diff options
Diffstat (limited to 'arch/riscv/kernel/ftrace.c')
| -rw-r--r-- | arch/riscv/kernel/ftrace.c | 44 |
1 files changed, 40 insertions, 4 deletions
diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c index f5aa24d9e1c1..4f4987a6d83d 100644 --- a/arch/riscv/kernel/ftrace.c +++ b/arch/riscv/kernel/ftrace.c @@ -8,6 +8,7 @@ #include <linux/ftrace.h> #include <linux/uaccess.h> #include <linux/memory.h> +#include <linux/stop_machine.h> #include <asm/cacheflush.h> #include <asm/patch.h> @@ -75,8 +76,7 @@ static int __ftrace_modify_call(unsigned long hook_pos, unsigned long target, make_call_t0(hook_pos, target, call); /* Replace the auipc-jalr pair at once. Return -EPERM on write error. */ - if (patch_text_nosync - ((void *)hook_pos, enable ? call : nops, MCOUNT_INSN_SIZE)) + if (patch_insn_write((void *)hook_pos, enable ? call : nops, MCOUNT_INSN_SIZE)) return -EPERM; return 0; @@ -88,7 +88,7 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) make_call_t0(rec->ip, addr, call); - if (patch_text_nosync((void *)rec->ip, call, MCOUNT_INSN_SIZE)) + if (patch_insn_write((void *)rec->ip, call, MCOUNT_INSN_SIZE)) return -EPERM; return 0; @@ -99,7 +99,7 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, { unsigned int nops[2] = {NOP4, NOP4}; - if (patch_text_nosync((void *)rec->ip, nops, MCOUNT_INSN_SIZE)) + if (patch_insn_write((void *)rec->ip, nops, MCOUNT_INSN_SIZE)) return -EPERM; return 0; @@ -134,6 +134,42 @@ int ftrace_update_ftrace_func(ftrace_func_t func) return ret; } + +struct ftrace_modify_param { + int command; + atomic_t cpu_count; +}; + +static int __ftrace_modify_code(void *data) +{ + struct ftrace_modify_param *param = data; + + if (atomic_inc_return(¶m->cpu_count) == num_online_cpus()) { + ftrace_modify_all_code(param->command); + /* + * Make sure the patching store is effective *before* we + * increment the counter which releases all waiting CPUs + * by using the release variant of atomic increment. The + * release pairs with the call to local_flush_icache_all() + * on the waiting CPU. + */ + atomic_inc_return_release(¶m->cpu_count); + } else { + while (atomic_read(¶m->cpu_count) <= num_online_cpus()) + cpu_relax(); + } + + local_flush_icache_all(); + + return 0; +} + +void arch_ftrace_update_code(int command) +{ + struct ftrace_modify_param param = { command, ATOMIC_INIT(0) }; + + stop_machine(__ftrace_modify_code, ¶m, cpu_online_mask); +} #endif #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS |