- The ring buffer is no longer disabled when reading the trace file.
The trace_pipe file was made to be used for live tracing and reading
as it acted like the normal producer/consumer. As the trace file
would not consume the data, the easy way of handling it was to just
disable writes to the ring buffer. This came to a surprise to the
BPF folks who complained about lost events due to reading.
This is no longer an issue. If someone wants to keep the old disabling
there's a new option "pause-on-trace" that can be set.
- New set_ftrace_notrace_pid file. PIDs in this file will not be traced
by the function tracer. Similar to set_ftrace_pid, which makes the
function tracer only trace those tasks with PIDs in the file, the
set_ftrace_notrace_pid does the reverse.
- New set_event_notrace_pid file. PIDs in this file will cause events
not to be traced if triggered by a task with a matching PID.
Similar to the set_event_pid file but will not be traced.
Note, sched_waking and sched_switch events may still be trace if
one of the tasks referenced by those events contains a PID that
is allowed to be traced.
Tracing related features:
- New bootconfig option, that is attached to the initrd file.
If bootconfig is on the command line, then the initrd file
is searched looking for a bootconfig appended at the end.
- New GPU tracepoint infrastructure to help the gfx drivers to get
off debugfs (acked by Greg Kroah-Hartman)
Other minor updates and fixes.
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Merge tag 'trace-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"New tracing features:
- The ring buffer is no longer disabled when reading the trace file.
The trace_pipe file was made to be used for live tracing and
reading as it acted like the normal producer/consumer. As the trace
file would not consume the data, the easy way of handling it was to
just disable writes to the ring buffer.
This came to a surprise to the BPF folks who complained about lost
events due to reading. This is no longer an issue. If someone wants
to keep the old disabling there's a new option "pause-on-trace"
that can be set.
- New set_ftrace_notrace_pid file. PIDs in this file will not be
traced by the function tracer.
Similar to set_ftrace_pid, which makes the function tracer only
trace those tasks with PIDs in the file, the set_ftrace_notrace_pid
does the reverse.
- New set_event_notrace_pid file. PIDs in this file will cause events
not to be traced if triggered by a task with a matching PID.
Similar to the set_event_pid file but will not be traced. Note,
sched_waking and sched_switch events may still be traced if one of
the tasks referenced by those events contains a PID that is allowed
to be traced.
Tracing related features:
- New bootconfig option, that is attached to the initrd file.
If bootconfig is on the command line, then the initrd file is
searched looking for a bootconfig appended at the end.
- New GPU tracepoint infrastructure to help the gfx drivers to get
off debugfs (acked by Greg Kroah-Hartman)
And other minor updates and fixes"
* tag 'trace-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (27 commits)
tracing: Do not allocate buffer in trace_find_next_entry() in atomic
tracing: Add documentation on set_ftrace_notrace_pid and set_event_notrace_pid
selftests/ftrace: Add test to test new set_event_notrace_pid file
selftests/ftrace: Add test to test new set_ftrace_notrace_pid file
tracing: Create set_event_notrace_pid to not trace tasks
ftrace: Create set_ftrace_notrace_pid to not trace tasks
ftrace: Make function trace pid filtering a bit more exact
ftrace/kprobe: Show the maxactive number on kprobe_events
tracing: Have the document reflect that the trace file keeps tracing enabled
ring-buffer/tracing: Have iterator acknowledge dropped events
tracing: Do not disable tracing when reading the trace file
ring-buffer: Do not disable recording when there is an iterator
ring-buffer: Make resize disable per cpu buffer instead of total buffer
ring-buffer: Optimize rb_iter_head_event()
ring-buffer: Do not die if rb_iter_peek() fails more than thrice
ring-buffer: Have rb_iter_head_event() handle concurrent writer
ring-buffer: Add page_stamp to iterator for synchronization
ring-buffer: Rename ring_buffer_read() to read_buffer_iter_advance()
ring-buffer: Have ring_buffer_empty() not depend on tracing stopped
tracing: Save off entry when peeking at next entry
...
Show line and column when we got a parse error in bootconfig tool.
Current lib/bootconfig shows the parse error with byte offset, but
that is not human readable.
This makes xbc_init() not showing error message itself but able to
pass the error message and position to caller, so that the caller
can decode it and show the error message with line number and columns.
With this patch, bootconfig tool shows an error with line:column as
below.
