kernel/git/stable/linux.git/tools/perf/arch/riscv, branch master

perf riscv: fix register name strings

2026-06-10T19:54:41+00:00

On risc-v, pref probe generates an invalid syntax for a named register in a kprobe. $ perf probe --debug verbose --add "n_tty_write tty" ... Writing event: p:probe/n_tty_write _text+8922528 tty=%"%a0":x64 Failed to write event: Invalid argument The problem is the combination of #define REG_DWARFNUM_NAME(reg, idx) [idx] = "%" #reg and entries such as REG_DWARFNUM_NAME("%a0", 10) where #reg will escape the quotes of the first macro parameter. Update the macro definition to produce the correct syntax for a named register in a kprobe, i.e. the unquoted register name with only one leading %. Fixes: a90c4519186dfc08 ("perf riscv: Remove dwarf-regs.c and add dwarf-regs-table.h") Reviewed-by: Ian Rogers Signed-off-by: Martin Kaiser Cc: Ian Rogers Cc: Namhyung Kim Signed-off-by: Arnaldo Carvalho de Melo

perf dwarf: Avoid redefinition warnings for REG_DWARFNUM_NAME

2026-06-10T19:53:35+00:00

dwarf-regs.c includes an arch-specific dwarf-regs-table.h for several architectures. This pulls in different definitions of REG_DWARFNUM_NAME and causes compiler warnings for W=1 builds. In file included from util/dwarf-regs.c:23: .../dwarf-regs-table.h:5: error: "REG_DWARFNUM_NAME" redefined [-Werror] #define REG_DWARFNUM_NAME(reg, idx) [idx] = reg Undefine REG_DWARFNUM_NAME before each new definition. Suggested-by: Arnaldo Carvalho de Melo Signed-off-by: Martin Kaiser Cc: Ian Rogers Cc: Namhyung Kim Signed-off-by: Arnaldo Carvalho de Melo

perf riscv: Fix discarded const qualifier in _get_field()

2026-05-23T22:45:39+00:00

The assignment of strrchr() return values to non-const char * variables triggers a -Werror=discarded-qualifiers warning when building with GCC 14. This happens because in newer glibc versions, strrchr() returns a 'const char *' if the input string is const. Properly declare 'line2' and 'nl' as const char * to match the glibc function signature and ensure type safety. This avoids the need for explicit type casting and aligns with the design pattern of not modifying read-only memory in the perf tool. Reviewed-by: Ian Rogers Signed-off-by: Li Guan Cc: Adrian Hunter Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Signed-off-by: Arnaldo Carvalho de Melo

perf regs: Remove weak attributive archxxx_reg_mask() functions

2026-02-06T15:16:09+00:00

Currently, some architecture-specific perf-regs functions, such as arch__intr_reg_mask() and arch__user_reg_mask(), are defined with the __weak attribute. This approach ensures that only functions matching the architecture of the build/run host are compiled and executed, reducing build time and binary size. However, this __weak attribute restricts these functions to be called only on the same architecture, preventing cross-architecture functionality. For example, a perf.data file captured on x86 cannot be parsed on an ARM platform. To address this limitation, this patch removes the __weak attribute from these perf-regs functions. The architecture-specific code is moved from the arch/ directory to the util/perf-regs-arch/ directory. The appropriate architectural functions are then called based on the EM_HOST. No functional changes are intended. Suggested-by: Ian Rogers Reviewed-by: Ian Rogers Signed-off-by: Dapeng Mi Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Guo Ren Cc: Ingo Molnar Cc: James Clark Cc: John Garry Cc: Mike Leach Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Thomas Falcon Cc: Will Deacon Cc: Xudong Hao Cc: Zide Chen [ Fixed up somme fuzz with s390 and riscv Build files wrt removing perf_regs.o ] Signed-off-by: Arnaldo Carvalho de Melo

perf arch: Update arch headers to use relative UAPI paths

2026-02-06T15:15:48+00:00

The architectural specific headers perf_regs.h currently rely on the host architecture's 'asm/perf_regs.h'. This can lead to compilation inconsistencies or failures when including and building perf for a target architecture that differs from the host's architecture. Explicitly point to the UAPI headers within the tools source tree using relative paths. This ensures that perf is always built against the intended architecture. No functional changes are intended. Reviewed-by: Ian Rogers Signed-off-by: Dapeng Mi Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Guo Ren Cc: Ingo Molnar Cc: James Clark Cc: John Garry Cc: Mike Leach Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Thomas Falcon Cc: Will Deacon Cc: Xudong Hao Cc: Zide Chen Signed-off-by: Arnaldo Carvalho de Melo

perf kvm stat: Remove use of the arch directory

2026-02-03T21:01:27+00:00

`perf kvm stat` supports record and report options. By using the arch directory a report for a different machine type cannot be supported. Move the kvm-stat code out of the arch directory and into util/kvm-stat-arch following the pattern of perf-regs and dwarf-regs. Avoid duplicate symbols by renaming functions to have the architecture name within them. For global variables, wrap them in an architecture specific function. Selecting the architecture to use with `perf kvm stat` is selected by EM_HOST, ie no different than before the change. Later the ELF machine can be determined from the session or a header feature (ie EM_HOST at the time of the record). The build and #define HAVE_KVM_STAT_SUPPORT is now redundant so remove across Makefiles and in the build. Opportunistically constify architectural structs and arrays. Signed-off-by: Ian Rogers Cc: Aditya Bodkhe Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Andrew Jones Cc: Anubhav Shelat Cc: Anup Patel Cc: Athira Rajeev Cc: Blake Jones Cc: Chun-Tse Shao Cc: Dapeng Mi Cc: Dmitriy Vyukov Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Quan Zhou Cc: Shimin Guo Cc: Swapnil Sapkal Cc: Thomas Falcon Cc: Will Deacon Cc: Yunseong Kim Signed-off-by: Arnaldo Carvalho de Melo

perf regs: Refactor use of arch__sample_reg_masks() to perf_reg_name()

