Instead of dealing with sched classes inside each check_preempt_curr()
implementation, pull out this logic into the generic wakeup preemption
path.
This fixes a hang in KVM (and others) where we are waiting for the
stop machine thread to run ...
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Tested-by: Marcelo Tosatti <mtosatti@redhat.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1288891946.2039.31.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On use of trace_printk() there's a macro that determines if the format
is static or a variable. If it is static, it defaults to __trace_bprintk()
otherwise it uses __trace_printk().
A while ago, Lai Jiangshan added __trace_bprintk(). In that patch, we
discussed a way to allow modules to use it. The difference between
__trace_bprintk() and __trace_printk() is that for faster processing,
just the format and args are stored in the trace instead of running
it through a sprintf function. In order to do this, the format used
by the __trace_bprintk() had to be persistent.
See commit 1ba28e02a1
The problem comes with trace_bprintk() where the module is unloaded.
The pointer left in the buffer is still pointing to the format.
To solve this issue, the formats in the module were copied into kernel
core. If the same format was used, they would use the same copy (to prevent
memory leak). This all worked well until we tried to merge everything.
At the time this was written, Lai Jiangshan, Frederic Weisbecker,
Ingo Molnar and myself were all touching the same code. When this was
merged, we lost the part of it that was in module.c. This kept out the
copying of the formats and unloading the module could cause bad pointers
left in the ring buffer.
This patch adds back (with updates required for current kernel) the
module code that sets up the necessary pointers.
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Since the OPP API is only useful with an appropraite SoC-specific
implementation there is no point in offering the ability to enable
the API on general systems. Provide an ARCH_HAS OPP Kconfig symbol
which masks out the option unless selected by an implementation.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Nishanth Menon <nm@ti.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Heiko reported that the TASK_RUNNING check is not sufficient for
CONFIG_PREEMPT=y since we can get preempted with !TASK_RUNNING.
He suggested adding a ->se.on_rq test to the existing TASK_RUNNING
one, however TASK_RUNNING will always have ->se.on_rq, so we might as
well reduce that to a single test.
[ stop tasks should never get preempted, but its good to handle
this case correctly should this ever happen ]
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Currently we consider a sched domain to be well balanced when the imbalance
is less than the domain's imablance_pct. As the number of cores and threads
are increasing, current values of imbalance_pct (for example 25% for a
NUMA domain) are not enough to detect imbalances like:
a) On a WSM-EP system (two sockets, each having 6 cores and 12 logical threads),
24 cpu-hogging tasks get scheduled as 13 on one socket and 11 on another
socket. Leading to an idle HT cpu.
b) On a hypothetial 2 socket NHM-EX system (each socket having 8 cores and
16 logical threads), 16 cpu-hogging tasks can get scheduled as 9 on one
socket and 7 on another socket. Leaving one core in a socket idle
whereas in another socket we have a core having both its HT siblings busy.
While this issue can be fixed by decreasing the domain's imbalance_pct
(by making it a function of number of logical cpus in the domain), it
can potentially cause more task migrations across sched groups in an
overloaded case.
Fix this by using imbalance_pct only during newly_idle and busy
load balancing. And during idle load balancing, check if there
is an imbalance in number of idle cpu's across the busiest and this
sched_group or if the busiest group has more tasks than its weight that
the idle cpu in this_group can pull.
Reported-by: Nikhil Rao <ncrao@google.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1284760952.2676.11.camel@sbsiddha-MOBL3.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch corrects time tracking in samples. Without this patch
both time_enabled and time_running are bogus when user asks for
PERF_SAMPLE_READ.
One uses PERF_SAMPLE_READ to sample the values of other counters
in each sample. Because of multiplexing, it is necessary to know
both time_enabled, time_running to be able to scale counts correctly.
In this second version of the patch, we maintain a shadow
copy of ctx->time which allows us to compute ctx->time without
calling update_context_time() from NMI context. We avoid the
issue that update_context_time() must always be called with
ctx->lock held.
We do not keep shadow copies of the other event timings
because if the lead event is overflowing then it is active
and thus it's been scheduled in via event_sched_in() in
which case neither tstamp_stopped, tstamp_running can be modified.
This timing logic only applies to samples when PERF_SAMPLE_READ
is used.
Note that this patch does not address timing issues related
to sampling inheritance between tasks. This will be addressed
in a future patch.
