| Message ID | 172615377576.133222.5911358383330497277.stgit@devnote2 (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph | expand |
Can I get an Acked-by from the AARCH64 maintainers for this patch? Thanks! -- Steve On Fri, 13 Sep 2024 00:09:35 +0900 "Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote: > From: Masami Hiramatsu (Google) <mhiramat@kernel.org> > > Add ftrace_partial_regs() which converts the ftrace_regs to pt_regs. > This is for the eBPF which needs this to keep the same pt_regs interface > to access registers. > Thus when replacing the pt_regs with ftrace_regs in fprobes (which is > used by kprobe_multi eBPF event), this will be used. > > If the architecture defines its own ftrace_regs, this copies partial > registers to pt_regs and returns it. If not, ftrace_regs is the same as > pt_regs and ftrace_partial_regs() will return ftrace_regs::regs. > > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> > Acked-by: Florent Revest <revest@chromium.org> > --- > Changes in v14: > - Add riscv change. > Changes in v8: > - Add the reason why this required in changelog. > Changes from previous series: NOTHING, just forward ported. > --- > arch/arm64/include/asm/ftrace.h | 11 +++++++++++ > arch/riscv/include/asm/ftrace.h | 12 ++++++++++++ > include/linux/ftrace.h | 17 +++++++++++++++++ > 3 files changed, 40 insertions(+) > > diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h > index dffaab3dd1f1..5cd587afab6d 100644 > --- a/arch/arm64/include/asm/ftrace.h > +++ b/arch/arm64/include/asm/ftrace.h > @@ -132,6 +132,17 @@ ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs) > return fregs->fp; > } > > +static __always_inline struct pt_regs * > +ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) > +{ > + memcpy(regs->regs, fregs->regs, sizeof(u64) * 9); > + regs->sp = fregs->sp; > + regs->pc = fregs->pc; > + regs->regs[29] = fregs->fp; > + regs->regs[30] = fregs->lr; > + return regs; > +} > + > int ftrace_regs_query_register_offset(const char *name); > > int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); > diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h > index e9f364ce9fe8..897779dec402 100644 > --- a/arch/riscv/include/asm/ftrace.h > +++ b/arch/riscv/include/asm/ftrace.h > @@ -193,6 +193,18 @@ static __always_inline void ftrace_override_function_with_return(struct ftrace_r > fregs->epc = fregs->ra; > } > > +static __always_inline struct pt_regs * > +ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) > +{ > + memcpy(®s->a0, fregs->args, sizeof(u64) * 8); > + regs->epc = fregs->epc; > + regs->ra = fregs->ra; > + regs->sp = fregs->sp; > + regs->s0 = fregs->s0; > + regs->t1 = fregs->t1; > + return regs; > +} > + > int ftrace_regs_query_register_offset(const char *name); > > void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, > diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h > index a1b2ef492c7f..bd9a26bdf660 100644 > --- a/include/linux/ftrace.h > +++ b/include/linux/ftrace.h > @@ -176,6 +176,23 @@ static __always_inline struct pt_regs *ftrace_get_regs(struct ftrace_regs *fregs > return arch_ftrace_get_regs(fregs); > } > > +#if !defined(CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS) || \ > + defined(CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST) > + > +static __always_inline struct pt_regs * > +ftrace_partial_regs(struct ftrace_regs *fregs, struct pt_regs *regs) > +{ > + /* > + * If CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST=y, ftrace_regs memory > + * layout is the same as pt_regs. So always returns that address. > + * Since arch_ftrace_get_regs() will check some members and may return > + * NULL, we can not use it. > + */ > + return &fregs->regs; > +} > + > +#endif /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS || CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST */ > + > /* > * When true, the ftrace_regs_{get,set}_*() functions may be used on fregs. > * Note: this can be true even when ftrace_get_regs() cannot provide a pt_regs.
