4a88d44ab1 ("tracing: Remove mentioning of legacy latency_trace file
from documentation") changed a sentence to refer to only one file
instead of two, but the sentence still uses "they". Fix it.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Pull char / misc patches from Greg KH:
"Here's the big char/misc driver update for 3.20-rc1.
Lots of little things in here, all described in the changelog.
Nothing major or unusual, except maybe the binder selinux stuff, which
was all acked by the proper selinux people and they thought it best to
come through this tree.
All of this has been in linux-next with no reported issues for a while"
* tag 'char-misc-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (90 commits)
coresight: fix function etm_writel_cp14() parameter order
coresight-etm: remove check for unknown Kconfig macro
coresight: fixing CPU hwid lookup in device tree
coresight: remove the unnecessary function coresight_is_bit_set()
coresight: fix the debug AMBA bus name
coresight: remove the extra spaces
coresight: fix the link between orphan connection and newly added device
coresight: remove the unnecessary replicator property
coresight: fix the replicator subtype value
pdfdocs: Fix 'make pdfdocs' failure for 'uio-howto.tmpl'
mcb: Fix error path of mcb_pci_probe
virtio/console: verify device has config space
ti-st: clean up data types (fix harmless memory corruption)
mei: me: release hw from reset only during the reset flow
mei: mask interrupt set bit on clean reset bit
extcon: max77693: Constify struct regmap_config
extcon: adc-jack: Release IIO channel on driver remove
extcon: Remove duplicated include from extcon-class.c
Drivers: hv: vmbus: hv_process_timer_expiration() can be static
Drivers: hv: vmbus: serialize Offer and Rescind offer
...
The command `echo > set_ftrace_pid` should be used to clean the filter quietly.
because the command `echo -1 > set_ftrace_pid` will output the following:
"bash: echo: write error: Invalid argument".
so update the file Documentation/trace/ftrace.txt.
Signed-off-by: Wang Long <long.wanglong@huawei.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Pull char/misc driver updates from Greg KH:
"Here's the big char/misc driver update for 3.19-rc1
Lots of little things all over the place in different drivers, and a
new subsystem, "coresight" has been added. Full details are in the
shortlog"
* tag 'char-misc-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (73 commits)
parport: parport_pc, do not remove parent devices early
spmi: Remove shutdown/suspend/resume kernel-doc
carma-fpga-program: drop videobuf dependency
carma-fpga: drop videobuf dependency
carma-fpga-program.c: fix compile errors
i8k: Fix temperature bug handling in i8k_get_temp()
cxl: Name interrupts in /proc/interrupt
CXL: Return error to PSL if IRQ demultiplexing fails & print clearer warning
coresight-replicator: remove .owner field for driver
coresight: fixed comments in coresight.h
coresight: fix typo in comment in coresight-priv.h
coresight: bindings for coresight drivers
coresight: Adding ABI documentation
w1: support auto-load of w1_bq27000 module.
w1: avoid potential u16 overflow
cn: verify msg->len before making callback
mei: export fw status registers through sysfs
mei: read and print all six FW status registers
mei: txe: add cherrytrail device id
mei: kill cached host and me csr values
...
Currently, function graph tracer prints "!" or "+" just before
function execution time to signal a function overhead, depending
on the time. And some tracers tracing latency also print "!" or
"+" just after time to signal overhead, depending on the interval
between events. Even it is usually enough to do that, we sometimes
need to signal for bigger execution time than 100 micro seconds.
For example, I used function graph tracer to detect if there is
any case that exit_mm() takes too much time. I did following steps
in /sys/kernel/debug/tracing. It was easier to detect very large
excution time with patched kernel than with original kernel.
$ echo exit_mm > set_graph_function
$ echo function_graph > current_tracer
$ echo > trace
$ cat trace_pipe > $LOGFILE
... (do something and terminate logging)
$ grep "\\$" $LOGFILE
3) $ 22082032 us | } /* kernel_map_pages */
3) $ 22082040 us | } /* free_pages_prepare */
3) $ 22082113 us | } /* free_hot_cold_page */
3) $ 22083455 us | } /* free_hot_cold_page_list */
3) $ 22083895 us | } /* release_pages */
3) $ 22177873 us | } /* free_pages_and_swap_cache */
3) $ 22178929 us | } /* unmap_single_vma */
3) $ 22198885 us | } /* unmap_vmas */
3) $ 22206949 us | } /* exit_mmap */
3) $ 22207659 us | } /* mmput */
3) $ 22207793 us | } /* exit_mm */
And then, it was easy to find out that a schedule-out occured by
sub_preempt_count() within kernel_map_pages().
