Commit Graph

1089069 Commits

Author SHA1 Message Date
Gautam Menghani
154827f8e5 tracing: Initialize integer variable to prevent garbage return value
Initialize the integer variable to 0 to fix the clang scan warning:
Undefined or garbage value returned to caller
[core.uninitialized.UndefReturn]
        return ret;

Link: https://lkml.kernel.org/r/20220522061826.1751-1-gautammenghani201@gmail.com

Cc: stable@vger.kernel.org
Fixes: 8993665abc ("tracing/boot: Support multiple handlers for per-event histogram")
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Gautam Menghani <gautammenghani201@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:13:00 -04:00
Julia Lawall
50c697819d ftrace: Fix typo in comment
Spelling mistake (triple letters) in comment.
Detected with the help of Coccinelle.

Link: https://lkml.kernel.org/r/20220521111145.81697-81-Julia.Lawall@inria.fr

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:13:00 -04:00
Li kunyu
3a2bfec0b0 ftrace: Remove return value of ftrace_arch_modify_*()
All instances of the function ftrace_arch_modify_prepare() and
  ftrace_arch_modify_post_process() return zero. There's no point in
  checking their return value. Just have them be void functions.

Link: https://lkml.kernel.org/r/20220518023639.4065-1-kunyu@nfschina.com

Signed-off-by: Li kunyu <kunyu@nfschina.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:13:00 -04:00
liqiong
2decd16f47 tracing: Cleanup code by removing init "char *name"
The pointer is assigned to "type->name" anyway. no need to
initialize with "preemption".

Link: https://lkml.kernel.org/r/20220513075221.26275-1-liqiong@nfschina.com

Signed-off-by: liqiong <liqiong@nfschina.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:13:00 -04:00
liqiong
2d601b9864 tracing: Change "char *" string form to "char []"
The "char []" string form declares a single variable. It is better
than "char *" which creates two variables in the final assembly.

Link: https://lkml.kernel.org/r/20220512143230.28796-1-liqiong@nfschina.com

Signed-off-by: liqiong <liqiong@nfschina.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:13:00 -04:00
Daniel Bristot de Oliveira
9c556e5a4d tracing/timerlat: Do not wakeup the thread if the trace stops at the IRQ
There is no need to wakeup the timerlat/ thread if stop tracing is hit
at the timerlat's IRQ handler.

Return before waking up timerlat's thread.

Link: https://lkml.kernel.org/r/b392356c91b56aedd2b289513cc56a84cf87e60d.1652175637.git.bristot@kernel.org

Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:13:00 -04:00
Daniel Bristot de Oliveira
4dd2aea24e tracing/timerlat: Print stacktrace in the IRQ handler if needed
If print_stack and stop_tracing_us are set, and stop_tracing_us is hit
with latency higher than or equal to print_stack, print the
stack at the IRQ handler as it is useful to define the root cause for
the IRQ latency.

Link: https://lkml.kernel.org/r/fd04530ce98ae9270e41bb124ee5bf67b05ecfed.1652175637.git.bristot@kernel.org

Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:13:00 -04:00
Daniel Bristot de Oliveira
aa748949b4 tracing/timerlat: Notify IRQ new max latency only if stop tracing is set
Currently, the notification of a new max latency is sent from
timerlat's IRQ handler anytime a new max latency is found.

While this behavior is not wrong, the send IPI overhead itself
will increase the thread latency and that is not the desired
effect (tracing overhead).

Moreover, the thread will notify a new max latency again because
the thread latency as it is always higher than the IRQ latency
that woke it up.

The only case in which it is helpful to notify a new max latency
from IRQ is when stop tracing (for the IRQ) is set, as in this
case, the thread will not be dispatched.

Notify a new max latency from the IRQ handler only if stop tracing is
set for the IRQ handler.

Link: https://lkml.kernel.org/r/2c2d9a56c0886c8402ba320de32856cbbb10c2bb.1652175637.git.bristot@kernel.org

Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Reported-by: Clark Williams <williams@redhat.com>
Fixes: a955d7eac1 ("trace: Add timerlat tracer")
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:13:00 -04:00
Masami Hiramatsu
4399404918 kprobes: Fix build errors with CONFIG_KRETPROBES=n
Max Filippov reported:

When building kernel with CONFIG_KRETPROBES=n kernel/kprobes.c
compilation fails with the following messages:

  kernel/kprobes.c: In function ‘recycle_rp_inst’:
  kernel/kprobes.c:1273:32: error: implicit declaration of function
                                   ‘get_kretprobe’

  kernel/kprobes.c: In function ‘kprobe_flush_task’:
  kernel/kprobes.c:1299:35: error: ‘struct task_struct’ has no member
                                   named ‘kretprobe_instances’

This came from the commit d741bf41d7 ("kprobes: Remove
kretprobe hash") which introduced get_kretprobe() and
kretprobe_instances member in task_struct when CONFIG_KRETPROBES=y,
but did not make recycle_rp_inst() and kprobe_flush_task()
depending on CONFIG_KRETPORBES.