On Sun, Sep 15, 2024 at 05:22:04AM -0400, Steven Rostedt wrote: > On Fri, 13 Sep 2024 00:09:35 +0900 > "Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote: > > > From: Masami Hiramatsu (Google) <mhiramat@kernel.org> > > > > Add ftrace_partial_regs() which converts the ftrace_regs to pt_regs. > > This is for the eBPF which needs this to keep the same pt_regs interface > > to access registers. > > Thus when replacing the pt_regs with ftrace_regs in fprobes (which is > > used by kprobe_multi eBPF event), this will be used. > > > > If the architecture defines its own ftrace_regs, this copies partial > > registers to pt_regs and returns it. If not, ftrace_regs is the same as > > pt_regs and ftrace_partial_regs() will return ftrace_regs::regs. > > > > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> > > Acked-by: Florent Revest <revest@chromium.org> > > --- > > Changes in v14: > > - Add riscv change. > > Changes in v8: > > - Add the reason why this required in changelog. > > Changes from previous series: NOTHING, just forward ported. > > --- > > arch/arm64/include/asm/ftrace.h | 11 +++++++++++ > > arch/riscv/include/asm/ftrace.h | 12 ++++++++++++ > > include/linux/ftrace.h | 17 +++++++++++++++++ > > 3 files changed, 40 insertions(+) > > > > diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h > > index dffaab3dd1f1..5cd587afab6d 100644 > > --- a/arch/arm64/include/asm/ftrace.h > > +++ b/arch/arm64/include/asm/ftrace.h > > @@ -132,6 +132,17 @@ ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs) > > return fregs->fp; > > } > > > > +static __always_inline struct pt_regs * > > +ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) > > +{ > > + memcpy(regs->regs, fregs->regs, sizeof(u64) * 9); > > + regs->sp = fregs->sp; > > + regs->pc = fregs->pc; > > + regs->regs[29] = fregs->fp; > > + regs->regs[30] = fregs->lr; > > + return regs; > > +} Ah, I guess this is where we pick up the lr that was set in patch 5. Acked-by: Will Deacon <will@kernel.org> Will
On Tue, 17 Sep 2024 11:14:54 +0100 Will Deacon <will@kernel.org> wrote: > On Sun, Sep 15, 2024 at 05:22:04AM -0400, Steven Rostedt wrote: > > On Fri, 13 Sep 2024 00:09:35 +0900 > > "Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote: > > > > > From: Masami Hiramatsu (Google) <mhiramat@kernel.org> > > > > > > Add ftrace_partial_regs() which converts the ftrace_regs to pt_regs. > > > This is for the eBPF which needs this to keep the same pt_regs interface > > > to access registers. > > > Thus when replacing the pt_regs with ftrace_regs in fprobes (which is > > > used by kprobe_multi eBPF event), this will be used. > > > > > > If the architecture defines its own ftrace_regs, this copies partial > > > registers to pt_regs and returns it. If not, ftrace_regs is the same as > > > pt_regs and ftrace_partial_regs() will return ftrace_regs::regs. > > > > > > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> > > > Acked-by: Florent Revest <revest@chromium.org> > > > --- > > > Changes in v14: > > > - Add riscv change. > > > Changes in v8: > > > - Add the reason why this required in changelog. > > > Changes from previous series: NOTHING, just forward ported. > > > --- > > > arch/arm64/include/asm/ftrace.h | 11 +++++++++++ > > > arch/riscv/include/asm/ftrace.h | 12 ++++++++++++ > > > include/linux/ftrace.h | 17 +++++++++++++++++ > > > 3 files changed, 40 insertions(+) > > > > > > diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h > > > index dffaab3dd1f1..5cd587afab6d 100644 > > > --- a/arch/arm64/include/asm/ftrace.h > > > +++ b/arch/arm64/include/asm/ftrace.h > > > @@ -132,6 +132,17 @@ ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs) > > > return fregs->fp; > > > } > > > > > > +static __always_inline struct pt_regs * > > > +ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) > > > +{ > > > + memcpy(regs->regs, fregs->regs, sizeof(u64) * 9); > > > + regs->sp = fregs->sp; > > > + regs->pc = fregs->pc; > > > + regs->regs[29] = fregs->fp; > > > + regs->regs[30] = fregs->lr; > > > + return regs; > > > +} > > Ah, I guess this is where we pick up the lr that was set in patch 5. Yeah, this one also copies the fregs->pc to regs->pc, mainly for bpf. > > Acked-by: Will Deacon <will@kernel.org> Thank you! > > Will
diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index dffaab3dd1f1..5cd587afab6d 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -132,6 +132,17 @@ ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs) return fregs->fp; } +static __always_inline struct pt_regs * +ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) +{ + memcpy(regs->regs, fregs->regs, sizeof(u64) * 9); + regs->sp = fregs->sp; + regs->pc = fregs->pc; + regs->regs[29] = fregs->fp; + regs->regs[30] = fregs->lr; + return regs; +} + int ftrace_regs_query_register_offset(const char *name); int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h index e9f364ce9fe8..897779dec402 100644 --- a/arch/riscv/include/asm/ftrace.h +++ b/arch/riscv/include/asm/ftrace.h @@ -193,6 +193,18 @@ static __always_inline void ftrace_override_function_with_return(struct ftrace_r fregs->epc = fregs->ra; } +static __always_inline struct pt_regs * +ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) +{ + memcpy(®s->a0, fregs->args, sizeof(u64) * 8); + regs->epc = fregs->epc; + regs->ra = fregs->ra; + regs->sp = fregs->sp; + regs->s0 = fregs->s0; + regs->t1 = fregs->t1; + return regs; +} + int ftrace_regs_query_register_offset(const char *name); void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index a1b2ef492c7f..bd9a26bdf660 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -176,6 +176,23 @@ static __always_inline struct pt_regs *ftrace_get_regs(struct ftrace_regs *fregs return arch_ftrace_get_regs(fregs); } +#if !defined(CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS) || \ + defined(CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST) + +static __always_inline struct pt_regs * +ftrace_partial_regs(struct ftrace_regs *fregs, struct pt_regs *regs) +{ + /* + * If CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST=y, ftrace_regs memory + * layout is the same as pt_regs. So always returns that address. + * Since arch_ftrace_get_regs() will check some members and may return + * NULL, we can not use it. + */ + return &fregs->regs; +} + +#endif /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS || CONFIG_HAVE_PT_REGS_TO_FTRACE_REGS_CAST */ + /* * When true, the ftrace_regs_{get,set}_*() functions may be used on fregs. * Note: this can be true even when ftrace_get_regs() cannot provide a pt_regs.