This patch adds two files to the debugfs system:
/debugfs/tracing/available_filter_functions
and
/debugfs/tracing/set_ftrace_filter
The available_filter_functions lists all functions that has been
recorded by the ftraced that has called the ftrace_record_ip function.
This is to allow users to see what functions have been converted
to nops and can be enabled for tracing.
To enable functions, simply echo the names (whitespace delimited)
into set_ftrace_filter. Simple wildcards are also allowed.
echo 'scheduler' > /debugfs/tracing/set_ftrace_filter
Will have only the scheduler be activated when tracing is enabled.
echo 'sched_*' > /debugfs/tracing/set_ftrace_filter
Will have only the functions starting with 'sched_' be activated.
echo '*lock' > /debugfs/tracing/set_ftrace_filter
Will have only functions ending with 'lock' be activated.
echo '*lock*' > /debugfs/tracing/set_ftrace_filter
Will have only functions with 'lock' in its name be activated.
Note: 'sched*lock' will not work. The only wildcards that are
allowed is an asterisk and the beginning and or end of the string
passed in.
Multiple names can be passed in with whitespace delimited:
echo 'scheduler *lock *acpi*' > /debugfs/tracing/set_ftrace_filter
is also the same as:
echo 'scheduler' > /debugfs/tracing/set_ftrace_filter
echo '*lock' >> /debugfs/tracing/set_ftrace_filter
echo '*acpi*' >> /debugfs/tracing/set_ftrace_filter
Appending does just that. It appends to the list.
To disable all filters simply echo an empty line in:
echo > /debugfs/tracing/set_ftrace_filter
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch replaces the indirect call to the mcount function
pointer with a direct call that will be patched by the
dynamic ftrace routines.
On boot up, the mcount function calls the ftace_stub function.
When the dynamic ftrace code is initialized, the ftrace_stub
is replaced with a call to the ftrace_record_ip, which records
the instruction pointers of the locations that call it.
Later, the ftraced daemon will call kstop_machine and patch all
the locations to nops.
When a ftrace is enabled, the original calls to mcount will now
be set top call ftrace_caller, which will do a direct call
to the registered ftrace function. This direct call is also patched
when the function that should be called is updated.
All patching is performed by a kstop_machine routine to prevent any
type of race conditions that is associated with modifying code
on the fly.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch moves the memory management of the ftrace
records out of the arch code and into the generic code
making the arch code simpler.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch patches the call to mcount with nops instead
of a jmp over the mcount call.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds back the sysctl ftrace_enabled. This time it is
defaulted to on, if DYNAMIC_FTRACE is configured. When ftrace_enabled
is disabled, the ftrace function is set to the stub return.
If DYNAMIC_FTRACE is also configured, on ftrace_enabled = 0,
the registered ftrace functions will all be set to jmps, but no more
new calls to ftrace recording (used to find the ftrace calling sites)
will be called.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds a feature to dynamically replace the ftrace code
with the jmps to allow a kernel with ftrace configured to run
as fast as it can without it configured.
The way this works, is on bootup (if ftrace is enabled), a ftrace
function is registered to record the instruction pointer of all
places that call the function.
Later, if there's still any code to patch, a kthread is awoken
(rate limited to at most once a second) that performs a stop_machine,
and replaces all the code that was called with a jmp over the call
to ftrace. It only replaces what was found the previous time. Typically
the system reaches equilibrium quickly after bootup and there's no code
patching needed at all.
e.g.
call ftrace /* 5 bytes */
is replaced with
jmp 3f /* jmp is 2 bytes and we jump 3 forward */
3:
When we want to enable ftrace for function tracing, the IP recording
is removed, and stop_machine is called again to replace all the locations
of that were recorded back to the call of ftrace. When it is disabled,
we replace the code back to the jmp.
Allocation is done by the kthread. If the ftrace recording function is
called, and we don't have any record slots available, then we simply
skip that call. Once a second a new page (if needed) is allocated for
recording new ftrace function calls. A large batch is allocated at
boot up to get most of the calls there.
Because we do this via stop_machine, we don't have to worry about another
CPU executing a ftrace call as we modify it. But we do need to worry
about NMI's so all functions that might be called via nmi must be
annotated with notrace_nmi. When this code is configured in, the NMI code
will not call notrace.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Add preempt off timings. A lot of kernel core code is taken from the RT patch
latency trace that was written by Ingo Molnar.