To detect very large function exection time caused by either problematic
function implementation or scheduling issues, this patch can be useful.
Link: http://lkml.kernel.org/r/1416789259-24038-1-git-send-email-byungchul.park@lge.com
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Introduce FTRACE_OPS_FL_IPMODIFY to avoid conflict among
ftrace users who may modify regs->ip to change the execution
path. If two or more users modify the regs->ip on the same
function entry, one of them will be broken. So they must add
IPMODIFY flag and make sure that ftrace_set_filter_ip() succeeds.
Note that ftrace doesn't allow ftrace_ops which has IPMODIFY
flag to have notrace hash, and the ftrace_ops must have a
filter hash (so that the ftrace_ops can hook only specific
entries), because it strongly depends on the address and
must be allowed for only few selected functions.
Link: http://lkml.kernel.org/r/20141121102516.11844.27829.stgit@localhost.localdomain
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Petr Mladek <pmladek@suse.cz>
Cc: Vojtech Pavlik <vojtech@suse.cz>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
[ fixed up some of the comments ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Documentation containing an explanation on what the framework
provides and the drivers working with it. A minimal example
on how to use the functionality is also provided.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Until now, the reporting from trace-vmscan-postprocess.pl is not very
useful because we cannot directly use this script for checking the
file/anon ratio of scanning. This patch aims to report respectively the
number of file/anon pages which were scanned/reclaimed by kswapd or
direct-reclaim. Sample output is usually something like the following.
Summary
Direct reclaims: 8823
Direct reclaim pages scanned: 2438797
Direct reclaim file pages scanned: 1315200
Direct reclaim anon pages scanned: 1123597
Direct reclaim pages reclaimed: 446139
Direct reclaim file pages reclaimed: 378668
Direct reclaim anon pages reclaimed: 67471
Direct reclaim write file sync I/O: 0
Direct reclaim write anon sync I/O: 0
Direct reclaim write file async I/O: 0
Direct reclaim write anon async I/O: 4240
Wake kswapd requests: 122310
Time stalled direct reclaim: 13.78 seconds
Kswapd wakeups: 25817
Kswapd pages scanned: 170779115
Kswapd file pages scanned: 162725123
Kswapd anon pages scanned: 8053992
Kswapd pages reclaimed: 129065738
Kswapd file pages reclaimed: 128500930
Kswapd anon pages reclaimed: 564808
Kswapd reclaim write file sync I/O: 0
Kswapd reclaim write anon sync I/O: 0
Kswapd reclaim write file async I/O: 36
Kswapd reclaim write anon async I/O: 730730
Time kswapd awake: 1015.50 seconds
Signed-off-by: Chen Yucong <slaoub@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull scheduler updates from Ingo Molnar:
- Move the nohz kick code out of the scheduler tick to a dedicated IPI,
from Frederic Weisbecker.
This necessiated quite some background infrastructure rework,
including:
* Clean up some irq-work internals
* Implement remote irq-work
* Implement nohz kick on top of remote irq-work
* Move full dynticks timer enqueue notification to new kick
* Move multi-task notification to new kick
* Remove unecessary barriers on multi-task notification
- Remove proliferation of wait_on_bit() action functions and allow
wait_on_bit_action() functions to support a timeout. (Neil Brown)
- Another round of sched/numa improvements, cleanups and fixes. (Rik
van Riel)
- Implement fast idling of CPUs when the system is partially loaded,
for better scalability. (Tim Chen)
- Restructure and fix the CPU hotplug handling code that may leave
cfs_rq and rt_rq's throttled when tasks are migrated away from a dead
cpu. (Kirill Tkhai)
- Robustify the sched topology setup code. (Peterz Zijlstra)
- Improve sched_feat() handling wrt. static_keys (Jason Baron)
- Misc fixes.