Since those functions are only used for kretprobe, move those
functions into #ifdef CONFIG_KRETPROBE area.

Link: https://lkml.kernel.org/r/165163539094.74407.3838114721073251225.stgit@devnote2

Reported-by: Max Filippov <jcmvbkbc@gmail.com>
Fixes: d741bf41d7 ("kprobes: Remove kretprobe hash")
Cc: "Naveen N . Rao" <naveen.n.rao@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S . Miller" <davem@davemloft.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:12:59 -04:00
Wonhyuk Yang
b27f266f74 tracing: Fix return value of trace_pid_write()
Setting set_event_pid with trailing whitespace lead to endless write
system calls like below.

    $ strace echo "123 " > /sys/kernel/debug/tracing/set_event_pid
    execve("/usr/bin/echo", ["echo", "123 "], ...) = 0
    ...
    write(1, "123 \n", 5)                   = 4
    write(1, "\n", 1)                       = 0
    write(1, "\n", 1)                       = 0
    write(1, "\n", 1)                       = 0
    write(1, "\n", 1)                       = 0
    write(1, "\n", 1)                       = 0
    ....

This is because, the result of trace_get_user's are not returned when it
read at least one pid. To fix it, update read variable even if
parser->idx == 0.

The result of applied patch is below.

    $ strace echo "123 " > /sys/kernel/debug/tracing/set_event_pid
    execve("/usr/bin/echo", ["echo", "123 "], ...) = 0
    ...
    write(1, "123 \n", 5)                   = 5
    close(1)                                = 0

Link: https://lkml.kernel.org/r/20220503050546.288911-1-vvghjk1234@gmail.com

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Baik Song An <bsahn@etri.re.kr>
Cc: Hong Yeon Kim <kimhy@etri.re.kr>
Cc: Taeung Song <taeung@reallinux.co.kr>
Cc: linuxgeek@linuxgeek.io
Cc: stable@vger.kernel.org
Fixes: 4909010788 ("tracing: Add set_event_pid directory for future use")
Signed-off-by: Wonhyuk Yang <vvghjk1234@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:12:59 -04:00
Keita Suzuki
99696a2592 tracing: Fix potential double free in create_var_ref()
In create_var_ref(), init_var_ref() is called to initialize the fields
of variable ref_field, which is allocated in the previous function call
to create_hist_field(). Function init_var_ref() allocates the
corresponding fields such as ref_field->system, but frees these fields
when the function encounters an error. The caller later calls
destroy_hist_field() to conduct error handling, which frees the fields
and the variable itself. This results in double free of the fields which
are already freed in the previous function.

Fix this by storing NULL to the corresponding fields when they are freed
in init_var_ref().

Link: https://lkml.kernel.org/r/20220425063739.3859998-1-keitasuzuki.park@sslab.ics.keio.ac.jp

Fixes: 067fe038e7 ("tracing: Add variable reference handling to hist triggers")
CC: stable@vger.kernel.org
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Keita Suzuki <keitasuzuki.park@sslab.ics.keio.ac.jp>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:12:59 -04:00
Yuntao Wang
cb24693d94 tracing: Use strim() to remove whitespace instead of doing it manually
The tracing_set_trace_write() function just removes the trailing whitespace
from the user supplied tracer name, but the leading whitespace should also
be removed.

In addition, if the user supplied tracer name contains only a few
whitespace characters, the first one will not be removed using the current
method, which results it a single whitespace character left in the buf.

To fix all of these issues, we use strim() to correctly remove both the
leading and trailing whitespace.

Link: https://lkml.kernel.org/r/20220121095623.1826679-1-ytcoode@gmail.com

Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:12:59 -04:00
Yuntao Wang
2889c658b2 ftrace: Deal with error return code of the ftrace_process_locs() function
The ftrace_process_locs() function may return -ENOMEM error code, which
should be handled by the callers.