With this patch, the libpfm4 example task_smpl now reports
correct counts (shown on 2.4GHz Core 2):
$ task_smpl -p 2400000000 -e unhalted_core_cycles:u,instructions_retired:u,baclears noploop 5
noploop for 5 seconds
IIP:0x000000004006d6 PID:5596 TID:5596 TIME:466,210,211,430 STREAM_ID:33 PERIOD:2,400,000,000 ENA=1,010,157,814 RUN=1,010,157,814 NR=3
2,400,000,254 unhalted_core_cycles:u (33)
2,399,273,744 instructions_retired:u (34)
53,340 baclears (35)
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <4cc6e14b.1e07e30a.256e.5190@mx.google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The futex_q struct has grown considerably over the last couple years. I
believe it now merits a static initializer to avoid uninitialized data
errors (having spent more time than I care to admit debugging an uninitialized
q.bitset in an experimental new op code).
With the key initializer built in, several of the FUTEX_KEY_INIT calls can
be removed.
V2: use a static variable instead of an init macro.
use a C99 initializer and don't rely on variable ordering in the struct.
V3: make futex_q_init const
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <1289252428-18383-1-git-send-email-dvhart@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In the early days we passed the mmap sem around. That became the
"int fshared" with the fast gup improvements. Then we added
"int clockrt" in places. This patch unifies these options as "flags".
[ tglx: Split out the stale fshared cleanup ]
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <1289250609-16304-1-git-send-email-dvhart@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The fast GUP changes stopped using the fshared flag in
put_futex_keys(), but we kept the interface the same.
Cleanup all stale users.
This patch is split out from Darren Harts combo patch which also
combines various flags. This way the changes are clearly separated.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Darren Hart <dvhart@linux.intel.com>
LKML-Reference: <1289250609-16304-1-git-send-email-dvhart@linux.intel.com>
REQ_HARDBARRIER is dead now, so remove the leftovers. What's left
at this point is:
- various checks inside the block layer.
- sanity checks in bio based drivers.
- now unused bio_empty_barrier helper.
- Xen blockfront use of BLKIF_OP_WRITE_BARRIER - it's dead for a while,
but Xen really needs to sort out it's barrier situaton.
- setting of ordered tags in uas - dead code copied from old scsi
drivers.
- scsi different retry for barriers - it's dead and should have been
removed when flushes were converted to FS requests.
- blktrace handling of barriers - removed. Someone who knows blktrace
better should add support for REQ_FLUSH and REQ_FUA, though.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Since commit 1dcc41bb (futex: Change 3rd arg of fetch_robust_entry()
to unsigned int*) some gcc versions decided to emit the following
warning:
kernel/futex.c: In function ‘exit_robust_list’:
kernel/futex.c:2492: warning: ‘next_pi’ may be used uninitialized in this function
The commit did not introduce the warning as gcc should have warned
before that commit as well. It's just gcc being silly.
The code path really can't result in next_pi being unitialized (or
should not), but let's keep the build clean. Annotate next_pi as an
uninitialized_var.
[ tglx: Addressed the same issue in futex_compat.c and massaged the
changelog ]
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Tested-by: Matt Fleming <matt@console-pimps.org>
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <1288897200-13008-1-git-send-email-dvhart@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Commit 4221a9918e "Add RCU check for
find_task_by_vpid()" introduced rcu_lockdep_assert to find_task_by_pid_ns.
Add rcu_read_lock/rcu_read_unlock to call find_task_by_vpid.
Tetsuo Handa wrote:
| Quoting from one of posts in that thead
| http://kerneltrap.org/mailarchive/linux-kernel/2010/2/8/4536388
|
|| Usually tasklist gives enough protection, but if copy_process() fails
|| it calls free_pid() lockless and does call_rcu(delayed_put_pid().
|| This means, without rcu lock find_pid_ns() can't scan the hash table
|| safely.
Thomas Gleixner wrote:
| We can remove the tasklist_lock while at it. rcu_read_lock is enough.
Patch also replaces thread_group_leader with has_group_leader_pid
in accordance to comment by Oleg Nesterov:
| ... thread_group_leader() check is not relaible without
| tasklist. If we race with de_thread() find_task_by_vpid() can find
| the new leader before it updates its ->group_leader.
|
| perhaps it makes sense to change posix_cpu_timer_create() to use
| has_group_leader_pid() instead, just to make this code not look racy
| and avoid adding new problems.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
LKML-Reference: <20101103165256.GD30053@swordfish.minsk.epam.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
s390 doesn't need FRAME_POINTERS in order to have a working function tracer.
We don't need frame pointers in order to get strack traces since we always
have valid backchains by using the -mkernel-backchain gcc option.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Commit d9ca07a05c ("watchdog: Avoid kernel crash when disabling
watchdog") introduces a section mismatch.
