* [PATCH v3 0/2] riscv/ftrace: make function graph use ftrace directly
@ 2022-11-18 17:32 Song Shuai
2022-11-18 17:32 ` [PATCH v3 1/2] riscv/ftrace: add ftrace_graph_func Song Shuai
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Song Shuai @ 2022-11-18 17:32 UTC (permalink / raw)
To: guoren, rostedt, mhiramat, mark.rutland, paul.walmsley, palmer, aou
Cc: linux-riscv, linux-kernel, Song Shuai
In RISC-V architecture, when we enable the ftrace_graph tracer on some
functions, the function tracings on other functions will suffer extra
graph tracing work. In essence, graph_ops isn't limited by its func_hash
due to the global ftrace_graph_[regs]_call label. That should be corrected.
What inspires me is the commit 0c0593b45c9b ("x86/ftrace: Make function
graph use ftrace directly") that uses graph_ops::func function to install
return_hooker and makes the function called against its func_hash.
This series of patches makes function graph use ftrace directly for riscv.
If FTRACE_WITH_REGS isn't defined, ftrace_caller keeps ftrace_graph_call
so that it can be replaced with the calling of prepare_ftrace_return by
the enable/disable helper.
As for defining FTRACE_WITH_REGS, ftrace_caller is adjusted to save the
necessary regs against the pt_regs layout, so it can reasonably call the
graph_ops::func function - ftrace_graph_func. And ftrace_graph_[regs]_call
and its enable/disable helper aren't needed.
The tests generated by CONFIG_FTRACE_STARTUP_TEST have passed in the local
qemu-system-riscv64 virt machine. The following is the log during startup.
```
Nov 15 03:07:13 stage4 kernel: Testing tracer function: PASSED
Nov 15 03:07:13 stage4 kernel: Testing dynamic ftrace: PASSED
Nov 15 03:07:13 stage4 kernel: Testing dynamic ftrace ops #1:
Nov 15 03:07:13 stage4 kernel: (1 0 1 0 0)
Nov 15 03:07:13 stage4 kernel: (1 1 2 0 0)
Nov 15 03:07:13 stage4 kernel: (2 1 3 0 365)
Nov 15 03:07:13 stage4 kernel: (2 2 4 0 399)
Nov 15 03:07:13 stage4 kernel: (3 2 4 0 146071)
Nov 15 03:07:13 stage4 kernel: (3 3 5 0 146105) PASSED
Nov 15 03:07:13 stage4 kernel: Testing dynamic ftrace ops #2:
Nov 15 03:07:13 stage4 kernel: (1 0 1 589 0)
Nov 15 03:07:13 stage4 kernel: (1 1 2 635 0)
Nov 15 03:07:13 stage4 kernel: (2 1 3 1 2)
Nov 15 03:07:13 stage4 kernel: (2 2 4 125 126)
Nov 15 03:07:13 stage4 kernel: (3 2 4 146001 146078)
Nov 15 03:07:13 stage4 kernel: (3 3 5 146035 146112) PASSED
Nov 15 03:07:13 stage4 kernel: Testing ftrace recursion: PASSED
Nov 15 03:07:13 stage4 kernel: Testing ftrace recursion safe: PASSED
Nov 15 03:07:13 stage4 kernel: Testing ftrace regs: PASSED
Nov 15 03:07:13 stage4 kernel: Testing tracer nop: PASSED
Nov 15 03:07:13 stage4 kernel: Testing tracer irqsoff: PASSED
Nov 15 03:07:13 stage4 kernel: Testing tracer wakeup:
Nov 15 03:07:13 stage4 kernel: sched: DL replenish lagged too much
Nov 15 03:07:13 stage4 kernel: PASSED
Nov 15 03:07:13 stage4 kernel: Testing tracer wakeup_rt: PASSED
Nov 15 03:07:13 stage4 kernel: Testing tracer wakeup_dl: PASSED
Nov 15 03:07:13 stage4 kernel: Testing tracer function_graph: PASSED
```
Note that the changes of mcount-dyn.S conflicts with this unmerged
commit (riscv: entry: consolidate general regs saving/restoring).
https://lore.kernel.org/linux-riscv/20221103075047.1634923-15-guoren@kernel.org
Changes since v2:
- line up the comments [Andrew]
- rename SAVE_ALL as SAVE_ABI_REGS [Guo Ren]
- consolidate the modifications of mcount-dyn.S into one patch [Guo Ren]
- adapt this series based on [riscv: ftrace: Fixup ftrace detour code][1] [Guo Ren]
[1]: https://lore.kernel.org/linux-riscv/20220921034910.3142465-1-guoren@kernel.org/
v2 Link: https://lore.kernel.org/linux-riscv/20221116031305.286634-1-suagrfillet@gmail.com/
Changes since v1:
- fix the checkpatch warnings in patch 1
v1 Link: https://lore.kernel.org/linux-riscv/20221115061525.112757-1-suagrfillet@gmail.com
Song Shuai (2):
riscv/ftrace: add ftrace_graph_func
riscv/ftrace: make ftrace_caller call ftrace_graph_func
arch/riscv/include/asm/ftrace.h | 13 ++-
arch/riscv/kernel/ftrace.c | 30 +++----
arch/riscv/kernel/mcount-dyn.S | 143 +++++++++++++++++++++++---------
3 files changed, 129 insertions(+), 57 deletions(-)
--
2.20.1
^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH v3 1/2] riscv/ftrace: add ftrace_graph_func 2022-11-18 17:32 [PATCH v3 0/2] riscv/ftrace: make function graph use ftrace directly Song Shuai @ 2022-11-18 17:32 ` Song Shuai 2022-11-18 17:32 ` [PATCH v3 2/2] riscv/ftrace: make ftrace_caller call ftrace_graph_func Song Shuai 2022-11-20 4:26 ` [PATCH v3 0/2] riscv/ftrace: make function graph use ftrace directly Guo Ren 2 siblings, 0 replies; 6+ messages in thread From: Song Shuai @ 2022-11-18 17:32 UTC (permalink / raw) To: guoren, rostedt, mhiramat, mark.rutland, paul.walmsley, palmer, aou Cc: linux-riscv, linux-kernel, Song Shuai Here implements ftrace_graph_func as the function graph tracing function with FTRACE_WITH_REGS defined. function_graph_func gets the point of the parent IP and the frame pointer from fregs and call prepare_ftrace_return for function graph tracing. If FTRACE_WITH_REGS isn't defined, the enable/disable helpers of ftrace_graph_[regs]_call are revised for serving only ftrace_graph_call in the !FTRACE_WITH_REGS version ftrace_caller. Signed-off-by: Song Shuai <suagrfillet@gmail.com> --- arch/riscv/include/asm/ftrace.h | 13 +++++++++++-- arch/riscv/kernel/ftrace.c | 30 +++++++++++++----------------- 2 files changed, 24 insertions(+), 19 deletions(-) diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h index 34b0b523865a..01bebb28eabe 100644 --- a/arch/riscv/include/asm/ftrace.h +++ b/arch/riscv/include/asm/ftrace.h @@ -107,8 +107,17 @@ do { \ struct dyn_ftrace; int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec); #define ftrace_init_nop ftrace_init_nop -#endif -#endif +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS +struct ftrace_ops; +struct ftrace_regs; +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct ftrace_regs *fregs); +#define ftrace_graph_func ftrace_graph_func +#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ + +#endif /* __ASSEMBLY__ */ + +#endif /* CONFIG_DYNAMIC_FTRACE */ #endif /* _ASM_RISCV_FTRACE_H */ diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c index 8c77f236fc71..651ce5808b77 100644 --- a/arch/riscv/kernel/ftrace.c +++ b/arch/riscv/kernel/ftrace.c @@ -169,32 +169,28 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, } #ifdef CONFIG_DYNAMIC_FTRACE +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS +void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct ftrace_regs *fregs) +{ + struct pt_regs *regs = arch_ftrace_get_regs(fregs); + unsigned long *parent = (unsigned long *)®s->ra; + + prepare_ftrace_return(parent, ip, frame_pointer(regs)); +} +#else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ extern void ftrace_graph_call(void); -extern void ftrace_graph_regs_call(void); int ftrace_enable_ftrace_graph_caller(void) { - int ret; - - ret = __ftrace_modify_call((unsigned long)&ftrace_graph_call, - (unsigned long)&prepare_ftrace_return, true, true); - if (ret) - return ret; - - return __ftrace_modify_call((unsigned long)&ftrace_graph_regs_call, + return __ftrace_modify_call((unsigned long)&ftrace_graph_call, (unsigned