linux-stable/kernel/trace
Linus Torvalds dd502a8107 This tree introduces static_call(), which is the idea of static_branch()
applied to indirect function calls. Remove a data load (indirection) by
 modifying the text.
 
 They give the flexibility of function pointers, but with better
 performance. (This is especially important for cases where
 retpolines would otherwise be used, as retpolines can be pretty
 slow.)
 
 API overview:
 
   DECLARE_STATIC_CALL(name, func);
   DEFINE_STATIC_CALL(name, func);
   DEFINE_STATIC_CALL_NULL(name, typename);
 
   static_call(name)(args...);
   static_call_cond(name)(args...);
   static_call_update(name, func);
 
 x86 is supported via text patching, otherwise basic indirect calls are used,
 with function pointers.
 
 There's a second variant using inline code patching, inspired by jump-labels,
 implemented on x86 as well.
 
 The new APIs are utilized in the x86 perf code, a heavy user of function pointers,
 where static calls speed up the PMU handler by 4.2% (!).
 
 The generic implementation is not really excercised on other architectures,
 outside of the trivial test_static_call_init() self-test.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'core-static_call-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull static call support from Ingo Molnar:
 "This introduces static_call(), which is the idea of static_branch()
  applied to indirect function calls. Remove a data load (indirection)
  by modifying the text.

  They give the flexibility of function pointers, but with better
  performance. (This is especially important for cases where retpolines
  would otherwise be used, as retpolines can be pretty slow.)

  API overview:

      DECLARE_STATIC_CALL(name, func);
      DEFINE_STATIC_CALL(name, func);
      DEFINE_STATIC_CALL_NULL(name, typename);

      static_call(name)(args...);
      static_call_cond(name)(args...);
      static_call_update(name, func);

  x86 is supported via text patching, otherwise basic indirect calls are
  used, with function pointers.

  There's a second variant using inline code patching, inspired by
  jump-labels, implemented on x86 as well.

  The new APIs are utilized in the x86 perf code, a heavy user of
  function pointers, where static calls speed up the PMU handler by
  4.2% (!).

  The generic implementation is not really excercised on other
  architectures, outside of the trivial test_static_call_init()
  self-test"

