linux/samples
Linus Torvalds d579c468d7 tracing updates for 6.4:
- User events are finally ready!
   After lots of collaboration between various parties, we finally locked
   down on a stable interface for user events that can also work with user
   space only tracing. This is implemented by telling the kernel (or user
   space library, but that part is user space only and not part of this
   patch set), where the variable is that the application uses to know if
   something is listening to the trace. There's also an interface to tell
   the kernel about these events, which will show up in the
   /sys/kernel/tracing/events/user_events/ directory, where it can be
    enabled. When it's enabled, the kernel will update the variable, to tell
   the application to start writing to the kernel.
   See https://lwn.net/Articles/927595/
 
 - Cleaned up the direct trampolines code to simplify arm64 addition of
   direct trampolines. Direct trampolines use the ftrace interface but
   instead of jumping to the ftrace trampoline, applications (mostly BPF)
   can register their own trampoline for performance reasons.
 
 - Some updates to the fprobe infrastructure. fprobes are more efficient than
   kprobes, as it does not need to save all the registers that kprobes on
   ftrace do. More work needs to be done before the fprobes will be exposed
   as dynamic events.
 
 - More updates to references to the obsolete path of
   /sys/kernel/debug/tracing for the new /sys/kernel/tracing path.
 
 - Add a seq_buf_do_printk() helper to seq_bufs, to print a large buffer line
   by line instead of all at once. There's users in production kernels that
   have a large data dump that originally used printk() directly, but the
   data dump was larger than what printk() allowed as a single print.
   Using seq_buf() to do the printing fixes that.
 
 - Add /sys/kernel/tracing/touched_functions that shows all functions that
   was every traced by ftrace or a direct trampoline. This is used for
   debugging issues where a traced function could have caused a crash by
   a bpf program or live patching.
 
 - Add a "fields" option that is similar to "raw" but outputs the fields of
   the events. It's easier to read by humans.
 
 - Some minor fixes and clean ups.
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Merge tag 'trace-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:

 - User events are finally ready!

   After lots of collaboration between various parties, we finally
   locked down on a stable interface for user events that can also work
   with user space only tracing.

   This is implemented by telling the kernel (or user space library, but
   that part is user space only and not part of this patch set), where
   the variable is that the application uses to know if something is
   listening to the trace.

   There's also an interface to tell the kernel about these events,
   which will show up in the /sys/kernel/tracing/events/user_events/
   directory, where it can be enabled.

   When it's enabled, the kernel will update the variable, to tell the
   application to start writing to the kernel.

   See https://lwn.net/Articles/927595/

 - Cleaned up the direct trampolines code to simplify arm64 addition of
   direct trampolines.

   Direct trampolines use the ftrace interface but instead of jumping to
   the ftrace trampoline, applications (mostly BPF) can register their
   own trampoline for performance reasons.

 - Some updates to the fprobe infrastructure. fprobes are more efficient
   than kprobes, as it does not need to save all the registers that
   kprobes on ftrace do. More work needs to be done before the fprobes
   will be exposed as dynamic events.

 - More updates to references to the obsolete path of
   /sys/kernel/debug/tracing for the new /sys/kernel/tracing path.

 - Add a seq_buf_do_printk() helper to seq_bufs, to print a large buffer
   line by line instead of all at once.

   There are users in production kernels that have a large data dump
   that originally used printk() directly, but the data dump was larger
   than what printk() allowed as a single print.

   Using seq_buf() to do the printing fixes that.

 - Add /sys/kernel/tracing/touched_functions that shows all functions
   that was every traced by ftrace or a direct trampoline. This is used
   for debugging issues where a traced function could have caused a
   crash by a bpf program or live patching.

 - Add a "fields" option that is similar to "raw" but outputs the fields
   of the events. It's easier to read by humans.

 - Some minor fixes and clean ups.

* tag 'trace-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (41 commits)
  ring-buffer: Sync IRQ works before buffer destruction
  tracing: Add missing spaces in trace_print_hex_seq()
  ring-buffer: Ensure proper resetting of atomic variables in ring_buffer_reset_online_cpus
  recordmcount: Fix memory leaks in the uwrite function
  tracing/user_events: Limit max fault-in attempts
  tracing/user_events: Prevent same address and bit per process
  tracing/user_events: Ensure bit is cleared on unregister
  tracing/user_events: Ensure write index cannot be negative
  seq_buf: Add seq_buf_do_printk() helper
  tracing: Fix print_fields() for __dyn_loc/__rel_loc
  tracing/user_events: Set event filter_type from type
  ring-buffer: Clearly check null ptr returned by rb_set_head_page()
  tracing: Unbreak user events
  tracing/user_events: Use print_format_fields() for trace output
  tracing/user_events: Align structs with tabs for readability
  tracing/user_events: Limit global user_event count
  tracing/user_events: Charge event allocs to cgroups
  tracing/user_events: Update documentation for ABI
  tracing/user_events: Use write ABI in example
  tracing/user_events: Add ABI self-test
  ...
2023-04-28 15:57:53 -07:00
..
acrn virt: acrn: Replace obsolete memalign() with posix_memalign() 2023-04-20 14:20:51 +02:00
auxdisplay
binderfs
bpf samples/bpf: sampleip: Replace PAGE_OFFSET with _text address 2023-04-13 21:57:11 -07:00
configfs
connector
coresight
fanotify
fprobe fprobe: Skip exit_handler if entry_handler returns !0 2023-03-28 18:52:22 -04:00
ftrace ftrace: Rename _ftrace_direct_multi APIs to _ftrace_direct APIs 2023-03-21 13:43:32 -04:00
hid samples/hid: Fix spelling mistake "wihout" -> "without" 2022-11-21 22:11:52 +01:00
hidraw
hw_breakpoint
kdb
kfifo
kmemleak kmemleak-test: fix kmemleak_test.c build logic 2023-04-18 16:29:47 -07:00
kobject samples/kobject: make kobj_type structure constant 2023-02-08 13:34:41 +01:00
kprobes samples/kprobes: Add LoongArch support 2023-02-25 22:12:17 +08:00
landlock samples/landlock: Document best-effort approach for LANDLOCK_ACCESS_FS_REFER 2022-11-07 20:49:50 +01:00
livepatch
mei
nitro_enclaves
pidfd
pktgen samples: pktgen: Use "grep -E" instead of "egrep" 2022-11-22 13:23:48 +01:00
qmi soc: qcom: qmi: use const for struct qmi_elem_info 2022-08-29 17:33:01 -05:00
rpmsg
rust rust: macros: take string literals in module! 2022-12-04 01:59:15 +01:00
seccomp
timers
trace_events tracing: Fix cpumask() example typo 2022-12-14 11:17:55 -05:00
trace_printk
uhid
user_events tracing/user_events: Use write ABI in example 2023-03-29 06:52:09 -04:00
v4l treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_168.RULE (part 2) 2022-06-10 14:51:36 +02:00
vfio-mdev Driver core changes for 6.4-rc1 2023-04-27 11:53:57 -07:00
vfs
watch_queue
watchdog
Kconfig - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of 2023-04-27 19:42:02 -07:00
Makefile kmemleak-test: fix kmemleak_test.c build logic 2023-04-18 16:29:47 -07:00