Link: https://lkml.kernel.org/r/20220120065949.1813231-1-ytcoode@gmail.com

Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:12:59 -04:00
Yuntao Wang
e4931b824a tracing: Use trace_create_file() to simplify creation of tracefs entries
Creating tracefs entries with tracefs_create_file() followed by pr_warn()
is tedious and repetitive, we can use trace_create_file() to simplify
this process and make the code more readable.

Link: https://lkml.kernel.org/r/20220114131052.534382-1-ytcoode@gmail.com

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 21:12:52 -04:00
Li Huafei
e35c2d8e22 tracing: Reset the function filter after completing trampoline/graph selftest
The direct trampoline and graph coexistence test sets global_ops to
trace only 'trace_selftest_dynamic_test_func', but does not reset it
after the test is completed, resulting in the function filter being set
already after the system starts. Although it can be reset through the
tracefs interface, it is more or less confusing to the user, and we
should reset it to trace all functions after the trampoline/graph test
completes.

Link: https://lkml.kernel.org/r/20220427034119.24668-1-lihuafei1@huawei.com
Link: https://lore.kernel.org/all/20220418073958.104029-1-lihuafei1@huawei.com/

Fixes: 130c080658 ("tracing: Add trampoline/graph selftest")
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-25 16:57:37 -04:00
Steven Rostedt (Google)
499f12168a tracing: Have event format check not flag %p* on __get_dynamic_array()
The print fmt check against trace events to make sure that the format does
not use pointers that may be freed from the time of the trace to the time
the event is read, gives a false positive on %pISpc when reading data that
was saved in __get_dynamic_array() when it is perfectly fine to do so, as
the data being read is on the ring buffer.

Link: https://lore.kernel.org/all/20220407144524.2a592ed6@canb.auug.org.au/

Cc: stable@vger.kernel.org
Fixes: 5013f454a3 ("tracing: Add check of trace event print fmts for dereferencing pointers")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-25 16:57:37 -04:00
Jakob Koschel
ba27d85558 tracing: Remove check of list iterator against head past the loop body
When list_for_each_entry() completes the iteration over the whole list
without breaking the loop, the iterator value will be a bogus pointer
computed based on the head element.

While it is safe to use the pointer to determine if it was computed
based on the head element, either with list_entry_is_head() or
&pos->member == head, using the iterator variable after the loop should
be avoided.

In preparation to limit the scope of a list iterator to the list
traversal loop, use a dedicated pointer to point to the found element [1].

Link: https://lkml.kernel.org/r/20220427170734.819891-5-jakobkoschel@gmail.com

Cc: Ingo Molnar <mingo@redhat.com>
Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-27 17:19:31 -04:00
Jakob Koschel
45e333ce2a tracing: Replace usage of found with dedicated list iterator variable
To move the list iterator variable into the list_for_each_entry_*()
macro in the future it should be avoided to use the list iterator
variable after the loop body.

To *never* use the list iterator variable after the loop it was
concluded to use a separate iterator variable instead of a
found boolean [1].

This removes the need to use a found variable and simply checking if
the variable was set, can determine if the break/goto was hit.

Link: https://lkml.kernel.org/r/20220427170734.819891-4-jakobkoschel@gmail.com

Cc: Ingo Molnar <mingo@redhat.com>
Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-27 17:19:31 -04:00
Jakob Koschel
99d8ae4ec8 tracing: Remove usage of list iterator variable after the loop
In preparation to limit the scope of a list iterator to the list
traversal loop, use a dedicated pointer to point to the found element
[1].

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Link: https://lkml.kernel.org/r/20220427170734.819891-3-jakobkoschel@gmail.com

Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-27 17:19:30 -04:00
Jakob Koschel
1da27a2505 tracing: Remove usage of list iterator after the loop body
In preparation to limit the scope of the list iterator variable to the
traversal loop, use a dedicated pointer to point to the found element
[1].

Before, the code implicitly used the head when no element was found
when using &pos->list. Since the new variable is only set if an
element was found, the head needs to be used explicitly if the
variable is NULL.

Link: https://lkml.kernel.org/r/20220427170734.819891-2-jakobkoschel@gmail.com

Cc: Ingo Molnar <mingo@redhat.com>
Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-27 17:19:30 -04:00
Kurt Kanzenbach
4d1257bbc2 tracing: Add documentation for trace clock tai
Add documentation for newly introduced trace clock "tai".
This clock corresponds to CLOCK_TAI.

Link: https://lkml.kernel.org/r/20220414091805.89667-4-kurt@linutronix.de

Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-27 17:19:30 -04:00
Kurt Kanzenbach
c575afe21c tracing: Introduce trace clock tai
A fast/NMI safe accessor for CLOCK_TAI has been introduced.
Use it for adding the additional trace clock "tai".

