Go to file
Linus Torvalds aa1a8ce533 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 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
  ...
2020-04-05 10:36:18 -07:00
arch This is the bulk of GPIO development for the v5.7 kernel cycle. 2020-04-04 10:27:00 -07:00
block SCSI misc on 20200402 2020-04-02 17:03:53 -07:00
certs .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2020-04-01 14:47:40 -07:00
Documentation New tracing features: 2020-04-05 10:36:18 -07:00
drivers New tracing features: 2020-04-05 10:36:18 -07:00
fs Merge branch 'work.exfat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-04-04 11:46:09 -07:00
include New tracing features: 2020-04-05 10:36:18 -07:00
init New tracing features: 2020-04-05 10:36:18 -07:00
ipc Revert "ipc,sem: remove uneeded sem_undo_list lock usage in exit_sem()" 2020-02-21 11:22:15 -08:00
kernel New tracing features: 2020-04-05 10:36:18 -07:00
lib New tracing features: 2020-04-05 10:36:18 -07:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm drm: add support for hugepages to TTM 2020-04-04 11:58:55 -07:00
net Keyrings fixes 2020-04-04 12:24:47 -07:00
samples SPDX patches for 5.7-rc1. 2020-04-03 13:12:26 -07:00
scripts Char/Misc driver patches for 5.7-rc1 2020-04-03 13:22:40 -07:00
security Keyrings fixes 2020-04-04 12:24:47 -07:00
sound SPDX patches for 5.7-rc1. 2020-04-03 13:12:26 -07:00
tools New tracing features: 2020-04-05 10:36:18 -07:00
usr .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
virt KVM: Pass kvm_init()'s opaque param to additional arch funcs 2020-03-31 10:48:03 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2020-03-06 21:50:05 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
.mailmap media updates for v5.7-rc1 2020-03-30 13:42:05 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Hand MIPS over to Thomas 2020-02-24 22:43:18 -08:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS Merge branch 'work.exfat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-04-04 11:46:09 -07:00
Makefile Kbuild updates for v5.7 2020-03-31 16:03:39 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.