Now that we reference no_watchdog from non-__init code it can no longer
be __initdata.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
posix-cpu-timers.c correctly assumes that the dying process does
posix_cpu_timers_exit_group() and removes all !CPUCLOCK_PERTHREAD
timers from signal->cpu_timers list.
But, it also assumes that timer->it.cpu.task is always the group
leader, and thus the dead ->task means the dead thread group.
This is obviously not true after de_thread() changes the leader.
After that almost every posix_cpu_timer_ method has problems.
It is not simple to fix this bug correctly. First of all, I think
that timer->it.cpu should use struct pid instead of task_struct.
Also, the locking should be reworked completely. In particular,
tasklist_lock should not be used at all. This all needs a lot of
nontrivial and hard-to-test changes.
Change __exit_signal() to do posix_cpu_timers_exit_group() when
the old leader dies during exec. This is not the fix, just the
temporary hack to hide the problem for 2.6.37 and stable. IOW,
this is obviously wrong but this is what we currently have anyway:
cpu timers do not work after mt exec.
In theory this change adds another race. The exiting leader can
detach the timers which were attached to the new leader. However,
the window between de_thread() and release_task() is small, we
can pretend that sys_timer_create() was called before de_thread().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We can optimize kernel/relay.c::relay_alloc_page_array() slightly by
using vzalloc. The patch makes these changes:
- use vzalloc instead of vmalloc+memset.
- remove redundant local variable 'array'.
- declare local 'pa_size' as const.
Cuts down nicely on both source and object-code size.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Pekka Enberg <penberg@kernel.org>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
genirq: Fix up irq_node() for irq_data changes.
genirq: Add single IRQ reservation helper
genirq: Warn if enable_irq is called before irq is set up
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
semaphore: Remove mutex emulation
staging: Final semaphore cleanup
jbd2: Convert jbd2_slab_create_sem to mutex
hpfs: Convert sbi->hpfs_creation_de to mutex
Fix up trivial change/delete conflicts with deleted 'dream' drivers
(drivers/staging/dream/camera/{mt9d112.c,mt9p012_fox.c,mt9t013.c,s5k3e2fx.c})
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
jump label: Add work around to i386 gcc asm goto bug
x86, ftrace: Use safe noops, drop trap test
jump_label: Fix unaligned traps on sparc.
jump label: Make arch_jump_label_text_poke_early() optional
jump label: Fix error with preempt disable holding mutex
oprofile: Remove deprecated use of flush_scheduled_work()
oprofile: Fix the hang while taking the cpu offline
jump label: Fix deadlock b/w jump_label_mutex vs. text_mutex
jump label: Fix module __init section race
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Check irq_remapped instead of remapping_enabled in destroy_irq()
Normal syscall audit doesn't catch 5th argument of syscall. It also
doesn't catch the contents of userland structures pointed to be
syscall argument, so for both old and new mmap(2) ABI it doesn't
record the descriptor we are mapping. For old one it also misses
flags.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Protect the task lookups in audit_receive_msg() with rcu_read_lock()
instead of tasklist_lock and use lock/unlock_sighand to protect
against the exit race.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
audit_receive_msg() sends uninitialized data for AUDIT_TTY_GET when
the task was not found.
Send reply only when task was found.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
While auditing all tasklist_lock read_lock sites I stumbled over the
following call chain:
audit_prepare_user_tty()
read_lock(&tasklist_lock);
tty_audit_push_task();
mutex_lock(&buf->mutex);
--> buf->mutex is locked with preemption disabled.
Solve this by acquiring a reference to the task struct under
rcu_read_lock and call tty_audit_push_task outside of the preempt
disabled region.
Move all code which needs to be protected by sighand lock into
tty_audit_push_task() and use lock/unlock_sighand as we do not hold
tasklist_lock.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
I was doing some namespace checks and found some simple stuff in
audit that could be cleaned up. Make some functions static, and
put const on make_reply payload arg.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add support for matching by security label (e.g. SELinux context) of
the sender of an user-space audit record.
The audit filter code already allows user space to configure such
filters, but they were ignored during evaluation. This patch implements
evaluation of these filters.
For example, after application of this patch, PAM authentication logs
caused by cron can be disabled using
auditctl -a user,never -F subj_type=crond_t
Signed-off-by: Miloslav Trmac <mitr@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The kgdb_disable_hw_debug() was an architecture specific function for
disabling all hardware breakpoints on a per cpu basis when entering
the debug core.
