Merge tag 'trace-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux...

Pull tracing updates from Steven Rostedt:
 "The major changes in this tracing update includes:

   - Removal of non-DYNAMIC_FTRACE from 32bit x86

   - Removal of mcount support from x86

   - Emulating a call from int3 on x86_64, fixes live kernel patching

   - Consolidated Tracing Error logs file

  Minor updates:

   - Removal of klp_check_compiler_support()

   - kdb ftrace dumping output changes

   - Accessing and creating ftrace instances from inside the kernel

   - Clean up of #define if macro

   - Introduction of TRACE_EVENT_NOP() to disable trace events based on
     config options

  And other minor fixes and clean ups"

* tag 'trace-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
  x86: Hide the int3_emulate_call/jmp functions from UML
  livepatch: Remove klp_check_compiler_support()
  ftrace/x86: Remove mcount support
  ftrace/x86_32: Remove support for non DYNAMIC_FTRACE
  tracing: Simplify "if" macro code
  tracing: Fix documentation about disabling options using trace_options
  tracing: Replace kzalloc with kcalloc
  tracing: Fix partial reading of trace event's id file
  tracing: Allow RCU to run between postponed startup tests
  tracing: Fix white space issues in parse_pred() function
  tracing: Eliminate const char[] auto variables
  ring-buffer: Fix mispelling of Calculate
  tracing: probeevent: Fix to make the type of $comm string
  tracing: probeevent: Do not accumulate on ret variable
  tracing: uprobes: Re-enable $comm support for uprobe events
  ftrace/x86_64: Emulate call function while updating in breakpoint handler
  x86_64: Allow breakpoints to emulate call instructions
  x86_64: Add gap to int3 to allow for call emulation
  tracing: kdb: Allow ftdump to skip all but the last few entries
  tracing: Add trace_total_entries() / trace_total_entries_cpu()
  ...

diff --cc Documentation/trace/ftrace.rst
Simple merge

diff --cc Documentation/trace/histogram.rst
Simple merge

diff --cc arch/x86/Kconfig
index 326b2d5bab9d73d51f4f07b4597dc100c23fa22b,0544041ae3a25d3a66befa7b7ed33fe7dc247822..21e9f2fac04b545c4d3f8c59691bbd868474779a
--- 1/arch/x86/Kconfig
--- 2/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@@ -29,8 -28,20 +29,19 @@@ config X86_6
        select MODULES_USE_ELF_RELA
        select NEED_DMA_MAP_STATE
        select SWIOTLB
 -      select X86_DEV_DMA_OPS
        select ARCH_HAS_SYSCALL_WRAPPER
  
+ config FORCE_DYNAMIC_FTRACE
+       def_bool y
+       depends on X86_32
+       depends on FUNCTION_TRACER
+       select DYNAMIC_FTRACE
+       help
+        We keep the static function tracing (!DYNAMIC_FTRACE) around
+        in order to test the non static function tracing in the
+        generic code, as other architectures still use it. But we
+        only need to keep it around for x86_64. No need to keep it
+        for x86_32. For x86_32, force DYNAMIC_FTRACE. 
  #
  # Arch settings
  #

diff --cc arch/x86/entry/entry_64.S
index 20e45d9b4e156cc90a464715b0370f27f259ee80,27fcc6fbdd525461b56f13c88b3d1e85f0cce60d..11aa3b2afa4d8e2b3a7d9dc619270d1d8ae15a3d
--- 1/arch/x86/entry/entry_64.S
--- 2/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@@ -878,7 -879,7 +878,7 @@@ apicinterrupt IRQ_WORK_VECTOR                      irq_wor
   * @paranoid == 2 is special: the stub will never switch stacks.  This is for
   * #DF: if the thread stack is somehow unusable, we'll still get a useful OOPS.
   */
- .macro idtentry sym do_sym has_error_code:req paranoid=0 shift_ist=-1 ist_offset=0
 -.macro idtentry sym do_sym has_error_code:req paranoid=0 shift_ist=-1 create_gap=0
++.macro idtentry sym do_sym has_error_code:req paranoid=0 shift_ist=-1 ist_offset=0 create_gap=0
  ENTRY(\sym)
        UNWIND_HINT_IRET_REGS offset=\has_error_code*8
  
