uprobes: Add support to optimize usdt probes on x86_64

[RFC perf/core 04/11] uprobes: Add data argument to uprobe_write_opcode function

Posted by Jiri Olsa 2 weeks, 4 days ago

Adding data argument to uprobe_write_opcode function and passing
it to newly added arch overloaded functions:

  arch_uprobe_verify_opcode
  arch_uprobe_is_register

This way each architecture can provide custmized verification.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 include/linux/uprobes.h |  6 +++++-
 kernel/events/uprobes.c | 25 +++++++++++++++++++------
 2 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
index 7d23a4fee6f4..be306028ed59 100644
--- a/include/linux/uprobes.h
+++ b/include/linux/uprobes.h
@@ -182,7 +182,7 @@ extern bool is_trap_insn(uprobe_opcode_t *insn);
 extern unsigned long uprobe_get_swbp_addr(struct pt_regs *regs);
 extern unsigned long uprobe_get_trap_addr(struct pt_regs *regs);
 extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
-			       unsigned long vaddr, uprobe_opcode_t *insn, int len);
+			       unsigned long vaddr, uprobe_opcode_t *insn, int len, void *data);
 extern struct uprobe *uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc);
 extern int uprobe_apply(struct uprobe *uprobe, struct uprobe_consumer *uc, bool);
 extern void uprobe_unregister_nosync(struct uprobe *uprobe, struct uprobe_consumer *uc);
@@ -215,6 +215,10 @@ extern void uprobe_handle_trampoline(struct pt_regs *regs);
 extern void *arch_uretprobe_trampoline(unsigned long *psize);
 extern unsigned long uprobe_get_trampoline_vaddr(void);
 extern void uprobe_copy_from_page(struct page *page, unsigned long vaddr, void *dst, int len);
+extern int uprobe_verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode);
+extern int arch_uprobe_verify_opcode(struct page *page, unsigned long vaddr,
+				     uprobe_opcode_t *new_opcode, void *data);
+extern bool arch_uprobe_is_register(uprobe_opcode_t *insn, int len, void *data);
 #else /* !CONFIG_UPROBES */
 struct uprobes_state {
 };
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 3e275717789b..944d9df1f081 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -264,7 +264,13 @@ static void copy_to_page(struct page *page, unsigned long vaddr, const void *src
 	kunmap_atomic(kaddr);
 }
 
-static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode)
+__weak bool arch_uprobe_is_register(uprobe_opcode_t *insn, int len, void *data)
+{
+	return is_swbp_insn(insn);
+}
+
+int uprobe_verify_opcode(struct page *page, unsigned long vaddr,
+			 uprobe_opcode_t *new_opcode)
 {
 	uprobe_opcode_t old_opcode;
 	bool is_swbp;
@@ -292,6 +298,12 @@ static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t
 	return 1;
 }
 
+__weak int arch_uprobe_verify_opcode(struct page *page, unsigned long vaddr,
+				     uprobe_opcode_t *new_opcode, void *data)
+{
+	return uprobe_verify_opcode(page, vaddr, new_opcode);
+}
+
 static struct delayed_uprobe *
 delayed_uprobe_check(struct uprobe *uprobe, struct mm_struct *mm)
 {
@@ -471,7 +483,8 @@ static int update_ref_ctr(struct uprobe *uprobe, struct mm_struct *mm,
  * Return 0 (success) or a negative errno.
  */
 int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
-			unsigned long vaddr, uprobe_opcode_t *insn, int len)
+			unsigned long vaddr, uprobe_opcode_t *insn, int len,
+			void *data)
 {
 	struct uprobe *uprobe;
 	struct page *old_page, *new_page;
@@ -480,7 +493,7 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
 	bool orig_page_huge = false;
 	unsigned int gup_flags = FOLL_FORCE;
 
-	is_register = is_swbp_insn(insn);
+	is_register = arch_uprobe_is_register(insn, len, data);
 	uprobe = container_of(auprobe, struct uprobe, arch);
 
 retry:
@@ -491,7 +504,7 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
 	if (IS_ERR(old_page))
 		return PTR_ERR(old_page);
 
-	ret = verify_opcode(old_page, vaddr, insn);
+	ret = arch_uprobe_verify_opcode(old_page, vaddr, insn, data);
 	if (ret <= 0)
 		goto put_old;
 