This patch will remove the weak function kdbg_disable_hw_debug() and
change it into a call back which lives with the rest of hw breakpoint
call backs in struct kgdb_arch.
Signed-off-by: Dongdong Deng <dongdong.deng@windriver.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
The kdb_current legally be equal to NULL in the early boot of the x86
arch. The problem pcan be observed by booting with the kernel arguments:
earlyprintk=vga ekgdboc=kbd kgdbwait
The kdb shell will oops on entry and recursively fault because it
cannot get past the final stage of shell initialization.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Rusty pointed out that the per_cpu command uses up lots of space on
the stack and the cpu supress mask is probably not needed.
This patch removes the need for the supress mask as well as fixing up
the following problems with the kdb per_cpu command:
* The per_cpu command should allow an address as an argument
* When you have more data than can be displayed on one screen allow
the user to break out of the print loop.
Reported-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Some archs do not need to do anything special for jump labels on
startup (like MIPS). This patch adds a weak function stub for
arch_jump_label_text_poke_early();
Cc: Jason Baron <jbaron@redhat.com>
Cc: David Miller <davem@davemloft.net>
Cc: David Daney <ddaney@caviumnetworks.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <1286218615-24011-2-git-send-email-ddaney@caviumnetworks.com>
LKML-Reference: <20101015201037.703989993@goodmis.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Kprobes and jump label were having a race between mutexes that
was fixed by reordering the jump label. But this reordering
moved the jump label mutex into a preempt disable location.
This patch does a little fiddling to move the grabbing of
the jump label mutex from inside the preempt disable section
and still keep the order correct between the mutex and the
kprobes lock.
Reported-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jason Baron <jbaron@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (27 commits)
x86: allocate space within a region top-down
x86: update iomem_resource end based on CPU physical address capabilities
x86/PCI: allocate space from the end of a region, not the beginning
PCI: allocate bus resources from the top down
resources: support allocating space within a region from the top down
resources: handle overflow when aligning start of available area
resources: ensure callback doesn't allocate outside available space
resources: factor out resource_clip() to simplify find_resource()
resources: add a default alignf to simplify find_resource()
x86/PCI: MMCONFIG: fix region end calculation
PCI: Add support for polling PME state on suspended legacy PCI devices
PCI: Export some PCI PM functionality
PCI: fix message typo
PCI: log vendor/device ID always
PCI: update Intel chipset names and defines
PCI: use new ccflags variable in Makefile
PCI: add PCI_MSIX_TABLE/PBA defines
PCI: add PCI vendor id for STmicroelectronics
x86/PCI: irq and pci_ids patch for Intel Patsburg DeviceIDs
PCI: OLPC: Only enable PCI configuration type override on XO-1
...
register_kprobe() downs the 'text_mutex' and then calls
jump_label_text_reserved(), which downs the 'jump_label_mutex'.
However, the jump label code takes those mutexes in the reverse
order.
Fix by requiring the caller of jump_label_text_reserved() to do
the jump label locking via the newly added: jump_label_lock(),
jump_label_unlock(). Currently, kprobes is the only user
of jump_label_text_reserved().
Reported-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
LKML-Reference: <759032c48d5e30c27f0bba003d09bffa8e9f28bb.1285965957.git.jbaron@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Jump label uses is_module_text_address() to ensure that the module
__init sections are valid before updating them. However, between the
check for a valid module __init section and the subsequent jump
label update, the module's __init section could be freed out from under
us.
We fix this potential race by adding a notifier callback to the
MODULE_STATE_LIVE state. This notifier is called *after* the __init
section has been run but before it is going to be freed. In the
callback, the jump label code zeros the key value for any __init jump
code within the module, and we add a check for a non-zero key value when
we update jump labels. In this way we require no additional data
structures.
Thanks to Mathieu Desnoyers for pointing out this race condition.
Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
LKML-Reference: <c6f037b7598777668025ceedd9294212fd95fa34.1285965957.git.jbaron@redhat.com>
[ Renamed remove_module_init() to remove_jump_label_module_init()
as suggested by Masami Hiramatsu. ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-mn10300: (44 commits)
MN10300: Save frame pointer in thread_info struct rather than global var
MN10300: Change "Matsushita" to "Panasonic".