Link: https://lkml.kernel.org/r/20220414091805.89667-3-kurt@linutronix.de

Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-27 17:19:30 -04:00
Steven Rostedt (Google)
f03f2abce4 ring-buffer: Have 32 bit time stamps use all 64 bits
When the new logic was made to handle deltas of events from interrupts
that interrupted other events, it required 64 bit local atomics.
Unfortunately, 64 bit local atomics are expensive on 32 bit architectures.
Thus, commit 10464b4aa6 ("ring-buffer: Add rb_time_t 64 bit operations
for speeding up 32 bit") created a type of seq lock timer for 32 bits.
It used two 32 bit local atomics, but required 2 bits from them each for
synchronization, making it only 60 bits.

Add a new "msb" field to hold the extra 4 bits that are cut off.

Link: https://lore.kernel.org/all/20220426175338.3807ca4f@gandalf.local.home/
Link: https://lkml.kernel.org/r/20220427170812.53cc7139@gandalf.local.home

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-27 17:19:30 -04:00
Steven Rostedt (Google)
6695da58f9 ring-buffer: Have absolute time stamps handle large numbers
There's an absolute timestamp event in the ring buffer, but this only
saves 59 bits of the timestamp, as the 5 MSB is used for meta data
(stating it is an absolute time stamp). This was never an issue as all the
clocks currently in use never used those 5 MSB. But now there's a new
clock (TAI) that does.

To handle this case, when reading an absolute timestamp, a previous full
timestamp is passed in, and the 5 MSB of that timestamp is OR'd to the
absolute timestamp (if any of the 5 MSB are set), and then to test for
overflow, if the new result is smaller than the passed in previous
timestamp, then 1 << 59 is added to it.

All the extra processing is done on the reader "slow" path, with the
exception of the "too big delta" check, and the reading of timestamps
for histograms.

Note, libtraceevent will need to be updated to handle this case as well.
But this is not a user space regression, as user space was never able to
handle any timestamps that used more than 59 bits.

Link: https://lore.kernel.org/all/20220426175338.3807ca4f@gandalf.local.home/
Link: https://lkml.kernel.org/r/20220427153339.16c33f75@gandalf.local.home

Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-27 15:59:44 -04:00
Mark-PK Tsai
6621a70046 tracing: make tracer_init_tracefs initcall asynchronous
Move trace_eval_init() to subsys_initcall to make it start
earlier.
And to avoid tracer_init_tracefs being blocked by
trace_event_sem which trace_eval_init() hold [1],
queue tracer_init_tracefs() to eval_map_wq to let
the two works being executed sequentially.

It can speed up the initialization of kernel as result
of making tracer_init_tracefs asynchronous.

On my arm64 platform, it reduce ~20ms of 125ms which total
time do_initcalls spend.

Link: https://lkml.kernel.org/r/20220426122407.17042-3-mark-pk.tsai@mediatek.com

[1]: https://lore.kernel.org/r/68d7b3327052757d0cd6359a6c9015a85b437232.camel@pengutronix.de
Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:52 -04:00
Mark-PK Tsai
ef9188bcc6 tracing: Avoid adding tracer option before update_tracer_options
To prepare for support asynchronous tracer_init_tracefs initcall,
avoid calling create_trace_option_files before __update_tracer_options.
Otherwise, create_trace_option_files will show warning because
some tracers in trace_types list are already in tr->topts.

For example, hwlat_tracer call register_tracer in late_initcall,
and global_trace.dir is already created in tracing_init_dentry,
hwlat_tracer will be put into tr->topts.
Then if the __update_tracer_options is executed after hwlat_tracer
registered, create_trace_option_files find that hwlat_tracer is
already in tr->topts.

Link: https://lkml.kernel.org/r/20220426122407.17042-2-mark-pk.tsai@mediatek.com

Link: https://lore.kernel.org/lkml/20220322133339.GA32582@xsang-OptiPlex-9020/
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:52 -04:00
Wan Jiabing
ed888241a0 ring-buffer: Simplify if-if to if-else
Use if and else instead of if(A) and if (!A).

Link: https://lkml.kernel.org/r/20220426070628.167565-1-wanjiabing@vivo.com

Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:52 -04:00
Guo Zhengkui
4ee51101e9 tracing: Use WARN instead of printk and WARN_ON
Use `WARN(cond, ...)` instead of `if (cond)` + `printk(...)` +
`WARN_ON(1)`.

