[v2,0/3] riscv/ftrace: make function graph use ftrace directly

Message ID	20221116031305.286634-1-suagrfillet@gmail.com
Headers	Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; From: Song Shuai <suagrfillet@gmail.com> To: guoren@kernel.org, rostedt@goodmis.org, mhiramat@kernel.org, mark.rutland@arm.com, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Song Shuai <suagrfillet@gmail.com> Subject: [PATCH v2 0/3] riscv/ftrace: make function graph use ftrace directly Date: Wed, 16 Nov 2022 11:13:02 +0800 Message-Id: <20221116031305.286634-1-suagrfillet@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	riscv/ftrace: make function graph use ftrace directly \| [v2,0/3] riscv/ftrace: make function graph use ftrace directly [v2,1/3] riscv/ftrace: add ftrace_graph_func [v2,2/3] riscv/ftrace: SAVE_ALL supports lightweight save [v2,3/3] riscv/ftrace: cleanup ftrace_caller and ftrace_regs_caller

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20221116031305.286634-1-suagrfillet@gmail.com

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From: Song Shuai <suagrfillet@gmail.com>
To: guoren@kernel.org, rostedt@goodmis.org, mhiramat@kernel.org,
        mark.rutland@arm.com, paul.walmsley@sifive.com, palmer@dabbelt.com,
        aou@eecs.berkeley.edu
Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        Song Shuai <suagrfillet@gmail.com>
Subject: [PATCH v2 0/3] riscv/ftrace: make function graph use ftrace directly
Date: Wed, 16 Nov 2022 11:13:02 +0800
Message-Id: <20221116031305.286634-1-suagrfillet@gmail.com>
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Series

riscv/ftrace: make function graph use ftrace directly |

Message

Song Shuai Nov. 16, 2022, 3:13 a.m. UTC

  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 v1
-  fixed the checkpatch warnings in patch 1
Link: https://lore.kernel.org/linux-riscv/20221115061525.112757-1-suagrfillet@gmail.com

Song Shuai (3):
  riscv/ftrace: add ftrace_graph_func
  riscv/ftrace: SAVE_ALL supports lightweight save
  riscv/ftrace: cleanup ftrace_caller and ftrace_regs_caller

 arch/riscv/include/asm/ftrace.h |  13 ++-
 arch/riscv/kernel/ftrace.c      |  35 ++++----
 arch/riscv/kernel/mcount-dyn.S  | 145 +++++++++++++++++++++++---------
 3 files changed, 136 insertions(+), 57 deletions(-)

Comments

Guo Ren Nov. 17, 2022, 1:45 a.m. UTC | #1

I hope this series could base on the following:
https://lore.kernel.org/linux-riscv/20220921034910.3142465-4-guoren@kernel.org/

They all modified the mcount-dyn.S.

On Wed, Nov 16, 2022 at 11:13 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 v1
> -  fixed the checkpatch warnings in patch 1
> Link: https://lore.kernel.org/linux-riscv/20221115061525.112757-1-suagrfillet@gmail.com
>
> Song Shuai (3):
>   riscv/ftrace: add ftrace_graph_func
>   riscv/ftrace: SAVE_ALL supports lightweight save
>   riscv/ftrace: cleanup ftrace_caller and ftrace_regs_caller
>
>  arch/riscv/include/asm/ftrace.h |  13 ++-
>  arch/riscv/kernel/ftrace.c      |  35 ++++----
>  arch/riscv/kernel/mcount-dyn.S  | 145 +++++++++++++++++++++++---------
>  3 files changed, 136 insertions(+), 57 deletions(-)
>
> --
> 2.20.1
>


--
Best Regards
 Guo Ren

Song Shuai Nov. 18, 2022, 10:10 a.m. UTC | #2

Guo Ren <guoren@kernel.org> 于2022年11月17日周四 01:46写道：
>
> I hope this series could base on the following:
> https://lore.kernel.org/linux-riscv/20220921034910.3142465-4-guoren@kernel.org/
>
> They all modified the mcount-dyn.S.
Ok, I'll adapt these patches based on the series you mentioned.
>
>
> On Wed, Nov 16, 2022 at 11:13 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 v1
> > -  fixed the checkpatch warnings in patch 1
> > Link: https://lore.kernel.org/linux-riscv/20221115061525.112757-1-suagrfillet@gmail.com
> >
> > Song Shuai (3):
> >   riscv/ftrace: add ftrace_graph_func
> >   riscv/ftrace: SAVE_ALL supports lightweight save
> >   riscv/ftrace: cleanup ftrace_caller and ftrace_regs_caller
> >
> >  arch/riscv/include/asm/ftrace.h |  13 ++-
> >  arch/riscv/kernel/ftrace.c      |  35 ++++----
> >  arch/riscv/kernel/mcount-dyn.S  | 145 +++++++++++++++++++++++---------
> >  3 files changed, 136 insertions(+), 57 deletions(-)
> >
> > --
> > 2.20.1
> >
>
>
> --
> Best Regards
>  Guo Ren

Thanks,
Song