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8391 commits

Author SHA1 Message Date
Thomas Gleixner
d0981a1b21 clocksource: Protect the watchdog rating changes with clocksource_mutex
Martin pointed out that commit 6ea41d2529 (clocksource: Call
clocksource_change_rating() outside of watchdog_lock) has a
theoretical reference count problem. The calls to
clocksource_change_rating() are now done outside of the clocksource
mutex and outside of the watchdog lock. A concurrent
clocksource_unregister() could remove the clock.

Split out the code which changes the rating from
clocksource_change_rating() into __clocksource_change_rating().

Protect the clocksource_watchdog_work() code sequence with the
clocksource_mutex() and call __clocksource_change_rating().

LKML-Reference: <alpine.LFD.2.00.0908171038420.2782@localhost.localdomain>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-08-19 11:42:48 +02:00
Steven Rostedt
de481560eb kconfig: keep config.gz around even if CONFIG_IKCONFIG_PROC is not set
If CONFIG_IKCONFIG is set but CONFIG_IKCONFIG_PROC is not, then
gcc will optimize the config.gz out, because nobody uses it.

This patch adds "__used" to the config.gz data to keep it around so that
code like extract-ikconfig can still find it.

[ Impact: allow extract-ikconfig to find config.gz ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-18 22:01:08 -04:00
Jiri Olsa
eda1e32855 tracing: handle broken names in ftrace filter
If one filter item (for set_ftrace_filter and set_ftrace_notrace) is being
setup by more than 1 consecutive writes (FTRACE_ITER_CONT flag), it won't
be handled corretly.

I used following program to test/verify:

[snip]
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>

int main(int argc, char **argv)
{
        int fd, i;
        char *file = argv[1];

        if (-1 == (fd = open(file, O_WRONLY))) {
                perror("open failed");
                return -1;
        }

        for(i = 0; i < (argc - 2); i++) {
                int len = strlen(argv[2+i]);
                int cnt, off = 0;

                while(len) {
                        cnt = write(fd, argv[2+i] + off, len);
                        len -= cnt;
                        off += cnt;
                }
        }

        close(fd);
        return 0;
}
[snip]

before change:
sh-4.0# echo > ./set_ftrace_filter
sh-4.0# /test ./set_ftrace_filter "sys" "_open "
sh-4.0# cat ./set_ftrace_filter
#### all functions enabled ####
sh-4.0#

after change:
sh-4.0# echo > ./set_ftrace_notrace
sh-4.0# test ./set_ftrace_notrace "sys" "_open "
sh-4.0# cat ./set_ftrace_notrace
sys_open
sh-4.0#

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <20090811152904.GA26065@jolsa.lab.eng.brq.redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-18 20:39:48 -04:00
KOSAKI Motohiro
0753ba01e1 mm: revert "oom: move oom_adj value"
The commit 2ff05b2b (oom: move oom_adj value) moveed the oom_adj value to
the mm_struct.  It was a very good first step for sanitize OOM.

However Paul Menage reported the commit makes regression to his job
scheduler.  Current OOM logic can kill OOM_DISABLED process.

Why? His program has the code of similar to the following.

	...
	set_oom_adj(OOM_DISABLE); /* The job scheduler never killed by oom */
	...
	if (vfork() == 0) {
		set_oom_adj(0); /* Invoked child can be killed */
		execve("foo-bar-cmd");
	}
	....

vfork() parent and child are shared the same mm_struct.  then above
set_oom_adj(0) doesn't only change oom_adj for vfork() child, it's also
change oom_adj for vfork() parent.  Then, vfork() parent (job scheduler)
lost OOM immune and it was killed.

Actually, fork-setting-exec idiom is very frequently used in userland program.
We must not break this assumption.

Then, this patch revert commit 2ff05b2b and related commit.

