projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
| 14f70012 DCZ |
2 | /* |
| 3 | * Linux performance counter support for MIPS. | |
| 4 | * | |
| 5 | * Copyright (C) 2010 MIPS Technologies, Inc. | |
| 6 | * Author: Deng-Cheng Zhu | |
| 7 | * | |
| 8 | * This code is based on the implementation for ARM, which is in turn | |
| 9 | * based on the sparc64 perf event code and the x86 code. Performance | |
| 7e788d96 DCZ |
10 | * counter access is based on the MIPS Oprofile code. And the callchain |
| 11 | * support references the code of MIPS stacktrace.c. | |
| 14f70012 DCZ |
12 | */ |
| 13 | ||
| 14f70012 | 14 | #include <linux/perf_event.h> |
| 68db0cf1 | 15 | #include <linux/sched/task_stack.h> |
| 14f70012 | 16 | |
| 14f70012 | 17 | #include <asm/stacktrace.h> |
| 3a9ab99e | 18 | |
| 7e788d96 | 19 | /* Callchain handling code. */ |
| 7e788d96 DCZ |
20 | |
| 21 | /* | |
| 22 | * Leave userspace callchain empty for now. When we find a way to trace | |
| e5dcb58a | 23 | * the user stack callchains, we will add it here. |
| 7e788d96 | 24 | */ |
| 7e788d96 | 25 | |
| cfbcf468 ACM |
26 | static void save_raw_perf_callchain(struct perf_callchain_entry_ctx *entry, |
| 27 | unsigned long reg29) | |
| 7e788d96 DCZ |
28 | { |
| 29 | unsigned long *sp = (unsigned long *)reg29; | |
| 30 | unsigned long addr; | |
| 31 | ||
| 32 | while (!kstack_end(sp)) { | |
| 33 | addr = *sp++; | |
| 34 | if (__kernel_text_address(addr)) { | |
| 98f92f2f | 35 | perf_callchain_store(entry, addr); |
| 3b1fff08 | 36 | if (entry->nr >= entry->max_stack) |
| 7e788d96 DCZ |
37 | break; |
| 38 | } | |
| 39 | } | |
| 40 | } | |
| 41 | ||
| cfbcf468 ACM |
42 | void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, |
| 43 | struct pt_regs *regs) | |
| 7e788d96 DCZ |
44 | { |
| 45 | unsigned long sp = regs->regs[29]; | |
| 46 | #ifdef CONFIG_KALLSYMS | |
| 47 | unsigned long ra = regs->regs[31]; | |
| 48 | unsigned long pc = regs->cp0_epc; | |
| 49 | ||
| 7e788d96 DCZ |
50 | if (raw_show_trace || !__kernel_text_address(pc)) { |
| 51 | unsigned long stack_page = | |
| 52 | (unsigned long)task_stack_page(current); | |
| 53 | if (stack_page && sp >= stack_page && | |
| 54 | sp <= stack_page + THREAD_SIZE - 32) | |
| 55 | save_raw_perf_callchain(entry, sp); | |
| 56 | return; | |
| 57 | } | |
| 58 | do { | |
| 98f92f2f | 59 | perf_callchain_store(entry, pc); |
| 3b1fff08 | 60 | if (entry->nr >= entry->max_stack) |
| 7e788d96 DCZ |
61 | break; |
| 62 | pc = unwind_stack(current, &sp, pc, &ra); | |
| 63 | } while (pc); | |
| 64 | #else | |
| 7e788d96 DCZ |
65 | save_raw_perf_callchain(entry, sp); |
| 66 | #endif | |
| 67 | } |