From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 080F510A0C; Sun, 15 Sep 2024 08:53:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726390429; cv=none; b=iy1cNPXpun//jdFbQ2hZbAhmue/KdVGEkEz9bJoRXrx4BxJoZa3TxElzqxYskopweadDT1Y+eVj/2DjVBHkaMY2owT0q56GU8nje53XCkBnY05Xc0Kx1HMuoXvHcMi57Jl/bLcAEcjc+P9TheilehOtLddW5NvmFsMcI+0bp52U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726390429; c=relaxed/simple; bh=IUbpLZbmMOf2lfrKeyKMTxotewLTS21gPLHKHW5U1gA=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=SjCskiz4nCjBfT2WhcYoJtfgniKBT6ygQI/9gU9a0OyYFXhbeZzn6NOTkOevHP6RxmXpzGtUVk9Cv4K936BHe3KRiOpELXNkO9L+qJMtMreiPrd+G/W0r1hfbC6awyPTGEb2p/Oyyiqcd1v2HhoEK4/44uxBLWxcHepZSqBN8oE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 108DBC4CEC3; Sun, 15 Sep 2024 08:53:45 +0000 (UTC) Date: Sun, 15 Sep 2024 04:53:41 -0400 From: Steven Rostedt To: Michael Ellerman , linuxppc-dev@lists.ozlabs.org Cc: "Masami Hiramatsu (Google)" , Florent Revest , linux-trace-kernel@vger.kernel.org, LKML , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland Subject: Re: [PATCH v14 03/19] function_graph: Pass ftrace_regs to entryfunc Message-ID: <20240915045341.0e246ff3@rorschach.local.home> In-Reply-To: <172615372005.133222.15797801841635819220.stgit@devnote2> References: <172615368656.133222.2336770908714920670.stgit@devnote2> <172615372005.133222.15797801841635819220.stgit@devnote2> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Can I get an Acked-by from the POWERPC maintainers for this patch? Thanks! -- Steve On Fri, 13 Sep 2024 00:08:40 +0900 "Masami Hiramatsu (Google)" wrote: > From: Masami Hiramatsu (Google) > > Pass ftrace_regs to the fgraph_ops::entryfunc(). If ftrace_regs is not > available, it passes a NULL instead. User callback function can access > some registers (including return address) via this ftrace_regs. > > Signed-off-by: Masami Hiramatsu (Google) > --- > Changes in v11: > - Update for the latest for-next branch. > Changes in v8: > - Just pass ftrace_regs to the handler instead of adding a new > entryregfunc. > - Update riscv ftrace_graph_func(). > Changes in v3: > - Update for new multiple fgraph. > --- > arch/arm64/kernel/ftrace.c | 20 +++++++++++- > arch/loongarch/kernel/ftrace_dyn.c | 10 +++++- > arch/powerpc/kernel/trace/ftrace.c | 2 + > arch/powerpc/kernel/trace/ftrace_64_pg.c | 10 ++++-- > arch/riscv/kernel/ftrace.c | 17 ++++++++++ > arch/x86/kernel/ftrace.c | 50 +++++++++++++++++++++--------- > include/linux/ftrace.h | 18 ++++++++--- > kernel/trace/fgraph.c | 23 ++++++++------ > kernel/trace/ftrace.c | 3 +- > kernel/trace/trace.h | 3 +- > kernel/trace/trace_functions_graph.c | 3 +- > kernel/trace/trace_irqsoff.c | 3 +- > kernel/trace/trace_sched_wakeup.c | 3 +- > kernel/trace/trace_selftest.c | 8 +++-- > 14 files changed, 128 insertions(+), 45 deletions(-) > > diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c > index a650f5e11fc5..bc647b725e6a 100644 > --- a/arch/arm64/kernel/ftrace.c > +++ b/arch/arm64/kernel/ftrace.c > @@ -481,7 +481,25 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, > void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > struct ftrace_ops *op, struct ftrace_regs *fregs) > { > - prepare_ftrace_return(ip, &fregs->lr, fregs->fp); > + unsigned long return_hooker = (unsigned long)&return_to_handler; > + unsigned long frame_pointer = fregs->fp; > + unsigned long *parent = &fregs->lr; > + unsigned long old; > + > + if (unlikely(atomic_read(¤t->tracing_graph_pause))) > + return; > + > + /* > + * Note: > + * No protection against faulting at *parent, which may be seen > + * on other archs. It's unlikely on AArch64. > + */ > + old = *parent; > + > + if (!function_graph_enter_regs(old, ip, frame_pointer, > + (void *)frame_pointer, fregs)) { > + *parent = return_hooker; > + } > } > #else > /* > diff --git a/arch/loongarch/kernel/ftrace_dyn.c b/arch/loongarch/kernel/ftrace_dyn.c > index bff058317062..966e0f7f7aca 100644 > --- a/arch/loongarch/kernel/ftrace_dyn.c > +++ b/arch/loongarch/kernel/ftrace_dyn.c > @@ -243,8 +243,16 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > { > struct pt_regs *regs = &fregs->regs; > unsigned long *parent = (unsigned long *)®s->regs[1]; > + unsigned long return_hooker = (unsigned long)&return_to_handler; > + unsigned long old; > + > + if (unlikely(atomic_read(¤t->tracing_graph_pause))) > + return; > + > + old = *parent; > > - prepare_ftrace_return(ip, (unsigned long *)parent); > + if (!function_graph_enter_regs(old, ip, 0, parent, fregs)) > + *parent = return_hooker; > } > #else > static int ftrace_modify_graph_caller(bool enable) > diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c > index d8d6b4fd9a14..a1a0e0b57662 100644 > --- a/arch/powerpc/kernel/trace/ftrace.c > +++ b/arch/powerpc/kernel/trace/ftrace.c > @@ -434,7 +434,7 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > if (bit < 0) > goto out; > > - if (!function_graph_enter(parent_ip, ip, 0, (unsigned long *)sp)) > + if (!function_graph_enter_regs(parent_ip, ip, 0, (unsigned long *)sp, fregs)) > parent_ip = ppc_function_entry(return_to_handler); > > ftrace_test_recursion_unlock(bit); > diff --git a/arch/powerpc/kernel/trace/ftrace_64_pg.c b/arch/powerpc/kernel/trace/ftrace_64_pg.c > index 12fab1803bcf..4ae9eeb1c8f1 100644 > --- a/arch/powerpc/kernel/trace/ftrace_64_pg.c > +++ b/arch/powerpc/kernel/trace/ftrace_64_pg.c > @@ -800,7 +800,8 @@ int ftrace_disable_ftrace_graph_caller(void) > * in current thread info. Return the address we want to divert to. > */ > static unsigned long > -__prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp) > +__prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp, > + struct ftrace_regs *fregs) > { > unsigned long return_hooker; > int bit; > @@ -817,7 +818,7 @@ __prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp > > return_hooker = ppc_function_entry(return_to_handler); > > - if (!function_graph_enter(parent, ip, 0, (unsigned long *)sp)) > + if (!function_graph_enter_regs(parent, ip, 0, (unsigned long *)sp, fregs)) > parent = return_hooker; > > ftrace_test_recursion_unlock(bit); > @@ -829,13 +830,14 @@ __prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp > void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > struct ftrace_ops *op, struct ftrace_regs *fregs) > { > - fregs->regs.link = __prepare_ftrace_return(parent_ip, ip, fregs->regs.gpr[1]); > + fregs->regs.link = __prepare_ftrace_return(parent_ip, ip, > + fregs->regs.gpr[1], fregs); > } > #else > unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip, > unsigned long sp) > { > - return __prepare_ftrace_return(parent, ip, sp); > + return __prepare_ftrace_return(parent, ip, sp, NULL); > } > #endif > #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ > diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c > index 4b95c574fd04..f5c3b5a752b0 100644 > --- a/arch/riscv/kernel/ftrace.c > +++ b/arch/riscv/kernel/ftrace.c > @@ -214,7 +214,22 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, > void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > struct ftrace_ops *op, struct ftrace_regs *fregs) > { > - prepare_ftrace_return(&fregs->ra, ip, fregs->s0); > + unsigned long return_hooker = (unsigned long)&return_to_handler; > + unsigned long frame_pointer = fregs->s0; > + unsigned long *parent = &fregs->ra; > + unsigned long old; > + > + if (unlikely(atomic_read(¤t->tracing_graph_pause))) > + return; > + > + /* > + * We don't suffer access faults, so no extra fault-recovery assembly > + * is needed here. > + */ > + old = *parent; > + > + if (!function_graph_enter_regs(old, ip, frame_pointer, parent, fregs)) > + *parent = return_hooker; > } > #else /* CONFIG_DYNAMIC_FTRACE_WITH_ARGS */ > extern void ftrace_graph_call(void); > diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c > index 8da0e66ca22d..decf4c11dcf3 100644 > --- a/arch/x86/kernel/ftrace.c > +++ b/arch/x86/kernel/ftrace.c > @@ -605,16 +605,8 @@ int ftrace_disable_ftrace_graph_caller(void) > } > #endif /* CONFIG_DYNAMIC_FTRACE && !