From: Christoph Muellner <christoph.muellner@vrull.eu>
To: libc-alpha@sourceware.org, Palmer Dabbelt <palmer@dabbelt.com>,
Darius Rad <darius@bluespec.com>,
Andrew Waterman <andrew@sifive.com>, DJ Delorie <dj@redhat.com>,
Vineet Gupta <vineetg@rivosinc.com>,
Kito Cheng <kito.cheng@sifive.com>,
Jeff Law <jeffreyalaw@gmail.com>,
Philipp Tomsich <philipp.tomsich@vrull.eu>,
Heiko Stuebner <heiko.stuebner@vrull.eu>
Cc: "Christoph Müllner" <christoph.muellner@vrull.eu>
Subject: [RFC PATCH 04/19] riscv: Add hart feature run-time detection framework
Date: Tue, 7 Feb 2023 01:16:03 +0100 [thread overview]
Message-ID: <20230207001618.458947-5-christoph.muellner@vrull.eu> (raw)
In-Reply-To: <20230207001618.458947-1-christoph.muellner@vrull.eu>
From: Christoph Müllner <christoph.muellner@vrull.eu>
This patch introduces a framework to detect and store hart features
(e.g. ISA extensions and their parameters) for RISC-V.
This patch does not introduce a concrete mechanism for run-time
detection, but implements everything so that such a mechanism
can be introduced.
Most of the changes in this patch are inspired by similar code
for other architectures, so nothing surprising should be hidden here.
Signed-off-by: Christoph Müllner <christoph.muellner@vrull.eu>
---
sysdeps/riscv/dl-machine.h | 13 ++++
sysdeps/riscv/ldsodefs.h | 1 +
sysdeps/unix/sysv/linux/riscv/dl-procinfo.c | 62 +++++++++++++++++++
sysdeps/unix/sysv/linux/riscv/dl-procinfo.h | 46 ++++++++++++++
sysdeps/unix/sysv/linux/riscv/hart-features.c | 43 +++++++++++++
sysdeps/unix/sysv/linux/riscv/hart-features.h | 26 ++++++++
sysdeps/unix/sysv/linux/riscv/libc-start.c | 29 +++++++++
7 files changed, 220 insertions(+)
create mode 100644 sysdeps/unix/sysv/linux/riscv/dl-procinfo.c
create mode 100644 sysdeps/unix/sysv/linux/riscv/dl-procinfo.h
create mode 100644 sysdeps/unix/sysv/linux/riscv/hart-features.c
create mode 100644 sysdeps/unix/sysv/linux/riscv/hart-features.h
create mode 100644 sysdeps/unix/sysv/linux/riscv/libc-start.c
diff --git a/sysdeps/riscv/dl-machine.h b/sysdeps/riscv/dl-machine.h
index c0c9bd93ad..43f4f96c0e 100644
--- a/sysdeps/riscv/dl-machine.h
+++ b/sysdeps/riscv/dl-machine.h
@@ -28,6 +28,7 @@
#include <dl-irel.h>
#include <dl-static-tls.h>
#include <dl-machine-rel.h>
+#include <hart-features.c>
#ifndef _RTLD_PROLOGUE
# define _RTLD_PROLOGUE(entry) \
@@ -148,6 +149,18 @@ elf_machine_fixup_plt (struct link_map *map, lookup_t t,
return *reloc_addr = value;
}
+#define DL_PLATFORM_INIT dl_platform_init ()
+
+static inline void __attribute__ ((unused))
+dl_platform_init (void)
+{
+#ifdef SHARED
+ /* init_hart_features has been called early from __libc_start_main in
+ static executable. */
+ init_hart_features (&GLRO(dl_riscv_hart_features));
+#endif /* SHARED */
+}
+
#endif /* !dl_machine_h */
#ifdef RESOLVE_MAP
diff --git a/sysdeps/riscv/ldsodefs.h b/sysdeps/riscv/ldsodefs.h
index 90e95e60c5..4b184de255 100644
--- a/sysdeps/riscv/ldsodefs.h
+++ b/sysdeps/riscv/ldsodefs.h
@@ -20,6 +20,7 @@
#define _RISCV_LDSODEFS_H 1
#include <elf.h>
+#include <hart-features.h>
struct La_riscv_regs;
struct La_riscv_retval;
diff --git a/sysdeps/unix/sysv/linux/riscv/dl-procinfo.c b/sysdeps/unix/sysv/linux/riscv/dl-procinfo.c
new file mode 100644
index 0000000000..ce137d10c4
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/riscv/dl-procinfo.c
@@ -0,0 +1,62 @@
+/* Data for RISC-V version of processor capability information.