Link: https://lkml.kernel.org/r/20220424131932.3606-1-guozhengkui@vivo.com

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Guo Zhengkui <guozhengkui@vivo.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:52 -04:00
Jun Miao
12025abdc8 tracing: Fix sleeping function called from invalid context on RT kernel
When setting bootparams="trace_event=initcall:initcall_start tp_printk=1" in the
cmdline, the output_printk() was called, and the spin_lock_irqsave() was called in the
atomic and irq disable interrupt context suitation. On the PREEMPT_RT kernel,
these locks are replaced with sleepable rt-spinlock, so the stack calltrace will
be triggered.
Fix it by raw_spin_lock_irqsave when PREEMPT_RT and "trace_event=initcall:initcall_start
tp_printk=1" enabled.

 BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46
 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0
 preempt_count: 2, expected: 0
 RCU nest depth: 0, expected: 0
 Preemption disabled at:
 [<ffffffff8992303e>] try_to_wake_up+0x7e/0xba0
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.1-rt17+ #19 34c5812404187a875f32bee7977f7367f9679ea7
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x60/0x8c
  dump_stack+0x10/0x12
  __might_resched.cold+0x11d/0x155
  rt_spin_lock+0x40/0x70
  trace_event_buffer_commit+0x2fa/0x4c0
  ? map_vsyscall+0x93/0x93
  trace_event_raw_event_initcall_start+0xbe/0x110
  ? perf_trace_initcall_finish+0x210/0x210
  ? probe_sched_wakeup+0x34/0x40
  ? ttwu_do_wakeup+0xda/0x310
  ? trace_hardirqs_on+0x35/0x170
  ? map_vsyscall+0x93/0x93
  do_one_initcall+0x217/0x3c0
  ? trace_event_raw_event_initcall_level+0x170/0x170
  ? push_cpu_stop+0x400/0x400
  ? cblist_init_generic+0x241/0x290
  kernel_init_freeable+0x1ac/0x347
  ? _raw_spin_unlock_irq+0x65/0x80
  ? rest_init+0xf0/0xf0
  kernel_init+0x1e/0x150
  ret_from_fork+0x22/0x30
  </TASK>

Link: https://lkml.kernel.org/r/20220419013910.894370-1-jun.miao@intel.com

Signed-off-by: Jun Miao <jun.miao@intel.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:52 -04:00
Ammar Faizi
69686fcbdc tracing: Change if (strlen(glob)) to if (glob[0])
No need to traverse to the end of string. If the first byte is not a NUL
char, it's guaranteed `if (strlen(glob))` is true.

Link: https://lkml.kernel.org/r/20220417185630.199062-3-ammarfaizi2@gnuweeb.org

Cc: Ingo Molnar <mingo@redhat.com>
Cc: GNU/Weeb Mailing List <gwml@vger.gnuweeb.org>
Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:52 -04:00
Ammar Faizi
97a5d2e5e3 tracing: Return -EINVAL if WARN_ON(!glob) triggered in event_hist_trigger_parse()
If `WARN_ON(!glob)` is ever triggered, we will still continue executing
the next lines. This will trigger the more serious problem, a NULL
pointer dereference bug.

Just return -EINVAL if @glob is NULL.

Link: https://lkml.kernel.org/r/20220417185630.199062-2-ammarfaizi2@gnuweeb.org

Cc: Ingo Molnar <mingo@redhat.com>
Cc: GNU/Weeb Mailing List <gwml@vger.gnuweeb.org>
Signed-off-by: Ammar Faizi <ammarfaizi2@gnuweeb.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:52 -04:00
Jeff Xie
cb1c45fb68 tracing: Make tp_printk work on syscall tracepoints
Currently the tp_printk option has no effect on syscall tracepoint.
When adding the kernel option parameter tp_printk, then:

echo 1 > /sys/kernel/debug/tracing/events/syscalls/enable

When running any application, no trace information is printed on the
terminal.

Now added printk for syscall tracepoints.

Link: https://lkml.kernel.org/r/20220410145025.681144-1-xiehuan09@gmail.com

Signed-off-by: Jeff Xie <xiehuan09@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:52 -04:00
Masami Hiramatsu
2f51efc6b7 docs: bootconfig: Add how to embed the bootconfig into kernel
Add a description how to embed the bootconfig file into kernel.