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
sched/fair: Fix 'make xmldocs' warning caused by missing description
sched: Use macro for magic number of -1 for setparam
sched: Robustify topology setup
sched: Fix sched_setparam() policy == -1 logic
sched: Allow wait_on_bit_action() functions to support a timeout
sched: Remove proliferation of wait_on_bit() action functions
sched/numa: Revert "Use effective_load() to balance NUMA loads"
sched: Fix static_key race with sched_feat()
sched: Remove extra static_key*() function indirection
sched/rt: Fix replenish_dl_entity() comments to match the current upstream code
sched: Transform resched_task() into resched_curr()
sched/deadline: Kill task_struct->pi_top_task
sched: Rework check_for_tasks()
sched/rt: Enqueue just unthrottled rt_rq back on the stack in __disable_runtime()
sched/fair: Disable runtime_enabled on dying rq
sched/numa: Change scan period code to match intent
sched/numa: Rework best node setting in task_numa_migrate()
sched/numa: Examine a task move when examining a task swap
sched/numa: Simplify task_numa_compare()
sched/numa: Use effective_load() to balance NUMA loads
...
Pull tracing updates from Steven Rostedt:
"This pull request has a lot of work done. The main thing is the
changes to the ftrace function callback infrastructure. It's
introducing a way to allow different functions to call directly
different trampolines instead of all calling the same "mcount" one.
The only user of this for now is the function graph tracer, which
always had a different trampoline, but the function tracer trampoline
was called and did basically nothing, and then the function graph
tracer trampoline was called. The difference now, is that the
function graph tracer trampoline can be called directly if a function
is only being traced by the function graph trampoline. If function
tracing is also happening on the same function, the old way is still
done.
The accounting for this takes up more memory when function graph
tracing is activated, as it needs to keep track of which functions it
uses. I have a new way that wont take as much memory, but it's not
ready yet for this merge window, and will have to wait for the next
one.
Another big change was the removal of the ftrace_start/stop() calls
that were used by the suspend/resume code that stopped function
tracing when entering into suspend and resume paths. The stop of
ftrace was done because there was some function that would crash the
system if one called smp_processor_id()! The stop/start was a big
hammer to solve the issue at the time, which was when ftrace was first
introduced into Linux. Now ftrace has better infrastructure to debug
such issues, and I found the problem function and labeled it with
"notrace" and function tracing can now safely be activated all the way
down into the guts of suspend and resume
Other changes include clean ups of uprobe code, clean up of the
trace_seq() code, and other various small fixes and clean ups to
ftrace and tracing"
* tag 'trace-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (57 commits)
ftrace: Add warning if tramp hash does not match nr_trampolines
ftrace: Fix trampoline hash update check on rec->flags
ring-buffer: Use rb_page_size() instead of open coded head_page size
ftrace: Rename ftrace_ops field from trampolines to nr_trampolines
tracing: Convert local function_graph functions to static
ftrace: Do not copy old hash when resetting
tracing: let user specify tracing_thresh after selecting function_graph
ring-buffer: Always run per-cpu ring buffer resize with schedule_work_on()
tracing: Remove function_trace_stop and HAVE_FUNCTION_TRACE_MCOUNT_TEST
s390/ftrace: remove check of obsolete variable function_trace_stop
arm64, ftrace: Remove check of obsolete variable function_trace_stop
Blackfin: ftrace: Remove check of obsolete variable function_trace_stop
metag: ftrace: Remove check of obsolete variable function_trace_stop
microblaze: ftrace: Remove check of obsolete variable function_trace_stop
MIPS: ftrace: Remove check of obsolete variable function_trace_stop
parisc: ftrace: Remove check of obsolete variable function_trace_stop
sh: ftrace: Remove check of obsolete variable function_trace_stop
sparc64,ftrace: Remove check of obsolete variable function_trace_stop
tile: ftrace: Remove check of obsolete variable function_trace_stop
ftrace: x86: Remove check of obsolete variable function_trace_stop
...
function_trace_stop is no longer used to disable function tracing.