MN10300: Create a defconfig for the ASB2364 board
MN10300: Update the ASB2303 defconfig
MN10300: ASB2364: Add support for SMSC911X and SMC911X
MN10300: ASB2364: Handle the IRQ multiplexer in the FPGA
MN10300: Generic time support
MN10300: Specify an ELF HWCAP flag for MN10300 Atomic Operations Unit support
MN10300: Map userspace atomic op regs as a vmalloc page
MN10300: And Panasonic AM34 subarch and implement SMP
MN10300: Delete idle_timestamp from irq_cpustat_t
MN10300: Make various interrupt priority settings configurable
MN10300: Optimise do_csum()
MN10300: Implement atomic ops using atomic ops unit
MN10300: Make the FPU operate in non-lazy mode under SMP
MN10300: SMP TLB flushing
MN10300: Use the [ID]PTEL2 registers rather than [ID]PTEL for TLB control
MN10300: Make the use of PIDR to mark TLB entries controllable
MN10300: Rename __flush_tlb*() to local_flush_tlb*()
MN10300: AM34 erratum requires MMUCTR read and write on exception entry
...
* 'module' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
NULL-terminate all pci_device_id tables
(trivial) Fix compiler warning in kernel/modules.c
If the same resource is inserted to the resource tree (maybe not on
purpose), a dead loop will be created. In this situation, The kernel does
not report any warning or error :(
The command below will show a endless print.
#cat /proc/iomem
[akpm@linux-foundation.org: add WARN_ON()]
Signed-off-by: Huang Shijie <shijie8@gmail.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The taskstats interface uses microsecond granularity for the user and
system time values. The conversion from cputime to the taskstats values
uses the cputime_to_msecs primitive which effectively limits the
granularity to milliseconds. Add the cputime_to_usecs primitive for
architectures that have better, more precise CPU time values. Remove
cputime_to_msecs primitive because there are no more users left.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Luck Tony <tony.luck@intel.com>
Cc: Shailabh Nagar <nagar1234@in.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Shailabh Nagar <nagar@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Separate the finding of a task_struct by pid or tgid from filling the
taskstats data. This makes the code more readable.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move each taskstats command into a single function. This makes the code
more readable and makes it easier to add new commands.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
prepare_reply() sets up an skb for the response. The payload contains:
+--------------------------------+
| genlmsghdr - 4 bytes |
+--------------------------------+
| NLA header - 4 bytes | /* Aggregate header */
+-+------------------------------+
| | NLA header - 4 bytes | /* PID header */
| +------------------------------+
| | pid/tgid - 4 bytes |
| +------------------------------+
| | NLA header - 4 bytes | /* stats header */
| + -----------------------------+ <- oops. aligned on 4 byte boundary
| | struct taskstats - 328 bytes |
+-+------------------------------+
The start of the taskstats struct must be 8 byte aligned on IA64 (and
other systems with 8 byte alignment rules for 64-bit types) or runtime
alignment warnings will be issued.
This patch pads the pid/tgid field out to sizeof(long), which forces the
alignment of taskstats. The getdelays userspace code is ok with this
since it assumes 32-bit pid/tgid and then honors that header's length
field.
An array is used to avoid exposing kernel memory contents to userspace in
the response.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In /proc/stat, the number of per-IRQ event is shown by making a sum each
irq's events on all cpus. But we can make use of kstat_irqs().
kstat_irqs() do the same calculation, If !CONFIG_GENERIC_HARDIRQ,
it's not a big cost. (Both of the number of cpus and irqs are small.)
If a system is very big and CONFIG_GENERIC_HARDIRQ, it does
for_each_irq()
for_each_cpu()
- look up a radix tree
- read desc->irq_stat[cpu]
This seems not efficient. This patch adds kstat_irqs() for
CONFIG_GENRIC_HARDIRQ and change the calculation as
for_each_irq()
look up radix tree
for_each_cpu()
- read desc->irq_stat[cpu]
This reduces cost.
A test on (4096cpusp, 256 nodes, 4592 irqs) host (by Jack Steiner)
%time cat /proc/stat > /dev/null
Before Patch: 2.459 sec
After Patch : .561 sec
[akpm@linux-foundation.org: unexport kstat_irqs, coding-style tweaks]
[akpm@linux-foundation.org: fix unused variable 'per_irq_sum']
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: Jack Steiner <steiner@sgi.com>
Acked-by: Jack Steiner <steiner@sgi.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
find_new_reaper() releases and regrabs tasklist_lock but was missing
proper annotations. Add it. This remove following sparse warning:
warning: context imbalance in 'find_new_reaper' - unexpected unlock
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov pointed out we have to prevent multiple-threads-inside-exec
itself and we can reuse ->cred_guard_mutex for it. Yes, concurrent
execve() has no worth.
Let's move ->cred_guard_mutex from task_struct to signal_struct. It
naturally prevent multiple-threads-inside-exec.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