Link: https://lkml.kernel.org/r/164921228987.1090670.16843569536974147213.stgit@devnote2

Cc: Padmanabha Srinivasaiah <treasure4paddy@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:51 -04:00
Masami Hiramatsu
a2a9d67a26 bootconfig: Support embedding a bootconfig file in kernel
This allows kernel developer to embed a default bootconfig file in
the kernel instead of embedding it in the initrd. This will be good
for who are using the kernel without initrd, or who needs a default
bootconfigs.
This needs to set two kconfigs: CONFIG_BOOT_CONFIG_EMBED=y and set
the file path to CONFIG_BOOT_CONFIG_EMBED_FILE.

Note that you still need 'bootconfig' command line option to load the
embedded bootconfig. Also if you boot using an initrd with a different
bootconfig, the kernel will use the bootconfig in the initrd, instead
of the default bootconfig.

Link: https://lkml.kernel.org/r/164921227943.1090670.14035119557571329218.stgit@devnote2

Cc: Padmanabha Srinivasaiah <treasure4paddy@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:51 -04:00
Masami Hiramatsu
765b8552a2 bootconfig: Check the checksum before removing the bootconfig from initrd
Check the bootconfig's checksum before removing the bootconfig data
from initrd to avoid modifying initrd by mistake.
This will also simplifies the get_boot_config_from_initrd() interface.

Link: https://lkml.kernel.org/r/164921226891.1090670.16955839243639298134.stgit@devnote2

Cc: Padmanabha Srinivasaiah <treasure4paddy@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:51 -04:00
Masami Hiramatsu
6014a23638 bootconfig: Make the bootconfig.o as a normal object file
Since the APIs defined in the bootconfig.o are not individually used,
it is meaningless to build it as library by lib-y. Use obj-y for that.

Link: https://lkml.kernel.org/r/164921225875.1090670.15565363126983098971.stgit@devnote2

Cc: Padmanabha Srinivasaiah <treasure4paddy@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Linux Kbuild mailing list <linux-kbuild@vger.kernel.org>
Reported-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:51 -04:00
Yang Li
adaa0a9f06 tracing: Fix tracing_map_sort_entries() kernel-doc comment
Add the description of @n_sort_keys and make @sort_key ->
@sort_keys in tracing_map_sort_entries() kernel-doc comment
to remove warnings found by running scripts/kernel-doc, which
is caused by using 'make W=1'.

kernel/trace/tracing_map.c:1073: warning: Function parameter or member
'sort_keys' not described in 'tracing_map_sort_entries'
kernel/trace/tracing_map.c:1073: warning: Function parameter or member
'n_sort_keys' not described in 'tracing_map_sort_entries'
kernel/trace/tracing_map.c:1073: warning: Excess function parameter
'sort_key' description in 'tracing_map_sort_entries'

Link: https://lkml.kernel.org/r/20220402072015.45864-1-yang.lee@linux.alibaba.com

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:51 -04:00
Christophe Leroy
3eaf17f502 MAINTAINERS: Enlarge coverage of TRACING inside architectures
Most architectures have ftrace related stuff in arch/*/kernel/ftrace.c
but powerpc has it spread in multiple files located in
arch/powerpc/kernel/trace/
In several architectures, there are also additional files containing
'ftrace' as part of the name but with some prefix or suffix.

Use wildcards to enlarge coverage.

With arch/*/*/*/*ftrace*:
	arch/alpha/include/asm/ftrace.h
	arch/arm64/include/asm/ftrace.h
	arch/arm/include/asm/ftrace.h
	arch/csky/include/asm/ftrace.h
	arch/csky/kernel/probes/ftrace.c
	arch/ia64/include/asm/ftrace.h
	arch/m68k/include/asm/ftrace.h
	arch/microblaze/include/asm/ftrace.h
	arch/mips/include/asm/ftrace.h
	arch/nds32/include/asm/ftrace.h
	arch/parisc/include/asm/ftrace.h
	arch/powerpc/include/asm/ftrace.h
	arch/powerpc/kernel/trace/ftrace_64_pg.S
	arch/powerpc/kernel/trace/ftrace.c
	arch/powerpc/kernel/trace/ftrace_low.S
	arch/powerpc/kernel/trace/ftrace_mprofile.S
	arch/riscv/include/asm/ftrace.h
	arch/riscv/kernel/probes/ftrace.c
	arch/s390/include/asm/ftrace.h
	arch/s390/include/asm/ftrace.lds.h
	arch/sh/include/asm/ftrace.h
	arch/sparc/include/asm/ftrace.h
	arch/x86/include/asm/ftrace.h
	arch/x86/kernel/kprobes/ftrace.c
	arch/xtensa/include/asm/ftrace.h

