The tracepoint sample code was used to teach developers how to
create their own tracepoints. But now the trace_events have been
added as a higher level that is used directly by developers today.
Only the trace_event code should use the tracepoint interface
directly and no new tracepoints should be added.
Besides, the example had a race condition with the use of the
->d_name.name dentry field, as pointed out by Al Viro.
Best just to remove the code so it wont be used by other developers.
Link: http://lkml.kernel.org/r/20130123225523.GY4939@ZenIV.linux.org.uk
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
. perf build-id cache now can show DSOs present in a perf.data file that are
not in the cache, to integrate with build-id servers being put in place by
organizations such as Fedora.
. perf buildid-list -i an-elf-file-instead-of-a-perf.data is back showing its
build-id.
. No need to do feature checks when doing a 'make tags'
. Fix some 'perf test' errors and make them use the tracepoint evsel constructor.
. perf top now shares more of the evsel config/creation routines with 'record',
paving the way for further integration like 'top' snapshots, etc.
. perf top now supports DWARF callchains.
. perf evlist decodes sample_type and read_format, helping diagnose problems.
. Fix mmap limitations on 32-bit, fix from David Miller.
. perf diff fixes from Jiri Olsa.
. Ignore ABS symbols when loading data maps, fix from Namhyung Kim
. Hists improvements from Namhyung Kim
. Don't check configuration on make clean, from Namhyung Kim
. Fix dso__fprintf() print statement, from Stephane Eranian.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dan's smatch found a compare bug with the result of the
trace_test_and_set_recursion() and comparing to less than
zero. If the function fails, it returns -1, but was saved in
an unsigned int, which will never be less than zero and will
ignore the result of the test if a recursion did happen.
Luckily this is the last of the recursion tests, as the
infrastructure of ftrace would catch recursions before it
got here, except for some few exceptions.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull tracing updates from Steve Rostedt.
This commit:
tracing: Remove the extra 4 bytes of padding in events
changes the ABI. All involved parties seem to agree that it's safe to
do now, but the devil is in the details ...
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull more USB fixes from Greg Kroah-Hartman:
"Here are some more USB fixes for the 3.8-rc4 tree.
Some gadget driver fixes, and finally resolved the ehci-mxc driver
build issues (it's just some code moving around and being deleted)."
* tag 'usb-3.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: EHCI: fix build error in ehci-mxc
USB: EHCI: add a name for the platform-private field
USB: EHCI: fix incorrect configuration test
USB: EHCI: Move definition of EHCI_STATS to ehci.h
USB: UHCI: fix IRQ race during initialization
usb: gadget: FunctionFS: Fix missing braces in parse_opts
usb: dwc3: gadget: fix ep->maxburst for ep0
ARM: i.MX clock: Change the connection-id for fsl-usb2-udc
usb: gadget: fsl_mxc_udc: replace MX35_IO_ADDRESS to ioremap
usb: gadget: fsl-mxc-udc: replace cpu_is_xxx() with platform_device_id
usb: musb: cppi_dma: drop '__init' annotation
Pull drivers/misc fix from Greg Kroah-Hartman:
"Here is a single revert for the ti-st misc driver, fixing problem that
was introduced in 3.7-rc1 that has been bothering people."
* tag 'char-misc-3.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
Revert "drivers/misc/ti-st: remove gpio handling"
Pull a TTY maintainer patch from Greg Kroah-Hartman:
"Just a MAINTAINERS update, now that Alan has left for a bit, I'll
continue to watch over the serial drivers."
* tag 'tty-3.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
MAINTAINERS: Someone needs to watch over the serial drivers
Pull media fixes from Mauro Carvalho Chehab:
- gspca: add needed delay for I2C traffic for sonixb/sonixj cameras
- gspca: add one missing Kinect USB ID
- usbvideo: some regression fixes
- omap3isp: fix some build issues
- videobuf2: fix video output handling
- exynos s5p/m5mols: a few regression fixes.
