diff options
Diffstat (limited to 'arch/s390/kernel')
| -rw-r--r-- | arch/s390/kernel/asm-offsets.c | 6 | ||||
| -rw-r--r-- | arch/s390/kernel/entry.h | 1 | ||||
| -rw-r--r-- | arch/s390/kernel/ftrace.c | 48 | ||||
| -rw-r--r-- | arch/s390/kernel/mcount.S | 23 |
4 files changed, 20 insertions, 58 deletions
diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c index 862a9140528e..36709112ae7a 100644 --- a/arch/s390/kernel/asm-offsets.c +++ b/arch/s390/kernel/asm-offsets.c @@ -175,12 +175,6 @@ int main(void) DEFINE(OLDMEM_SIZE, PARMAREA + offsetof(struct parmarea, oldmem_size)); DEFINE(COMMAND_LINE, PARMAREA + offsetof(struct parmarea, command_line)); DEFINE(MAX_COMMAND_LINE_SIZE, PARMAREA + offsetof(struct parmarea, max_command_line_size)); -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - /* function graph return value tracing */ - OFFSET(__FGRAPH_RET_GPR2, fgraph_ret_regs, gpr2); - OFFSET(__FGRAPH_RET_FP, fgraph_ret_regs, fp); - DEFINE(__FGRAPH_RET_SIZE, sizeof(struct fgraph_ret_regs)); -#endif OFFSET(__FTRACE_REGS_PT_REGS, __arch_ftrace_regs, regs); DEFINE(__FTRACE_REGS_SIZE, sizeof(struct __arch_ftrace_regs)); diff --git a/arch/s390/kernel/entry.h b/arch/s390/kernel/entry.h index 21969520f947..a1f28879c87e 100644 --- a/arch/s390/kernel/entry.h +++ b/arch/s390/kernel/entry.h @@ -41,7 +41,6 @@ void do_restart(void *arg); void __init startup_init(void); void die(struct pt_regs *regs, const char *str); int setup_profiling_timer(unsigned int multiplier); -unsigned long prepare_ftrace_return(unsigned long parent, unsigned long sp, unsigned long ip); struct s390_mmap_arg_struct; struct fadvise64_64_args; diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c index 51439a71e392..c0b2c97efefb 100644 --- a/arch/s390/kernel/ftrace.c +++ b/arch/s390/kernel/ftrace.c @@ -261,43 +261,23 @@ void ftrace_arch_code_modify_post_process(void) } #ifdef CONFIG_FUNCTION_GRAPH_TRACER -/* - * Hook the return address and push it in the stack of return addresses - * in current thread info. - */ -unsigned long prepare_ftrace_return(unsigned long ra, unsigned long sp, - unsigned long ip) -{ - if (unlikely(ftrace_graph_is_dead())) - goto out; - if (unlikely(atomic_read(¤t->tracing_graph_pause))) - goto out; - ip -= MCOUNT_INSN_SIZE; - if (!function_graph_enter(ra, ip, 0, (void *) sp)) - ra = (unsigned long) return_to_handler; -out: - return ra; -} -NOKPROBE_SYMBOL(prepare_ftrace_return); -/* - * Patch the kernel code at ftrace_graph_caller location. The instruction - * there is branch relative on condition. To enable the ftrace graph code - * block, we simply patch the mask field of the instruction to zero and - * turn the instruction into a nop. - * To disable the ftrace graph code the mask field will be patched to - * all ones, which turns the instruction into an unconditional branch. - */ -int ftrace_enable_ftrace_graph_caller(void) +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct ftrace_regs *fregs) { - /* Expect brc 0xf,... */ - return ftrace_patch_branch_mask(ftrace_graph_caller, 0xa7f4, false); -} + unsigned long *parent = &arch_ftrace_regs(fregs)->regs.gprs[14]; + int bit; -int ftrace_disable_ftrace_graph_caller(void) -{ - /* Expect brc 0x0,... */ - return ftrace_patch_branch_mask(ftrace_graph_caller, 0xa704, true); + if (unlikely(ftrace_graph_is_dead())) + return; + if (unlikely(atomic_read(¤t->tracing_graph_pause))) + return; + bit = ftrace_test_recursion_trylock(ip, *parent); + if (bit < 0) + return; + if (!function_graph_enter_regs(*parent, ip, 0, parent, fregs)) + *parent = (unsigned long)&return_to_handler; + ftrace_test_recursion_unlock(bit); } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S index 7e267ef63a7f..1fec370fecf4 100644 --- a/arch/s390/kernel/mcount.S +++ b/arch/s390/kernel/mcount.S @@ -104,17 +104,6 @@ SYM_CODE_START(ftrace_common) lgr %r3,%r14 la %r5,STACK_FREGS(%r15) BASR_EX %r14,%r1 -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -# The j instruction gets runtime patched to a nop instruction. -# See ftrace_enable_ftrace_graph_caller. -SYM_INNER_LABEL(ftrace_graph_caller, SYM_L_GLOBAL) - j .Lftrace_graph_caller_end - lmg %r2,%r3,(STACK_FREGS_PTREGS_GPRS+14*8)(%r15) - lg %r4,(STACK_FREGS_PTREGS_PSW+8)(%r15) - brasl %r14,prepare_ftrace_return - stg %r2,(STACK_FREGS_PTREGS_GPRS+14*8)(%r15) -.Lftrace_graph_caller_end: -#endif lg %r0,(STACK_FREGS_PTREGS_PSW+8)(%r15) #ifdef MARCH_HAS_Z196_FEATURES ltg %r1,STACK_FREGS_PTREGS_ORIG_GPR2(%r15) @@ -134,14 +123,14 @@ SYM_CODE_END(ftrace_common) SYM_FUNC_START(return_to_handler) stmg %r2,%r5,32(%r15) lgr %r1,%r15 - aghi %r15,-(STACK_FRAME_OVERHEAD+__FGRAPH_RET_SIZE) + # allocate ftrace_regs and stack frame for ftrace_return_to_handler + aghi %r15,-STACK_FRAME_SIZE_FREGS stg %r1,__SF_BACKCHAIN(%r15) - la %r3,STACK_FRAME_OVERHEAD(%r15) - stg %r1,__FGRAPH_RET_FP(%r3) - stg %r2,__FGRAPH_RET_GPR2(%r3) - lgr %r2,%r3 + stg %r2,(STACK_FREGS_PTREGS_GPRS+2*8)(%r15) + stg %r1,(STACK_FREGS_PTREGS_GPRS+15*8)(%r15) + la %r2,STACK_FRAME_OVERHEAD(%r15) brasl %r14,ftrace_return_to_handler - aghi %r15,STACK_FRAME_OVERHEAD+__FGRAPH_RET_SIZE + aghi %r15,STACK_FRAME_SIZE_FREGS lgr %r14,%r2 lmg %r2,%r5,32(%r15) BR_EX %r14 |