linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
To: Steven Rostedt <rostedt@goodmis.org>,
	Michael Ellerman <mpe@ellerman.id.au>
Cc: <linux-kernel@vger.kernel.org>, <linuxppc-dev@lists.ozlabs.org>
Subject: [RFC PATCH 12/14] powerpc/ftrace: Drop saving LR to stack save area for -mprofile-kernel
Date: Thu, 26 Nov 2020 23:38:49 +0530	[thread overview]
Message-ID: <b40cb303a22f75b85ec0c8d45160e983baff9299.1606412433.git.naveen.n.rao@linux.vnet.ibm.com> (raw)
In-Reply-To: <cover.1606412433.git.naveen.n.rao@linux.vnet.ibm.com>

In -mprofile-kernel variant of ftrace_graph_caller(), we save the
optionally-updated LR address into the stack save area at the end. This
is likely an offshoot of the initial -mprofile-kernel implementation in
gcc emitting the same as part of the -mprofile-kernel instruction
sequence. However, this is not required. Drop it.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/kernel/trace/ftrace_64_mprofile.S | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
index bbe871b47ade58..c5602e9b07faa3 100644
--- a/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
+++ b/arch/powerpc/kernel/trace/ftrace_64_mprofile.S
@@ -310,7 +310,5 @@ _GLOBAL(ftrace_graph_caller)
 	ld	r2, 24(r1)
 
 	addi	r1, r1, SWITCH_FRAME_SIZE
-	mflr	r0
-	std	r0, LRSAVE(r1)
 	bctr
 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-- 
2.25.4


  parent reply	other threads:[~2020-11-26 18:10 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-26 18:08 [RFC PATCH 00/14] powerpc64: Add support for ftrace direct calls Naveen N. Rao
2020-11-26 18:08 ` [RFC PATCH 01/14] ftrace: Fix updating FTRACE_FL_TRAMP Naveen N. Rao
2020-12-01  2:23   ` Steven Rostedt
2020-12-01 13:46     ` Naveen N. Rao
2020-11-26 18:08 ` [RFC PATCH 02/14] ftrace: Fix DYNAMIC_FTRACE_WITH_DIRECT_CALLS dependency Naveen N. Rao
2020-12-01  2:36   ` Steven Rostedt
2020-11-26 18:08 ` [RFC PATCH 03/14] ftrace: Fix cleanup in error path of register_ftrace_direct() Naveen N. Rao
2020-12-01  2:36   ` Steven Rostedt
2020-11-26 18:08 ` [RFC PATCH 04/14] ftrace: Remove ftrace_find_direct_func() Naveen N. Rao
2020-11-26 18:08 ` [RFC PATCH 05/14] ftrace: Add architectural helpers for [un]register_ftrace_direct() Naveen N. Rao
2020-11-26 18:08 ` [RFC PATCH 06/14] powerpc: Add support for CONFIG_HAVE_FUNCTION_ARG_ACCESS_API Naveen N. Rao
2020-11-26 18:08 ` [RFC PATCH 07/14] powerpc/ftrace: Remove dead code Naveen N. Rao
2020-11-26 18:08 ` [RFC PATCH 08/14] powerpc/ftrace: Use FTRACE_REGS_ADDR to identify the correct ftrace trampoline Naveen N. Rao
2020-11-26 18:08 ` [RFC PATCH 09/14] powerpc/ftrace: Use a hash table for tracking ftrace stubs Naveen N. Rao
2020-11-26 18:08 ` [RFC PATCH 10/14] powerpc/ftrace: Drop assumptions about ftrace trampoline target Naveen N. Rao
2020-11-26 18:08 ` [RFC PATCH 11/14] powerpc/ftrace: Use GPR save/restore macros in ftrace_graph_caller() Naveen N. Rao
2020-11-26 18:08 ` Naveen N. Rao [this message]
2020-11-26 18:08 ` [RFC PATCH 13/14] powerpc/ftrace: Add support for register_ftrace_direct() for MPROFILE_KERNEL Naveen N. Rao
2020-11-26 18:08 ` [RFC PATCH 14/14] samples/ftrace: Add powerpc support for ftrace direct samples Naveen N. Rao

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=b40cb303a22f75b85ec0c8d45160e983baff9299.1606412433.git.naveen.n.rao@linux.vnet.ibm.com \
    --to=naveen.n.rao@linux.vnet.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mpe@ellerman.id.au \
    --cc=rostedt@goodmis.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).