Reverted commit list
---------------------
- commit 2ff05b2b4e (oom: move oom_adj value from task_struct to mm_struct)
- commit 4d8b9135c3 (oom: avoid unnecessary mm locking and scanning for OOM_DISABLE)
- commit 8123681022 (oom: only oom kill exiting tasks with attached memory)
- commit 933b787b57 (mm: copy over oom_adj value at fork time)

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-18 16:31:13 -07:00
Huang Weiyi
b08dc3eba0 Security/SELinux: remove duplicated #include
Remove duplicated #include('s) in
  kernel/sysctl.c

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-08-19 08:09:09 +10:00
Linus Torvalds
dcd94dbdaf Merge branch 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  genirq: Wake up irq thread after action has been installed
2009-08-18 13:57:38 -07:00
Andreas Herrmann
294b0c9619 sched: Consolidate definition of variable sd in __build_sched_domains
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818110229.GM29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:45 +02:00
Andreas Herrmann
0601a88d8f sched: Separate out build of NUMA sched groups from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818110111.GL29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:44 +02:00
Andreas Herrmann
de616e36c7 sched: Separate out build of ALLNODES sched groups from __build_sched_domains
For the sake of completeness.
Now all calls to init_sched_build_groups() are contained in
build_sched_groups().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818110013.GK29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:44 +02:00
Andreas Herrmann
86548096f2 sched: Separate out build of CPU sched groups from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105928.GJ29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:43 +02:00
Andreas Herrmann
a2af04cdbb sched: Separate out build of MC sched groups from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105838.GI29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:43 +02:00
Andreas Herrmann
0e8e85c941 sched: Separate out build of SMT sched groups from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105751.GH29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:42 +02:00
Andreas Herrmann
d817353555 sched: Separate out build of SMT sched domain from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105703.GG29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:42 +02:00
Andreas Herrmann
410c408108 sched: Separate out build of MC sched domain from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105614.GF29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:41 +02:00
Andreas Herrmann
87cce6622c sched: Separate out build of CPU sched domain from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105455.GE29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:40 +02:00
Andreas Herrmann
7f4588f3aa sched: Separate out build of NUMA sched domain from __build_sched_domains
... to further strip down __build_sched_domains().

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105406.GD29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:40 +02:00
Andreas Herrmann
2109b99ee1 sched: Separate out allocation/free/goto-hell from __build_sched_domains
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105300.GC29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:39 +02:00
Andreas Herrmann
49a02c514d sched: Use structure to store local data in __build_sched_domains
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20090818105152.GB29515@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 18:35:39 +02:00
Thomas Gleixner
69ab849439 genirq: Wake up irq thread after action has been installed
The wake_up_process() of the new irq thread in __setup_irq() is too
early as the irqaction is not yet fully initialized especially
action->irq is not yet set. The interrupt thread might dereference the
wrong irq descriptor.

Move the wakeup after the action is installed and action->irq has been
set.

Reported-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Buesch <mb@bu3sch.de>
2009-08-18 17:22:43 +02:00
Ingo Molnar
f738eb1b63 perf_counter: Fix the PARISC build
PARISC does not build:

/home/mingo/tip/kernel/perf_counter.c: In function 'perf_counter_index':
/home/mingo/tip/kernel/perf_counter.c:2016: error: 'PERF_COUNTER_INDEX_OFFSET' undeclared (first use in this function)
/home/mingo/tip/kernel/perf_counter.c:2016: error: (Each undeclared identifier is reported only once
/home/mingo/tip/kernel/perf_counter.c:2016: error: for each function it appears in.)

As PERF_COUNTER_INDEX_OFFSET is not defined.

Now, we could define it in the architecture - but lets also provide
a core default of 0 (which happens to be what all but one
architecture uses at the moment).

Architectures that need a different index offset should set this
value in their asm/perf_counter.h files.

Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-18 11:34:13 +02:00
Zhaolei
f2d84b65b9 ftrace: Unify effect of writing to trace_options and option/*
"echo noglobal-clock > trace_options" can be used to change trace
clock but "echo 0 > options/global-clock" can't. The flag toggling
will be silently accepted without actually changing the clock callback.

