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There are reasons for kernel code to ask for, and use, performance
counters.
For example, in CPU freq governors this tends to be a good idea, but
there are other examples possible as well of course.
This patch adds the needed bits to do enable this functionality; they
have been tested in an experimental cpufreq driver that I'm working on,
and the changes are all that I needed to access counters properly.
[fweisbec@gmail.com: added pid to perf_event_create_kernel_counter so
that we can profile a particular task too
TODO: Have a better error reporting, don't just return NULL in fail
case.]
v2: Remove the wrong comment about the fact
perf_event_create_kernel_counter must be called from a kernel
thread.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: "K.Prasad" <prasad@linux.vnet.ibm.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jan Kiszka <jan.kiszka@web.de>
Cc: Avi Kivity <avi@redhat.com>
LKML-Reference: <20090925122556.2f8bd939@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
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Conflicts:
kernel/Makefile
kernel/trace/Makefile
kernel/trace/trace.h
samples/Makefile
Merge reason: We need to be uptodate with the perf events development
branch because we plan to rewrite the breakpoints API on top of
perf events.
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In each case, if the NULL test on thread is needed, then the
dereference should be after the NULL test.
A simplified version of the semantic match that detects this
problem is as follows (http://coccinelle.lip6.fr/):
// <smpl>
@match exists@
expression x, E;
identifier fld;
@@
* x->fld
... when != \(x = E\|&x\)
* x == NULL
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
LKML-Reference: <Pine.LNX.4.64.0910170842500.9213@ask.diku.dk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Now that we can filter based on fields via perf record, people
will start using filter expressions and will expect them to
be obvious.
The primary way to see which fields are available is by looking
at the trace output, such as:
gcc-18676 [000] 343.011728: irq_handler_entry: irq=0 handler=timer
cc1-18677 [000] 343.012727: irq_handler_entry: irq=0 handler=timer
cc1-18677 [000] 343.032692: irq_handler_entry: irq=0 handler=timer
cc1-18677 [000] 343.033690: irq_handler_entry: irq=0 handler=timer
cc1-18677 [000] 343.034687: irq_handler_entry: irq=0 handler=timer
cc1-18677 [000] 343.035686: irq_handler_entry: irq=0 handler=timer
cc1-18677 [000] 343.036684: irq_handler_entry: irq=0 handler=timer
While 'irq==0' filters work, the 'handler==<x>' filter expression
does not work:
$ perf record -R -f -a -e irq:irq_handler_entry --filter handler=timer sleep 1
Error: failed to set filter with 22 (Invalid argument)
The problem is that while an 'irq' field exists and is recognized
as a filter field - 'handler' does not exist - its name is 'name'
in the output.
To solve this, we need to synchronize the printout and the field
names, wherever possible.
In cases where the printout prints a non-field, we enclose
that information in square brackets, such as:
perf-1380 [013] 724.903505: softirq_exit: vec=9 [action=RCU]
perf-1380 [013] 724.904482: softirq_exit: vec=1 [action=TIMER]
This way users can use filter expressions more intuitively: all
fields that show up as 'primary' (non-bracketed) information is
filterable.
This patch harmonizes the field names for all irq, bkl, power,
sched and timer events.
We might in fact think about dropping the print format bit of
generic tracepoints altogether, and just print the fields that
are being recorded.
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
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>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Américo Wang noticed that we have a locking imbalance in the
error paths of ftrace_profile_set_filter(), causing potential
leakage of event_mutex.
Also clean up other error codepaths related to event_mutex
while at it.
Plus fix an initialized variable in the subsystem filter code.
Reported-by: Américo Wang <xiyou.wangcong@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <2375c9f90910150247u5ccb8e2at58c764e385ffa490@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Add a new option "--filter <filter_str>" to perf record, and
it should be right after "-e trace_point":
#./perf record -R -f -e irq:irq_handler_entry --filter irq==18
^C
# ./perf trace
perf-4303 ... irq_handler_entry: irq=18 handler=eth0
init-0 ... irq_handler_entry: irq=18 handler=eth0
init-0 ... irq_handler_entry: irq=18 handler=eth0
init-0 ... irq_handler_entry: irq=18 handler=eth0
init-0 ... irq_handler_entry: irq=18 handler=eth0
See Documentation/trace/events.txt for the syntax of filter
expressions.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <4AD6955F.90602@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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- Add an ioctl to allocate a filter for a perf event.
- Free the filter when the associated perf event is to be freed.
- Do the filtering in perf_swevent_match().
