linux/Documentation/trace
Linus Torvalds a2ded784cd tracing updates for 6.8:
- Allow kernel trace instance creation to specify what events are created
   Inside the kernel, a subsystem may create a tracing instance that it can
   use to send events to user space. This sub-system may not care about the
   thousands of events that exist in eventfs. Allow the sub-system to specify
   what sub-systems of events it cares about, and only those events are exposed
   to this instance.
 
 - Allow the ring buffer to be broken up into bigger sub-buffers than just the
   architecture page size. A new tracefs file called "buffer_subbuf_size_kb"
   is created. The user can now specify a minimum size the sub-buffer may be
   in kilobytes. Note, that the implementation currently make the sub-buffer
   size a power of 2 pages (1, 2, 4, 8, 16, ...) but the user only writes in
   kilobyte size, and the sub-buffer will be updated to the next size that
   it will can accommodate it. If the user writes in 10, it will change the
   size to be 4 pages on x86 (16K), as that is the next available size that
   can hold 10K pages.
 
 - Update the debug output when a corrupt time is detected in the ring buffer.
   If the ring buffer detects inconsistent timestamps, there's a debug config
   options that will dump the contents of the meta data of the sub-buffer that
   is used for debugging. Add some more information to this dump that helps
   with debugging.
 
 - Add more timestamp debugging checks (only triggers when the config is enabled)
 
 - Increase the trace_seq iterator to 2 page sizes.
 
 - Allow strings written into tracefs_marker to be larger. Up to just under
   2 page sizes (based on what trace_seq can hold).
 
 - Increase the trace_maker_raw write to be as big as a sub-buffer can hold.
 
 - Remove 32 bit time stamp logic, now that the rb_time_cmpxchg() has been
   removed.
 
 - More selftests were added.
 
 - Some code clean ups as well.
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Merge tag 'trace-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:

 - Allow kernel trace instance creation to specify what events are
   created

   Inside the kernel, a subsystem may create a tracing instance that it
   can use to send events to user space. This sub-system may not care
   about the thousands of events that exist in eventfs. Allow the
   sub-system to specify what sub-systems of events it cares about, and
   only those events are exposed to this instance.

 - Allow the ring buffer to be broken up into bigger sub-buffers than
   just the architecture page size.

   A new tracefs file called "buffer_subbuf_size_kb" is created. The
   user can now specify a minimum size the sub-buffer may be in
   kilobytes. Note, that the implementation currently make the
   sub-buffer size a power of 2 pages (1, 2, 4, 8, 16, ...) but the user
   only writes in kilobyte size, and the sub-buffer will be updated to
   the next size that it will can accommodate it. If the user writes in
   10, it will change the size to be 4 pages on x86 (16K), as that is
   the next available size that can hold 10K pages.

 - Update the debug output when a corrupt time is detected in the ring
   buffer. If the ring buffer detects inconsistent timestamps, there's a
   debug config options that will dump the contents of the meta data of
   the sub-buffer that is used for debugging. Add some more information
   to this dump that helps with debugging.

 - Add more timestamp debugging checks (only triggers when the config is
   enabled)

 - Increase the trace_seq iterator to 2 page sizes.

 - Allow strings written into tracefs_marker to be larger. Up to just
   under 2 page sizes (based on what trace_seq can hold).

 - Increase the trace_maker_raw write to be as big as a sub-buffer can
   hold.

 - Remove 32 bit time stamp logic, now that the rb_time_cmpxchg() has
   been removed.

 - More selftests were added.

 - Some code clean ups as well.