We can fix it by using set_tracer_flags() in
trace_options_core_write().

Changelog:
v1->v2: Simplified switch() after Li Zefan <lizf@cn.fujitsu.com>'s
        suggestion

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: Steven Rostedt <srostedt@redhat.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-18 02:07:04 +02:00
Randy Dunlap
3a5209e3b2 trace_skb: fix build when CONFIG_NET is not enabled
Fix trace_skb_sources build when CONFIG_NET is not enabled:

kernel/built-in.o: In function `probe_skb_dequeue':
trace_skb_sources.c:(.text+0xd9152): undefined reference to `init_net'
trace_skb_sources.c:(.text+0xd9188): undefined reference to `dev_get_by_index'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-08-17 16:00:30 -07:00
Amerigo Wang
de809347ae timers: Drop write permission on /proc/timer_list
/proc/timer_list and /proc/slabinfo are not supposed to be
written, so there should be no write permissions on it.

Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: linux-mm@kvack.org
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Amerigo Wang <amwang@redhat.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
LKML-Reference: <20090817094525.6355.88682.sendpatchset@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 11:47:31 +02:00
Paul Mackerras
e1ac3614ff perf_counter: Check task on counter read IPI
In general, code in perf_counter.c that is called through an
IPI checks, for per-task counters, that the counter's task is
still the current task.  This is to handle the race condition
where the cpu switches from the task we want to another task in
the interval between sending the IPI and the IPI arriving and
being handled on the target CPU.

For some reason, __perf_counter_read is missing this check, yet
there is no reason why the race condition can't occur.  This
adds a check that the current task is the one we want.  If it
isn't, we just return.  In that case the counter->count value
should be up to date, since it will have been updated when the
counter was scheduled out, which must have happened since the
IPI was sent.

I don't have an example of an actual failure due to this race,
but it seems obvious that it could occur and we need to guard
against it.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <19076.63614.277861.368125@drongo.ozlabs.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 11:38:13 +02:00
Li Zefan
3be04b471b ftrace: Simplify seqfile code
Use seq_release_private().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A891AAB.8090701@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 11:25:10 +02:00
Li Zefan
2fc5f0cff4 trace_stack: Simplify seqfile code
Extract duplicate code in t_start() and t_next().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A891A91.4030602@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 11:25:09 +02:00
Li Zefan
97d53202a5 trace_stat: Fix missing entry in stat file
One entry is missing in the output of a stat file.

The cause is, when stat_seq_start() is called the 2nd time, we
should start from the (pos-1)th elem in the rbtree but not pos,
because pos == 0 is the header.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A891A65.70009@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 11:25:09 +02:00
Li Zefan
ba8b3a40ba tracing/syscalls: Fix to print parameter types
When syscall tracing was implemented as a tracer,
"syscall_arg_type" trace option could be set to enable the
display of syscall parameter types.

Now this option is gone since it's no longer a tracer, but the
code is still there but dead.

So we remove dead code and re-enable the printing of paramete
types via the verbose option:

  # echo verbose > trace_options
  # echo syscalls > set_event
  # cat trace
	...
        bash-3331  [000]    95.348937: sys_fcntl64 -> 0x1
        bash-3331  [000]    95.348942: sys_close(unsigned int fd: a)
	...

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
LKML-Reference: <4A891AF6.5050102@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 11:25:09 +02:00
Li Zefan
7ead8b8313 tracing/events: Add module tracepoints
Add trace points to trace module_load, module_free, module_get,
module_put and module_request, and use trace_event facility to
get the trace output.

