linux.git/samples/ftrace, branch v6.18.21 Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git samples/ftrace: Adjust LoongArch register restore order in direct calls 2026-01-08T09:17:11+00:00 Chenghao Duan duanchenghao@kylinos.cn 2025-12-31T07:19:25+00:00 7d7010f5f0ee21dffeaad375949b2c7d431a2496 commit bb85d206be208bbf834883e948125a35ac59993a upstream. Ensure that in the ftrace direct call logic, the CPU register state (with ra = parent return address) is restored to the correct state after the execution of the custom trampoline function and before returning to the traced function. Additionally, guarantee the correctness of the jump logic for jr t0 (traced function address). Cc: stable@vger.kernel.org Fixes: 9cdc3b6a299c ("LoongArch: ftrace: Add direct call support") Reported-by: Youling Tang <tangyouling@kylinos.cn> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Chenghao Duan <duanchenghao@kylinos.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit bb85d206be208bbf834883e948125a35ac59993a upstream.

Ensure that in the ftrace direct call logic, the CPU register state
(with ra = parent return address) is restored to the correct state after
the execution of the custom trampoline function and before returning to
the traced function. Additionally, guarantee the correctness of the jump
logic for jr t0 (traced function address).

Cc: stable@vger.kernel.org
Fixes: 9cdc3b6a299c ("LoongArch: ftrace: Add direct call support")
Reported-by: Youling Tang <tangyouling@kylinos.cn>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Chenghao Duan <duanchenghao@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ftrace/samples: Fix function size computation 2025-09-05T22:39:12+00:00 Vladimir Riabchun ferr.lambarginio@gmail.com 2025-08-26T16:16:46+00:00 80d03a40837a9b26750a25122b906c052cc846c9 In my_tramp1 function .size directive was placed above ASM_RET instruction, leading to a wrong function size. Link: https://lore.kernel.org/aK3d7vxNcO52kEmg@vova-pc Fixes: 9d907f1ae80b ("samples/ftrace: Fix asm function ELF annotations") Signed-off-by: Vladimir Riabchun <ferr.lambarginio@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> 
In my_tramp1 function .size directive was placed above
ASM_RET instruction, leading to a wrong function size.

Link: https://lore.kernel.org/aK3d7vxNcO52kEmg@vova-pc
Fixes: 9d907f1ae80b ("samples/ftrace: Fix asm function ELF annotations")
Signed-off-by: Vladimir Riabchun <ferr.lambarginio@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
tracing: samples: Initialize trace_array_printk() with the correct function 2025-05-12T17:07:22+00:00 Steven Rostedt rostedt@goodmis.org 2025-05-09T19:26:57+00:00 1b0c192c92ea1fe2dcb178f84adf15fe37c3e7c8 When using trace_array_printk() on a created instance, the correct function to use to initialize it is: trace_array_init_printk() Not trace_printk_init_buffer() The former is a proper function to use, the latter is for initializing trace_printk() and causes the NOTICE banner to be displayed. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Divya Indi <divya.indi@oracle.com> Link: https://lore.kernel.org/20250509152657.0f6744d9@gandalf.local.home Fixes: 89ed42495ef4a ("tracing: Sample module to demonstrate kernel access to Ftrace instances.") Fixes: 38ce2a9e33db6 ("tracing: Add trace_array_init_printk() to initialize instance trace_printk() buffers") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> 
When using trace_array_printk() on a created instance, the correct
function to use to initialize it is:

  trace_array_init_printk()

Not

  trace_printk_init_buffer()

The former is a proper function to use, the latter is for initializing
trace_printk() and causes the NOTICE banner to be displayed.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Divya Indi <divya.indi@oracle.com>
Link: https://lore.kernel.org/20250509152657.0f6744d9@gandalf.local.home
Fixes: 89ed42495ef4a ("tracing: Sample module to demonstrate kernel access to Ftrace instances.")
Fixes: 38ce2a9e33db6 ("tracing: Add trace_array_init_printk() to initialize instance trace_printk() buffers")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
treewide: Switch/rename to timer_delete[_sync]() 2025-04-05T08:30:12+00:00 Thomas Gleixner tglx@linutronix.de 2025-04-05T08:17:26+00:00 8fa7292fee5c5240402371ea89ab285ec856c916 timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree over and remove the historical wrapper inlines. Conversion was done with coccinelle plus manual fixups where necessary. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> 
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.

Conversion was done with coccinelle plus manual fixups where necessary.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
samples/ftrace: Add support for ftrace direct samples on powerpc 2024-10-31T00:00:55+00:00 Naveen N Rao naveen@kernel.org 2024-10-30T07:08:49+00:00 71db948b9d2744e92124720f682ed2c26f0de75b Add powerpc 32-bit and 64-bit samples for ftrace direct. This serves to show the sample instruction sequence to be used by ftrace direct calls to adhere to the ftrace ABI. On 64-bit powerpc, TOC setup requires some additional work. Signed-off-by: Naveen N Rao <naveen@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://patch.msgid.link/20241030070850.1361304-17-hbathini@linux.ibm.com 
Add powerpc 32-bit and 64-bit samples for ftrace direct. This serves to
show the sample instruction sequence to be used by ftrace direct calls
to adhere to the ftrace ABI.