This adds "preemptoff" and "preemptirqsoff" to /debugfs/tracing/available_tracers
Now instead of just tracing irqs off, preemption off can be selected
to be recorded.
When this is selected, it shares the same files as irqs off timings.
One can either trace preemption off, irqs off, or one or the other off.
By echoing "preemptoff" into /debugfs/tracing/current_tracer, recording
of preempt off only is performed. "irqsoff" will only record the time
irqs are disabled, but "preemptirqsoff" will take the total time irqs
or preemption are disabled. Runtime switching of these options is now
supported by simpling echoing in the appropriate trace name into
/debugfs/tracing/current_tracer.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds the latency tracer infrastructure. This patch
does not add anything that will select and turn it on, but will
be used by later patches.
If it were to be compiled, it would add the following files
to the debugfs:
The root tracing directory:
/debugfs/tracing/
This patch also adds the following files:
available_tracers
list of available tracers. Currently no tracers are
available. Looking into this file only shows
"none" which is used to unregister all tracers.
current_tracer
The trace that is currently active. Empty on start up.
To switch to a tracer simply echo one of the tracers that
are listed in available_tracers:
example: (used with later patches)
echo function > /debugfs/tracing/current_tracer
To disable the tracer:
echo disable > /debugfs/tracing/current_tracer
tracing_enabled
echoing "1" into this file starts the ftrace function tracing
(if sysctl kernel.ftrace_enabled=1)
echoing "0" turns it off.
latency_trace
This file is readonly and holds the result of the trace.
trace
This file outputs a easier to read version of the trace.
iter_ctrl
Controls the way the output of traces look.
So far there's two controls:
echoing in "symonly" will only show the kallsyms variables
without the addresses (if kallsyms was configured)
echoing in "verbose" will change the output to show
a lot more data, but not very easy to understand by
humans.
echoing in "nosymonly" turns off symonly.
echoing in "noverbose" turns off verbose.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
If CONFIG_FTRACE is selected and /proc/sys/kernel/ftrace_enabled is
set to a non-zero value the ftrace routine will be called everytime
we enter a kernel function that is not marked with the "notrace"
attribute.
The ftrace routine will then call a registered function if a function
happens to be registered.
[ This code has been highly hacked by Steven Rostedt and Ingo Molnar,
so don't blame Arnaldo for all of this ;-) ]
Update:
It is now possible to register more than one ftrace function.
If only one ftrace function is registered, that will be the
function that ftrace calls directly. If more than one function
is registered, then ftrace will call a function that will loop
through the functions to call.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Mark with "notrace" functions in core code that should not be
traced. The "notrace" attribute will prevent gcc from adding
a call to ftrace on the annotated funtions.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Add the notrace annotations to the vsyscall functions - there we are
not in kernel context yet, so the tracer function cannot (and must not)
be called.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
notrace signals that a function should not be traced. Most of the
time this is used by tracers to annotate code that cannot be
traced - it's in a volatile state (such as in user vdso context
or NMI context) or it's in the tracer internals.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The tracer may need to call preempt_enable and disable functions
for time keeping and such. The trace gets ugly when we see these
functions show up for all traces. To make the output cleaner
this patch adds preempt_enable_notrace and preempt_disable_notrace
to be used by tracer (and debugging) functions.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The tracer wants to be able to convert the state number
into a user visible character. This patch pulls that conversion
string out the scheduler into the header. This way if it were to
ever change, other parts of the kernel will know.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
add 3 lightweight callbacks to the tracer backend.
zero impact if tracing is turned off.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
CIFS currently allows you to change the ownership of a file, but unless
unix extensions are enabled this change is not passed off to the server.
Have CIFS silently ignore ownership changes that can't be persistently
stored on the server unless the "setuids" option is explicitly
specified.