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <4AD69546.8050401@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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"==" will always do a full match, and "~" will do a glob match.
In the future, we may add "=~" for regex match.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <4AD69528.3050309@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Change:
for_each_pred
for_each_subsystem
To:
for_each_subsystem
for_each_pred
This change also prepares for later patches.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <4AD69502.8060903@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Merge reason: to add event filter support we need the following
commits from the tracing tree:
3f6fe06: tracing/filters: Unify the regex parsing helpers
1889d20: tracing/filters: Provide basic regex support
737f453: tracing/filters: Cleanup useless headers
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The (char *) for all the static strings was a fix for the
symptom and not the disease. The real issue was that the
function prototypes needed to be declared "const char *".
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194400.635935008@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The opterators '-' and '+' are not handled in the trace print
format.
To do: '++' and '--'.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194400.330843045@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Add the irqs disabled, preemption count, need resched, and other
info that is shown in the latency format of ftrace.
# perf trace -l
perf-16457 2..s2. 53636.260344: kmem_cache_free: call_site=ffffffff811198f
perf-16457 2..s2. 53636.264330: kmem_cache_free: call_site=ffffffff811198f
perf-16457 2d.s4. 53636.300006: kmem_cache_free: call_site=ffffffff810d889
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194400.076588953@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The ftrace output events can have either arguments or no
arguments. The parser needs to be able to handle both.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194359.790221427@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The bprintk parsing was broken in more ways than one.
The file parsing was incorrect, and the words used by the
arguments are always 4 bytes aligned, even on 64-bit machines.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194359.520931637@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Even though an event may fail to parse, we should not kill the
entire report. The trace should still be able to show what it
can.
If an event fails to parse, a warning is printed, and the output
continues.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194359.190809589@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The trace format files now have a "signed" field. But we should
still be able to handle the kernels that do not have this field.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194358.888239553@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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New lines between args in the trace format can break the
parsing. This should not be the case.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194358.637991808@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The '*' is currently only treated as a multiplication, and it
needs to be handled as a typecast pointer.
This is the version used by trace-cmd.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194358.409327875@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The array used by the ftrace stack events (caller[x]) causes
issues with the parser. This adds code to handle the case, but
it also assumes that the array is of type long.
Note, this is a special case used (currently) only by the ftrace
user and kernel stack records.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194358.124833639@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The code to handle the '<' and '>' ops was all in place, but
they were not in the switch statement to consider them as valid
ops.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194357.807434040@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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The handling of backslashes was broken. It would stop parsing
when encountering one. Also, '\n', '\t', '\r' and '\\' were not
converted.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194357.521974680@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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kmem_alloc ftrace event format had a string that was broken up
by two tokens. "string 1" "string 2". This patch lets the parser
be able to handle the concatenation.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194357.253818714@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Merge reason: pick up tools/perf/ changes from upstream.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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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:
firewire: sbp2: provide fallback if mgt_ORB_timeout is missing
ieee1394: add documentation entry to MAINTAINERS
ieee1394: update URLs in debugging-via-ohci1394.txt
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* branch 'tty-fixes':
tty: use the new 'flush_delayed_work()' helper to do ldisc flush
workqueue: add 'flush_delayed_work()' to run and wait for delayed work
Make flush_to_ldisc properly handle parallel calls
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git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland
* 'topic/x86-lds-nits' of git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland:
x86: linker script syntax nits
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* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
watchdog: Fix rio watchdog probe function
sparc64: Set IRQF_DISABLED on LDC channel IRQs.
sparc64: Fix D-cache flushing on swapin from SW devices.
sparc64: Fix niagara2 perf IRQ bits.
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* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
[S390] sclp_vt220 build fix
[S390] cio: change misleading console logic
[S390] call home support: fix proc handler
[S390] dasd: use idal for device characteristics
[S390] Add highgprs facility to /proc/cpuinfo
[S390] dasd: fix locking bug
[S390] tape390: Fix request queue handling in block driver
[S390] hypfs: Use subcode 6 if subcode 7 is not available
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git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* 'sh/for-2.6.32' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
sh: Fix a TRACE_IRQS_OFF typo.
sh: Optimize the setup_rt_frame() I-cache flush.
sh: Populate initial secondary CPU info from boot_cpu_data.
sh: Tidy up SMP cpuinfo.
sh: Use boot_cpu_data for FPU tests in sigcontext paths.
sh: ftrace: Fix up syscall tracepoint support.
sh: force dcache flush if dcache_dirty bit set.
sh: update die() output.