Here's the sample output:

     TASK-PID    CPU#    TIMESTAMP  FUNCTION
        | |       |          |         |
    <...>-42    [000]     1.758380: module_request: fb0 wait=1 call_site=fb_open
    ...
    <...>-60    [000]     3.269403: module_load: scsi_wait_scan
    <...>-60    [000]     3.269432: module_put: scsi_wait_scan call_site=sys_init_module refcnt=0
    <...>-61    [001]     3.273168: module_free: scsi_wait_scan
    ...
    <...>-1021  [000]    13.836081: module_load: sunrpc
    <...>-1021  [000]    13.840589: module_put: sunrpc call_site=sys_init_module refcnt=-1
    <...>-1027  [000]    13.848098: module_get: sunrpc call_site=try_module_get refcnt=0
    <...>-1027  [000]    13.848308: module_get: sunrpc call_site=get_filesystem refcnt=1
    <...>-1027  [000]    13.848692: module_put: sunrpc call_site=put_filesystem refcnt=0
    ...
 modprobe-2587  [001]  1088.437213: module_load: trace_events_sample F
 modprobe-2587  [001]  1088.437786: module_put: trace_events_sample call_site=sys_init_module refcnt=0

Note:

- the taints flag can be 'F', 'C' and/or 'P' if mod->taints != 0

- the module refcnt is percpu, so it can be negative in a
  specific cpu

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <4A891B3C.5030608@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 11:25:08 +02:00
Thomas Gleixner
399b5da29b genirq: Support nested threaded irq handling
Interrupt chips which are behind a slow bus (i2c, spi ...) and
demultiplex other interrupt sources need to run their interrupt
handler in a thread. 

The demultiplexed interrupt handlers need to run in thread context as
well and need to finish before the demux handler thread can reenable
the interrupt line. So the easiest way is to run the sub device
handlers in the context of the demultiplexing handler thread.

To avoid that a separate thread is created for the subdevices the
function set_nested_irq_thread() is provided which sets the
IRQ_NESTED_THREAD flag in the interrupt descriptor.

A driver which calls request_threaded_irq() must not be aware of the
fact that the threaded handler is called in the context of the
demultiplexing handler thread. The setup code checks the
IRQ_NESTED_THREAD flag which was set from the irq chip setup code and
does not setup a separate thread for the interrupt. The primary
function which is provided by the device driver is replaced by an
internal dummy function which warns when it is called.

For the demultiplexing handler a helper function handle_nested_irq()
is provided which calls the demux interrupt thread function in the
context of the caller and does the proper interrupt accounting and
takes the interrupt disabled status of the demultiplexed subdevice
into account.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Trilok Soni <soni.trilok@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Brian Swetland <swetland@google.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: m.szyprowski@samsung.com
Cc: t.fujak@samsung.com
Cc: kyungmin.park@samsung.com,
Cc: David Brownell <david-b@pacbell.net>
Cc: Daniel Ribeiro <drwyrm@gmail.com>
Cc: arve@android.com
Cc: Barry Song <21cnbao@gmail.com>
2009-08-17 10:54:05 +02:00
Thomas Gleixner
70aedd24d2 genirq: Add buslock support
Some interrupt chips are connected to a "slow" bus (i2c, spi ...). The
bus access needs to sleep and therefor cannot be called in atomic
contexts.

Some of the generic interrupt management functions like disable_irq(),
enable_irq() ... call interrupt chip functions with the irq_desc->lock
held and interrupts disabled. This does not work for such devices.

Provide a separate synchronization mechanism for such interrupt
chips. The irq_chip structure is extended by two optional functions
(bus_lock and bus_sync_and_unlock).

The idea is to serialize the bus access for those operations in the
core code so that drivers which are behind that bus operated interrupt
controller do not have to worry about it and just can use the normal
interfaces. To achieve this we add two function pointers to the
irq_chip: bus_lock and bus_sync_unlock.

bus_lock() is called to serialize access to the interrupt controller
bus.

Now the core code can issue chip->mask/unmask ... commands without
changing the fast path code at all. The chip implementation merily
stores that information in a chip private data structure and
returns. No bus interaction as these functions are called from atomic
context.