+ Copyright (C) 2022 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library. If not, see
+ <https://www.gnu.org/licenses/>. */
+
+/* This information must be kept in sync with the _DL_PLATFORM_COUNT
+ definitions in procinfo.h.
+
+ If anything should be added here check whether the size of each string
+ is still ok with the given array size.
+
+ All the #ifdefs in the definitions are quite irritating but
+ necessary if we want to avoid duplicating the information. There
+ are three different modes:
+
+ - PROCINFO_DECL is defined. This means we are only interested in
+ declarations.
+
+ - PROCINFO_DECL is not defined:
+
+ + if SHARED is defined the file is included in an array
+ initializer. The .element = { ... } syntax is needed.
+
+ + if SHARED is not defined a normal array initialization is
+ needed.
+ */
+
+#ifndef PROCINFO_CLASS
+# define PROCINFO_CLASS
+#endif
+
+#if !IS_IN (ldconfig)
+# if !defined PROCINFO_DECL && defined SHARED
+ ._dl_riscv_hart_features
+# else
+PROCINFO_CLASS struct hart_features _dl_riscv_hart_features
+# endif
+# ifndef PROCINFO_DECL
+= { }
+# endif
+# if !defined SHARED || defined PROCINFO_DECL
+;
+# else
+,
+# endif
+#endif
+
+#undef PROCINFO_DECL
+#undef PROCINFO_CLASS
diff --git a/sysdeps/unix/sysv/linux/riscv/dl-procinfo.h b/sysdeps/unix/sysv/linux/riscv/dl-procinfo.h
new file mode 100644
index 0000000000..27aaebe02d
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/riscv/dl-procinfo.h
@@ -0,0 +1,46 @@
+/* RISC-V version of processor capability information handling macros.
+ Copyright (C) 2022 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library. If not, see
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef _DL_PROCINFO_H
+#define _DL_PROCINFO_H 1
+
+#include <sys/auxv.h>
+#include <unistd.h>
+#include <ldsodefs.h>
+#include <sysdep.h>
+
+/* We cannot provide a general printing function. */
+#define _dl_procinfo(word, val) -1
+
+/* There are no hardware capabilities defined. */
+#define _dl_hwcap_string(idx) ""
+
+/* By default there is no important hardware capability. */
+#define HWCAP_IMPORTANT (0)
+
+/* We don't have any hardware capabilities. */
+#define _DL_HWCAP_COUNT 0
+
+#define _dl_string_hwcap(str) (-1)
+
+/* There're no platforms to filter out. */
+#define _DL_HWCAP_PLATFORM 0
+
+#define _dl_string_platform(str) (-1)
+
+#endif /* dl-procinfo.h */
diff --git a/sysdeps/unix/sysv/linux/riscv/hart-features.c b/sysdeps/unix/sysv/linux/riscv/hart-features.c
new file mode 100644
index 0000000000..41111eff57
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/riscv/hart-features.c
@@ -0,0 +1,43 @@
+/* Initialize hart feature data. RISC-V version.
+ This file is part of the GNU C Library.
+ Copyright (C) 2022 Free Software Foundation, Inc.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <hart-features.h>
+
+/* The code in this file is executed very early, so we cannot call
+ indirect functions because ifunc support is not initialized.
+ Therefore this file adds a few simple helper functions to avoid
+ dependencies to functions outside of this file. */
+
+static inline void
+inhibit_loop_to_libcall
+simple_memset (void *s, int c, size_t n)
+{
+ char *p = (char*)s;
+ while (n != 0)
+ {
+ *p = c;
+ n--;
+ }
+}
+
+/* Discover hart features and store them. */
+static inline void
+init_hart_features (struct hart_features *hart_features)
+{
+ simple_memset (hart_features, 0, sizeof (*hart_features));
+}
diff --git a/sysdeps/unix/sysv/linux/riscv/hart-features.h b/sysdeps/unix/sysv/linux/riscv/hart-features.h
new file mode 100644
index 0000000000..a417cbc326
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/riscv/hart-features.h
@@ -0,0 +1,26 @@
+/* Initialize CPU feature data. RISC-V version.
+ This file is part of the GNU C Library.