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ > > -/* > - * Hook the return address and push it in the stack of return addrs > - * in current thread info. > - */ > -void prepare_ftrace_return(unsigned long ip, unsigned long *parent, > - unsigned long frame_pointer) > +static inline bool skip_ftrace_return(void) > { > - unsigned long return_hooker = (unsigned long)&return_to_handler; > - int bit; > - > /* > * When resuming from suspend-to-ram, this function can be indirectly > * called from early CPU startup code while the CPU is in real mode, > @@ -624,13 +616,28 @@ void prepare_ftrace_return(unsigned long ip, unsigned long *parent, > * This check isn't as accurate as virt_addr_valid(), but it should be > * good enough for this purpose, and it's fast. > */ > - if (unlikely((long)__builtin_frame_address(0) >= 0)) > - return; > + if ((long)__builtin_frame_address(0) >= 0) > + return true; > > - if (unlikely(ftrace_graph_is_dead())) > - return; > + if (ftrace_graph_is_dead()) > + return true; > + > + if (atomic_read(¤t->tracing_graph_pause)) > + return true; > + return false; > +} > + > +/* > + * Hook the return address and push it in the stack of return addrs > + * in current thread info. > + */ > +void prepare_ftrace_return(unsigned long ip, unsigned long *parent, > + unsigned long frame_pointer) > +{ > + unsigned long return_hooker = (unsigned long)&return_to_handler; > + int bit; > > - if (unlikely(atomic_read(¤t->tracing_graph_pause))) > + if (unlikely(skip_ftrace_return())) > return; > > bit = ftrace_test_recursion_trylock(ip, *parent); > @@ -649,8 +656,21 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > { > struct pt_regs *regs = &fregs->regs; > unsigned long *stack = (unsigned long *)kernel_stack_pointer(regs); > + unsigned long return_hooker = (unsigned long)&return_to_handler; > + unsigned long *parent = (unsigned long *)stack; > + int bit; > > - prepare_ftrace_return(ip, (unsigned long *)stack, 0); > + if (unlikely(skip_ftrace_return())) > + return; > + > + bit = ftrace_test_recursion_trylock(ip, *parent); > + if (bit < 0) > + return; > + > + if (!function_graph_enter_regs(*parent, ip, 0, parent, fregs)) > + *parent = return_hooker; > + > + ftrace_test_recursion_unlock(bit); > } > #endif > > diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h > index f84fb9635fb0..1fe49a28de2d 100644 > --- a/include/linux/ftrace.h > +++ b/include/linux/ftrace.h > @@ -1063,9 +1063,12 @@ struct fgraph_ops; > typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *, > struct fgraph_ops *); /* return */ > typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *, > - struct fgraph_ops *); /* entry */ > + struct fgraph_ops *, > + struct ftrace_regs *); /* entry */ > > -extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, struct fgraph_ops *gops); > +extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, > + struct fgraph_ops *gops, > + struct ftrace_regs *fregs); > bool ftrace_pids_enabled(struct ftrace_ops *ops); > > #ifdef CONFIG_FUNCTION_GRAPH_TRACER > @@ -1108,8 +1111,15 @@ struct ftrace_ret_stack { > extern void return_to_handler(void); > > extern int > -function_graph_enter(unsigned long ret, unsigned long func, > - unsigned long frame_pointer, unsigned long *retp); > +function_graph_enter_regs(unsigned