kernel/arch/arm/include/asm/perf_event.h, branch linux-rolling-stable

perf/arm: Drop unused functions

2024-11-14T09:40:00Z

For ARM's implementation, perf_instruction_pointer() and perf_misc_flags() are equivalent to the generic versions in include/linux/perf_event.h so arch/arm doesn't need to provide its own versions. Drop them here. Signed-off-by: Colton Lewis Signed-off-by: Ingo Molnar Reviewed-by: Oliver Upton Acked-by: Will Deacon Link: https://lore.kernel.org/r/20241113190156.2145593-2-coltonlewis@google.com

ARM: 9251/1: perf: Fix stacktraces for tracepoint events in THUMB2 kernels

2022-11-07T14:16:43Z

Store the frame address where arm_get_current_stackframe() looks for it (ARM_r7 instead of ARM_fp if CONFIG_THUMB2_KERNEL=y). Otherwise frame->fp gets set to 0, causing unwind_frame() to fail. # bpftrace -e 't:sched:sched_switch { @[kstack] = count(); exit(); }' Attaching 1 probe... @[ __schedule+1059 ]: 1 A typical first unwind instruction is 0x97 (SP = R7), so after executing it SP ends up being 0 and -URC_FAILURE is returned. unwind_frame(pc = ac9da7d7 lr = 00000000 sp = c69bdda0 fp = 00000000) unwind_find_idx(ac9da7d7) unwind_exec_insn: insn = 00000097 unwind_exec_insn: fp = 00000000 sp = 00000000 lr = 00000000 pc = 00000000 With this patch: # bpftrace -e 't:sched:sched_switch { @[kstack] = count(); exit(); }' Attaching 1 probe... @[ __schedule+1059 __schedule+1059 schedule+79 schedule_hrtimeout_range_clock+163 schedule_hrtimeout_range+17 ep_poll+471 SyS_epoll_wait+111 sys_epoll_pwait+231 __ret_fast_syscall+1 ]: 1 Link: https://lore.kernel.org/r/20220920230728.2617421-1-tnovak@fb.com/ Reviewed-by: Linus Walleij Signed-off-by: Tomislav Novak Signed-off-by: Russell King (Oracle)

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55Z

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

arm: perf: Fix callchain parse error with kernel tracepoint events

2015-05-27T15:12:05Z

For ARM, when tracing with tracepoint events, the IP and cpsr are set to 0, preventing the perf code parsing the callchain and resolving the symbols correctly. ./perf record -e sched:sched_switch -g --call-graph dwarf ls [ perf record: Captured and wrote 0.006 MB perf.data ] ./perf report -f Samples: 5 of event 'sched:sched_switch', Event count (approx.): 5 Children Self Command Shared Object Symbol 100.00% 100.00% ls [unknown] [.] 00000000 The fix is to implement perf_arch_fetch_caller_regs for ARM, which fills several necessary registers used for callchain unwinding, including pc,sp, fp and cpsr. With this patch, callchain can be parsed correctly as : ..... - 100.00% 100.00% ls [kernel.kallsyms] [k] __sched_text_start + __sched_text_start + 20.00% 0.00% ls libc-2.18.so [.] _dl_addr + 20.00% 0.00% ls libc-2.18.so [.] write ..... Jean Pihet found this in ARM and come up with a patch: http://thread.gmane.org/gmane.linux.kernel/1734283/focus=1734280 This patch rewrite Jean's patch in C. Signed-off-by: Hou Pengyang Signed-off-by: Will Deacon

arm: perf: factor out callchain code

2014-10-30T12:16:58Z

The ARM callchain handling code is currently bundled with the ARM PMU management code, despite the two having no dependency on each other. This bundling has the unfortunate property of making callchain handling depend on CONFIG_HW_PERF_EVENTS, even though the callchain handling could be applied to software events in the absence of PMU hardware support. This patch separates the two, placing the callchain handling in perf_callchain.c and making it depend on CONFIG_PERF_EVENTS rather than CONFIG_HW_PERF_EVENTS, enabling callchain recording on kernels built without hardware perf event support. Signed-off-by: Mark Rutland Reviewed-by: Will Deacon Signed-off-by: Will Deacon

arm: perf: move event map macros to pmu.h

2014-07-02T14:46:37Z

A few PMU-related macros are now looking a little lonely in asm/perf_event.h now that all other PMU-specific structs, function prototypes and macros live in pmu.h. So as to make their placement consistent and to make it easier to build atop of the current PMU functionality, let's reunite the entire family in pmu.h Acked-by: Will Deacon Tested-by: Christopher Covington Signed-off-by: Mark Rutland Signed-off-by: Will Deacon

ARM: 7584/1: perf: fix link error when CONFIG_HW_PERF_EVENTS is not selected

2012-11-23T13:01:30Z

Commit e50c541 (ARM: perf: add guest vs host discrimination) broken the link as perf_instruction_pointer and perf_misc_flags are not defined when CONFIG_HW_PERF_EVENTS is not selected. As it make little sense to try and profile a guest without any HW event, just fallback to the original code when this config option is not selected. Reported-by: Russell King Acked-by: Will Deacon Signed-off-by: Marc Zyngier Signed-off-by: Russell King

ARM: perf: add guest vs host discrimination

2012-11-09T11:37:24Z

Add minimal guest support to perf, so it can distinguish whether the PMU interrupt was in the host or the guest, as well as collecting some very basic information (guest PC, user vs kernel mode). This is not feature complete though, as it doesn't support backtracing in the guest. Based on the x86 implementation, tested with KVM/ARM. Signed-off-by: Marc Zyngier Signed-off-by: Will Deacon

ARM: perf: prepare for moving CPU PMU code into separate file

2012-08-23T10:35:52Z

The CPU PMU code is tightly coupled with generic ARM PMU handling code. This makes it cumbersome when trying to add support for other ARM PMUs (e.g. interconnect, L2 cache controller, bus) as the generic parts of the code are not readily reusable. This patch cleans up perf_event.c so that reusable code is exposed via header files to other potential PMU drivers. The CPU code is consistently named to identify it as such and also to prepare for moving it into a separate file. Signed-off-by: Will Deacon

ARM: 7448/1: perf: remove arm_perf_pmu_ids global enumeration

2012-07-09T16:41:10Z

In order to provide PMU name strings compatible with the OProfile user ABI, an enumeration of all PMUs is currently used by perf to identify each PMU uniquely. Unfortunately, this does not scale well in the presence of multiple PMUs and creates a single, global namespace across all PMUs in the system. This patch removes the enumeration and instead uses the name string for the PMU to map onto the OProfile variant. perf_pmu_name is implemented for CPU PMUs, which is all that OProfile cares about anyway. Signed-off-by: Will Deacon Signed-off-by: Russell King