@@ -584,7 +597,7 @@ int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned
 {
 	uprobe_opcode_t insn = UPROBE_SWBP_INSN;
 
-	return uprobe_write_opcode(auprobe, mm, vaddr, &insn, UPROBE_SWBP_INSN_SIZE);
+	return uprobe_write_opcode(auprobe, mm, vaddr, &insn, UPROBE_SWBP_INSN_SIZE, NULL);
 }
 
 /**
@@ -600,7 +613,7 @@ int __weak
 set_orig_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr)
 {
 	return uprobe_write_opcode(auprobe, mm, vaddr,
-			(uprobe_opcode_t *)&auprobe->insn, UPROBE_SWBP_INSN_SIZE);
+			(uprobe_opcode_t *)&auprobe->insn, UPROBE_SWBP_INSN_SIZE, NULL);
 }
 
 /* uprobe should have guaranteed positive refcount */
-- 
2.47.0

Re: [RFC perf/core 04/11] uprobes: Add data argument to uprobe_write_opcode function

Posted by Andrii Nakryiko 1 week, 2 days ago

On Tue, Nov 5, 2024 at 5:34 AM Jiri Olsa <jolsa@kernel.org> wrote:
>
> Adding data argument to uprobe_write_opcode function and passing
> it to newly added arch overloaded functions:
>
>   arch_uprobe_verify_opcode
>   arch_uprobe_is_register
>
> This way each architecture can provide custmized verification.
>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---
>  include/linux/uprobes.h |  6 +++++-
>  kernel/events/uprobes.c | 25 +++++++++++++++++++------
>  2 files changed, 24 insertions(+), 7 deletions(-)
>
> diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
> index 7d23a4fee6f4..be306028ed59 100644
> --- a/include/linux/uprobes.h
> +++ b/include/linux/uprobes.h
> @@ -182,7 +182,7 @@ extern bool is_trap_insn(uprobe_opcode_t *insn);
>  extern unsigned long uprobe_get_swbp_addr(struct pt_regs *regs);
>  extern unsigned long uprobe_get_trap_addr(struct pt_regs *regs);
>  extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
> -                              unsigned long vaddr, uprobe_opcode_t *insn, int len);
> +                              unsigned long vaddr, uprobe_opcode_t *insn, int len, void *data);
>  extern struct uprobe *uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc);
>  extern int uprobe_apply(struct uprobe *uprobe, struct uprobe_consumer *uc, bool);
>  extern void uprobe_unregister_nosync(struct uprobe *uprobe, struct uprobe_consumer *uc);
> @@ -215,6 +215,10 @@ extern void uprobe_handle_trampoline(struct pt_regs *regs);
>  extern void *arch_uretprobe_trampoline(unsigned long *psize);
>  extern unsigned long uprobe_get_trampoline_vaddr(void);
>  extern void uprobe_copy_from_page(struct page *page, unsigned long vaddr, void *dst, int len);
> +extern int uprobe_verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode);
> +extern int arch_uprobe_verify_opcode(struct page *page, unsigned long vaddr,
> +                                    uprobe_opcode_t *new_opcode, void *data);
> +extern bool arch_uprobe_is_register(uprobe_opcode_t *insn, int len, void *data);
>  #else /* !CONFIG_UPROBES */
>  struct uprobes_state {
>  };
> diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
> index 3e275717789b..944d9df1f081 100644
> --- a/kernel/events/uprobes.c
> +++ b/kernel/events/uprobes.c
> @@ -264,7 +264,13 @@ static void copy_to_page(struct page *page, unsigned long vaddr, const void *src
>         kunmap_atomic(kaddr);
>  }
>
> -static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode)
> +__weak bool arch_uprobe_is_register(uprobe_opcode_t *insn, int len, void *data)
> +{
> +       return is_swbp_insn(insn);
> +}
> +
> +int uprobe_verify_opcode(struct page *page, unsigned long vaddr,
> +                        uprobe_opcode_t *new_opcode)
>  {
>         uprobe_opcode_t old_opcode;
>         bool is_swbp;
> @@ -292,6 +298,12 @@ static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t
>         return 1;
>  }
>
> +__weak int arch_uprobe_verify_opcode(struct page *page, unsigned long vaddr,
> +                                    uprobe_opcode_t *new_opcode, void *data)