After that bus_sync_unlock() is called outside the atomic context. Now
the chip implementation issues the bus commands, waits for completion
and unlocks the interrupt controller bus.

The irq_chip implementation as pseudo code:

struct irq_chip_data {
       struct mutex   mutex;
       unsigned int   irq_offset;
       unsigned long  mask;
       unsigned long  mask_status;
}

static void bus_lock(unsigned int irq)
{
        struct irq_chip_data *data = get_irq_desc_chip_data(irq);

        mutex_lock(&data->mutex);
}

static void mask(unsigned int irq)
{
        struct irq_chip_data *data = get_irq_desc_chip_data(irq);

        irq -= data->irq_offset;
        data->mask |= (1 << irq);
}

static void unmask(unsigned int irq)
{
        struct irq_chip_data *data = get_irq_desc_chip_data(irq);

        irq -= data->irq_offset;
        data->mask &= ~(1 << irq);
}

static void bus_sync_unlock(unsigned int irq)
{
        struct irq_chip_data *data = get_irq_desc_chip_data(irq);

        if (data->mask != data->mask_status) {
                do_bus_magic_to_set_mask(data->mask);
                data->mask_status = data->mask;
        }
        mutex_unlock(&data->mutex);
}

The device drivers can use request_threaded_irq, free_irq, disable_irq
and enable_irq as usual with the only restriction that the calls need
to come from non atomic context.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Trilok Soni <soni.trilok@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Brian Swetland <swetland@google.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: m.szyprowski@samsung.com
Cc: t.fujak@samsung.com
Cc: kyungmin.park@samsung.com,
Cc: David Brownell <david-b@pacbell.net>
Cc: Daniel Ribeiro <drwyrm@gmail.com>
Cc: arve@android.com
Cc: Barry Song <21cnbao@gmail.com>
2009-08-17 10:54:05 +02:00
Thomas Gleixner
b25c340c19 genirq: Add oneshot support
For threaded interrupt handlers we expect the hard interrupt handler
part to mask the interrupt on the originating device. The interrupt
line itself is reenabled after the hard interrupt handler has
executed.

This requires access to the originating device from hard interrupt
context which is not always possible. There are devices which can only
be accessed via a bus (i2c, spi, ...). The bus access requires thread
context. For such devices we need to keep the interrupt line masked
until the threaded handler has executed.

Add a new flag IRQF_ONESHOT which allows drivers to request that the
interrupt is not unmasked after the hard interrupt context handler has
been executed and the thread has been woken. The interrupt line is
unmasked after the thread handler function has been executed.

Note that for now IRQF_ONESHOT cannot be used with IRQF_SHARED to
avoid complex accounting mechanisms.

For oneshot interrupts the primary handler simply returns
IRQ_WAKE_THREAD and does nothing else. A generic implementation
irq_default_primary_handler() is provided to avoid useless copies all
over the place. It is automatically installed when
request_threaded_irq() is called with handler=NULL and
thread_fn!=NULL.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Trilok Soni <soni.trilok@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Brian Swetland <swetland@google.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: m.szyprowski@samsung.com
Cc: t.fujak@samsung.com
Cc: kyungmin.park@samsung.com,
Cc: David Brownell <david-b@pacbell.net>
Cc: Daniel Ribeiro <drwyrm@gmail.com>
Cc: arve@android.com
Cc: Barry Song <21cnbao@gmail.com>
2009-08-17 10:54:05 +02:00
Li Zefan
96004bb2a1 lockdep: Simplify lock_stat seqfile code
- make ls_next() call ls_start()
- remove redundant code in lock_stat_release()

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A88ED6B.6030602@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 09:54:41 +02:00
Li Zefan
12aac19d4b lockdep: Simplify lockdep_chains seqfile code
- make lc_next() call lc_start()
- use lock_chains directly instead of storing it in m->private

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A88ED57.5060609@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 09:54:41 +02:00
Li Zefan
8109e1de85 lockdep: Simplify lockdep seqfile code
Use seq_list_start_head() and seq_list_next().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A88ED41.5000000@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 09:54:40 +02:00
Li Zefan
e9d65725bd lockdep: Fix missing entries in /proc/lock_chains
Two entries are missing in the output of /proc/lock_chains.

