This series extends the recently introduced trace remotes
infrastructure, bringing useful features for developers:

  * dump_on_oops: Dump the trace remote buffer on system panic.
  * printk: Redirect remote events to dmesg.
  * trace_remote=: Configure a trace_remote from the commandline.

It also brings a couple of optimisations:

  * Header compressed length support for small events.
  * Single work thread for remote polling.

And some misc improvements:

  * Use kstrtobool where possible
  * Fix trace remote unregistering

I didn't put a "Fixes:" tag on the commit which is fixing the remote
registration because I do not believe this is something any user can
trigger.

Vincent Donnefort (13):
  tracing/remotes: Release tracefs,eventfs on registration failure
  tracing/remotes: Use kstrtobool for boolean tracefs files
  tracing/remotes: Use a single per-remote polling work
  tracing/simple_ring_buffer: Add support for compressed length
  tracing/remotes: Add printk tracefs file
  tracing/remotes: selftests: Add a test for the printk tracefs file
  tracing/remotes: selftests: Prefix hypervisor folder
  ring-buffer: Add ring_buffer_read_remote_meta_page()
  tracing/remotes: Add dump_on_oops tracefs file
  tracing/remotes: selftests: Add a test for the dump_on_oops tracefs
    file
  Documentation: tracing/remotes: Add detailed tracefs layout
  tracing/remotes: Add trace_remote cmdline options
  Documentation/kernel-parameters: Add trace_remote

 .../admin-guide/kernel-parameters.txt         |  16 +
 Documentation/trace/remotes.rst               |  63 +-
 include/linux/ring_buffer.h                   |   1 +
 kernel/trace/ring_buffer.c                    |  53 ++
 kernel/trace/simple_ring_buffer.c             |  22 +-
 kernel/trace/trace_remote.c                   | 649 +++++++++++++++---
 .../buffer_size.tc                            |   0
 .../remotes/00hypervisor/dump_on_oops.tc      |  11 +
 .../{hypervisor => 00hypervisor}/hotplug.tc   |   0
 .../test.d/remotes/00hypervisor/printk.tc     |  11 +
 .../{hypervisor => 00hypervisor}/reset.tc     |   0
 .../{hypervisor => 00hypervisor}/trace.tc     |   0
 .../trace_pipe.tc                             |   0
 .../{hypervisor => 00hypervisor}/unloading.tc |   0
 .../ftrace/test.d/remotes/dump_on_oops.tc     |  51 ++
 .../selftests/ftrace/test.d/remotes/functions |   2 +
 .../selftests/ftrace/test.d/remotes/printk.tc |  72 ++
 17 files changed, 847 insertions(+), 104 deletions(-)
 rename tools/testing/selftests/ftrace/test.d/remotes/{hypervisor => 00hypervisor}/buffer_size.tc (100%)
 create mode 100644 tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/dump_on_oops.tc
 rename tools/testing/selftests/ftrace/test.d/remotes/{hypervisor => 00hypervisor}/hotplug.tc (100%)
 create mode 100644 tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/printk.tc
 rename tools/testing/selftests/ftrace/test.d/remotes/{hypervisor => 00hypervisor}/reset.tc (100%)
 rename tools/testing/selftests/ftrace/test.d/remotes/{hypervisor => 00hypervisor}/trace.tc (100%)
 rename tools/testing/selftests/ftrace/test.d/remotes/{hypervisor => 00hypervisor}/trace_pipe.tc (100%)
 rename tools/testing/selftests/ftrace/test.d/remotes/{hypervisor => 00hypervisor}/unloading.tc (100%)
 create mode 100644 tools/testing/selftests/ftrace/test.d/remotes/dump_on_oops.tc
 create mode 100644 tools/testing/selftests/ftrace/test.d/remotes/printk.tc


base-commit: e43ffb69e0438cddd72aaa30898b4dc446f664f8
-- 
2.54.0.1032.g2f8565e1d1-goog

Avoid interleaving run tests by prefixing the hypervisor folder.

Signed-off-by: Vincent Donnefort <vdonnefort@google.com>

diff --git a/tools/testing/selftests/ftrace/test.d/remotes/hypervisor/buffer_size.tc b/tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/buffer_size.tc
similarity index 100%
rename from tools/testing/selftests/ftrace/test.d/remotes/hypervisor/buffer_size.tc
rename to tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/buffer_size.tc
diff --git a/tools/testing/selftests/ftrace/test.d/remotes/hypervisor/hotplug.tc b/tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/hotplug.tc
similarity index 100%
rename from tools/testing/selftests/ftrace/test.d/remotes/hypervisor/hotplug.tc
rename to tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/hotplug.tc
diff --git a/tools/testing/selftests/ftrace/test.d/remotes/hypervisor/printk.tc b/tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/printk.tc
similarity index 100%
rename from tools/testing/selftests/ftrace/test.d/remotes/hypervisor/printk.tc
rename to tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/printk.tc
diff --git a/tools/testing/selftests/ftrace/test.d/remotes/hypervisor/reset.tc b/tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/reset.tc
similarity index 100%
rename from tools/testing/selftests/ftrace/test.d/remotes/hypervisor/reset.tc
rename to tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/reset.tc
diff --git a/tools/testing/selftests/ftrace/test.d/remotes/hypervisor/trace.tc b/tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/trace.tc
similarity index 100%
rename from tools/testing/selftests/ftrace/test.d/remotes/hypervisor/trace.tc
rename to tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/trace.tc
diff --git a/tools/testing/selftests/ftrace/test.d/remotes/hypervisor/trace_pipe.tc b/tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/trace_pipe.tc
similarity index 100%
rename from tools/testing/selftests/ftrace/test.d/remotes/hypervisor/trace_pipe.tc
rename to tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/trace_pipe.tc
diff --git a/tools/testing/selftests/ftrace/test.d/remotes/hypervisor/unloading.tc b/tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/unloading.tc
similarity index 100%
rename from tools/testing/selftests/ftrace/test.d/remotes/hypervisor/unloading.tc
rename to tools/testing/selftests/ftrace/test.d/remotes/00hypervisor/unloading.tc
-- 
2.54.0.1032.g2f8565e1d1-goog