+ Copyright (C) 2022 Free Software Foundation, Inc.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef _CPU_FEATURES_RISCV_H
+#define _CPU_FEATURES_RISCV_H
+
+struct hart_features
+{
+};
+
+#endif /* _CPU_FEATURES_RISCV_H */
diff --git a/sysdeps/unix/sysv/linux/riscv/libc-start.c b/sysdeps/unix/sysv/linux/riscv/libc-start.c
new file mode 100644
index 0000000000..57c7c09223
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/riscv/libc-start.c
@@ -0,0 +1,29 @@
+/* Override csu/libc-start.c on RISC-V
+ Copyright (C) 2022 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#ifndef SHARED
+
+# include <ldsodefs.h>
+# include <hart-features.c>
+
+extern struct hart_features _dl_riscv_hart_features;
+
+# define ARCH_INIT_CPU_FEATURES() init_hart_features (&_dl_riscv_hart_features)
+
+#endif
+#include <csu/libc-start.c>
--
2.39.1
next prev parent reply other threads:[~2023-02-07 0:16 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-07 0:15 [RFC PATCH 00/19] riscv: ifunc support with optimized mem*/str*/cpu_relax routines Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 01/19] Inhibit early libcalls before ifunc support is ready Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 02/19] riscv: LEAF: Use C_LABEL() to construct the asm name for a C symbol Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 03/19] riscv: Add ENTRY_ALIGN() macro Christoph Muellner
2023-02-07 0:16 ` Christoph Muellner [this message]
2023-02-07 0:16 ` [RFC PATCH 05/19] riscv: Introduction of ISA extensions Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 06/19] riscv: Adding ISA string parser for environment variables Christoph Muellner
2023-02-07 6:20 ` David Abdurachmanov
2023-02-07 0:16 ` [RFC PATCH 07/19] riscv: hart-features: Add fast_unaligned property Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 08/19] riscv: Add (empty) ifunc framework Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 09/19] riscv: Add ifunc support for memset Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 10/19] riscv: Add accelerated memset routines for RV64 Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 11/19] riscv: Add ifunc support for memcpy/memmove Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 12/19] riscv: Add accelerated memcpy/memmove routines for RV64 Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 13/19] riscv: Add ifunc support for strlen Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 14/19] riscv: Add accelerated strlen routine Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 15/19] riscv: Add ifunc support for strcmp Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 16/19] riscv: Add accelerated strcmp routines Christoph Muellner
2023-02-07 11:57 ` Xi Ruoyao
2023-02-07 14:15 ` Christoph Müllner
2023-03-31 5:06 ` Jeff Law
2023-03-31 12:31 ` Adhemerval Zanella Netto
2023-03-31 14:30 ` Jeff Law
2023-03-31 14:48 ` Adhemerval Zanella Netto
2023-03-31 17:19 ` Palmer Dabbelt
2023-03-31 14:32 ` Jeff Law
2023-02-07 0:16 ` [RFC PATCH 17/19] riscv: Add ifunc support for strncmp Christoph Muellner
2023-02-07 0:16 ` [RFC PATCH 18/19] riscv: Add an optimized strncmp routine Christoph Muellner
2023-02-07 1:19 ` Noah Goldstein
2023-02-08 15:13 ` Philipp Tomsich
2023-02-08 17:55 ` Palmer Dabbelt
2023-02-08 19:48 ` Adhemerval Zanella Netto
2023-02-08 18:04 ` Noah Goldstein
2023-02-07 0:16 ` [RFC PATCH 19/19] riscv: Add __riscv_cpu_relax() to allow yielding in busy loops Christoph Muellner
2023-02-07 0:23 ` Andrew Waterman
2023-02-07 0:29 ` Christoph Müllner
2023-02-07 2:59 ` [RFC PATCH 00/19] riscv: ifunc support with optimized mem*/str*/cpu_relax routines Kito Cheng
2023-02-07 16:40 ` Adhemerval Zanella Netto
2023-02-07 17:16 ` DJ Delorie
2023-02-07 19:32 ` Philipp Tomsich
2023-02-07 21:14 ` DJ Delorie
2023-02-08 11:26 ` Christoph Müllner
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=20230207001618.458947-5-christoph.muellner@vrull.eu \
--to=christoph.muellner@vrull.eu \
--cc=andrew@sifive.com \
--cc=darius@bluespec.com \
--cc=dj@redhat.com \
--cc=heiko.stuebner@vrull.eu \
--cc=jeffreyalaw@gmail.com \
--cc=kito.cheng@sifive.com \
--cc=libc-alpha@sourceware.org \
--cc=palmer@dabbelt.com \
--cc=philipp.tomsich@vrull.eu \
--cc=vineetg@rivosinc.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 read-only IMAP folder(s) and NNTP newsgroup(s).