long ret, unsigned long func, > + unsigned long frame_pointer, unsigned long *retp, > + struct ftrace_regs *fregs); > + > +static inline int function_graph_enter(unsigned long ret, unsigned long func, > + unsigned long fp, unsigned long *retp) > +{ > + return function_graph_enter_regs(ret, func, fp, retp, NULL); > +} > > struct ftrace_ret_stack * > ftrace_graph_get_ret_stack(struct task_struct *task, int skip); > diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c > index d7d4fb403f6f..0322c5723748 100644 > --- a/kernel/trace/fgraph.c > +++ b/kernel/trace/fgraph.c > @@ -290,7 +290,8 @@ static inline unsigned long make_data_type_val(int idx, int size, int offset) > } > > /* ftrace_graph_entry set to this to tell some archs to run function graph */ > -static int entry_run(struct ftrace_graph_ent *trace, struct fgraph_ops *ops) > +static int entry_run(struct ftrace_graph_ent *trace, struct fgraph_ops *ops, > + struct ftrace_regs *fregs) > { > return 0; > } > @@ -484,7 +485,7 @@ int __weak ftrace_disable_ftrace_graph_caller(void) > #endif > > int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, > - struct fgraph_ops *gops) > + struct fgraph_ops *gops, struct ftrace_regs *fregs) > { > return 0; > } > @@ -612,8 +613,9 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func, > #endif > > /* If the caller does not use ftrace, call this function. */ > -int function_graph_enter(unsigned long ret, unsigned long func, > - unsigned long frame_pointer, unsigned long *retp) > +int function_graph_enter_regs(unsigned long ret, unsigned long func, > + unsigned long frame_pointer, unsigned long *retp, > + struct ftrace_regs *fregs) > { > struct ftrace_graph_ent trace; > unsigned long bitmap = 0; > @@ -631,7 +633,7 @@ int function_graph_enter(unsigned long ret, unsigned long func, > if (static_branch_likely(&fgraph_do_direct)) { > int save_curr_ret_stack = current->curr_ret_stack; > > - if (static_call(fgraph_func)(&trace, fgraph_direct_gops)) > + if (static_call(fgraph_func)(&trace, fgraph_direct_gops, fregs)) > bitmap |= BIT(fgraph_direct_gops->idx); > else > /* Clear out any saved storage */ > @@ -649,7 +651,7 @@ int function_graph_enter(unsigned long ret, unsigned long func, > > save_curr_ret_stack = current->curr_ret_stack; > if (ftrace_ops_test(&gops->ops, func, NULL) && > - gops->entryfunc(&trace, gops)) > + gops->entryfunc(&trace, gops, fregs)) > bitmap |= BIT(i); > else > /* Clear out any saved storage */ > @@ -925,7 +927,7 @@ unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx, > > static struct ftrace_ops graph_ops = { > .func = ftrace_graph_func, > - .flags = FTRACE_OPS_GRAPH_STUB, > + .flags = FTRACE_OPS_GRAPH_STUB | FTRACE_OPS_FL_SAVE_ARGS, > #ifdef FTRACE_GRAPH_TRAMP_ADDR > .trampoline = FTRACE_GRAPH_TRAMP_ADDR, > /* trampoline_size is only needed for dynamically allocated tramps */ > @@ -935,7 +937,8 @@ static struct ftrace_ops graph_ops = { > void fgraph_init_ops(struct ftrace_ops *dst_ops, > struct ftrace_ops *src_ops) > { > - dst_ops->flags = FTRACE_OPS_FL_PID | FTRACE_OPS_GRAPH_STUB; > + dst_ops->flags = FTRACE_OPS_FL_PID | FTRACE_OPS_GRAPH_STUB | > + FTRACE_OPS_FL_SAVE_ARGS; > > #ifdef CONFIG_DYNAMIC_FTRACE > if (src_ops) { > @@ -1119,7 +1122,7 @@ void ftrace_graph_exit_task(struct task_struct *t) > > #ifdef CONFIG_DYNAMIC_FTRACE > static int fgraph_pid_func(struct ftrace_graph_ent *trace, > - struct fgraph_ops *gops) > + struct fgraph_ops *gops, struct ftrace_regs *fregs) > { > struct trace_array *tr = gops->ops.private; > int pid; > @@ -1133,7 +1136,7 @@ static int fgraph_pid_func(struct ftrace_graph_ent *trace, > return 0; > } > > - return gops->saved_func(trace, gops); > + return gops->saved_func(trace, gops, fregs); > } > > void