why wrapping lines? even original longer code was single line


> +{
> +       return uprobe_verify_opcode(page, vaddr, new_opcode);
> +}
> +
>  static struct delayed_uprobe *
>  delayed_uprobe_check(struct uprobe *uprobe, struct mm_struct *mm)
>  {
> @@ -471,7 +483,8 @@ static int update_ref_ctr(struct uprobe *uprobe, struct mm_struct *mm,
>   * Return 0 (success) or a negative errno.
>   */
>  int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
> -                       unsigned long vaddr, uprobe_opcode_t *insn, int len)
> +                       unsigned long vaddr, uprobe_opcode_t *insn, int len,
> +                       void *data)
>  {
>         struct uprobe *uprobe;
>         struct page *old_page, *new_page;
> @@ -480,7 +493,7 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
>         bool orig_page_huge = false;
>         unsigned int gup_flags = FOLL_FORCE;
>
> -       is_register = is_swbp_insn(insn);
> +       is_register = arch_uprobe_is_register(insn, len, data);
>         uprobe = container_of(auprobe, struct uprobe, arch);
>
>  retry:
> @@ -491,7 +504,7 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
>         if (IS_ERR(old_page))
>                 return PTR_ERR(old_page);
>
> -       ret = verify_opcode(old_page, vaddr, insn);
> +       ret = arch_uprobe_verify_opcode(old_page, vaddr, insn, data);
>         if (ret <= 0)
>                 goto put_old;
>
> @@ -584,7 +597,7 @@ int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned
>  {
>         uprobe_opcode_t insn = UPROBE_SWBP_INSN;
>
> -       return uprobe_write_opcode(auprobe, mm, vaddr, &insn, UPROBE_SWBP_INSN_SIZE);
> +       return uprobe_write_opcode(auprobe, mm, vaddr, &insn, UPROBE_SWBP_INSN_SIZE, NULL);
>  }
>
>  /**
> @@ -600,7 +613,7 @@ int __weak
>  set_orig_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr)
>  {
>         return uprobe_write_opcode(auprobe, mm, vaddr,
> -                       (uprobe_opcode_t *)&auprobe->insn, UPROBE_SWBP_INSN_SIZE);
> +                       (uprobe_opcode_t *)&auprobe->insn, UPROBE_SWBP_INSN_SIZE, NULL);
>  }
>
>  /* uprobe should have guaranteed positive refcount */
> --
> 2.47.0
>

Re: [RFC perf/core 04/11] uprobes: Add data argument to uprobe_write_opcode function

Posted by Jiri Olsa 1 week ago

On Thu, Nov 14, 2024 at 03:41:08PM -0800, Andrii Nakryiko wrote:
> On Tue, Nov 5, 2024 at 5:34 AM Jiri Olsa <jolsa@kernel.org> wrote:
> >
> > Adding data argument to uprobe_write_opcode function and passing
> > it to newly added arch overloaded functions:
> >
> >   arch_uprobe_verify_opcode
> >   arch_uprobe_is_register
> >
> > This way each architecture can provide custmized verification.
> >
> > Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> > ---
> >  include/linux/uprobes.h |  6 +++++-
> >  kernel/events/uprobes.c | 25 +++++++++++++++++++------
> >  2 files changed, 24 insertions(+), 7 deletions(-)
> >
> > diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
> > index 7d23a4fee6f4..be306028ed59 100644
> > --- a/include/linux/uprobes.h
> > +++ b/include/linux/uprobes.h
> > @@ -182,7 +182,7 @@ extern bool is_trap_insn(uprobe_opcode_t *insn);
> >  extern unsigned long uprobe_get_swbp_addr(struct pt_regs *regs);
> >  extern unsigned long uprobe_get_trap_addr(struct pt_regs *regs);
> >  extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
> > -                              unsigned long vaddr, uprobe_opcode_t *insn, int len);
> > +                              unsigned long vaddr, uprobe_opcode_t *insn, int len, void *data);
> >  extern struct uprobe *uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc);
> >  extern int uprobe_apply(struct uprobe *uprobe, struct uprobe_consumer *uc, bool);
> >  extern void uprobe_unregister_nosync(struct uprobe *uprobe, struct uprobe_consumer *uc);
> > @@ -215,6 +215,10 @@ extern void uprobe_handle_trampoline(struct pt_regs *regs);
> >  extern void *arch_uretprobe_trampoline(unsigned long *psize);
> >  extern unsigned long uprobe_get_trampoline_vaddr(void);
> >  extern void uprobe_copy_from_page(struct page *page, unsigned long vaddr, void *dst, int len);
> > +extern int uprobe_verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode);
> > +extern int arch_uprobe_verify_opcode(struct page *page, unsigned long vaddr,
> > +                                    uprobe_opcode_t *new_opcode, void *data);
> > +extern bool arch_uprobe_is_register(uprobe_opcode_t *insn, int len, void *data);
> >  #else /* !CONFIG_UPROBES */
> >  struct uprobes_state {
> >  };
> > diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
> > index 3e275717789b..944d9df1f081 100644
> > --- a/kernel/events/uprobes.c
> > +++ b/kernel/events/uprobes.c
> > @@ -264,7 +264,13 @@ static void copy_to_page(struct page *page, unsigned long vaddr, const void *src
> >         kunmap_atomic(kaddr);
> >  }
> >
> > -static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode)
> > +__weak bool arch_uprobe_is_register(uprobe_opcode_t *insn, int len, void *data)
> > +{
> > +       return is_swbp_insn(insn);
> > +}
> > +
> > +int uprobe_verify_opcode(struct page *page, unsigned long vaddr,
> > +                        uprobe_opcode_t *new_opcode)
> >  {
> >         uprobe_opcode_t old_opcode;
> >         bool is_swbp;
> > @@ -292,6 +298,12 @@ static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t
> >         return 1;
> >  }
> >
> > +__weak int arch_uprobe_verify_opcode(struct page *page, unsigned long vaddr,
> > +                                    uprobe_opcode_t *new_opcode, void *data)
> 
> why wrapping lines? even original longer code was single line

