| Message ID | 172904035199.36809.9900108557809424653.stgit@devnote2 (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Guessing tree name failed - patch did not apply |
| bpf/vmtest-bpf-PR | fail | merge-conflict |
On Wed, Oct 16, 2024 at 09:59:12AM +0900, Masami Hiramatsu (Google) wrote: > From: Masami Hiramatsu (Google) <mhiramat@kernel.org> > > Add ftrace_fill_perf_regs() which should be compatible with the > perf_fetch_caller_regs(). In other words, the pt_regs returned from the > ftrace_fill_perf_regs() must satisfy 'user_mode(regs) == false' and can be > used for stack tracing. > > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> > Cc: Steven Rostedt <rostedt@goodmis.org> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Will Deacon <will@kernel.org> > Cc: Michael Ellerman <mpe@ellerman.id.au> > Cc: Nicholas Piggin <npiggin@gmail.com> > Cc: Christophe Leroy <christophe.leroy@csgroup.eu> > Cc: Naveen N Rao <naveen@kernel.org> > Cc: Madhavan Srinivasan <maddy@linux.ibm.com> > Cc: Heiko Carstens <hca@linux.ibm.com> > Cc: Vasily Gorbik <gor@linux.ibm.com> > Cc: Alexander Gordeev <agordeev@linux.ibm.com> > Cc: Christian Borntraeger <borntraeger@linux.ibm.com> > Cc: Sven Schnelle <svens@linux.ibm.com> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Ingo Molnar <mingo@redhat.com> > Cc: Borislav Petkov <bp@alien8.de> > Cc: Dave Hansen <dave.hansen@linux.intel.com> > Cc: x86@kernel.org > Cc: "H. Peter Anvin" <hpa@zytor.com> > > --- > Changes in v16: > - Fix s390 to clear psw.mask according to Heiko's suggestion. > --- > arch/arm64/include/asm/ftrace.h | 7 +++++++ > arch/powerpc/include/asm/ftrace.h | 7 +++++++ > arch/s390/include/asm/ftrace.h | 6 ++++++ > arch/x86/include/asm/ftrace.h | 7 +++++++ > include/linux/ftrace.h | 31 +++++++++++++++++++++++++++++++ > 5 files changed, 58 insertions(+) > > diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h > index d344c69eb01e..6493a575664f 100644 > --- a/arch/arm64/include/asm/ftrace.h > +++ b/arch/arm64/include/asm/ftrace.h > @@ -146,6 +146,13 @@ ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) > return regs; > } > > +#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ > + (_regs)->pc = arch_ftrace_regs(fregs)->pc; \ > + (_regs)->regs[29] = arch_ftrace_regs(fregs)->fp; \ > + (_regs)->sp = arch_ftrace_regs(fregs)->sp; \ > + (_regs)->pstate = PSR_MODE_EL1h; \ > + } while (0) arm64 bit looks correct to me: Acked-by: Will Deacon <will@kernel.org> Will
On Mon, 21 Oct 2024 18:01:21 +0100 Will Deacon <will@kernel.org> wrote: > On Wed, Oct 16, 2024 at 09:59:12AM +0900, Masami Hiramatsu (Google) wrote: > > From: Masami Hiramatsu (Google) <mhiramat@kernel.org> > > > > Add ftrace_fill_perf_regs() which should be compatible with the > > perf_fetch_caller_regs(). In other words, the pt_regs returned from the > > ftrace_fill_perf_regs() must satisfy 'user_mode(regs) == false' and can be > > used for stack tracing. > > > > Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> > > Cc: Steven Rostedt <rostedt@goodmis.org> > > Cc: Mark Rutland <mark.rutland@arm.com> > > Cc: Catalin Marinas <catalin.marinas@arm.com> > > Cc: Will Deacon <will@kernel.org> > > Cc: Michael Ellerman <mpe@ellerman.id.au> > > Cc: Nicholas Piggin <npiggin@gmail.com> > > Cc: Christophe Leroy <christophe.leroy@csgroup.eu> > > Cc: Naveen N Rao <naveen@kernel.org> > > Cc: Madhavan Srinivasan <maddy@linux.ibm.com> > > Cc: Heiko Carstens <hca@linux.ibm.com> > > Cc: Vasily Gorbik <gor@linux.ibm.com> > > Cc: Alexander Gordeev <agordeev@linux.ibm.com> > > Cc: Christian Borntraeger <borntraeger@linux.ibm.com> > > Cc: Sven Schnelle <svens@linux.ibm.com> > > Cc: Thomas Gleixner <tglx@linutronix.de> > > Cc: Ingo Molnar <mingo@redhat.com> > > Cc: Borislav Petkov <bp@alien8.de> > > Cc: Dave Hansen <dave.hansen@linux.intel.com> > > Cc: x86@kernel.org > > Cc: "H. Peter Anvin" <hpa@zytor.com> > > > > --- > > Changes in v16: > > - Fix s390 to clear psw.mask according to Heiko's suggestion. > > --- > > arch/arm64/include/asm/ftrace.h | 7 +++++++ > > arch/powerpc/include/asm/ftrace.h | 7 +++++++ > > arch/s390/include/asm/ftrace.h | 6 ++++++ > > arch/x86/include/asm/ftrace.h | 7 +++++++ > > include/linux/ftrace.h | 31 +++++++++++++++++++++++++++++++ > > 5 files changed, 58 insertions(+) > > > > diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h > > index d344c69eb01e..6493a575664f 100644 > > --- a/arch/arm64/include/asm/ftrace.h > > +++ b/arch/arm64/include/asm/ftrace.h > > @@ -146,6 +146,13 @@ ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) > > return regs; > > } > > > > +#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ > > + (_regs)->pc = arch_ftrace_regs(fregs)->pc; \ > > + (_regs)->regs[29] = arch_ftrace_regs(fregs)->fp; \ > > + (_regs)->sp = arch_ftrace_regs(fregs)->sp; \ > > + (_regs)->pstate = PSR_MODE_EL1h; \ > > + } while (0) > > arm64 bit looks correct to me: > > 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 d344c69eb01e..6493a575664f 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -146,6 +146,13 @@ ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs *regs) return regs; } +#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ + (_regs)->pc = arch_ftrace_regs(fregs)->pc; \ + (_regs)->regs[29] = arch_ftrace_regs(fregs)->fp; \ + (_regs)->sp = arch_ftrace_regs(fregs)->sp; \ + (_regs)->pstate = PSR_MODE_EL1h; \ + } while (0) + int ftrace_regs_query_register_offset(const char *name); int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h index 0edfb874eb02..407ce6eccc04 100644 --- a/arch/powerpc/include/asm/ftrace.h +++ b/arch/powerpc/include/asm/ftrace.h @@ -40,6 +40,13 @@ static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs * return arch_ftrace_regs(fregs)->regs.msr ? &arch_ftrace_regs(fregs)->regs : NULL; } +#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ + (_regs)->result = 0; \ + (_regs)->nip = arch_ftrace_regs(fregs)->regs.nip; \ + (_regs)->gpr[1] = arch_ftrace_regs(fregs)->regs.gpr[1]; \ + asm volatile("mfmsr %0" : "=r" ((_regs)->msr)); \ + } while (0) + static __always_inline void ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, unsigned long ip) diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h index 5c94c1fc1bc1..5b7cb49c41ee 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -76,6 +76,12 @@ ftrace_regs_get_frame_pointer(struct ftrace_regs *fregs) return ftrace_regs_get_stack_pointer(fregs); } +#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ + (_regs)->psw.mask = 0; \ + (_regs)->psw.addr = arch_ftrace_regs(fregs)->regs.psw.addr; \ + (_regs)->gprs[15] = arch_ftrace_regs(fregs)->regs.gprs[15]; \ + } while (0) + #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS /* * When an ftrace registered caller is tracing a function that is diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h index 2160d11945ce..d88f285258b2 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -45,6 +45,13 @@ arch_ftrace_get_regs(struct ftrace_regs *fregs) return &arch_ftrace_regs(fregs)->regs; } +#define arch_ftrace_fill_perf_regs(fregs, _regs) do { \ + (_regs)->ip = arch_ftrace_regs(fregs)->regs.ip; \ + (_regs)->sp = arch_ftrace_regs(fregs)->regs.sp; \ + (_regs)->cs = __KERNEL_CS; \ + (_regs)->flags = 0; \ + } while (0) + #define ftrace_regs_set_instruction_pointer(fregs, _ip) \ do { arch_ftrace_regs(fregs)->regs.ip = (_ip); } while (0) diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index ad2b46e1d5b0..6d29c640697c 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -207,6 +207,37 @@ ftrace_partial_regs(struct ftrace_regs *fregs, struct pt_regs *regs) #endif /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS || CONFIG_HAVE_FTRACE_REGS_HAVING_PT_REGS */ +#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS + +/* + * Please define arch dependent pt_regs which compatible to the + * perf_arch_fetch_caller_regs() but based on ftrace_regs. + * This requires + * - user_mode(_regs) returns false (always kernel mode). + * - able to use the _regs for stack trace. + */ +#ifndef arch_ftrace_fill_perf_regs +/* As same as perf_arch_fetch_caller_regs(), do nothing by default */ +#define arch_ftrace_fill_perf_regs(fregs, _regs) do {} while (0) +#endif + +static __always_inline struct pt_regs * +ftrace_fill_perf_regs(struct ftrace_regs *fregs, struct pt_regs *regs) +{ + arch_ftrace_fill_perf_regs(fregs, regs); + return regs; +} + +#else /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ + +static __always_inline struct pt_regs * +ftrace_fill_perf_regs(struct ftrace_regs *fregs, struct pt_regs *regs) +{ + return &arch_ftrace_regs(fregs)->regs; +} + +#endif + /* * 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.