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] uvcvideo: Set error_idx properly for S_EXT_CTRLS failures
[media] uvcvideo: Cleanup leftovers of partial revert
[media] uvcvideo: Return -EACCES when trying to set a read-only control
[media] omap3isp: Don't include <plat/cpu.h>
[media] s5p-mfc: Fix interrupt error handling routine
[media] s5p-fimc: Fix return value of __fimc_md_create_flite_source_links()
[media] m5mols: Fix typo in get_fmt callback
[media] v4l: vb2: Set data_offset to 0 for single-plane output buffers
[media] [FOR,v3.8] omap3isp: Don't include deleted OMAP plat/ header files
[media] gspca_sonixj: Add a small delay after i2c_w1
[media] gspca_sonixb: Properly wait between i2c writes
[media] gspca_kinect: add Kinect for Windows USB id
Pull m68k fixes from Geert Uytterhoeven:
"The asm-generic changeset has been ack'ed by Arnd."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
m68k: Wire up finit_module
asm-generic/dma-mapping-broken.h: Provide dma_alloc_attrs()/dma_free_attrs()
m68k: Provide dma_alloc_attrs()/dma_free_attrs()
Pull arm64 fixes from Catalin Marinas:
- ELF coredump fix (more registers dumped than what user space expects)
- SUBARCH name generation (s/aarch64/arm64/)
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
arm64: makefile: fix uname munging when setting ARCH on native machine
arm64: elf: fix core dumping to match what glibc expects
This patch (as1643b) fixes a build error in ehci-hcd when compiling for
ARM with allmodconfig:
drivers/usb/host/ehci-hcd.c:1285:0: warning: "PLATFORM_DRIVER" redefined [enabled by default]
drivers/usb/host/ehci-hcd.c:1255:0: note: this is the location of the previous definition
drivers/usb/host/ehci-mxc.c:280:31: warning: 'ehci_mxc_driver' defined but not used [-Wunused-variable]
drivers/usb/host/ehci-hcd.c:1285:0: warning: "PLATFORM_DRIVER" redefined [enabled by default]
drivers/usb/host/ehci-hcd.c:1255:0: note: this is the location of the previous definition
The fix is to convert ehci-mxc over to the new "ehci-hcd is a library"
scheme so that it can coexist peacefully with the ehci-platform
driver. As part of the conversion the ehci_mxc_priv data structure,
which was allocated dynamically, is now placed where it belongs: in
the private area at the end of struct ehci_hcd.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull sound fixes from Takashi Iwai:
"Only a few small HD-audio fixes:
- Addition of new Conexant codec IDs
- Two one-liners to add fixups for Realtek codecs
- A last-minute regression fix for auto-mute with power-saving mode
(regressed since 3.8-rc1)"
* tag 'sound-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda - Fix inconsistent pin states after resume
ALSA: hda - Add Conexant CX20755/20756/20757 codec IDs
ALSA: hda - Add fixup for Acer AO725 laptop
ALSA: hda - Fix mute led for another HP machine
The commit [26a6cb6c: ALSA: hda - Implement a poll loop for jacks as a
module parameter] introduced the polling jack detection code, but it
also moved the call of snd_hda_jack_set_dirty_all() in the resume path
after resume/init ops call. This caused a regression when the jack
state has been changed during power-down (e.g. in the power save
mode). Since the driver doesn't probe the new jack state but keeps
using the cached value due to no dirty flag, the pin state remains
also as if the jack is still plugged.
The fix is simply moving snd_hda_jack_set_dirty_all() to the original
position.
Reported-by: Manolo Díaz <diaz.manolo@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
ring_buffer.c use to require declarations from trace.h, but
these have moved to the generic header files. There's nothing
in trace.h that ring_buffer.c requires.
There's some headers that trace.h included that ring_buffer.c
needs, but it's best that it includes them directly, and not
include trace.h.