We could return an error here (-EOPNOTSUPP or something), but this is
how most disk-based windows filesystems on behave on Linux (e.g. VFAT,
NTFS, etc). With cifsacl support and proper Windows to Unix idmapping
support, we may be able to do this more properly in the future.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When CIFS creates a new inode on a mount without unix extensions, it
temporarily assigns the mode that was passed to it in the create/mkdir
call. Eventually, when the inode is revalidated, it changes to have the
file_mode or dir_mode for the mount. This is confusing to users who
expect that the mode shouldn't change this way. It's also problematic
since only the mode is treated this way, not the uid or gid. Suppose you
have a CIFS mount that's mounted with:
uid=0,gid=0,file_mode=0666,dir_mode=0777
...if an unprivileged user comes along and does this on the mount:
mkdir -m 0700 foo
touch foo/bar
...there is a period of time where the touch will fail, since the dir
will initially be owned by root and have mode 0700. If the user waits
long enough, then "foo" will be revalidated and will get the correct
dir_mode permissions.
This patch changes cifs_mkdir and cifs_create to not overwrite the
mode found by the initial cifs_get_inode_info call after the inode is
created on the server. Legacy behavior can be reenabled with the
new "dynperm" mount option.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When mounting a share with posix extensions disabled,
cifs_get_inode_info turns off all the write bits in the mode for regular
files if ATTR_READONLY is set. Directories and other inode types,
however, can also have ATTR_READONLY set, but the mode gives no
indication of this.
This patch makes this apply to other inode types besides regular files.
It also cleans up how modes are set in cifs_get_inode_info for both the
"normal" and "dynperm" cases.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
IB/mad: Fix kernel crash when .process_mad() returns SUCCESS|CONSUMED
IPoIB: Test for NULL broadcast object in ipiob_mcast_join_finish()
MAINTAINERS: Add cxgb3 and iw_cxgb3 NIC and iWARP driver entries
IB/mlx4: Fix creation of kernel QP with max number of send s/g entries
IB/mthca: Fix max_sge value returned by query_device
RDMA/cxgb3: Fix uninitialized variable warning in iwch_post_send()
IB/mlx4: Fix uninitialized-var warning in mlx4_ib_post_send()
IB/ipath: Fix UC receive completion opcode for RDMA WRITE with immediate
IB/ipath: Fix printk format for ipath_sdma_status
If a low-level driver returns IB_MAD_RESULT_SUCCESS | IB_MAD_RESULT_CONSUMED,
handle_outgoing_dr_smp() doesn't clean up properly. The fix is to
kfree the local data and break, rather than falling through. This was
observed with the ipath driver, but could happen with any driver.
This fixes <https://bugs.openfabrics.org/show_bug.cgi?id=1027>.
Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
CR4 manipulation is not protected against interrupts and preemption,
but KVM uses smp_function_call to manipulate the X86_CR4_VMXE bit
either from the CPU hotplug code or from the kvm_init call.
We need to protect the CR4 manipulation from both interrupts and
preemption.
Original bug report: http://lkml.org/lkml/2008/5/7/48
Bugzilla entry: http://bugzilla.kernel.org/show_bug.cgi?id=10642
This is not a regression from 2.6.25, it's a long standing and hard to
trigger bug.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Not sure how this snuck upstream, but it really doesn't belong there. We
don't need a KERN_ERR printk in the suspend path to know what's going on (at
least not anymore).
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
[POWERPC] iSeries: Remove unused mail address
[POWERPC] mpic: Fix use of uninitialized variable
[POWERPC] Add kernstart_addr to list of allowed symbols in prom_init
[POWERPC] Fix __set_fixmap() for STRICT_MM_TYPECHECKS
[POWERPC] PS3: Fix memory hotplug
* 'for-linus' of git://oss.sgi.com:8090/xfs/xfs-2.6:
[XFS] Fix memory corruption with small buffer reads
[XFS] Fix inode list allocation size in writeback.
[XFS] Don't allow memory reclaim to wait on the filesystem in inode
[XFS] Fix fsync() b0rkage.
[XFS] Include linux/random.h in all builds, not just debug builds.