* tag 'trace-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (29 commits)
  ring-buffer: Remove stale comment from ring_buffer_size()
  tracing histograms: Simplify parse_actions() function
  tracing/selftests: Remove exec permissions from trace_marker.tc test
  ring-buffer: Use subbuf_order for buffer page masking
  tracing: Update subbuffer with kilobytes not page order
  ringbuffer/selftest: Add basic selftest to test changing subbuf order
  ring-buffer: Add documentation on the buffer_subbuf_order file
  ring-buffer: Just update the subbuffers when changing their allocation order
  ring-buffer: Keep the same size when updating the order
  tracing: Stop the tracing while changing the ring buffer subbuf size
  tracing: Update snapshot order along with main buffer order
  ring-buffer: Make sure the spare sub buffer used for reads has same size
  ring-buffer: Do no swap cpu buffers if order is different
  ring-buffer: Clear pages on error in ring_buffer_subbuf_order_set() failure
  ring-buffer: Read and write to ring buffers with custom sub buffer size
  ring-buffer: Set new size of the ring buffer sub page
  ring-buffer: Add interface for configuring trace sub buffer size
  ring-buffer: Page size per ring buffer
  ring-buffer: Have ring_buffer_print_page_header() be able to access ring_buffer_iter
  ring-buffer: Check if absolute timestamp goes backwards
  ...
2024-01-18 14:35:29 -08:00
..
coresight Documentation: coresight: Add cc_threshold tunable 2023-11-16 11:35:09 +00:00
postprocess mm, vmscan: remove ISOLATE_UNMAPPED 2023-10-04 10:32:29 -07:00
rv Documentation: Fix typos 2023-08-18 11:29:03 -06:00
boottime-trace.rst docs/trace: fix a label of boottime-trace 2021-12-10 13:58:53 -07:00
events-kmem.rst mm/lru: revise the comments of lru_lock 2020-12-15 14:48:04 -08:00
events-msr.rst docs: ftrace: always use canonical ftrace path 2023-01-31 14:02:30 -07:00
events-nmi.rst docs: ftrace: always use canonical ftrace path 2023-01-31 14:02:30 -07:00
events-power.rst PM: QoS: Simplify definitions of CPU latency QoS trace events 2020-02-13 11:26:39 +01:00
events.rst Tracing updates for 6.6: 2023-09-01 16:34:25 -07:00
fprobe.rst Documentation: probes: Add a new ret_ip callback parameter 2023-10-17 10:21:45 +09:00
fprobetrace.rst Documentation: tracing: Add a note about argument and retval access 2023-11-10 19:59:03 +09:00
ftrace-design.rst sh/ftrace: Move arch_ftrace_nmi_{enter,exit} into nmi exception 2020-05-19 15:51:18 +02:00
ftrace-uses.rst Documentation/trace: Fixed typos in the ftrace FLAGS section 2024-01-03 14:15:53 -07:00
ftrace.rst tracing updates for 6.8: 2024-01-18 14:35:29 -08:00
function-graph-fold.vim
hisi-ptt.rst hwtracing: hisi_ptt: Export available filters through sysfs 2023-06-21 11:52:09 +01:00
histogram-design.rst docs: ftrace: always use canonical ftrace path 2023-01-31 14:02:30 -07:00
histogram.rst tracing: Rename stacktrace field to common_stacktrace 2023-05-23 23:38:23 -04:00
hwlat_detector.rst Documentation: Fix typos 2023-08-18 11:29:03 -06:00
index.rst Documentation: tracing/probes: Add fprobe event tracing document 2023-06-06 21:39:56 +09:00
intel_th.rst docs: trace: fix a typo 2020-08-11 10:22:15 -06:00
kprobes.rst docs, kprobes: Add loongarch as supported architecture 2024-01-11 09:36:37 -07:00
kprobetrace.rst Documentation: tracing: Add a note about argument and retval access 2023-11-10 19:59:03 +09:00
mmiotrace.rst docs: ftrace: always use canonical ftrace path 2023-01-31 14:02:30 -07:00
osnoise-tracer.rst Documentation/osnoise: Add osnoise/options documentation 2022-12-10 13:36:05 -05:00
ring-buffer-design.rst docs: trace: ring-buffer-design.rst: use the new SPDX tag 2020-09-24 11:07:44 -06:00
stm.rst Documentation: trace/stm: drop doubled words 2020-07-05 14:40:55 -06:00
sys-t.rst
timerlat-tracer.rst tracing/timerlat: Add user-space interface 2023-06-22 10:39:56 -04:00
tracepoint-analysis.rst docs: ftrace: always use canonical ftrace path 2023-01-31 14:02:30 -07:00
tracepoints.rst tracepoints: Add helper to test if tracepoint is enabled in a header 2020-09-25 18:01:35 -04:00
uprobetracer.rst Documentation: Fix typos 2023-08-18 11:29:03 -06:00
user_events.rst tracing/user_events: Document persist event flags 2023-10-03 22:29:43 -04:00