hm, adding 'uprobe_opcode_t *new_opcode' would make the line over 100 chars,
but right, surrouding code is not strict ;-) ok

jirka

> 
> 
> > +{
> > +       return uprobe_verify_opcode(page, vaddr, new_opcode);
> > +}
> > +
> >  static struct delayed_uprobe *
> >  delayed_uprobe_check(struct uprobe *uprobe, struct mm_struct *mm)
> >  {
> > @@ -471,7 +483,8 @@ static int update_ref_ctr(struct uprobe *uprobe, struct mm_struct *mm,
> >   * Return 0 (success) or a negative errno.
> >   */
> >  int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
> > -                       unsigned long vaddr, uprobe_opcode_t *insn, int len)
> > +                       unsigned long vaddr, uprobe_opcode_t *insn, int len,
> > +                       void *data)
> >  {
> >         struct uprobe *uprobe;
> >         struct page *old_page, *new_page;
> > @@ -480,7 +493,7 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
> >         bool orig_page_huge = false;
> >         unsigned int gup_flags = FOLL_FORCE;
> >
> > -       is_register = is_swbp_insn(insn);
> > +       is_register = arch_uprobe_is_register(insn, len, data);
> >         uprobe = container_of(auprobe, struct uprobe, arch);
> >
> >  retry:
> > @@ -491,7 +504,7 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
> >         if (IS_ERR(old_page))
> >                 return PTR_ERR(old_page);
> >
> > -       ret = verify_opcode(old_page, vaddr, insn);
> > +       ret = arch_uprobe_verify_opcode(old_page, vaddr, insn, data);
> >         if (ret <= 0)
> >                 goto put_old;
> >
> > @@ -584,7 +597,7 @@ int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned
> >  {
> >         uprobe_opcode_t insn = UPROBE_SWBP_INSN;
> >
> > -       return uprobe_write_opcode(auprobe, mm, vaddr, &insn, UPROBE_SWBP_INSN_SIZE);
> > +       return uprobe_write_opcode(auprobe, mm, vaddr, &insn, UPROBE_SWBP_INSN_SIZE, NULL);
> >  }
> >
> >  /**
> > @@ -600,7 +613,7 @@ int __weak
> >  set_orig_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr)
> >  {
> >         return uprobe_write_opcode(auprobe, mm, vaddr,
> > -                       (uprobe_opcode_t *)&auprobe->insn, UPROBE_SWBP_INSN_SIZE);
> > +                       (uprobe_opcode_t *)&auprobe->insn, UPROBE_SWBP_INSN_SIZE, NULL);
> >  }
> >
> >  /* uprobe should have guaranteed positive refcount */
> > --
> > 2.47.0
> >