One is chains[1]. When lc_next() is called the 1st time,
chains[0] is returned. And when it's called the 2nd time,
chains[2] is returned.

The other missing ons is, when lc_start() is called the 2nd
time, we should start from chains[@pos-1] but not chains[@pos],
because pos == 0 is the header.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A88ED25.2040306@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 09:54:40 +02:00
Li Zefan
212274347f lockdep: Fix missing entry in /proc/lock_stat
One entry is missing in the output of /proc/lock_stat.

The cause is, when ls_start() is called the 2nd time, we should
start from stats[@pos-1] but not stats[@pos], because pos == 0
is the header.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4A88ED15.20800@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-17 09:54:39 +02:00
Eric Paris
788084aba2 Security/SELinux: seperate lsm specific mmap_min_addr
Currently SELinux enforcement of controls on the ability to map low memory
is determined by the mmap_min_addr tunable.  This patch causes SELinux to
ignore the tunable and instead use a seperate Kconfig option specific to how
much space the LSM should protect.

The tunable will now only control the need for CAP_SYS_RAWIO and SELinux
permissions will always protect the amount of low memory designated by
CONFIG_LSM_MMAP_MIN_ADDR.

This allows users who need to disable the mmap_min_addr controls (usual reason
being they run WINE as a non-root user) to do so and still have SELinux
controls preventing confined domains (like a web server) from being able to
map some area of low memory.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2009-08-17 15:09:11 +10:00
Darren Hart
84bc4af590 futex: Detect mismatched requeue targets
There is currently no check to ensure that userspace uses the same
futex requeue target (uaddr2) in futex_requeue() that the waiter used
in futex_wait_requeue_pi().  A mismatch here could very unexpected
results as the waiter assumes it either wakes on uaddr1 or uaddr2. We
could detect this on wakeup in the waiter, but the cleanup is more
intense after the improper requeue has occured.

This patch stores the waiter's expected requeue target in a new
requeue_pi_key pointer in the futex_q which futex_requeue() checks
prior to attempting to do a proxy lock acquistion or a requeue when
requeue_pi=1. If they don't match, return -EINVAL from futex_requeue,
aborting the requeue of any remaining waiters.

Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Dinakar Guniguntala <dino@in.ibm.com>
Cc: John Stultz <johnstul@us.ibm.com>
LKML-Reference: <20090814003650.14634.63916.stgit@Aeon>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-16 10:59:05 +02:00
Josh Triplett
684ca5cc9a rcu: Fix typo in rcu_irq_exit() comment header
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: josht@linux.vnet.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: hugh.dickins@tiscali.co.uk
Cc: benh@kernel.crashing.org
LKML-Reference: <1250355231169-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-15 19:02:09 +02:00
Paul E. McKenney
b612ba804b rcu: Make rcupreempt_trace.c look at offline CPUs
Given that offline CPUs can now have non-zero counters, we need
to dump counters for offline CPUs as well as for online CPUs.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: josht@linux.vnet.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: hugh.dickins@tiscali.co.uk
Cc: benh@kernel.crashing.org
LKML-Reference: <12503552313921-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-15 19:02:09 +02:00
Paul E. McKenney
8064d54929 rcu: Make preemptable RCU scan all CPUs when summing RCU counters
This patch eliminates the counter-moving during CPU-offline
notifiers, eliminating potential confusion if counters are
scanned during counter-movement process.

