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From: Vincenzo Frascino <vincenzo.frascino@arm.com>
To: linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org,
	linux-kselftest@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>, Arnd Bergmann <arnd@arndb.de>,
	Russell King <linux@armlinux.org.uk>,
	Ralf Baechle <ralf@linux-mips.org>,
	Paul Burton <paul.burton@mips.com>,
	Daniel Lezcano <daniel.lezcano@linaro.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Mark Salyzyn <salyzyn@android.com>,
	Peter Collingbourne <pcc@google.com>,
	Shuah Khan <shuah@kernel.org>,
	Dmitry Safonov <0x7f454c46@gmail.com>,
	Rasmus Villemoes <linux@rasmusvillemoes.dk>,
	Huw Davies <huw@codeweavers.com>
Subject: [PATCH v6 03/19] kernel: Unify update_vsyscall implementation
Date: Thu, 30 May 2019 15:15:15 +0100
Message-ID: <20190530141531.43462-4-vincenzo.frascino@arm.com> (raw)
In-Reply-To: <20190530141531.43462-1-vincenzo.frascino@arm.com>

With the definition of the unified vDSO library the implementations of
update_vsyscall and update_vsyscall_tz became quite similar across
architectures.

Define a unified implementation of this two functions in kernel/vdso and
provide the bindings that can be implemented by every architecture that
takes advantage of the unified vDSO library.

Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
---
 include/asm-generic/vdso/vsyscall.h |  56 +++++++++++
 include/linux/timekeeper_internal.h |   9 ++
 include/vdso/vsyscall.h             |  11 +++
 kernel/Makefile                     |   1 +
 kernel/vdso/Makefile                |   2 +
 kernel/vdso/vsyscall.c              | 139 ++++++++++++++++++++++++++++
 6 files changed, 218 insertions(+)
 create mode 100644 include/asm-generic/vdso/vsyscall.h
 create mode 100644 include/vdso/vsyscall.h
 create mode 100644 kernel/vdso/Makefile
 create mode 100644 kernel/vdso/vsyscall.c

diff --git a/include/asm-generic/vdso/vsyscall.h b/include/asm-generic/vdso/vsyscall.h
new file mode 100644
index 000000000000..9a4b9fbcc9b6
--- /dev/null
+++ b/include/asm-generic/vdso/vsyscall.h
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_GENERIC_VSYSCALL_H
+#define __ASM_GENERIC_VSYSCALL_H
+
+#ifndef __ASSEMBLY__
+
+#ifndef __arch_get_k_vdso_data
+static __always_inline
+struct vdso_data *__arch_get_k_vdso_data(void)
+{
+	return NULL;
+}
+#endif /* __arch_get_k_vdso_data */
+
+#ifndef __arch_update_vdso_data
+static __always_inline
+int __arch_update_vdso_data(void)
+{
+	return 0;
+}
+#endif /* __arch_update_vdso_data */
+
+#ifndef __arch_get_clock_mode
+static __always_inline
+int __arch_get_clock_mode(struct timekeeper *tk)
+{
+	return 0;
+}
+#endif /* __arch_get_clock_mode */
+
+#ifndef __arch_use_vsyscall
+static __always_inline
+int __arch_use_vsyscall(struct vdso_data *vdata)
+{
+	return 1;
+}
+#endif /* __arch_use_vsyscall */
+
+#ifndef __arch_update_vsyscall
+static __always_inline
+void __arch_update_vsyscall(struct vdso_data *vdata,
+			    struct timekeeper *tk)
+{
+}
+#endif /* __arch_update_vsyscall */
+
+#ifndef __arch_sync_vdso_data
+static __always_inline
+void __arch_sync_vdso_data(struct vdso_data *vdata)
+{
+}
+#endif /* __arch_sync_vdso_data */
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* __ASM_GENERIC_VSYSCALL_H */
diff --git a/include/linux/timekeeper_internal.h b/include/linux/timekeeper_internal.h
index 7acb953298a7..8177e75a71eb 100644
--- a/include/linux/timekeeper_internal.h
+++ b/include/linux/timekeeper_internal.h
@@ -135,9 +135,18 @@ struct timekeeper {
 