This means that archs are no longer limited if it does not support
checking this variable in the mcount trampoline.
No need to use the list_func for archs that do not support this
obsolete method.
Acked-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
We always use resched_task() with rq->curr argument.
It's not possible to reschedule any task but rq's current.
The patch introduces resched_curr(struct rq *) to
replace all of the repeating patterns. The main aim
is cleanup, but there is a little size profit too:
(before)
$ size kernel/sched/built-in.o
text data bss dec hex filename
155274 16445 7042 178761 2ba49 kernel/sched/built-in.o
$ size vmlinux
text data bss dec hex filename
7411490 1178376 991232 9581098 92322a vmlinux
(after)
$ size kernel/sched/built-in.o
text data bss dec hex filename
155130 16445 7042 178617 2b9b9 kernel/sched/built-in.o
$ size vmlinux
text data bss dec hex filename
7411362 1178376 991232 9580970 9231aa vmlinux
I was choosing between resched_curr() and resched_rq(),
and the first name looks better for me.
A little lie in Documentation/trace/ftrace.txt. I have not
actually collected the tracing again. With a hope the patch
won't make execution times much worse :)
Signed-off-by: Kirill Tkhai <tkhai@yandex.ru>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20140628200219.1778.18735.stgit@localhost
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When using trace-vmscan-postprocess.pl for checking the file/anon rate
of scanning, we can find that it can not be performed. At the same
time, the following message will be reported:
WARNING: Format not as expected for event vmscan/mm_vmscan_lru_isolate
'file' != 'contig_taken' Fewer fields than expected in format at
./trace-vmscan-postprocess.pl line 171, <FORMAT> line 76.
In trace-vmscan-postprocess.pl, (contig_taken, contig_dirty, and
contig_failed) are be associated respectively to (nr_lumpy_taken,
nr_lumpy_dirty, and nr_lumpy_failed) for lumpy reclaim. Via commit
c53919adc0 ("mm: vmscan: remove lumpy reclaim"), lumpy reclaim had
already been removed by Mel, but the update for
trace-vmscan-postprocess.pl was missed.
Signed-off-by: Chen Yucong <slaoub@gmail.com>
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>
Pull tracing updates from Steven Rostedt:
"Lots of tweaks, small fixes, optimizations, and some helper functions
to help out the rest of the kernel to ease their use of trace events.
The big change for this release is the allowing of other tracers, such
as the latency tracers, to be used in the trace instances and allow
for function or function graph tracing to be in the top level
simultaneously"
* tag 'trace-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
tracing: Fix memory leak on instance deletion
tracing: Fix leak of ring buffer data when new instances creation fails
tracing/kprobes: Avoid self tests if tracing is disabled on boot up
tracing: Return error if ftrace_trace_arrays list is empty
tracing: Only calculate stats of tracepoint benchmarks for 2^32 times
tracing: Convert stddev into u64 in tracepoint benchmark
tracing: Introduce saved_cmdlines_size file
tracing: Add __get_dynamic_array_len() macro for trace events
tracing: Remove unused variable in trace_benchmark
tracing: Eliminate double free on failure of allocation on boot up
ftrace/x86: Call text_ip_addr() instead of the duplicated code
tracing: Print max callstack on stacktrace bug
tracing: Move locking of trace_cmdline_lock into start/stop seq calls
tracing: Try again for saved cmdline if failed due to locking
tracing: Have saved_cmdlines use the seq_read infrastructure
tracing: Add tracepoint benchmark tracepoint
tracing: Print nasty banner when trace_printk() is in use
tracing: Add funcgraph_tail option to print function name after closing braces
tracing: Eliminate duplicate TRACE_GRAPH_PRINT_xx defines
tracing: Add __bitmask() macro to trace events to cpumasks and other bitmasks
...
