| Message ID | 172895581574.107311.17609909207681074574.stgit@devnote2 (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph | expand |
On Tue, Oct 15, 2024 at 10:30:15AM +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> > --- > Changes from previous series: NOTHING, just forward ported. > --- > arch/s390/include/asm/ftrace.h | 5 +++++ ... > diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h > index 5c94c1fc1bc1..f1c0e677a325 100644 > --- a/arch/s390/include/asm/ftrace.h > +++ b/arch/s390/include/asm/ftrace.h > @@ -76,6 +76,11 @@ 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.addr = arch_ftrace_regs(fregs)->regs.psw.addr; \ > + (_regs)->gprs[15] = arch_ftrace_regs(fregs)->regs.gprs[15]; \ > + } while (0) > + This misses the feedback I gave for v15: https://lore.kernel.org/all/20241009100502.8007-E-hca@linux.ibm.com
On Tue, 15 Oct 2024 20:18:02 +0200 Heiko Carstens <hca@linux.ibm.com> wrote: > On Tue, Oct 15, 2024 at 10:30:15AM +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> > > --- > > Changes from previous series: NOTHING, just forward ported. > > --- > > arch/s390/include/asm/ftrace.h | 5 +++++ > > ... > > > diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h > > index 5c94c1fc1bc1..f1c0e677a325 100644 > > --- a/arch/s390/include/asm/ftrace.h > > +++ b/arch/s390/include/asm/ftrace.h > > @@ -76,6 +76,11 @@ 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.addr = arch_ftrace_regs(fregs)->regs.psw.addr; \ > > + (_regs)->gprs[15] = arch_ftrace_regs(fregs)->regs.gprs[15]; \ > > + } while (0) > > + > > This misses the feedback I gave for v15: > https://lore.kernel.org/all/20241009100502.8007-E-hca@linux.ibm.com Oops, sorry. And thanks for your feedback!
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..f1c0e677a325 100644 --- a/arch/s390/include/asm/ftrace.h +++ b/arch/s390/include/asm/ftrace.h @@ -76,6 +76,11 @@ 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.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 d61407c680c2..7e06f8c7937a 100644 --- a/arch/x86/include/asm/ftrace.h +++ b/arch/x86/include/asm/ftrace.h @@ -47,6 +47,13 @@ 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.