Warning(linux-2.6.23-git17//kernel/auditsc.c:1666): No description found for parameter 'dentry'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm:
KVM: Use new smp_call_function_mask() in kvm_flush_remote_tlbs()
sched: don't clear PF_VCPU in scheduler
KVM: Improve local apic timer wraparound handling
KVM: Fix local apic timer divide by zero
KVM: Move kvm_guest_exit() after local_irq_enable()
KVM: x86 emulator: fix access registers for instructions with ModR/M byte and Mod = 3
KVM: VMX: Force vm86 mode if setting flags during real mode
KVM: x86 emulator: implement 'movnti mem, reg'
KVM: VMX: Reset mmu context when entering real mode
KVM: VMX: Handle NMIs before enabling interrupts and preemption
KVM: MMU: Set shadow pte atomically in mmu_pte_write_zap_pte()
KVM: x86 emulator: fix repne/repnz decoding
KVM: x86 emulator: fix merge screwup due to emulator split
Gabriel C reported that modprobing appletalk on current git gives a
warning in dmesg :
"sysctl table check failed: /net/appletalk .3.7 procname does not match binary path procname"
Oops. My apologies it appears I made a mistake when creating my table
to check up on sysctl values.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Tested-by: Gabriel C <nix.or.die@googlemail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
New kind of audit rule predicates: "object is visible in given subtree".
The part that can be sanely implemented, that is. Limitations:
* if you have hardlink from outside of tree, you'd better watch
it too (or just watch the object itself, obviously)
* if you mount something under a watched tree, tell audit
that new chunk should be added to watched subtrees
* if you umount something in a watched tree and it's still mounted
elsewhere, you will get matches on events happening there. New command
tells audit to recalculate the trees, trimming such sources of false
positives.
Note that it's _not_ about path - if something mounted in several places
(multiple mount, bindings, different namespaces, etc.), the match does
_not_ depend on which one we are using for access.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (74 commits)
fix do_sys_open() prototype
sysfs: trivial: fix sysfs_create_file kerneldoc spelling mistake
Documentation: Fix typo in SubmitChecklist.
Typo: depricated -> deprecated
Add missing profile=kvm option to Documentation/kernel-parameters.txt
fix typo about TBI in e1000 comment
proc.txt: Add /proc/stat field
small documentation fixes
Fix compiler warning in smount example program from sharedsubtree.txt
docs/sysfs: add missing word to sysfs attribute explanation
documentation/ext3: grammar fixes
Documentation/java.txt: typo and grammar fixes
Documentation/filesystems/vfs.txt: typo fix
include/asm-*/system.h: remove unused set_rmb(), set_wmb() macros
trivial copy_data_pages() tidy up
Fix typo in arch/x86/kernel/tsc_32.c
file link fix for Pegasus USB net driver help
remove unused return within void return function
Typo fixes retrun -> return
x86 hpet.h: remove broken links
...
Weird I thought I had written the makefile so this would be handled. Oh
well this should fix it.
Sorry about that.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-and-tested-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change the loop style of copy_data_pages() to remove a duplicate condition.
Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Fix the various misspellings of "system", controller", "interrupt" and
"[un]necessary".
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (41 commits)
ACPICA: hw: Don't carry spinlock over suspend
ACPICA: hw: remove use_lock flag from acpi_hw_register_{read, write}
ACPI: cpuidle: port idle timer suspend/resume workaround to cpuidle
ACPI: clean up acpi_enter_sleep_state_prep
Hibernation: Make sure that ACPI is enabled in acpi_hibernation_finish
ACPI: suppress uninitialized var warning
cpuidle: consolidate 2.6.22 cpuidle branch into one patch
ACPI: thinkpad-acpi: skip blanks before the data when parsing sysfs
ACPI: AC: Add sysfs interface
ACPI: SBS: Add sysfs alarm
ACPI: SBS: Add ACPI_PROCFS around procfs handling code.
ACPI: SBS: Add support for power_supply class (and sysfs)
ACPI: SBS: Make SBS reads table-driven.
ACPI: SBS: Simplify data structures in SBS
ACPI: SBS: Split host controller (ACPI0001) from SBS driver (ACPI0002)
ACPI: EC: Add new query handler to list head.
ACPI: Add acpi_bus_generate_event4() function
ACPI: Battery: add sysfs alarm
ACPI: Battery: Add sysfs support
ACPI: Battery: Misc clean-ups, no functional changes
...
Fix up conflicts in drivers/misc/thinkpad_acpi.[ch] manually