@@@ -1128,8 -1143,8 +1142,8 @@@ apicinterrupt3 HYPERV_STIMER0_VECTOR 
        hv_stimer0_callback_vector hv_stimer0_vector_handler
  #endif /* CONFIG_HYPERV */
  
 -idtentry debug                        do_debug                has_error_code=0        paranoid=1 shift_ist=DEBUG_STACK
 +idtentry debug                        do_debug                has_error_code=0        paranoid=1 shift_ist=IST_INDEX_DB ist_offset=DB_STACK_OFFSET
- idtentry int3                 do_int3                 has_error_code=0
+ idtentry int3                 do_int3                 has_error_code=0        create_gap=1
  idtentry stack_segment                do_stack_segment        has_error_code=1
  
  #ifdef CONFIG_XEN_PV

diff --cc arch/x86/include/asm/text-patching.h
index c90678fd391a45d8f48453f48b66fa95b73b89d7,0bbb07eaed6b10ad954a352153336324b1d54659..880b5515b1d6f4b4e1cba06bf07a4a506de76ca9
--- 1/arch/x86/include/asm/text-patching.h
--- 2/arch/x86/include/asm/text-patching.h
+++ b/arch/x86/include/asm/text-patching.h
@@@ -35,11 -35,38 +35,41 @@@ extern void text_poke_early(void *addr
   * inconsistent instruction while you patch.
   */
  extern void *text_poke(void *addr, const void *opcode, size_t len);
 +extern void *text_poke_kgdb(void *addr, const void *opcode, size_t len);
  extern int poke_int3_handler(struct pt_regs *regs);
 -extern void *text_poke_bp(void *addr, const void *opcode, size_t len, void *handler);
 +extern void text_poke_bp(void *addr, const void *opcode, size_t len, void *handler);
  extern int after_bootmem;
 +extern __ro_after_init struct mm_struct *poking_mm;
 +extern __ro_after_init unsigned long poking_addr;
  
+ #ifndef CONFIG_UML_X86
+ static inline void int3_emulate_jmp(struct pt_regs *regs, unsigned long ip)
+ {
+       regs->ip = ip;
+ }
+ 
+ #define INT3_INSN_SIZE 1
+ #define CALL_INSN_SIZE 5
+ 
+ #ifdef CONFIG_X86_64
+ static inline void int3_emulate_push(struct pt_regs *regs, unsigned long val)
+ {
+       /*
+        * The int3 handler in entry_64.S adds a gap between the
+        * stack where the break point happened, and the saving of
+        * pt_regs. We can extend the original stack because of
+        * this gap. See the idtentry macro's create_gap option.
+        */
+       regs->sp -= sizeof(unsigned long);
+       *(unsigned long *)regs->sp = val;
+ }
+ 
+ static inline void int3_emulate_call(struct pt_regs *regs, unsigned long func)
+ {
+       int3_emulate_push(regs, regs->ip - INT3_INSN_SIZE + CALL_INSN_SIZE);
+       int3_emulate_jmp(regs, func);
+ }
+ #endif /* CONFIG_X86_64 */
+ #endif /* !CONFIG_UML_X86 */
+ 
  #endif /* _ASM_X86_TEXT_PATCHING_H */

diff --cc arch/x86/kernel/ftrace.c
Simple merge

diff --cc include/linux/ftrace.h
Simple merge

diff --cc include/trace/events/rcu.h
Simple merge

diff --cc kernel/livepatch/core.c
Simple merge

diff --cc kernel/rcu/rcu.h
Simple merge

diff --cc kernel/rcu/tree.c
Simple merge

diff --cc kernel/trace/ftrace.c
Simple merge

diff --cc kernel/trace/ring_buffer.c
Simple merge

diff --cc kernel/trace/trace.c
Simple merge

diff --cc kernel/trace/trace.h
Simple merge

diff --cc kernel/trace/trace_events_hist.c
Simple merge