On 64-bit powerpc, TOC setup requires some additional work.

Signed-off-by: Naveen N Rao <naveen@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/20241030070850.1361304-17-hbathini@linux.ibm.com
Merge tag 'riscv-for-linus-6.8-mw4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux 2024-01-20T19:06:04+00:00 Linus Torvalds torvalds@linux-foundation.org 2024-01-20T19:06:04+00:00 e5075d8ec5647322fb9e699bfb76331cc8ee098d Pull more RISC-V updates from Palmer Dabbelt: - Support for tuning for systems with fast misaligned accesses. - Support for SBI-based suspend. - Support for the new SBI debug console extension. - The T-Head CMOs now use PA-based flushes. - Support for enabling the V extension in kernel code. - Optimized IP checksum routines. - Various ftrace improvements. - Support for archrandom, which depends on the Zkr extension. - The build is no longer broken under NET=n, KUNIT=y for ports that don't define their own ipv6 checksum. * tag 'riscv-for-linus-6.8-mw4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (56 commits) lib: checksum: Fix build with CONFIG_NET=n riscv: lib: Check if output in asm goto supported riscv: Fix build error on rv32 + XIP riscv: optimize ELF relocation function in riscv RISC-V: Implement archrandom when Zkr is available riscv: Optimize hweight API with Zbb extension riscv: add dependency among Image(.gz), loader(.bin), and vmlinuz.efi samples: ftrace: Add RISC-V support for SAMPLE_FTRACE_DIRECT[_MULTI] riscv: ftrace: Add DYNAMIC_FTRACE_WITH_DIRECT_CALLS support riscv: ftrace: Make function graph use ftrace directly riscv: select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY lib/Kconfig.debug: Update AS_HAS_NON_CONST_LEB128 comment and name riscv: Restrict DWARF5 when building with LLVM to known working versions riscv: Hoist linker relaxation disabling logic into Kconfig kunit: Add tests for csum_ipv6_magic and ip_fast_csum riscv: Add checksum library riscv: Add checksum header riscv: Add static key for misaligned accesses asm-generic: Improve csum_fold RISC-V: selftests: cbo: Ensure asm operands match constraints ... 
Pull more RISC-V updates from Palmer Dabbelt:

 - Support for tuning for systems with fast misaligned accesses.

 - Support for SBI-based suspend.

 - Support for the new SBI debug console extension.

 - The T-Head CMOs now use PA-based flushes.

 - Support for enabling the V extension in kernel code.

 - Optimized IP checksum routines.

 - Various ftrace improvements.

 - Support for archrandom, which depends on the Zkr extension.

 - The build is no longer broken under NET=n, KUNIT=y for ports that
   don't define their own ipv6 checksum.

* tag 'riscv-for-linus-6.8-mw4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (56 commits)
  lib: checksum: Fix build with CONFIG_NET=n
  riscv: lib: Check if output in asm goto supported
  riscv: Fix build error on rv32 + XIP
  riscv: optimize ELF relocation function in riscv
  RISC-V: Implement archrandom when Zkr is available
  riscv: Optimize hweight API with Zbb extension
  riscv: add dependency among Image(.gz), loader(.bin), and vmlinuz.efi
  samples: ftrace: Add RISC-V support for SAMPLE_FTRACE_DIRECT[_MULTI]
  riscv: ftrace: Add DYNAMIC_FTRACE_WITH_DIRECT_CALLS support
  riscv: ftrace: Make function graph use ftrace directly
  riscv: select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY
  lib/Kconfig.debug: Update AS_HAS_NON_CONST_LEB128 comment and name
  riscv: Restrict DWARF5 when building with LLVM to known working versions
  riscv: Hoist linker relaxation disabling logic into Kconfig
  kunit: Add tests for csum_ipv6_magic and ip_fast_csum
  riscv: Add checksum library
  riscv: Add checksum header
  riscv: Add static key for misaligned accesses
  asm-generic: Improve csum_fold
  RISC-V: selftests: cbo: Ensure asm operands match constraints
  ...
samples: ftrace: Add RISC-V support for SAMPLE_FTRACE_DIRECT[_MULTI] 2024-01-18T02:17:10+00:00 Song Shuai suagrfillet@gmail.com 2023-11-30T12:15:31+00:00 629291dd8499e4dc7dff6e9ab8c13b1a841059e8 Add RISC-V variants of the ftrace-direct* samples. Tested-by: Evgenii Shatokhin <e.shatokhin@yadro.com> Signed-off-by: Song Shuai <suagrfillet@gmail.com> Tested-by: Guo Ren <guoren@kernel.org> Signed-off-by: Guo Ren <guoren@kernel.org> Acked-by: Björn Töpel <bjorn@rivosinc.com> Link: https://lore.kernel.org/r/20231130121531.1178502-5-bjorn@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> 
Add RISC-V variants of the ftrace-direct* samples.