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
oprofile: warn on freeing event buffer too early
oprofile: fix race condition in event_buffer free
lockdep: Use cpu_clock() for lockstat
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf events: Update MAINTAINERS entry file patterns
perf tools: Remove static debugfs path from parse-events
perf tools: Fix the NO_64BIT build on pure 64-bit systems
perf tools: Fix const char type propagation
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: Fix missing kernel-doc notation
Revert "x86, timers: Check for pending timers after (device) interrupts"
sched: Update the clock of runqueue select_task_rq() selected
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing/filters: Fix memory leak when setting a filter
tracing: fix trace_vprintk call
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86/paravirt: Use normal calling sequences for irq enable/disable
x86: fix kernel panic on 32 bits when profiling
x86: Fix Suspend to RAM freeze on Acer Aspire 1511Lmi laptop
x86, vmi: Mark VMI deprecated and schedule it for removal
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The linker scripts grew some use of weirdly wrong linker script syntax.
It happens to work, but it's not what the syntax is documented to be.
Clean it up to use the official syntax.
Signed-off-by: Roland McGrath <roland@redhat.com>
CC: Ian Lance Taylor <iant@google.com>
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The Unit_Characteristics entry of an SBP-2 unit directory is not
mandatory as far as I can tell. If it is missing, we would probably
fail to log in into the target because firewire-sbp2 would not wait for
status after it sent the login request.
The fix moves the cleanup of tgt->mgt_orb_timeout into a place where it
is executed exactly once before login, rather than 0..n times depending
on the target's config ROM. With targets with one or more
Unit_Characteristics entries, the result is the same as before.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
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set_cmdline_ftrace is a better match against what does this function:
apply a tracer name from the kernel command line.
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
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We are using strncpy in the wrong way to copy the ftrace_graph_filter
boot param because we pass the buffer size instead of the max string
size it can contain (buffer size - 1). The end result might not be
NULL terminated as we are abusing the max string size.
Lets use strlcpy() instead.
Reported-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
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This way all flush_to_ldisc work is always done through the workqueues,
and we thus have a single point of serialization.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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It basically turns a delayed work into an immediate work, and then waits
for it to finish.
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Fix this build error:
next-20091013 randconfig build on s390x build breaks with
drivers/s390/built-in.o:(.data+0x3354): undefined reference to `sclp_vt220_pm_event_fn'
Reported-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <michael.holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Use cio_is_console() in io_subchannel_probe to indicate that the
special handling is console specific. As long as there is no other
subchannel for which this might be true, it is misleading to speak
of "early devices". Should more of these devices be introduced,
a cleanup of all console special handling is in order anyway.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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8d65af78 "sysctl: remove "struct file *" argument of ->proc_handler"
removed the struct file argument from all proc_handlers but didn't
change the call home proc handler (or call home was merged later).
So fix this now.
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Hans-Joachim Picht <hans@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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If the rdc_buffer is above 2G we need indirect addresssing so we have
to use an idaw to give the rdc_buffer to the ccw.
If the rdc_buffer is under 2G nothing changes.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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This patch makes the hwcap bit for the high gprs feature to be visible
in /proc/cpuinfo.
Signed-off-by: Andreas Krebbel <Andreas.Krebbel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Replace spin_lock with spin_lock_irqsave in dasd_eckd_restore_device.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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When setting a channel attached tape online under Linux 2.6.31, the
"vol_id" process from udev hangs in sync_page():
2 sync_page+144 [0x1dfaac]
3 __wait_on_bit_lock+194 [0x58c23e]
4 __lock_page+116 [0x1df9dc]
5 truncate_inode_pages_range+728 [0x1ed7cc]
6 __blkdev_put+244 [0x25f738]
7 __fput+300 [0x229c4c]
8 filp_close+122 [0x225a3a]
The reason for that is an error in the request queue handling. It can
happen that we fetch a request, but do not process it further because
the number of queued requests exceeds TAPEBLOCK_MIN_REQUEUE.
To fix this, we should call blk_peek_request() instead of
blk_fetch_request() in the while condition and fetch the request in
the loop body afterwards.
This bug was introduced with the patch "block: implement and enforce
request peek/start/fetch" (9934c8c04561413609d2bc38c6b9f268cba774a4)
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Hypfs never worked on systems that only provide D204 subcode 6.
In these cases we nevertheless used subcode 7. With this fix, we
use subcode 6, if it is available and the system does not provide
subcode 7.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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