long)&prepare_ftrace_return, true, true); } int ftrace_disable_ftrace_graph_caller(void) { - int ret; - - ret = __ftrace_modify_call((unsigned long)&ftrace_graph_call, - (unsigned long)&prepare_ftrace_return, false, true); - if (ret) - return ret; - - return __ftrace_modify_call((unsigned long)&ftrace_graph_regs_call, + return __ftrace_modify_call((unsigned long)&ftrace_graph_call, (unsigned long)&prepare_ftrace_return, false, true); } +#endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ #endif /* CONFIG_DYNAMIC_FTRACE */ #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ -- 2.20.1 ^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v3 2/2] riscv/ftrace: make ftrace_caller call ftrace_graph_func 2022-11-18 17:32 [PATCH v3 0/2] riscv/ftrace: make function graph use ftrace directly Song Shuai 2022-11-18 17:32 ` [PATCH v3 1/2] riscv/ftrace: add ftrace_graph_func Song Shuai @ 2022-11-18 17:32 ` Song Shuai 2022-11-20 3:38 ` Guo Ren 2022-11-20 4:26 ` [PATCH v3 0/2] riscv/ftrace: make function graph use ftrace directly Guo Ren 2 siblings, 1 reply; 6+ messages in thread From: Song Shuai @ 2022-11-18 17:32 UTC (permalink / raw) To: guoren, rostedt, mhiramat, mark.rutland, paul.walmsley, palmer, aou Cc: linux-riscv, linux-kernel, Song Shuai In order to make the function graph use ftrace directly, ftrace_caller should be adjusted to save the necessary regs against the pt_regs layout so it can call ftrace_graph_func reasonably. SAVE_ALL now saves all the regs according to the pt_regs struct. Here supersedes SAVE_ALL by SAVE_ABI_REGS which has an extra option to allow saving only the necessary ABI-related regs for ftrace_caller. ftrace_caller and ftrace_regs_caller save their regs with the respective option of SAVE_ABI_REGS, then call the tracing function, especially graph_ops's ftrace_graph_func. So the ftrace_graph_[regs]_call labels aren't needed anymore if FTRACE_WITH_REGS is defined. As the previous patch described, the ftrace_caller remains with its ftrace_graph_call if FTRACE_WITH_REGS isn't defined, For convenience, the original argument setup for the tracing function in ftrace_[regs]_caller is killed and appended to the tail of SAVE_ABI_REGS. Signed-off-by: Song Shuai <suagrfillet@gmail.com> --- arch/riscv/kernel/mcount-dyn.S | 143 ++++++++++++++++++++++++--------- 1 file changed, 105 insertions(+), 38 deletions(-) diff --git a/arch/riscv/kernel/mcount-dyn.S b/arch/riscv/kernel/mcount-dyn.S index 64bc79816f5e..c70f04711a2e 100644 --- a/arch/riscv/kernel/mcount-dyn.S +++ b/arch/riscv/kernel/mcount-dyn.S @@ -57,19 +57,55 @@ .endm #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS - .macro SAVE_ALL + +/** +* SAVE_ABI_REGS - save regs against the pt_regs struct +* +* @all: tell if saving all the regs +* +* If all is set, all the regs will be saved, otherwise only ABI +* related regs (a0-a7,epc,ra and optional s0) will be saved. +* +* For convenience the argument setup for tracing function is appended here. +* Especially $sp is passed as the 4th argument of the tracing function. +* +* After the stack is established, +* +* 0(sp) stores the PC of the traced function which can be accessed +* by &(fregs)->regs->epc in tracing function. Note that the real +* function entry address should be computed with -FENTRY_RA_OFFSET. +* +* 8(sp) stores the function return address (i.e. parent IP) that +* can be accessed by &(fregs)->regs->ra in tracing function. +* +* The other regs are saved at the respective localtion and accessed +* by the respective pt_regs member. +* +* Here is the layout of stack for your reference. +* +* PT_SIZE_ON_STACK -> +++++++++ +* + ..... + +* + t3-t6 + +* + s2-s11+ +* + a0-a7 + --++++-> ftrace_caller saved +* + s1 + + +* + s0 + --+ +* + t0-t2 + + +* + tp + + +* + gp + + +* + sp + + +* + ra + --+ // parent IP +* sp -> + epc + --+ // PC +* +++++++++ +**/ + .macro SAVE_ABI_REGS, all=0 addi sp, sp, -PT_SIZE_ON_STACK REG_S t0, PT_EPC(sp) REG_S x1, PT_RA(sp) - REG_S x2, PT_SP(sp) - REG_S x3, PT_GP(sp) - REG_S x4, PT_TP(sp) - REG_S