With arch/*/*/*ftrace*:
	arch/arm64/kernel/entry-ftrace.S
	arch/arm64/kernel/ftrace.c
	arch/arm/kernel/entry-ftrace.S
	arch/arm/kernel/ftrace.c
	arch/csky/kernel/ftrace.c
	arch/ia64/kernel/ftrace.c
	arch/microblaze/kernel/ftrace.c
	arch/mips/kernel/ftrace.c
	arch/nds32/kernel/ftrace.c
	arch/parisc/kernel/ftrace.c
	arch/powerpc/kernel/kprobes-ftrace.c
	arch/riscv/kernel/ftrace.c
	arch/s390/kernel/ftrace.c
	arch/s390/kernel/ftrace.h
	arch/sh/kernel/ftrace.c
	arch/sparc/kernel/ftrace.c
	arch/x86/kernel/ftrace_32.S
	arch/x86/kernel/ftrace_64.S
	arch/x86/kernel/ftrace.c

Link: https://lkml.kernel.org/r/e8338c0ad0e73991cbd8f31c215b16ea4efe212d.1648189904.git.christophe.leroy@csgroup.eu

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:51 -04:00
Jiapeng Chong
3b57d8477c tracing: Fix kernel-doc
Fix the following W=1 kernel warnings:

kernel/trace/trace.c:1181: warning: expecting prototype for
tracing_snapshot_cond_data(). Prototype was for
tracing_cond_snapshot_data() instead.

Link: https://lkml.kernel.org/r/20220218100849.122038-1-jiapeng.chong@linux.alibaba.com

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:51 -04:00
Oscar Shiang
cf2adec747 tracing: Fix inconsistent style of mini-HOWTO
Each description should start with a hyphen and a space. Insert
spaces to fix it.

Link: https://lkml.kernel.org/r/TYCP286MB19130AA4A9C6FC5A8793DED2A1359@TYCP286MB1913.JPNP286.PROD.OUTLOOK.COM

Signed-off-by: Oscar Shiang <oscar0225@livemail.tw>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:51 -04:00
Tom Zanussi
a7e6b7dcfb tracing: Separate hist state updates from hist registration
hist_register_trigger() handles both new hist registration as well as
existing hist registration through event_command.reg().

Adding a new function, existing_hist_update_only(), that checks and
updates existing histograms and exits after doing so allows the
confusing logic in event_hist_trigger_parse() to be simplified.

Link: https://lkml.kernel.org/r/211b2cd3e3d7e00f4f8ad45ef8b33063da6a7e05.1644010576.git.zanussi@kernel.org

Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:50 -04:00
Tom Zanussi
e1f187d09e tracing: Have existing event_command.parse() implementations use helpers
Simplify the existing event_command.parse() implementations by having
them make use of the helper functions previously introduced.

Link: https://lkml.kernel.org/r/b353e3427a81f9d3adafd98fd7d73e78a8209f43.1644010576.git.zanussi@kernel.org

Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:50 -04:00
Tom Zanussi
4767054195 tracing: Remove redundant trigger_ops params
Since event_trigger_data contains the .ops trigger_ops field, there's
no reason to pass the trigger_ops separately. Remove it as a param
from functions whenever event_trigger_data is passed.

Link: https://lkml.kernel.org/r/9856c9bc81bde57077f5b8d6f8faa47156c6354a.1644010575.git.zanussi@kernel.org

Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:50 -04:00
Tom Zanussi
b8cc44a4d3 tracing: Remove logic for registering multiple event triggers at a time
Code for registering triggers assumes it's possible to register more
than one trigger at a time.  In fact, it's unimplemented and there
doesn't seem to be a reason to do that.

Remove the n_registered param from event_trigger_register() and fix up
callers.

Doing so simplifies the logic in event_trigger_register to the point
that it just becomes a wrapper calling event_command.reg().

It also removes the problematic call to event_command.unreg() in case
of failure.  A new function, event_trigger_unregister() is also added
for callers to call themselves.

The changes to trace_events_hist.c simply allow compilation; a
separate patch follows which updates the hist triggers to work
correctly with the new changes.

Link: https://lkml.kernel.org/r/6149fec7a139d93e84fa4535672fb5bef88006b0.1644010575.git.zanussi@kernel.org

Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:50 -04:00
Tom Rix
217d8c05ec tracing: Cleanup double word in comment
Remove the second 'is' and 'to'.

