From: Heiko Carstens <hca@linux.ibm.com>
To: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>,
Steven Rostedt <rostedt@goodmis.org>,
Florent Revest <revest@chromium.org>,
linux-trace-kernel@vger.kernel.org,
LKML <linux-kernel@vger.kernel.org>,
Martin KaFai Lau <martin.lau@linux.dev>,
bpf <bpf@vger.kernel.org>, Alexei Starovoitov <ast@kernel.org>,
Jiri Olsa <jolsa@kernel.org>,
Alan Maguire <alan.maguire@oracle.com>,
Mark Rutland <mark.rutland@arm.com>,
linux-arch@vger.kernel.org,
Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will@kernel.org>,
Huacai Chen <chenhuacai@kernel.org>,
WANG Xuerui <kernel@xen0n.name>,
Paul Walmsley <paul.walmsley@sifive.com>,
Palmer Dabbelt <palmer@dabbelt.com>,
Albert Ou <aou@eecs.berkeley.edu>,
Vasily Gorbik <gor@linux.ibm.com>,
Alexander Gordeev <agordeev@linux.ibm.com>,
Christian Borntraeger <borntraeger@linux.ibm.com>,
Sven Schnelle <svens@linux.ibm.com>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Subject: Re: [PATCH v16 04/18] function_graph: Replace fgraph_ret_regs with ftrace_regs
Date: Tue, 15 Oct 2024 20:39:06 +0200 [thread overview]
Message-ID: <20241015183906.19678-B-hca@linux.ibm.com> (raw)
In-Reply-To: <172895575716.107311.6784997045170009035.stgit@devnote2>
On Tue, Oct 15, 2024 at 10:29:17AM +0900, Masami Hiramatsu (Google) wrote:
> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
>
> Use ftrace_regs instead of fgraph_ret_regs for tracing return value
> on function_graph tracer because of simplifying the callback interface.
>
> The CONFIG_HAVE_FUNCTION_GRAPH_RETVAL is also replaced by
> CONFIG_HAVE_FUNCTION_GRAPH_FREGS.
>
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
...
> diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S
> index 7e267ef63a7f..a9ca56ea0858 100644
> --- a/arch/s390/kernel/mcount.S
> +++ b/arch/s390/kernel/mcount.S
> @@ -134,14 +134,15 @@ SYM_CODE_END(ftrace_common)
> SYM_FUNC_START(return_to_handler)
> stmg %r2,%r5,32(%r15)
> lgr %r1,%r15
> - aghi %r15,-(STACK_FRAME_OVERHEAD+__FGRAPH_RET_SIZE)
> + aghi %r15,-(STACK_FRAME_OVERHEAD+STACK_FRAME_SIZE_FREGS)
> stg %r1,__SF_BACKCHAIN(%r15)
> - la %r3,STACK_FRAME_OVERHEAD(%r15)
> - stg %r1,__FGRAPH_RET_FP(%r3)
> - stg %r2,__FGRAPH_RET_GPR2(%r3)
> - lgr %r2,%r3
> + la %r4,STACK_FRAME_OVERHEAD(%r15)
> + stg %r2,__PT_R2(%r4)
> + stg %r3,__PT_R3(%r4)
> + stg %r1,__PT_R15(%r4)
> + lgr %r2,%r4
> brasl %r14,ftrace_return_to_handler
> - aghi %r15,STACK_FRAME_OVERHEAD+__FGRAPH_RET_SIZE
> + aghi %r15,STACK_FRAME_SIZE_FREGS
> lgr %r14,%r2
> lmg %r2,%r5,32(%r15)
> BR_EX %r14
Why didn't you simply merge the addon patch which I provided, and
which I tested?
https://lore.kernel.org/all/20240916121656.20933-B-hca@linux.ibm.com
That would make things much simpler... e.g. your new patch is also
writing r3 to fregs, why? The stackframe allocation is also wrong.