$ cat samples/bad-dotword.bconf
# do not start keyword with .
key {
.word = 1
}
$ ./bootconfig -a samples/bad-dotword.bconf initrd
Parse Error: Invalid keyword at 3:3
Link: http://lkml.kernel.org/r/158323469002.10560.4023923847704522760.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Support O=<builddir> option to build bootconfig tool in
the other directory. As same as other tools, if you specify
O=<builddir>, bootconfig command is build under <builddir>.
Link: http://lkml.kernel.org/r/158323468033.10560.14661631369326294355.stgit@devnote2
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add append value operator "+=" support to bootconfig syntax.
With this operator, user can add new value to the key as
an entry of array instead of overwriting.
For example,
foo = bar
...
foo += baz
Then the key "foo" has "bar" and "baz" values as an array.
Link: http://lkml.kernel.org/r/158227283195.12842.8310503105963275584.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Currently, bootconfig adds a new value on the existing key to the tail of an
array. But this looks a bit confusing because an admin can easily rewrite
the original value in the same config file.
This rejects the following value re-definition.
key = value1
...
key = value2
You should rewrite value1 to value2 in this case.
Link: http://lkml.kernel.org/r/158227282199.12842.10110929876059658601.stgit@devnote2
Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ Fixed spelling of arraies to arrays ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reject if a value node is mixed with subkey node on same
parent key node.
A value node can not co-exist with subkey node under some key
node, e.g.
key = value
key.subkey = another-value
This is not be allowed because bootconfig API is not designed
to handle such case.
Link: http://lkml.kernel.org/r/158220115232.26565.7792340045009731803.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Remove error message silent knob, we don't need it anymore
because we can check if there is a bootconfig by checking
the magic word.
If there is a magic word, but failed to load a bootconfig
from initrd, there is a real problem.
Link: http://lkml.kernel.org/r/158220113256.26565.14264598654427773104.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add bootconfig magic word to the end of bootconfig on initrd
image for indicating explicitly the bootconfig is there.
Also tools/bootconfig treats wrong size or wrong checksum or
parse error as an error, because if there is a bootconfig magic
word, there must be a bootconfig.
The bootconfig magic word is "#BOOTCONFIG\n", 12 bytes word.
Thus the block image of the initrd file with bootconfig is
as follows.
[Initrd][bootconfig][size][csum][#BOOTCONFIG\n]
Link: http://lkml.kernel.org/r/158220112263.26565.3944814205960612841.stgit@devnote2
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Suppress non-error messages when applying new bootconfig
to initrd image. To enable it, replace printf for error
message with pr_err() macro.
This also adds a testcase for this fix.
Link: http://lkml.kernel.org/r/158125351377.16911.13283712972275131160.stgit@devnote2
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
To reduce the large static array from kernel data, allocate
xbc_nodes array dynamically only if the kernel loads a
bootconfig.
Note that this also add dummy memblock.h for user-spacae
bootconfig tool.
Link: http://lkml.kernel.org/r/158108569699.3187.6512834527603883707.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Since printk() wrapper macro uses __VA_ARGS__ without "##" prefix, it causes
a build error if there is no variable arguments (e.g. only fmt is
specified.) To fix this error, use ##__VA_ARGS__ instead of __VAR_ARGS__.
Link: http://lkml.kernel.org/r/158108370130.2758.10893830923800978011.stgit@devnote2
Fixes: 950313ebf7 ("tools: bootconfig: Add bootconfig command")
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Show the number of bootconfig nodes when applying new bootconfig to
initrd.
Since there are limitations of bootconfig not only in its filesize,
but also the number of nodes, the number should be shown when applying
so that user can get the feeling of scale of current bootconfig.
Link: http://lkml.kernel.org/r/158091061337.27924.10886706631693823982.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
There are two spelling mistakes in printf statements, fix these.
Link: http://lkml.kernel.org/r/20200116092206.52192-1-colin.king@canonical.com
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add "bootconfig" command which operates the bootconfig
config-data on initrd image.
User can add/delete/verify the boot config on initrd
image using this command.
e.g.
Add a boot config to initrd image
# bootconfig -a myboot.conf /boot/initrd.img
Remove it.
# bootconfig -d /boot/initrd.img
Or verify (and show) it.
# bootconfig /boot/initrd.img
Link: http://lkml.kernel.org/r/157867223582.17873.14342161849213219982.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ Removed extra blank line at end of bootconfig.c ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Linus Torvalds