From: ndesaulniers@google.com
To: yamada.masahiro@socionext.com
Cc: natechancellor@gmail.com, sedat.dilek@gmail.com,
keescook@chromium.org, samitolvanen@google.com,
michal.lkml@markovi.net, akpm@linux-foundation.org,
hannes@cmpxchg.org, peterz@infradead.org,
linux@dominikbrodowski.net, npiggin@gmail.com,
mathieu.desnoyers@efficios.com, gor@linux.ibm.com,
adrian@lisas.de, rgb@redhat.com, linux-kbuild@vger.kernel.org,
linux-kernel@vger.kernel.org,
Nick Desaulniers <ndesaulniers@google.com>,
Rui Ueyama <ruiu@google.com>
Subject: [PATCH v2 4/4] Makefile: lld: set -O2 linker flag when linking with LLD
Date: Mon, 11 Feb 2019 11:30:06 -0800 [thread overview]
Message-ID: <20190211193008.24101-4-ndesaulniers@google.com> (raw)
In-Reply-To: <20190211193008.24101-1-ndesaulniers@google.com>
For arm64:
0.34% size improvement with lld -O2 over lld for vmlinux.
3.3% size improvement with lld -O2 over lld for Image.lz4-dtb.
Link: https://github.com/ClangBuiltLinux/linux/issues/343
Suggested-by: Rui Ueyama <ruiu@google.com>
Suggested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
---
Changes V1->V2:
* add tested and reviewed by tags.
Makefile | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/Makefile b/Makefile
index 00e8e01d23fc..8011555745aa 100644
--- a/Makefile
+++ b/Makefile
@@ -718,6 +718,10 @@ else
KBUILD_CFLAGS += -Wno-unused-but-set-variable
endif
+ifdef CONFIG_LD_IS_LLD
+KBUILD_LDFLAGS += -O2
+endif
+
KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
ifdef CONFIG_FRAME_POINTER
KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls
--
2.20.1.791.gb4d0f1c61a-goog
next prev parent reply other threads:[~2019-02-11 19:30 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-11 19:30 [PATCH v2 1/4] init/Kconfig: add config support for detecting linker ndesaulniers
2019-02-11 19:30 ` [PATCH v2 2/4] Makefile: clang: choose GCC_TOOLCHAIN_DIR not on LD ndesaulniers
2019-02-16 3:02 ` Masahiro Yamada
2019-02-11 19:30 ` [PATCH v2 3/4] Makefile: lld: tell clang to use lld ndesaulniers
2019-02-13 14:58 ` Masahiro Yamada
2019-02-13 17:41 ` Nick Desaulniers
2019-02-16 3:07 ` Masahiro Yamada
2019-04-02 3:54 ` Nick Desaulniers
2019-04-02 4:49 ` Masahiro Yamada
2019-04-02 7:08 ` [PATCH v3] " Nick Desaulniers
2019-04-02 7:27 ` Nathan Chancellor
2019-04-02 7:33 ` [PATCH v4] " Nick Desaulniers
2019-04-02 7:57 ` Nathan Chancellor
2019-04-02 7:52 ` [PATCH v3] " Sedat Dilek
2019-04-02 7:56 ` Nathan Chancellor
2019-04-05 10:16 ` Masahiro Yamada
2019-04-05 16:11 ` Kees Cook
2019-04-05 16:52 ` Nick Desaulniers
2019-04-07 2:20 ` Masahiro Yamada
2019-02-11 19:30 ` ndesaulniers [this message]
2019-02-12 12:22 ` [PATCH v2 4/4] Makefile: lld: set -O2 linker flag when linking with LLD Peter Zijlstra
2019-02-16 2:55 ` Masahiro Yamada
2019-02-11 19:30 ` [PATCH v2 0/4] Improve kernel LLD support ndesaulniers
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=20190211193008.24101-4-ndesaulniers@google.com \
--to=ndesaulniers@google.com \
--cc=adrian@lisas.de \
--cc=akpm@linux-foundation.org \
--cc=gor@linux.ibm.com \
--cc=hannes@cmpxchg.org \
--cc=keescook@chromium.org \
--cc=linux-kbuild@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@dominikbrodowski.net \
--cc=mathieu.desnoyers@efficios.com \
--cc=michal.lkml@markovi.net \
--cc=natechancellor@gmail.com \
--cc=npiggin@gmail.com \
--cc=peterz@infradead.org \
--cc=rgb@redhat.com \
--cc=ruiu@google.com \
--cc=samitolvanen@google.com \
--cc=sedat.dilek@gmail.com \
--cc=yamada.masahiro@socionext.com \
/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).