* tag 'core-static_call-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  static_call: Fix return type of static_call_init
  tracepoint: Fix out of sync data passing by static caller
  tracepoint: Fix overly long tracepoint names
  x86/perf, static_call: Optimize x86_pmu methods
  tracepoint: Optimize using static_call()
  static_call: Allow early init
  static_call: Add some validation
  static_call: Handle tail-calls
  static_call: Add static_call_cond()
  x86/alternatives: Teach text_poke_bp() to emulate RET
  static_call: Add simple self-test for static calls
  x86/static_call: Add inline static call implementation for x86-64
  x86/static_call: Add out-of-line static call implementation
  static_call: Avoid kprobes on inline static_call()s
  static_call: Add inline static call infrastructure
  static_call: Add basic static call infrastructure
  compiler.h: Make __ADDRESSABLE() symbol truly unique
  jump_label,module: Fix module lifetime for __jump_label_mod_text_reserved()
  module: Properly propagate MODULE_STATE_COMING failure
  module: Fix up module_notifier return values
  ...
2020-10-12 13:58:15 -07:00
..
blktrace.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
bpf_trace.c module: Fix up module_notifier return values 2020-09-01 09:58:03 +02:00
bpf_trace.h bpf: Use dedicated bpf_trace_printk event instead of trace_printk() 2020-07-13 16:55:49 -07:00
fgraph.c tracing: Define MCOUNT_INSN_SIZE when not defined without direct calls 2020-01-02 21:56:44 -05:00
ftrace.c ftrace: Move RCU is watching check after recursion check 2020-09-29 13:05:10 -04:00
ftrace_internal.h x86/ftrace: Have ftrace trampolines turn read-only at the end of system boot up 2020-05-12 18:24:34 -04:00
Kconfig Tracing updates for 5.8: 2020-06-09 10:06:18 -07:00
kprobe_event_gen_test.c tracing: Add kprobe event command generation test module 2020-01-30 09:46:28 -05:00
Makefile Kbuild updates for v5.9 2020-08-09 14:10:26 -07:00
power-traces.c
preemptirq_delay_test.c tracing: Wait for preempt irq delay thread to execute 2020-05-11 17:00:34 -04:00
ring_buffer.c Tracing updates for 5.9 2020-08-07 18:29:15 -07:00
ring_buffer_benchmark.c sched,tracing: Convert to sched_set_fifo() 2020-07-29 11:43:53 +02:00
rpm-traces.c
synth_event_gen_test.c tracing: Have synthetic event test use raw_smp_processor_id() 2020-02-20 17:43:41 -05:00
trace.c This tree introduces static_call(), which is the idea of static_branch() 2020-10-12 13:58:15 -07:00
trace.h ftrace: Fix ftrace_trace_task return value 2020-08-03 16:12:31 -04:00
trace_benchmark.c trace: Use pr_warn instead of pr_warning 2019-10-18 15:01:57 +02:00
trace_benchmark.h
trace_boot.c tracing/boottime: Fix kprobe multiple events 2020-06-23 21:51:50 -04:00
trace_branch.c tracing: Make struct ring_buffer less ambiguous 2020-01-13 13:19:38 -05:00
trace_clock.c
trace_dynevent.c tracing: Use seq_buf for building dynevent_cmd string 2020-02-01 13:10:15 -05:00
trace_dynevent.h tracing: Remove check_arg() callbacks from dynevent args 2020-02-01 13:09:23 -05:00
trace_entries.h tracing: Make ftrace packed events have align of 1 2020-06-16 21:21:02 -04:00
trace_event_perf.c Merge branch 'perf/urgent' into perf/core, to pick up fixes 2019-10-28 12:38:26 +01:00
trace_events.c module: Fix up module_notifier return values 2020-09-01 09:58:03 +02:00
trace_events_filter.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
trace_events_filter_test.h
trace_events_hist.c tracing: fix double free 2020-09-18 13:16:40 -04:00
trace_events_inject.c tracing: Initialize val to zero in parse_entry of inject code 2020-01-02 19:04:57 -05:00
trace_events_synth.c tracing: Move synthetic events to a separate file 2020-06-01 08:23:22 -04:00
trace_events_trigger.c tracing: Fix event trigger to accept redundant spaces 2020-06-23 21:51:40 -04:00
trace_export.c tracing: Make ftrace packed events have align of 1 2020-06-16 21:21:02 -04:00
trace_functions.c trace: Fix typo in allocate_ftrace_ops()'s comment 2020-06-16 21:21:02 -04:00
trace_functions_graph.c ring-buffer: Rename ring_buffer_read() to read_buffer_iter_advance() 2020-03-19 19:11:19 -04:00
trace_hwlat.c tracing/hwlat: Honor the tracing_cpumask 2020-07-30 19:35:04 -04:00
trace_irqsoff.c tracing: Rename trace_buffer to array_buffer 2020-01-13 13:19:38 -05:00
trace_kdb.c tracing: Rename trace_buffer to array_buffer 2020-01-13 13:19:38 -05:00
trace_kprobe.c maccess: rename probe_user_{read,write} to copy_{from,to}_user_nofault 2020-06-17 10:57:41 -07:00
trace_kprobe_selftest.c
trace_kprobe_selftest.h
trace_mmiotrace.c tracing: Make struct ring_buffer less ambiguous 2020-01-13 13:19:38 -05:00
trace_nop.c
trace_output.c tracing: Make the space reserved for the pid wider 2020-09-18 12:42:11 -04:00
trace_output.h
trace_preemptirq.c lockdep: fix order in trace_hardirqs_off_caller() 2020-09-14 10:08:07 +02:00
trace_printk.c module: Fix up module_notifier return values 2020-09-01 09:58:03 +02:00
trace_probe.c tracing/probe: Fix memleak in fetch_op_data operations 2020-06-16 21:21:02 -04:00
trace_probe.h tracing/probe: Replace zero-length array with flexible-array 2020-06-15 23:08:32 -05:00
trace_probe_tmpl.h
trace_sched_switch.c tracing: Fix sched switch start/stop refcount racy updates 2020-01-30 09:46:10 -05:00
trace_sched_wakeup.c tracing: Make struct ring_buffer less ambiguous 2020-01-13 13:19:38 -05:00
trace_selftest.c tracing: Rename trace_buffer to array_buffer 2020-01-13 13:19:38 -05:00
trace_selftest_dynamic.c
trace_seq.c tracing: Remove unused TRACE_SEQ_BUF_USED 2020-01-21 18:39:54 -05:00
trace_stack.c trace: fix an incorrect __user annotation on stack_trace_sysctl 2020-06-08 10:13:56 -04:00
trace_stat.c tracing: Fix tracing_stat return values in error handling paths 2020-01-24 18:06:48 -05:00
trace_stat.h tracing: Use generic type for comparator function 2019-11-14 13:15:11 -05:00
trace_synth.h tracing: Move synthetic events to a separate file 2020-06-01 08:23:22 -04:00
trace_syscalls.c Tracing updates: 2020-02-06 07:12:11 +00:00
trace_uprobe.c tracing/uprobe: Remove dead code in trace_uprobe_register() 2020-08-03 16:16:46 -04:00
tracing_map.c tracing: Convert local functions in tracing_map.c to static 2020-04-22 22:07:26 -04:00
tracing_map.h