2026-01-23T19:58:39+00:00

arch__sample_reg_masks isn't supported on ARM(32), csky, loongarch, MIPS, RISC-V and s390. The table returned by the function just has the name of a register paired with the corresponding sample_regs_user mask value. For a given perf register we can compute the name with perf_reg_name and the mask is just 1 left-shifted by the perf register number. Change __parse_regs to use this method for finding registers rather than arch__sample_reg_masks, thereby adding __parse_regs support for ARM(32), csky, loongarch, MIPS, RISC-V and s390. As arch__sample_reg_masks is then unused, remove the now unneeded declarations. Signed-off-by: Ian Rogers Tested-by: Thomas Richter Cc: Aditya Bodkhe Cc: Adrian Hunter Cc: Albert Ou Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Athira Rajeev Cc: Chun-Tse Shao Cc: Dapeng Mi Cc: Dmitriy Vyukov Cc: Dr. David Alan Gilbert Cc: Guo Ren Cc: Haibo Xu Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Krzysztof Łopatowski Cc: Leo Yan Cc: Namhyung Kim Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Sergei Trofimovich Cc: Shimin Guo Cc: Stephen Brennan Cc: Thomas Falcon Cc: Will Deacon Signed-off-by: Arnaldo Carvalho de Melo

perf unwind-libdw: Fix a cross-arch unwinding bug

2026-01-20T16:00:39+00:00

The set_initial_registers field of Dwfl_Thread_Callbacks needs to be set according to the arch of the stack samples being analyzed, not the arch that perf itself is built for. Currently perf fails to unwind stack samples collected from archs different from that of the host perf is running on. This patch moves the arch-specific implementations of set_initial_registers from tools/perf/arch to tools/perf/utli/unwind-libdw-arch, similar to the way the perf-regs-arch folder contains arch-specific functions related to registers, and chooses the implementation based on the arch of the data being processed. Reviewed-by: Ian Rogers Signed-off-by: Shimin Guo Acked-by: Namhyung Kim Cc: Aditya Bodkhe Cc: Adrian Hunter Cc: Albert Ou Cc: Alexandre Ghiti Cc: Andi Kleen Cc: Athira Rajeev Cc: Chun-Tse Shao Cc: Dmitriy Vyukov Cc: Dr. David Alan Gilbert Cc: Guo Ren Cc: Haibo Xu Cc: Howard Chu Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: John Garry Cc: Krzysztof Łopatowski Cc: Leo Yan Cc: Mark Wielaard Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: Sergei Trofimovich Cc: Stephen Brennan Cc: Thomas Falcon Cc: Will Deacon Signed-off-by: Ian Rogers Signed-off-by: Arnaldo Carvalho de Melo

RISC-V: perf/kvm: Add reporting of interrupt events

2025-07-28T16:58:25+00:00

For `perf kvm stat` on the RISC-V, in order to avoid the occurrence of `UNKNOWN` event names, interrupts should be reported in addition to exceptions. testing without patch: Event name Samples Sample% Time(ns) --------------------------- -------- -------- ------------ STORE_GUEST_PAGE_FAULT 1496461 53.00% 889612544 UNKNOWN 887514 31.00% 272857968 LOAD_GUEST_PAGE_FAULT 305164 10.00% 189186331 VIRTUAL_INST_FAULT 70625 2.00% 134114260 SUPERVISOR_SYSCALL 32014 1.00% 58577110 INST_GUEST_PAGE_FAULT 1 0.00% 2545 testing with patch: Event name Samples Sample% Time(ns) --------------------------- -------- -------- ------------ IRQ_S_TIMER 211271 58.00% 738298680600 EXC_STORE_GUEST_PAGE_FAULT 111279 30.00% 130725914800 EXC_LOAD_GUEST_PAGE_FAULT 22039 6.00% 25441480600 EXC_VIRTUAL_INST_FAULT 8913 2.00% 21015381600 IRQ_VS_EXT 4748 1.00% 10155464300 IRQ_S_EXT 2802 0.00% 13288775800 IRQ_S_SOFT 1998 0.00% 4254129300 Signed-off-by: Quan Zhou Reviewed-by: Andrew Jones Link: https://lore.kernel.org/r/9693132df4d0f857b8be3a75750c36b40213fcc0.1726211632.git.zhouquan@iscas.ac.cn Signed-off-by: Anup Patel

perf build: Remove Makefile.syscalls

2025-03-21T05:58:20+00:00

Now a single beauty file is generated and used by all architectures, remove the per-architecture Makefiles, Kbuild files and previous generator script. Note: there was conversation with Charlie Jenkins and they'd written an alternate approach to support multiple architectures: https://lore.kernel.org/all/20250114-perf_syscall_arch_runtime-v1-1-5b304e408e11@rivosinc.com/ It would have been better to have helped Charlie fix their series (my apologies) but they agreed that the approach taken here was likely best for longer term maintainability: https://lore.kernel.org/lkml/Z6Jk_UN9i69QGqUj@ghost/ Signed-off-by: Ian Rogers Reviewed-by: Howard Chu Reviewed-by: Charlie Jenkins Reviewed-by: Namhyung Kim Acked-by: Arnaldo Carvalho de Melo Link: https://lore.kernel.org/r/20250319050741.269828-11-irogers@google.com Signed-off-by: Namhyung Kim