Link: https://lkml.kernel.org/r/20220207131216.2059997-1-trix@redhat.com

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-04-26 17:58:50 -04:00
Kurt Kanzenbach
3dc6ffae2d timekeeping: Introduce fast accessor to clock tai
Introduce fast/NMI safe accessor to clock tai for tracing. The Linux kernel
tracing infrastructure has support for using different clocks to generate
timestamps for trace events. Especially in TSN networks it's useful to have TAI
as trace clock, because the application scheduling is done in accordance to the
network time, which is based on TAI. With a tai trace_clock in place, it becomes
very convenient to correlate network activity with Linux kernel application
traces.

Use the same implementation as ktime_get_boot_fast_ns() does by reading the
monotonic time and adding the TAI offset. The same limitations as for the fast
boot implementation apply. The TAI offset may change at run time e.g., by
setting the time or using adjtimex() with an offset. However, these kind of
offset changes are rare events. Nevertheless, the user has to be aware and deal
with it in post processing.

An alternative approach would be to use the same implementation as
ktime_get_real_fast_ns() does. However, this requires to add an additional u64
member to the tk_read_base struct. This struct together with a seqcount is
designed to fit into a single cache line on 64 bit architectures. Adding a new
member would violate this constraint.

Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20220414091805.89667-2-kurt@linutronix.de
2022-04-14 16:19:30 +02:00
Linus Torvalds
ce522ba9ef Linux 5.18-rc2 2022-04-10 14:21:36 -10:00
Linus Torvalds
8b57b30461 Serial driver fix for 5.18-rc2
This is a single serial driver fix for a build issue that showed up due
 to changes that came in through the tty tree in 5.18-rc1 that were
 missed previously.  It resolves a build error with the mpc52xx_uart
 driver.
 
 It has been in linux-next this week with no reported problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull serial driver fix from Greg KH:
 "This is a single serial driver fix for a build issue that showed up
  due to changes that came in through the tty tree in 5.18-rc1 that were
  missed previously. It resolves a build error with the mpc52xx_uart
  driver.

  It has been in linux-next this week with no reported problems"

* tag 'tty-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: serial: mpc52xx_uart: make rx/tx hooks return unsigned, part II.
2022-04-10 10:08:50 -10:00
Linus Torvalds
95aa17c36d Staging driver fix for 5.18-rc2
Here is a single staging driver fix for 5.18-rc2 that resolves an endian
 issue for the r8188eu driver.  It has been in linux-next all this week
 with no reported problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 -----END PGP SIGNATURE-----

Merge tag 'staging-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging driver fix from Greg KH:
 "Here is a single staging driver fix for 5.18-rc2 that resolves an
  endian issue for the r8188eu driver. It has been in linux-next all
  this week with no reported problems"

* tag 'staging-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: r8188eu: Fix PPPoE tag insertion on little endian systems
2022-04-10 10:04:30 -10:00
Linus Torvalds
33563138ac Driver core changes for 5.18-rc2
Here are 2 small driver core changes for 5.18-rc2.
 
 They are the final bits in the removal of the default_attrs field in
 struct kobj_type.  I had to wait until after 5.18-rc1 for all of the
 changes to do this came in through different development trees, and then
 one new user snuck in.  So this series has 2 changes:
 	- removal of the default_attrs field in the powerpc/pseries/vas
 	  code.  Change has been acked by the PPC maintainers to come
 	  through this tree
 	- removal of default_attrs from struct kobj_type now that all
 	  in-kernel users are removed.  This cleans up the kobject code
 	  a little bit and removes some duplicated functionality that
 	  confused people (now there is only one way to do default
 	  groups.)
 
 All of these have been in linux-next for all of this week with no
 reported problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 =L+Uc
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here are two small driver core changes for 5.18-rc2.

  They are the final bits in the removal of the default_attrs field in
  struct kobj_type. I had to wait until after 5.18-rc1 for all of the
  changes to do this came in through different development trees, and
  then one new user snuck in. So this series has two changes:

   - removal of the default_attrs field in the powerpc/pseries/vas code.

     The change has been acked by the PPC maintainers to come through
     this tree

   - removal of default_attrs from struct kobj_type now that all
     in-kernel users are removed.

     This cleans up the kobject code a little bit and removes some
     duplicated functionality that confused people (now there is only
     one way to do default groups)

  Both of these have been in linux-next for all of this week with no
  reported problems"

* tag 'driver-core-5.18-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  kobject: kobj_type: remove default_attrs
  powerpc/pseries/vas: use default_groups in kobj_type
2022-04-10 09:55:09 -10:00