This confusion could result in premature ending of an RCU grace
period. For example, if there are two tasks in RCU read-side
critical sections (so that the sum of the counters is two), and
the counter for the CPU going offline is -2, then moving the
count to another CPU can result in the sum momentarily
appearing to be zero.  Since there are no memory barriers in
either case, many more such scenarios are possible.

So just don't move the counts!!!

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: josht@linux.vnet.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: hugh.dickins@tiscali.co.uk
Cc: benh@kernel.crashing.org
LKML-Reference: <12503552312863-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-15 19:02:08 +02:00
Paul E. McKenney
2e59755808 rcu: Simplify RCU CPU-hotplug notification
Use the new cpu_notifier() API to simplify RCU's CPU-hotplug
notifiers, collapsing down to a single such notifier.

This makes it trivial to provide the notifier-ordering
guarantee that rcu_barrier() depends on.

Also remove redundant open_softirq() calls from Hierarchical
RCU notifier.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: josht@linux.vnet.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: hugh.dickins@tiscali.co.uk
Cc: benh@kernel.crashing.org
LKML-Reference: <12503552312510-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-15 19:02:08 +02:00
Paul E. McKenney
27569620c7 rcu: Split hierarchical RCU initialization into boot-time and CPU-online pieces
This patch divides the rcutree initialization into boot-time
and hotplug-time components, so that the tree data structures
are guaranteed to be fully linked at boot time regardless of
what might happen in CPU hotplug operations.

This makes RCU more resilient against CPU hotplug misbehavior
(and vice versa), but more importantly, does a better job of
compartmentalizing the code.

Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: josht@linux.vnet.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: hugh.dickins@tiscali.co.uk
Cc: benh@kernel.crashing.org
LKML-Reference: <1250355231152-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-15 19:02:07 +02:00
Ingo Molnar
fa08661af8 Merge commit 'v2.6.31-rc6' into core/rcu
Merge reason: the branch was on pre-rc1 .30, update to latest.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-15 18:56:13 +02:00
Thomas Gleixner
6ea41d252f clocksource: Call clocksource_change_rating() outside of watchdog_lock
The changes to the watchdog logic introduced a lock inversion between
watchdog_lock and clocksource_mutex. Change the rating outside of
watchdog_lock to avoid it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-15 13:20:42 +02:00
Martin Schwidefsky
23970e389e timekeeping: Introduce read_boot_clock
Add the new function read_boot_clock to get the exact time the system
has been started. For architectures without support for exact boot
time a new weak function is added that returns 0.  Use the exact boot
time to initialize wall_to_monotonic, or xtime if the read_boot_clock
returned 0.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Daniel Walker <dwalker@fifo99.com>
LKML-Reference: <20090814134811.296703241@de.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-15 10:55:47 +02:00
Martin Schwidefsky
d4f587c67f timekeeping: Increase granularity of read_persistent_clock()
The persistent clock of some architectures (e.g. s390) have a
better granularity than seconds. To reduce the delta between the
host clock and the guest clock in a virtualized system change the 
read_persistent_clock function to return a struct timespec.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Daniel Walker <dwalker@fifo99.com>
LKML-Reference: <20090814134811.013873340@de.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-15 10:55:46 +02:00
Martin Schwidefsky
75c5158f70 timekeeping: Update clocksource with stop_machine
update_wall_time calls change_clocksource HZ times per second to check
if a new clock source is available. In close to 100% of all calls
there is no new clock. Replace the tick based check by an update done
with stop_machine.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Daniel Walker <dwalker@fifo99.com>
LKML-Reference: <20090814134810.711836357@de.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-15 10:55:46 +02:00
Martin Schwidefsky
2ba2a3054f timekeeping: Add timekeeper read_clock helper functions
Add timekeeper_read_clock_ntp and timekeeper_read_clock_raw and use
them for getnstimeofday, ktime_get, ktime_get_ts and getrawmonotonic.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Daniel Walker <dwalker@fifo99.com>
LKML-Reference: <20090814134810.435105711@de.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-15 10:55:46 +02:00