x5, PT_T0(sp) - REG_S x6, PT_T1(sp) - REG_S x7, PT_T2(sp) - REG_S x8, PT_S0(sp) - REG_S x9, PT_S1(sp) + + // always save the ABI regs + REG_S x10, PT_A0(sp) REG_S x11, PT_A1(sp) REG_S x12, PT_A2(sp) @@ -78,6 +114,18 @@ REG_S x15, PT_A5(sp) REG_S x16, PT_A6(sp) REG_S x17, PT_A7(sp) + + // save the leftover regs + + .if \all == 1 + REG_S x2, PT_SP(sp) + REG_S x3, PT_GP(sp) + REG_S x4, PT_TP(sp) + REG_S x5, PT_T0(sp) + REG_S x6, PT_T1(sp) + REG_S x7, PT_T2(sp) + REG_S x8, PT_S0(sp) + REG_S x9, PT_S1(sp) REG_S x18, PT_S2(sp) REG_S x19, PT_S3(sp) REG_S x20, PT_S4(sp) @@ -92,19 +140,28 @@ REG_S x29, PT_T4(sp) REG_S x30, PT_T5(sp) REG_S x31, PT_T6(sp) + + // save s0 if FP_TEST defined + + .else +#ifdef HAVE_FUNCTION_GRAPH_FP_TEST + REG_S x8, PT_S0(sp) +#endif + .endif + + // setup 4 args for tracing functions + + addi a0, t0, -FENTRY_RA_OFFSET // ip + la a1, function_trace_op + REG_L a2, 0(a1) // op + REG_L a1, PT_RA(sp) // parent_ip + mv a3, sp // fregs + .endm - .macro RESTORE_ALL + .macro RESTORE_ABI_REGS, all=0 REG_L t0, PT_EPC(sp) REG_L x1, PT_RA(sp) - REG_L x2, PT_SP(sp) - REG_L x3, PT_GP(sp) - REG_L x4, PT_TP(sp) - REG_L x5, PT_T0(sp) - REG_L x6, PT_T1(sp) - REG_L x7, PT_T2(sp) - REG_L x8, PT_S0(sp) - REG_L x9, PT_S1(sp) REG_L x10, PT_A0(sp) REG_L x11, PT_A1(sp) REG_L x12, PT_A2(sp) @@ -113,6 +170,16 @@ REG_L x15, PT_A5(sp) REG_L x16, PT_A6(sp) REG_L x17, PT_A7(sp) + + .if \all == 1 + REG_L x2, PT_SP(sp) + REG_L x3, PT_GP(sp) + REG_L x4, PT_TP(sp) + REG_L x5, PT_T0(sp) + REG_L x6, PT_T1(sp) + REG_L x7, PT_T2(sp) + REG_L x8, PT_S0(sp) + REG_L x9, PT_S1(sp) REG_L x18, PT_S2(sp) REG_L x19, PT_S3(sp) REG_L x20, PT_S4(sp) @@ -128,10 +195,16 @@ REG_L x30, PT_T5(sp) REG_L x31, PT_T6(sp) + .else +#ifdef HAVE_FUNCTION_GRAPH_FP_TEST + REG_L x8, PT_S0(sp) +#endif + .endif addi sp, sp, PT_SIZE_ON_STACK .endm #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ +#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS ENTRY(ftrace_caller) SAVE_ABI @@ -160,33 +233,27 @@ ftrace_graph_call: jr t0 ENDPROC(ftrace_caller) -#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS +#else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ ENTRY(ftrace_regs_caller) - SAVE_ALL - - addi a0, t0, -FENTRY_RA_OFFSET - la a1, function_trace_op - REG_L a2, 0(a1) - REG_L a1, PT_RA(sp) - mv a3, sp + SAVE_ABI_REGS 1 ftrace_regs_call: .global ftrace_regs_call call ftrace_stub -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - addi a0, sp, PT_RA - REG_L a1, PT_T0(sp) - addi a1, a1, -FENTRY_RA_OFFSET -#ifdef HAVE_FUNCTION_GRAPH_FP_TEST - mv a2, s0 -#endif -ftrace_graph_regs_call: - .global ftrace_graph_regs_call - call ftrace_stub -#endif - RESTORE_ALL + RESTORE_ABI_REGS 1 jr t0 ENDPROC(ftrace_regs_caller) + +ENTRY(ftrace_caller) + SAVE_ABI_REGS 0 + +ftrace_call: + .global ftrace_call + call ftrace_stub + + RESTORE_ABI_REGS 0 + jr t0 +ENDPROC(ftrace_caller) #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ -- 2.20.1 ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3 2/2] riscv/ftrace: make ftrace_caller call ftrace_graph_func 2022-11-18 17:32 ` [PATCH v3 2/2] riscv/ftrace: make ftrace_caller call ftrace_graph_func Song Shuai @ 2022-11-20 3:38 ` Guo Ren 0 siblings, 0 replies; 6+ messages in thread From: Guo Ren @ 2022-11-20 3:38 UTC (permalink / raw) To: Song Shuai Cc: rostedt, mhiramat, mark.rutland, paul.walmsley, palmer, aou, linux-riscv, linux-kernel On Sat, Nov 19, 2022 at 1:32 AM Song Shuai <suagrfillet@gmail.com> wrote: > > In order to make the function graph use ftrace directly, ftrace_caller > should be adjusted to save the necessary regs against the pt_regs layout > so it can call ftrace_graph_func reasonably. > > SAVE_ALL now saves all the regs according to the pt_regs struct. Here > supersedes SAVE_ALL by SAVE_ABI_REGS which has an extra option to allow > saving only the necessary ABI-related regs for ftrace_caller. > > ftrace_caller and ftrace_regs_caller save their regs with the respective > option of SAVE_ABI_REGS, then call the tracing function, especially > graph_ops's