fgraph_update_pid_func(void) > diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c > index 4c28dd177ca6..775040a9f541 100644 > --- a/kernel/trace/ftrace.c > +++ b/kernel/trace/ftrace.c > @@ -821,7 +821,8 @@ void ftrace_graph_graph_time_control(bool enable) > } > > static int profile_graph_entry(struct ftrace_graph_ent *trace, > - struct fgraph_ops *gops) > + struct fgraph_ops *gops, > + struct ftrace_regs *fregs) > { > struct ftrace_ret_stack *ret_stack; > > diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h > index bd3e3069300e..28d8ad5e31e6 100644 > --- a/kernel/trace/trace.h > +++ b/kernel/trace/trace.h > @@ -683,7 +683,8 @@ void trace_default_header(struct seq_file *m); > void print_trace_header(struct seq_file *m, struct trace_iterator *iter); > > void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops); > -int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops); > +int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops, > + struct ftrace_regs *fregs); > > void tracing_start_cmdline_record(void); > void tracing_stop_cmdline_record(void); > diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c > index 13d0387ac6a6..b9785fc919c9 100644 > --- a/kernel/trace/trace_functions_graph.c > +++ b/kernel/trace/trace_functions_graph.c > @@ -128,7 +128,8 @@ static inline int ftrace_graph_ignore_irqs(void) > } > > int trace_graph_entry(struct ftrace_graph_ent *trace, > - struct fgraph_ops *gops) > + struct fgraph_ops *gops, > + struct ftrace_regs *fregs) > { > unsigned long *task_var = fgraph_get_task_var(gops); > struct trace_array *tr = gops->private; > diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c > index fce064e20570..ad739d76fc86 100644 > --- a/kernel/trace/trace_irqsoff.c > +++ b/kernel/trace/trace_irqsoff.c > @@ -176,7 +176,8 @@ static int irqsoff_display_graph(struct trace_array *tr, int set) > } > > static int irqsoff_graph_entry(struct ftrace_graph_ent *trace, > - struct fgraph_ops *gops) > + struct fgraph_ops *gops, > + struct ftrace_regs *fregs) > { > struct trace_array *tr = irqsoff_trace; > struct trace_array_cpu *data; > diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c > index 130ca7e7787e..23360a2700de 100644 > --- a/kernel/trace/trace_sched_wakeup.c > +++ b/kernel/trace/trace_sched_wakeup.c > @@ -113,7 +113,8 @@ static int wakeup_display_graph(struct trace_array *tr, int set) > } > > static int wakeup_graph_entry(struct ftrace_graph_ent *trace, > - struct fgraph_ops *gops) > + struct fgraph_ops *gops, > + struct ftrace_regs *fregs) > { > struct trace_array *tr = wakeup_trace; > struct trace_array_cpu *data; > diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c > index c4ad7cd7e778..89067f02094a 100644 > --- a/kernel/trace/trace_selftest.c > +++ b/kernel/trace/trace_selftest.c > @@ -773,7 +773,8 @@ struct fgraph_fixture { > }; > > static __init int store_entry(struct ftrace_graph_ent *trace, > - struct fgraph_ops *gops) > + struct fgraph_ops *gops, > + struct ftrace_regs *fregs) > { > struct fgraph_fixture *fixture = container_of(gops, struct fgraph_fixture, gops); > const char *type = fixture->store_type_name; > @@ -1024,7 +1025,8 @@ static unsigned int graph_hang_thresh; > > /* Wrap the real function entry probe to avoid possible hanging */ > static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace, > - struct fgraph_ops *gops) > + struct fgraph_ops *gops, > + struct ftrace_regs *fregs) > { > /* This is harmlessly racy, we want to approximately detect a hang */ > if (unlikely(++graph_hang_thresh > GRAPH_MAX_FUNC_TEST)) { > @@ -1038,7 +1040,7 @@ static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace, > return 0; > } > > - return trace_graph_entry(trace, gops); > + return trace_graph_entry(trace, gops, fregs); > } > > static struct fgraph_ops fgraph_ops __initdata = {