Pull trivial tree changes from Jiri Kosina:
"Usual pile of patches from trivial tree that make the world go round"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
staging: go7007: remove reference to CONFIG_KMOD
aic7xxx: Remove obsolete preprocessor define
of: dma: doc fixes
doc: fix incorrect formula to calculate CommitLimit value
doc: Note need of bc in the kernel build from 3.10 onwards
mm: Fix printk typo in dmapool.c
modpost: Fix comment typo "Modules.symvers"
Kconfig.debug: Grammar s/addition/additional/
wimax: Spelling s/than/that/, wording s/destinatary/recipient/
aic7xxx: Spelling s/termnation/termination/
arm64: mm: Remove superfluous "the" in comment
of: Spelling s/anonymouns/anonymous/
dma: imx-sdma: Spelling s/determnine/determine/
ath10k: Improve grammar in comments
ath6kl: Spelling s/determnine/determine/
of: Improve grammar for of_alias_get_id() documentation
drm/exynos: Spelling s/contro/control/
radio-bcm2048.c: fix wrong overflow check
doc: printk-formats: do not mention casts for u64/s64
doc: spelling error changes
...
In the function-graph tracer, add a funcgraph_tail option
to print the function name on all } lines, not just
functions whose first line is no longer in the trace
buffer.
If a function calls other traced functions, its total
time appears on its } line. This change allows grep
to be used to determine the function for which the
line corresponds.
Update Documentation/trace/ftrace.txt to describe
this new option.
Link: http://lkml.kernel.org/p/20140520221041.8359.6782.stgit@beardog.cce.hp.com
Signed-off-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
There are some code paths in the kernel that need to do some preparations
before it calls a tracepoint. As that code is worthless overhead when
the tracepoint is not enabled, it would be prudent to have that code
only run when the tracepoint is active. To accomplish this, all tracepoints
now get a static inline function called "trace_<tracepoint-name>_enabled()"
which returns true when the tracepoint is enabled and false otherwise.
As an added bonus, that function uses the static_key of the tracepoint
such that no branch is needed.
if (trace_mytracepoint_enabled()) {
arg = process_tp_arg();
trace_mytracepoint(arg);
}
Will keep the "process_tp_arg()" (which may be expensive to run) from
being executed when the tracepoint isn't enabled.
It's best to encapsulate the tracepoint itself in the if statement
just to keep races. For example, if you had:
if (trace_mytracepoint_enabled())
arg = process_tp_arg();
trace_mytracepoint(arg);
There's a chance that the tracepoint could be enabled just after the
if statement, and arg will be undefined when calling the tracepoint.
Link: http://lkml.kernel.org/r/20140506094407.507b6435@gandalf.local.home
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull tracing updates from Steven Rostedt:
"Most of the changes were largely clean ups, and some documentation.
But there were a few features that were added:
Uprobes now work with event triggers and multi buffers and have
support under ftrace and perf.
The big feature is that the function tracer can now be used within the
multi buffer instances. That is, you can now trace some functions in
one buffer, others in another buffer, all functions in a third buffer
and so on. They are basically agnostic from each other. This only
works for the function tracer and not for the function graph trace,
although you can have the function graph tracer running in the top
level buffer (or any tracer for that matter) and have different
function tracing going on in the sub buffers"
* tag 'trace-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (45 commits)
tracing: Add BUG_ON when stack end location is over written
tracepoint: Remove unused API functions
Revert "tracing: Move event storage for array from macro to standalone function"
ftrace: Constify ftrace_text_reserved
tracepoints: API doc update to tracepoint_probe_register() return value
tracepoints: API doc update to data argument
ftrace: Fix compilation warning about control_ops_free
ftrace/x86: BUG when ftrace recovery fails
ftrace: Warn on error when modifying ftrace function
ftrace: Remove freelist from struct dyn_ftrace
ftrace: Do not pass data to ftrace_dyn_arch_init
ftrace: Pass retval through return in ftrace_dyn_arch_init()
ftrace: Inline the code from ftrace_dyn_table_alloc()
ftrace: Cleanup of global variables ftrace_new_pgs and ftrace_update_cnt
tracing: Evaluate len expression only once in __dynamic_array macro
tracing: Correctly expand len expressions from __dynamic_array macro
tracing/module: Replace include of tracepoint.h with jump_label.h in module.h
tracing: Fix event header migrate.h to include tracepoint.h
tracing: Fix event header writeback.h to include tracepoint.h
tracing: Warn if a tracepoint is not set via debugfs
...
Fix double words "the the" in various files
within Documentations.
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