ftrace_graph_func. So the ftrace_graph_[regs]_call labels > aren't needed anymore if FTRACE_WITH_REGS is defined. > > As the previous patch described, the ftrace_caller remains with its > ftrace_graph_call if FTRACE_WITH_REGS isn't defined, > > For convenience, the original argument setup for the tracing function in > ftrace_[regs]_caller is killed and appended to the tail of SAVE_ABI_REGS. > > Signed-off-by: Song Shuai <suagrfillet@gmail.com> > --- > arch/riscv/kernel/mcount-dyn.S | 143 ++++++++++++++++++++++++--------- > 1 file changed, 105 insertions(+), 38 deletions(-) > > diff --git a/arch/riscv/kernel/mcount-dyn.S b/arch/riscv/kernel/mcount-dyn.S > index 64bc79816f5e..c70f04711a2e 100644 > --- a/arch/riscv/kernel/mcount-dyn.S > +++ b/arch/riscv/kernel/mcount-dyn.S > @@ -57,19 +57,55 @@ > .endm > > #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS > - .macro SAVE_ALL > + > +/** > +* SAVE_ABI_REGS - save regs against the pt_regs struct > +* > +* @all: tell if saving all the regs > +* > +* If all is set, all the regs will be saved, otherwise only ABI > +* related regs (a0-a7,epc,ra and optional s0) will be saved. > +* > +* For convenience the argument setup for tracing function is appended here. > +* Especially $sp is passed as the 4th argument of the tracing function. > +* > +* After the stack is established, > +* > +* 0(sp) stores the PC of the traced function which can be accessed > +* by &(fregs)->regs->epc in tracing function. Note that the real > +* function entry address should be computed with -FENTRY_RA_OFFSET. > +* > +* 8(sp) stores the function return address (i.e. parent IP) that > +* can be accessed by &(fregs)->regs->ra in tracing function. > +* > +* The other regs are saved at the respective localtion and accessed > +* by the respective pt_regs member. > +* > +* Here is the layout of stack for your reference. > +* > +* PT_SIZE_ON_STACK -> +++++++++ > +* + ..... + > +* + t3-t6 + > +* + s2-s11+ > +* + a0-a7 + --++++-> ftrace_caller saved > +* + s1 + + > +* + s0 + --+ > +* + t0-t2 + + > +* + tp + + > +* + gp + + > +* + sp + + > +* + ra + --+ // parent IP > +* sp -> + epc + --+ // PC > +* +++++++++ > +**/ > + .macro SAVE_ABI_REGS, all=0 > addi sp, sp, -PT_SIZE_ON_STACK > > REG_S t0, PT_EPC(sp) > REG_S x1, PT_RA(sp) > - REG_S x2, PT_SP(sp) > - REG_S x3, PT_GP(sp) > - REG_S x4, PT_TP(sp) > - REG_S x5, PT_T0(sp) > - REG_S x6, PT_T1(sp) > - REG_S x7, PT_T2(sp) > - REG_S x8, PT_S0(sp) > - REG_S x9, PT_S1(sp) > + > + // always save the ABI regs > + > REG_S x10, PT_A0(sp) > REG_S x11, PT_A1(sp) > REG_S x12, PT_A2(sp) > @@ -78,6 +114,18 @@ > REG_S x15, PT_A5(sp) > REG_S x16, PT_A6(sp) > REG_S x17, PT_A7(sp) > + > + // save the leftover regs > + > + .if \all == 1 > + REG_S x2, PT_SP(sp) > + REG_S x3, PT_GP(sp) > + REG_S x4, PT_TP(sp) > + REG_S x5, PT_T0(sp) > + REG_S x6, PT_T1(sp) > + REG_S x7, PT_T2(sp) > + REG_S x8, PT_S0(sp) > + REG_S x9, PT_S1(sp) > REG_S x18, PT_S2(sp) > REG_S x19, PT_S3(sp) > REG_S x20, PT_S4(sp) > @@ -92,19 +140,28 @@ > REG_S x29, PT_T4(sp) > REG_S x30, PT_T5(sp) > REG_S x31, PT_T6(sp) > + > + // save s0 if FP_TEST defined > + > + .else > +#ifdef HAVE_FUNCTION_GRAPH_FP_TEST > + REG_S x8, PT_S0(sp) > +#endif > + .endif > + > + // setup 4 args for tracing functions > + > + addi a0, t0, -FENTRY_RA_OFFSET // ip > + la a1, function_trace_op > + REG_L a2, 0(a1) // op > + REG_L a1, PT_RA(sp) // parent_ip > + mv a3, sp // fregs Moving parameters preparation into SAVE_ABI_REGS is not a good idea. Give them a separate .macro: PREPARE_ARGS. > + > .endm > > - .macro RESTORE_ALL > + .macro RESTORE_ABI_REGS, all=0 > REG_L t0, PT_EPC(sp) > REG_L x1, PT_RA(sp) > - REG_L x2, PT_SP(sp) > - REG_L x3, PT_GP(sp) > - REG_L x4, PT_TP(sp) > - REG_L x5, PT_T0(sp) > - REG_L x6, PT_T1(sp) > - REG_L x7, PT_T2(sp) > - REG_L x8, PT_S0(sp) > - REG_L x9, PT_S1(sp) > REG_L x10, PT_A0(sp) > REG_L x11, PT_A1(sp) > REG_L x12, PT_A2(sp) > @@ -113,6 +170,16 @@ > REG_L x15, PT_A5(sp) > REG_L x16, PT_A6(sp) > REG_L x17, PT_A7(sp) > + > + .if \all == 1 > + REG_L