From: Evan Green <evan@rivosinc.com>
To: libc-alpha@sourceware.org
Cc: palmer@rivosinc.com, slewis@rivosinc.com, vineetg@rivosinc.com,
Evan Green <evan@rivosinc.com>
Subject: [PATCH v2 2/3] riscv: Add hwprobe vdso call support
Date: Tue, 21 Feb 2023 11:15:36 -0800 [thread overview]
Message-ID: <20230221191537.3159966-3-evan@rivosinc.com> (raw)
In-Reply-To: <20230221191537.3159966-1-evan@rivosinc.com>
The new riscv_hwprobe syscall also comes with a vDSO for faster answers
to your most common questions. Call in today to speak with a kernel
representative near you!
Signed-off-by: Evan Green <evan@rivosinc.com>
---
Changes in v2:
- Add vDSO interface
sysdeps/unix/sysv/linux/dl-vdso-setup.c | 10 ++++++++++
sysdeps/unix/sysv/linux/dl-vdso-setup.h | 3 +++
sysdeps/unix/sysv/linux/riscv/hwprobe.c | 6 ++++++
sysdeps/unix/sysv/linux/riscv/sysdep.h | 1 +
4 files changed, 20 insertions(+)
diff --git a/sysdeps/unix/sysv/linux/dl-vdso-setup.c b/sysdeps/unix/sysv/linux/dl-vdso-setup.c
index 68fa8de641..3fe304a0c7 100644
--- a/sysdeps/unix/sysv/linux/dl-vdso-setup.c
+++ b/sysdeps/unix/sysv/linux/dl-vdso-setup.c
@@ -71,6 +71,16 @@ PROCINFO_CLASS int (*_dl_vdso_clock_getres_time64) (clockid_t,
# ifdef HAVE_GET_TBFREQ
PROCINFO_CLASS uint64_t (*_dl_vdso_get_tbfreq)(void) RELRO;
# endif
+
+/* RISC-V specific ones. */
+# ifdef HAVE_RISCV_HWPROBE
+PROCINFO_CLASS int (*_dl_vdso_riscv_hwprobe)(void *,
+ long,
+ long,
+ unsigned long *,
+ long) RELRO;
+# endif
+
#endif
#undef RELRO
diff --git a/sysdeps/unix/sysv/linux/dl-vdso-setup.h b/sysdeps/unix/sysv/linux/dl-vdso-setup.h
index 867072b897..39eafd5316 100644
--- a/sysdeps/unix/sysv/linux/dl-vdso-setup.h
+++ b/sysdeps/unix/sysv/linux/dl-vdso-setup.h
@@ -47,6 +47,9 @@ setup_vdso_pointers (void)
#ifdef HAVE_GET_TBFREQ
GLRO(dl_vdso_get_tbfreq) = dl_vdso_vsym (HAVE_GET_TBFREQ);
#endif
+#ifdef HAVE_RISCV_HWPROBE
+ GLRO(dl_vdso_riscv_hwprobe) = dl_vdso_vsym (HAVE_RISCV_HWPROBE);
+#endif
}
#endif
diff --git a/sysdeps/unix/sysv/linux/riscv/hwprobe.c b/sysdeps/unix/sysv/linux/riscv/hwprobe.c
index 74f68889ca..2c61a67db7 100644
--- a/sysdeps/unix/sysv/linux/riscv/hwprobe.c
+++ b/sysdeps/unix/sysv/linux/riscv/hwprobe.c
@@ -20,11 +20,17 @@
#include <sys/syscall.h>
#include <sys/hwprobe.h>
#include <sysdep.h>
+#include <sysdep-vdso.h>
int
__riscv_hwprobe (struct riscv_hwprobe *pairs, long pair_count,
long cpu_count, unsigned long *cpus, unsigned long flags)
{
+ /* The vDSO may be able to provide the answer without a syscall. */
+#ifdef HAVE_RISCV_HWPROBE
+ INLINE_VSYSCALL(riscv_hwprobe, 5, pairs, pair_count, cpu_count, cpus, flags);
+#else
return INLINE_SYSCALL_CALL (riscv_hwprobe, pairs, pair_count,
cpu_count, cpus, flags);
+#endif
}
diff --git a/sysdeps/unix/sysv/linux/riscv/sysdep.h b/sysdeps/unix/sysv/linux/riscv/sysdep.h
index 4af5fe5dbc..ba17aaaff2 100644
--- a/sysdeps/unix/sysv/linux/riscv/sysdep.h
+++ b/sysdeps/unix/sysv/linux/riscv/sysdep.h
@@ -155,6 +155,7 @@
/* List of system calls which are supported as vsyscalls (for RV32 and
RV64). */
# define HAVE_GETCPU_VSYSCALL "__vdso_getcpu"
+# define HAVE_RISCV_HWPROBE "__vdso_riscv_hwprobe"
# undef HAVE_INTERNAL_BRK_ADDR_SYMBOL
# define HAVE_INTERNAL_BRK_ADDR_SYMBOL 1
--
2.25.1
next prev parent reply other threads:[~2023-02-21 19:15 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-21 19:15 [PATCH v2 0/3] RISC-V: ifunced memcpy using new kernel hwprobe interface Evan Green
2023-02-21 19:15 ` [PATCH v2 1/3] riscv: Add Linux hwprobe syscall support Evan Green
2023-03-29 18:38 ` Adhemerval Zanella Netto
2023-02-21 19:15 ` Evan Green [this message]
2023-03-29 18:39 ` [PATCH v2 2/3] riscv: Add hwprobe vdso call support Adhemerval Zanella Netto
2023-02-21 19:15 ` [PATCH v2 3/3] riscv: Add and use alignment-ignorant memcpy Evan Green
2023-03-28 22:54 ` [PATCH v2 0/3] RISC-V: ifunced memcpy using new kernel hwprobe interface Palmer Dabbelt
2023-03-28 23:41 ` Adhemerval Zanella Netto
2023-03-29 0:01 ` Palmer Dabbelt
2023-03-29 19:16 ` Adhemerval Zanella Netto
2023-03-29 19:45 ` Palmer Dabbelt
2023-03-29 20:13 ` Adhemerval Zanella Netto
2023-03-30 18:31 ` Evan Green
2023-03-30 19:43 ` Adhemerval Zanella Netto
2023-03-30 6:20 ` Jeff Law
2023-03-30 18:43 ` Evan Green
2023-03-31 5:09 ` Jeff Law
2023-03-30 19:38 ` Adhemerval Zanella Netto
2023-03-31 18:07 ` Jeff Law
2023-03-31 18:34 ` Palmer Dabbelt
2023-03-31 19:32 ` Adhemerval Zanella Netto
2023-03-31 20:19 ` Jeff Law
2023-03-31 21:03 ` Palmer Dabbelt
2023-03-31 21:35 ` Jeff Law
2023-03-31 21:38 ` Palmer Dabbelt
2023-03-31 22:10 ` Jeff Law
2023-04-07 15:36 ` Palmer Dabbelt
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