Also, some things may use ring_buffer.c without having tracing
configured. This removes the dependency that may come in the
future.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Using context bit recursion checking, we can help increase the
performance of the ring buffer.
Before this patch:
# echo function > /debug/tracing/current_tracer
# for i in `seq 10`; do ./hackbench 50; done
Time: 10.285
Time: 10.407
Time: 10.243
Time: 10.372
Time: 10.380
Time: 10.198
Time: 10.272
Time: 10.354
Time: 10.248
Time: 10.253
(average: 10.3012)
Now we have:
# echo function > /debug/tracing/current_tracer
# for i in `seq 10`; do ./hackbench 50; done
Time: 9.712
Time: 9.824
Time: 9.861
Time: 9.827
Time: 9.962
Time: 9.905
Time: 9.886
Time: 10.088
Time: 9.861
Time: 9.834
(average: 9.876)
a 4% savings!
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The function tracer had two different versions of function tracing.
The disabling of irqs version and the preempt disable version.
As function tracing in very intrusive and can cause nasty recursion
issues, it has its own recursion protection. But the old method to
do this was a flat layer. If it detected that a recursion was happening
then it would just return without recording.
This made the preempt version (much faster than the irq disabling one)
not very useful, because if an interrupt were to occur after the
recursion flag was set, the interrupt would not be traced at all,
because every function that was traced would think it recursed on
itself (due to the context it preempted setting the recursive flag).
Now that we have a recursion flag for every context level, we
no longer need to worry about that. We can disable preemption,
set the current context recursion check bit, and go on. If an
interrupt were to come along, it would check its own context bit
and happily continue to trace.
As the preempt version is faster than the irq disable version,
there's no more reason to keep the preempt version around.
And the irq disable version still had an issue with missing
out on tracing NMI code.
Remove the irq disable function tracer version and have the
preempt disable version be the default (and only version).
Before this patch we had from running:
# echo function > /debug/tracing/current_tracer
# for i in `seq 10`; do ./hackbench 50; done
Time: 12.028
Time: 11.945
Time: 11.925
Time: 11.964
Time: 12.002
Time: 11.910
Time: 11.944
Time: 11.929
Time: 11.941
Time: 11.924
(average: 11.9512)
Now we have:
# echo function > /debug/tracing/current_tracer
# for i in `seq 10`; do ./hackbench 50; done
Time: 10.285
Time: 10.407
Time: 10.243
Time: 10.372
Time: 10.380
Time: 10.198
Time: 10.272
Time: 10.354
Time: 10.248
Time: 10.253
(average: 10.3012)
a 13.8% savings!
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When function tracing occurs, the following steps are made:
If arch does not support a ftrace feature:
call internal function (uses INTERNAL bits) which calls...
If callback is registered to the "global" list, the list
function is called and recursion checks the GLOBAL bits.
then this function calls...
The function callback, which can use the FTRACE bits to
check for recursion.
Now if the arch does not suppport a feature, and it calls
the global list function which calls the ftrace callback
all three of these steps will do a recursion protection.
There's no reason to do one if the previous caller already
did. The recursion that we are protecting against will
go through the same steps again.
To prevent the multiple recursion checks, if a recursion
bit is set that is higher than the MAX bit of the current
check, then we know that the check was made by the previous
caller, and we can skip the current check.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Currently for recursion checking in the function tracer, ftrace
tests a task_struct bit to determine if the function tracer had
recursed or not. If it has, then it will will return without going
further.
But this leads to races. If an interrupt came in after the bit
was set, the functions being traced would see that bit set and
think that the function tracer recursed on itself, and would return.
Instead add a bit for each context (normal, softirq, irq and nmi).
A check of which context the task is in is made before testing the
associated bit. Now if an interrupt preempts the function tracer
after the previous context has been set, the interrupt functions
can still be traced.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Steven Rostedt
Josh Triplett
Ingo Molnar
Frederic Weisbecker
Linus Torvalds
Greg Kroah-Hartman
Alan Stern
Alan Cox
Takashi Iwai