x2, PT_SP(sp) > + REG_L x3, PT_GP(sp) > + REG_L x4, PT_TP(sp) > + REG_L x5, PT_T0(sp) > + REG_L x6, PT_T1(sp) > + REG_L x7, PT_T2(sp) > + REG_L x8, PT_S0(sp) > + REG_L x9, PT_S1(sp) > REG_L x18, PT_S2(sp) > REG_L x19, PT_S3(sp) > REG_L x20, PT_S4(sp) > @@ -128,10 +195,16 @@ > REG_L x30, PT_T5(sp) > REG_L x31, PT_T6(sp) > > + .else > +#ifdef HAVE_FUNCTION_GRAPH_FP_TEST > + REG_L x8, PT_S0(sp) > +#endif > + .endif > addi sp, sp, PT_SIZE_ON_STACK > .endm > #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ > > +#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS > ENTRY(ftrace_caller) > SAVE_ABI > > @@ -160,33 +233,27 @@ ftrace_graph_call: > jr t0 > ENDPROC(ftrace_caller) > > -#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS > +#else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ > ENTRY(ftrace_regs_caller) > - SAVE_ALL > - > - addi a0, t0, -FENTRY_RA_OFFSET > - la a1, function_trace_op > - REG_L a2, 0(a1) > - REG_L a1, PT_RA(sp) > - mv a3, sp > + SAVE_ABI_REGS 1 > > ftrace_regs_call: > .global ftrace_regs_call > call ftrace_stub > > -#ifdef CONFIG_FUNCTION_GRAPH_TRACER > - addi a0, sp, PT_RA > - REG_L a1, PT_T0(sp) > - addi a1, a1, -FENTRY_RA_OFFSET > -#ifdef HAVE_FUNCTION_GRAPH_FP_TEST > - mv a2, s0 > -#endif > -ftrace_graph_regs_call: > - .global ftrace_graph_regs_call > - call ftrace_stub > -#endif > > - RESTORE_ALL > + RESTORE_ABI_REGS 1 > jr t0 > ENDPROC(ftrace_regs_caller) > + > +ENTRY(ftrace_caller) > + SAVE_ABI_REGS 0 > + > +ftrace_call: > + .global ftrace_call > + call ftrace_stub > + > + RESTORE_ABI_REGS 0 > + jr t0 > +ENDPROC(ftrace_caller) > #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ > -- > 2.20.1 > -- Best Regards Guo Ren ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3 0/2] riscv/ftrace: make function graph use ftrace directly 2022-11-18 17:32 [PATCH v3 0/2] riscv/ftrace: make function graph use ftrace directly Song Shuai 2022-11-18 17:32 ` [PATCH v3 1/2] riscv/ftrace: add ftrace_graph_func Song Shuai 2022-11-18 17:32 ` [PATCH v3 2/2] riscv/ftrace: make ftrace_caller call ftrace_graph_func Song Shuai @ 2022-11-20 4:26 ` Guo Ren 2022-11-20 9:12 ` Song Shuai 2 siblings, 1 reply; 6+ messages in thread From: Guo Ren @ 2022-11-20 4:26 UTC (permalink / raw) To: Song Shuai Cc: rostedt, mhiramat, mark.rutland, paul.walmsley, palmer, aou, linux-riscv, linux-kernel On Sat, Nov 19, 2022 at 1:32 AM Song Shuai <suagrfillet@gmail.com> wrote: > > In RISC-V architecture, when we enable the ftrace_graph tracer on some > functions, the function tracings on other functions will suffer extra > graph tracing work. In essence, graph_ops isn't limited by its func_hash > due to the global ftrace_graph_[regs]_call label. That should be corrected. > > What inspires me is the commit 0c0593b45c9b ("x86/ftrace: Make function > graph use ftrace directly") that uses graph_ops::func function to install > return_hooker and makes the function called against its func_hash. > > This series of patches makes function graph use ftrace directly for riscv. > > If FTRACE_WITH_REGS isn't defined, ftrace_caller keeps ftrace_graph_call > so that it can be replaced with the calling of prepare_ftrace_return by > the enable/disable helper. > > As for defining FTRACE_WITH_REGS, ftrace_caller is adjusted to save the > necessary regs against the pt_regs layout, so it can reasonably call the > graph_ops::func function - ftrace_graph_func. And ftrace_graph_[regs]_call > and its enable/disable helper aren't needed. > > The tests generated by CONFIG_FTRACE_STARTUP_TEST have passed in the local > qemu-system-riscv64 virt machine. The following is the log during startup. > > ``` > Nov 15 03:07:13 stage4 kernel: Testing tracer function: PASSED > Nov 15 03:07:13 stage4 kernel: Testing dynamic ftrace: PASSED > Nov 15 03:07:13 stage4 kernel: Testing dynamic ftrace ops #1: > Nov 15 03:07:13 stage4 kernel: (1 0 1 0 0) > Nov 15 03:07:13 stage4 kernel: (1 1 2 0 0) > Nov 15 03:07:13 stage4 kernel: (2 1 3 0 365) > Nov 15 03:07:13 stage4 kernel: (2 2 4 0 399) > Nov 15 03:07:13 stage4 kernel: (3 2 4 0 146071) > Nov 15 03:07:13 stage4 kernel: (3 3 5 0 146105) PASSED > Nov 15 03:07:13 stage4 kernel: Testing dynamic ftrace ops #2: > Nov 15 03:07:13 stage4 kernel: (1 0 1 589 0) > Nov 15 03:07:13 stage4 kernel: (1 1 2 635 0) > Nov 15 03:07:13 stage4 kernel: (2 1 3 1 2) > Nov 15 03:07:13 stage4 kernel: (2 2 4 125 126) > Nov 15 03:07:13 stage4 kernel: (3 2 4 146001 146078) > Nov 15 03:07:13 stage4 kernel: (3 3 5 146035 146112) PASSED > Nov 15 03:07:13 stage4 kernel: Testing ftrace recursion: PASSED > Nov 15 03:07:13 stage4 kernel: Testing ftrace recursion safe: PASSED > Nov 15 03:07:13 stage4 kernel: Testing ftrace regs: PASSED > Nov 15 03:07:13 stage4 kernel: Testing tracer nop: PASSED > Nov 15 03:07:13 stage4 kernel: Testing tracer irqsoff: PASSED > Nov 15 03:07:13 stage4 kernel: Testing tracer wakeup: > Nov 15 03:07:13 stage4 kernel: sched: DL replenish lagged too much > Nov 15 03:07:13 stage4 kernel: PASSED > Nov 15 03:07:13 stage4 kernel: Testing tracer wakeup_rt: PASSED > Nov 15 03:07:13 stage4 kernel: Testing tracer wakeup_dl: PASSED > Nov 15 03:07:13 stage4 kernel: Testing tracer function_graph: PASSED > ``` > > Note that the changes of mcount-dyn.S conflicts with this unmerged > commit (riscv: entry: consolidate general regs saving/restoring). > https://lore.kernel.org/linux-riscv/20221103075047.1634923-15-guoren@kernel.org > > Changes since v2: > - line up the comments [Andrew] > - rename SAVE_ALL as SAVE_ABI_REGS [Guo Ren] > - consolidate the modifications of mcount-dyn.S into one patch [Guo Ren] > - adapt this series based on [riscv: ftrace: Fixup ftrace detour code][1] [Guo Ren] Tested-by: Guo Ren <guoren@kernel.org> https://github.com/guoren83/linux/tree/ftrace_fixup_v3 > > [1]: https://lore.kernel.org/linux-riscv/20220921034910.3142465-1-guoren@kernel.org/ > v2 Link: https://lore.kernel.org/linux-riscv/20221116031305.286634-1-suagrfillet@gmail.com/ > > Changes since v1: > - fix the checkpatch warnings in patch 1 > v1 Link: https://lore.kernel.org/linux-riscv/20221115061525.112757-1-suagrfillet@gmail.com > > Song Shuai (2): > riscv/ftrace: add ftrace_graph_func > riscv/ftrace: make ftrace_caller call ftrace_graph_func > > arch/riscv/include/asm/ftrace.h | 13 ++- > arch/riscv/kernel/ftrace.c | 30 +++---- > arch/riscv/kernel/mcount-dyn.S | 143 +++++++++++++++++++++++--------- > 3 files changed, 129 insertions(+), 57 deletions(-) > > -- > 2.20.1 > -- Best Regards Guo Ren ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3 0/2] riscv/ftrace: make function graph use ftrace directly 2022-11-20 4:26 ` [PATCH v3 0/2] riscv/ftrace: make function graph use ftrace directly Guo Ren @ 2022-11-20 9:12 ` Song Shuai 0 siblings, 0 replies; 6+ messages in thread From: Song Shuai @ 2022-11-20 9:12 UTC (permalink / raw) To: Guo Ren Cc: rostedt, mhiramat, mark.rutland, paul.walmsley, palmer, aou, linux-riscv, linux-kernel Guo Ren <guoren@kernel.org> 于2022年11月20日周日 04:26写道： > > On Sat, Nov 19, 2022 at 1:32 AM Song Shuai <suagrfillet@gmail.com> wrote: > > > > In RISC-V architecture, when we enable the ftrace_graph tracer on some > > functions, the function tracings on other functions will suffer extra > > graph tracing work. In essence, graph_ops isn't limited by its func_hash > > due to the global ftrace_graph_[regs]_call label. That should be corrected. > > > > What inspires me is the commit 0c0593b45c9b ("x86/ftrace: Make function > > graph use ftrace directly") that uses graph_ops::func function to install > > return_hooker and makes the function called against its func_hash. > > > > This series of patches makes function graph use ftrace directly for riscv. > > > > If FTRACE_WITH_REGS isn't defined, ftrace_caller keeps ftrace_graph_call > > so that it can be replaced with the calling of prepare_ftrace_return by > > the enable/disable helper. > > > > As for defining FTRACE_WITH_REGS, ftrace_caller is adjusted to save the > > necessary regs against the pt_regs layout, so it can reasonably call the > > graph_ops::func function - ftrace_graph_func. And