Tested-by: Evgenii Shatokhin <e.shatokhin@yadro.com>
Signed-off-by: Song Shuai <suagrfillet@gmail.com>
Tested-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Guo Ren <guoren@kernel.org>
Acked-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20231130121531.1178502-5-bjorn@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
tracing: Allow creating instances with specified system events 2023-12-19T04:14:16+00:00 Steven Rostedt (Google) rostedt@goodmis.org 2023-12-13T14:37:01+00:00 d23569979ca1cd139a42c410e0c7b9e6014c3b3a A trace instance may only need to enable specific events. As the eventfs directory of an instance currently creates all events which adds overhead, allow internal instances to be created with just the events in systems that they care about. This currently only deals with systems and not individual events, but this should bring down the overhead of creating instances for specific use cases quite bit. The trace_array_get_by_name() now has another parameter "systems". This parameter is a const string pointer of a comma/space separated list of event systems that should be created by the trace_array. (Note if the trace_array already exists, this parameter is ignored). The list of systems is saved and if a module is loaded, its events will not be added unless the system for those events also match the systems string. Link: https://lore.kernel.org/linux-trace-kernel/20231213093701.03fddec0@gandalf.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Sean Paul <seanpaul@chromium.org> Cc: Arun Easi <aeasi@marvell.com> Cc: Daniel Wagner <dwagner@suse.de> Tested-by: Dmytro Maluka <dmaluka@chromium.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> 
A trace instance may only need to enable specific events. As the eventfs
directory of an instance currently creates all events which adds overhead,
allow internal instances to be created with just the events in systems
that they care about. This currently only deals with systems and not
individual events, but this should bring down the overhead of creating
instances for specific use cases quite bit.

The trace_array_get_by_name() now has another parameter "systems". This
parameter is a const string pointer of a comma/space separated list of
event systems that should be created by the trace_array. (Note if the
trace_array already exists, this parameter is ignored).

The list of systems is saved and if a module is loaded, its events will
not be added unless the system for those events also match the systems
string.

Link: https://lore.kernel.org/linux-trace-kernel/20231213093701.03fddec0@gandalf.local.home

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Arun Easi   <aeasi@marvell.com>
Cc: Daniel Wagner <dwagner@suse.de>
Tested-by: Dmytro Maluka <dmaluka@chromium.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
samples: ftrace: Replace bti assembly with hint for older compiler 2023-08-22T02:03:58+00:00 GONG, Ruiqi gongruiqi1@huawei.com 2023-08-20T11:15:09+00:00 e332938e6fc8117fb9bb1374339cea879b3972d9 When cross-building the arm64 kernel with allmodconfig using GCC 9.4, the following error occurs on multiple files under samples/ftrace/: /tmp/ccPC1ODs.s: Assembler messages: /tmp/ccPC1ODs.s:8: Error: selected processor does not support `bti c' Fix this issue by replacing `bti c` with `hint 34`, which is compatible for the older compiler. Link: https://lore.kernel.org/linux-trace-kernel/20230820111509.1470826-1-gongruiqi@huaweicloud.com Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Florent Revest <revest@chromium.org> Fixes: 8c3526fb86060cb5 ("arm64: ftrace: Add direct call trampoline samples support") Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> 
When cross-building the arm64 kernel with allmodconfig using GCC 9.4,
the following error occurs on multiple files under samples/ftrace/:

/tmp/ccPC1ODs.s: Assembler messages:
/tmp/ccPC1ODs.s:8: Error: selected processor does not support `bti c'

Fix this issue by replacing `bti c` with `hint 34`, which is compatible
for the older compiler.

Link: https://lore.kernel.org/linux-trace-kernel/20230820111509.1470826-1-gongruiqi@huaweicloud.com

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Florent Revest <revest@chromium.org>
Fixes: 8c3526fb86060cb5 ("arm64: ftrace: Add direct call trampoline samples support")
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
arm64: ftrace: Add direct call trampoline samples support 2023-07-10T21:51:54+00:00 Florent Revest revest@chromium.org 2023-04-27T14:07:00+00:00 8c3526fb86060cb53a1f4ca6cc44eb036afcf43e The ftrace samples need per-architecture trampoline implementations to save and restore argument registers around the calls to my_direct_func* and to restore polluted registers (eg: x30). These samples also include <asm/asm-offsets.h> which, on arm64, is not necessary and redefines previously defined macros (resulting in warnings) so these includes are guarded by !CONFIG_ARM64. Link: https://lkml.kernel.org/r/20230427140700.625241-3-revest@chromium.org Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Florent Revest <revest@chromium.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> 
The ftrace samples need per-architecture trampoline implementations
to save and restore argument registers around the calls to
my_direct_func* and to restore polluted registers (eg: x30).

These samples also include <asm/asm-offsets.h> which, on arm64, is not
necessary and redefines previously defined macros (resulting in
warnings) so these includes are guarded by !CONFIG_ARM64.

Link: https://lkml.kernel.org/r/20230427140700.625241-3-revest@chromium.org

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Florent Revest <revest@chromium.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>