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
stop_machine: make stop_machine_run more virtualization friendly
doc: add a chapter about trylock functions [Bug 9011]
modules: proper cleanup of kobject without CONFIG_SYSFS
module loading ELF handling: use SELFMAG instead of numeric constant
drivers/video/aty/atyfb_base.c:3359:26: warning: Using plain integer as NULL pointer
drivers/video/aty/radeon_base.c:2280:32: warning: Using plain integer as NULL pointer
drivers/video/matrox/matroxfb_base.h:203:25: warning: Using plain integer as NULL pointer
drivers/video/matrox/matroxfb_base.h:203:25: warning: Using plain integer as NULL pointer
drivers/video/sis/sis_main.c:5790:44: warning: Using plain integer as NULL pointer
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/scsi/aha152x.c:3585:60: warning: Using plain integer as NULL pointer
drivers/scsi/aha152x.c:3845:56: warning: Using plain integer as NULL pointer
drivers/scsi/qla1280.c:2814:37: warning: Using plain integer as NULL pointer
drivers/scsi/atp870u.c:750:47: warning: Using plain integer as NULL pointer
drivers/scsi/3w-9xxx.c:1281:36: warning: Using plain integer as NULL pointer
drivers/scsi/3w-9xxx.c:1293:36: warning: Using plain integer as NULL pointer
drivers/scsi/3w-9xxx.c:1301:35: warning: Using plain integer as NULL pointer
drivers/scsi/hptiop.c:447:10: warning: Using plain integer as NULL pointer
drivers/scsi/hptiop.c:457:10: warning: Using plain integer as NULL pointer
drivers/scsi/hptiop.c:479:24: warning: Using plain integer as NULL pointer
drivers/scsi/hptiop.c:483:22: warning: Using plain integer as NULL pointer
drivers/scsi/hptiop.c:1213:23: warning: Using plain integer as NULL pointer
drivers/scsi/hptiop.c:1214:23: warning: Using plain integer as NULL pointer
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/isdn/hysdn/hycapi.c:465:42: warning: Using plain integer as NULL pointer
drivers/isdn/hysdn/hycapi.c:467:44: warning: Using plain integer as NULL pointer
drivers/isdn/hysdn/hycapi.c:469:42: warning: Using plain integer as NULL pointer
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/acpi/dispatcher/dsmethod.c:568:50: warning: Using plain integer as NULL pointer
drivers/acpi/executer/exmutex.c:329:30: warning: Using plain integer as NULL pointer
drivers/acpi/executer/exmutex.c:466:31: warning: Using plain integer as NULL pointer
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
OMAP has two include loops in its header files:
asm-arm/hardware.h <- asm-arm/arch-omap/io.h <-
asm-arm/arch-omap/hardware.h <- asm-arm/hardware.h
asm-arm/arch-omap/board-palmte.h <-
asm-arm/arch-omap/hardware.h <- asm-arm/hardware.h <-
asm-arm/arch-omap/gpio.h <- asm-arm/arch-omap/board-palmte.h
Circular include dependencies are dangerous since they can result in
inconsistent definitions being provided to other code, especially if
'#ifndef' constructs are used.
Solve these by removing the offending includes, and add additional
includes where necessary.
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
For the simple read_cpuid() macro case the variable processor_id has
no definition on use of the macro. Add an extern for it. Move all the
processor ID macros into the #ifndef __ASSEMBLEY__ block.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Export the AT91 clock functions for the AT91X40. Some external code common
to all AT91 family parts relys on this, like the gpio and serial support.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The non-MMU case also needs the type definition of pgtable_t.
So move it out of a CONFIG_MMU conditional section.
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Jeremy's gcc 3.4 seems to be unable to inline a 8 byte memcpy. But the
vdso doesn't support external references. Copy the structure members
of struct timezone explicitely instead.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
While I realize that the function isn't currently being used, I still
think an obvious mistake like this should be corrected.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
A check for unmapped apic was added before reading maxlvt but the early
read of maxlvt wasn't removed.
Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
When the TSC calibration fails then TSC is still used in
sched_clock(). Disable it completely in that case.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
tsc_enabled is set to 0 from the command line switch "notsc" and from
the mark_tsc_unstable code. Seperate those functionalities and replace
tsc_enable with tsc_disable. This makes also the native_sched_clock()
decision when to use TSC understandable.
Preparatory patch to solve the sched_clock() issue on 32 bit.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When the TSC is calibrated against the PIT due to the nonavailability
of PMTIMER/HPET or due to SMI interference then the setup of the per
CPU cyc2ns variables is skipped. This is unlikely to happen but it
would definitely render sched_clock() unusable.
This was introduced with commit 53d517cdba
x86: scale cyc_2_nsec according to CPU frequency
Update the per CPU cyc2ns variables in all exit pathes of tsc_calibrate.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