I didn't try, but I guess the above code would crash instantly.
next prev parent reply other threads:[~2024-10-15 18:39 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-10-15 1:28 [PATCH v16 00/18] tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph Masami Hiramatsu (Google)
2024-10-15 1:28 ` [PATCH v16 01/18] tracing: Use arch_ftrace_regs() for ftrace_regs_*() macros Masami Hiramatsu (Google)
2024-10-15 21:27 ` Steven Rostedt
2024-10-15 23:25 ` Masami Hiramatsu
2024-10-15 23:28 ` Steven Rostedt
2024-10-15 1:28 ` [PATCH v16 02/18] tracing: Rename ftrace_regs_return_value to ftrace_regs_get_return_value Masami Hiramatsu (Google)
2024-10-15 1:29 ` [PATCH v16 03/18] function_graph: Pass ftrace_regs to entryfunc Masami Hiramatsu (Google)
2024-10-15 1:29 ` [PATCH v16 04/18] function_graph: Replace fgraph_ret_regs with ftrace_regs Masami Hiramatsu (Google)
2024-10-15 18:39 ` Heiko Carstens [this message]
2024-10-15 23:33 ` Masami Hiramatsu
2024-10-15 23:47 ` Masami Hiramatsu
2024-10-16 8:33 ` Heiko Carstens
2024-10-21 4:22 ` Masami Hiramatsu
2024-10-15 1:29 ` [PATCH v16 05/18] function_graph: Pass ftrace_regs to retfunc Masami Hiramatsu (Google)
2024-10-15 1:29 ` [PATCH v16 06/18] fprobe: Use ftrace_regs in fprobe entry handler Masami Hiramatsu (Google)
2024-10-15 1:29 ` [PATCH v16 07/18] fprobe: Use ftrace_regs in fprobe exit handler Masami Hiramatsu (Google)
2024-10-15 1:30 ` [PATCH v16 08/18] tracing: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs Masami Hiramatsu (Google)
2024-10-15 1:30 ` [PATCH v16 09/18] tracing: Add ftrace_fill_perf_regs() for perf event Masami Hiramatsu (Google)
2024-10-15 18:18 ` Heiko Carstens
2024-10-15 23:34 ` Masami Hiramatsu
2024-10-15 1:30 ` [PATCH v16 10/18] tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS Masami Hiramatsu (Google)
2024-10-15 1:30 ` [PATCH v16 11/18] bpf: Enable kprobe_multi feature if CONFIG_FPROBE is enabled Masami Hiramatsu (Google)
2024-10-15 1:30 ` [PATCH v16 12/18] ftrace: Add CONFIG_HAVE_FTRACE_GRAPH_FUNC Masami Hiramatsu (Google)
2024-10-15 1:31 ` [PATCH v16 13/18] fprobe: Rewrite fprobe on function-graph tracer Masami Hiramatsu (Google)
2024-10-15 1:31 ` [PATCH v16 14/18] tracing/fprobe: Remove nr_maxactive from fprobe Masami Hiramatsu (Google)
2024-10-15 1:31 ` [PATCH v16 15/18] selftests: ftrace: Remove obsolate maxactive syntax check Masami Hiramatsu (Google)
2024-10-15 1:31 ` [PATCH v16 16/18] selftests/ftrace: Add a test case for repeating register/unregister fprobe Masami Hiramatsu (Google)
2024-10-15 1:31 ` [PATCH v16 17/18] Documentation: probes: Update fprobe on function-graph tracer Masami Hiramatsu (Google)
2024-10-15 1:31 ` [PATCH v16 18/18] bpf: Add get_entry_ip() for arm64 Masami Hiramatsu (Google)
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20241015183906.19678-B-hca@linux.ibm.com \
--to=hca@linux.ibm.com \
--cc=agordeev@linux.ibm.com \
--cc=alan.maguire@oracle.com \
--cc=alexei.starovoitov@gmail.com \
--cc=aou@eecs.berkeley.edu \
--cc=ast@kernel.org \
--cc=borntraeger@linux.ibm.com \
--cc=bp@alien8.de \
--cc=bpf@vger.kernel.org \
--cc=catalin.marinas@arm.com \
--cc=chenhuacai@kernel.org \
--cc=dave.hansen@linux.intel.com \
--cc=gor@linux.ibm.com \
--cc=hpa@zytor.com \
--cc=jolsa@kernel.org \
--cc=kernel@xen0n.name \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-trace-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=martin.lau@linux.dev \
--cc=mathieu.desnoyers@efficios.com \
--cc=mhiramat@kernel.org \
--cc=mingo@redhat.com \
--cc=palmer@dabbelt.com \
--cc=paul.walmsley@sifive.com \
--cc=revest@chromium.org \
--cc=rostedt@goodmis.org \
--cc=svens@linux.ibm.com \
--cc=tglx@linutronix.de \
--cc=will@kernel.org \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.