ftrace_graph_[regs]_call > > and its enable/disable helper aren't needed. > > > > The tests generated by CONFIG_FTRACE_STARTUP_TEST have passed in the local > > qemu-system-riscv64 virt machine. The following is the log during startup. > > > > ``` > > Nov 15 03:07:13 stage4 kernel: Testing tracer function: PASSED > > Nov 15 03:07:13 stage4 kernel: Testing dynamic ftrace: PASSED > > Nov 15 03:07:13 stage4 kernel: Testing dynamic ftrace ops #1: > > Nov 15 03:07:13 stage4 kernel: (1 0 1 0 0) > > Nov 15 03:07:13 stage4 kernel: (1 1 2 0 0) > > Nov 15 03:07:13 stage4 kernel: (2 1 3 0 365) > > Nov 15 03:07:13 stage4 kernel: (2 2 4 0 399) > > Nov 15 03:07:13 stage4 kernel: (3 2 4 0 146071) > > Nov 15 03:07:13 stage4 kernel: (3 3 5 0 146105) PASSED > > Nov 15 03:07:13 stage4 kernel: Testing dynamic ftrace ops #2: > > Nov 15 03:07:13 stage4 kernel: (1 0 1 589 0) > > Nov 15 03:07:13 stage4 kernel: (1 1 2 635 0) > > Nov 15 03:07:13 stage4 kernel: (2 1 3 1 2) > > Nov 15 03:07:13 stage4 kernel: (2 2 4 125 126) > > Nov 15 03:07:13 stage4 kernel: (3 2 4 146001 146078) > > Nov 15 03:07:13 stage4 kernel: (3 3 5 146035 146112) PASSED > > Nov 15 03:07:13 stage4 kernel: Testing ftrace recursion: PASSED > > Nov 15 03:07:13 stage4 kernel: Testing ftrace recursion safe: PASSED > > Nov 15 03:07:13 stage4 kernel: Testing ftrace regs: PASSED > > Nov 15 03:07:13 stage4 kernel: Testing tracer nop: PASSED > > Nov 15 03:07:13 stage4 kernel: Testing tracer irqsoff: PASSED > > Nov 15 03:07:13 stage4 kernel: Testing tracer wakeup: > > Nov 15 03:07:13 stage4 kernel: sched: DL replenish lagged too much > > Nov 15 03:07:13 stage4 kernel: PASSED > > Nov 15 03:07:13 stage4 kernel: Testing tracer wakeup_rt: PASSED > > Nov 15 03:07:13 stage4 kernel: Testing tracer wakeup_dl: PASSED > > Nov 15 03:07:13 stage4 kernel: Testing tracer function_graph: PASSED > > ``` > > > > Note that the changes of mcount-dyn.S conflicts with this unmerged > > commit (riscv: entry: consolidate general regs saving/restoring). > > https://lore.kernel.org/linux-riscv/20221103075047.1634923-15-guoren@kernel.org > > > > Changes since v2: > > - line up the comments [Andrew] > > - rename SAVE_ALL as SAVE_ABI_REGS [Guo Ren] > > - consolidate the modifications of mcount-dyn.S into one patch [Guo Ren] > > - adapt this series based on [riscv: ftrace: Fixup ftrace detour code][1] [Guo Ren] > Tested-by: Guo Ren <guoren@kernel.org> > > https://github.com/guoren83/linux/tree/ftrace_fixup_v3 > Thanks for your tests. And the PREPARE_ARGS you suggested has been added in the v4 thread. Here is the link for your convenience. https://lore.kernel.org/linux-riscv/20221120084230.910152-1-suagrfillet@gmail.com/ > > > > [1]: https://lore.kernel.org/linux-riscv/20220921034910.3142465-1-guoren@kernel.org/ > > v2 Link: https://lore.kernel.org/linux-riscv/20221116031305.286634-1-suagrfillet@gmail.com/ > > > > Changes since v1: > > - fix the checkpatch warnings in patch 1 > > v1 Link: https://lore.kernel.org/linux-riscv/20221115061525.112757-1-suagrfillet@gmail.com > > > > Song Shuai (2): > > riscv/ftrace: add ftrace_graph_func > > riscv/ftrace: make ftrace_caller call ftrace_graph_func > > > > arch/riscv/include/asm/ftrace.h | 13 ++- > > arch/riscv/kernel/ftrace.c | 30 +++---- > > arch/riscv/kernel/mcount-dyn.S | 143 +++++++++++++++++++++++--------- > > 3 files changed, 129 insertions(+), 57 deletions(-) > > > > -- > > 2.20.1 > > > > > -- > Best Regards > Guo Ren Thanks, Song ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-11-20 9:12 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2022-11-18 17:32 [PATCH v3 0/2] riscv/ftrace: make function graph use ftrace directly Song Shuai 2022-11-18 17:32 ` [PATCH v3 1/2] riscv/ftrace: add ftrace_graph_func Song Shuai 2022-11-18 17:32 ` [PATCH v3 2/2] riscv/ftrace: make ftrace_caller call ftrace_graph_func Song Shuai 2022-11-20 3:38 ` Guo Ren 2022-11-20 4:26 ` [PATCH v3 0/2] riscv/ftrace: make function graph use ftrace directly Guo Ren 2022-11-20 9:12 ` Song Shuai
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