 #ifdef CONFIG_GENERIC_TIME_VSYSCALL
 
+#ifdef CONFIG_HAVE_GENERIC_VDSO
+
+void update_vsyscall(struct timekeeper *tk);
+void update_vsyscall_tz(void);
+
+#else
+
 extern void update_vsyscall(struct timekeeper *tk);
 extern void update_vsyscall_tz(void);
 
+#endif /* CONFIG_HAVE_GENERIC_VDSO */
+
 #else
 
 static inline void update_vsyscall(struct timekeeper *tk)
diff --git a/include/vdso/vsyscall.h b/include/vdso/vsyscall.h
new file mode 100644
index 000000000000..2c6134e0c23d
--- /dev/null
+++ b/include/vdso/vsyscall.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_VSYSCALL_H
+#define __VDSO_VSYSCALL_H
+
+#ifndef __ASSEMBLY__
+
+#include <asm/vdso/vsyscall.h>
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* __VDSO_VSYSCALL_H */
diff --git a/kernel/Makefile b/kernel/Makefile
index 33824f0385b3..56a98ebb7772 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -48,6 +48,7 @@ obj-$(CONFIG_CHECKPOINT_RESTORE) += kcmp.o
 obj-$(CONFIG_FREEZER) += freezer.o
 obj-$(CONFIG_PROFILING) += profile.o
 obj-$(CONFIG_STACKTRACE) += stacktrace.o
+obj-$(CONFIG_HAVE_GENERIC_VDSO) += vdso/
 obj-y += time/
 obj-$(CONFIG_FUTEX) += futex.o
 obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o
diff --git a/kernel/vdso/Makefile b/kernel/vdso/Makefile
new file mode 100644
index 000000000000..ad0d3b1a475c
--- /dev/null
+++ b/kernel/vdso/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_HAVE_GENERIC_VDSO)			+= vsyscall.o
diff --git a/kernel/vdso/vsyscall.c b/kernel/vdso/vsyscall.c
new file mode 100644
index 000000000000..49409eece728
--- /dev/null
+++ b/kernel/vdso/vsyscall.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 ARM Ltd.
+ *
+ * Generic implementation of update_vsyscall and update_vsyscall_tz.
+ */
+
+#include <linux/hrtimer.h>
+#include <linux/timekeeper_internal.h>
+#include <vdso/datapage.h>
+#include <vdso/helpers.h>
+#include <vdso/vsyscall.h>
+
+void update_vsyscall(struct timekeeper *tk)
+{
+	struct vdso_data *vdata = __arch_get_k_vdso_data();
+	struct vdso_timestamp *vdso_ts;
+	u64 nsec;
+
+	if (__arch_update_vdso_data()) {
+		/*
+		 * Some architectures might want to skip the update of the
+		 * data page.
+		 */
+		return;
+	}
+
+	/* copy vsyscall data */
+	vdso_write_begin(vdata);
+
+	vdata[CS_HRES_COARSE].clock_mode	= __arch_get_clock_mode(tk);
+	vdata[CS_RAW].clock_mode		= __arch_get_clock_mode(tk);
+
+	/* CLOCK_REALTIME_COARSE */
+	vdso_ts			=
+			&vdata[CS_HRES_COARSE].basetime[CLOCK_REALTIME_COARSE];
+	vdso_ts->sec		= tk->xtime_sec;
+	vdso_ts->nsec		= tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift;
+	/* CLOCK_MONOTONIC_COARSE */
+	vdso_ts			=
+			&vdata[CS_HRES_COARSE].basetime[CLOCK_MONOTONIC_COARSE];
+	vdso_ts->sec		= tk->xtime_sec + tk->wall_to_monotonic.tv_sec;
+	nsec			= tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift;
+	nsec			= nsec + tk->wall_to_monotonic.tv_nsec;
+	while (nsec >= NSEC_PER_SEC) {
+		nsec = nsec - NSEC_PER_SEC;
+		vdso_ts->sec++;
+	}
+	vdso_ts->nsec		= nsec;
+
+	if (__arch_use_vsyscall(vdata)) {
+		vdata[CS_HRES_COARSE].cycle_last	=
+						tk->tkr_mono.cycle_last;
+		vdata[CS_HRES_COARSE].mask		=
+						tk->tkr_mono.mask;
+		vdata[CS_HRES_COARSE].mult		=
+						tk->tkr_mono.mult;
+		vdata[CS_HRES_COARSE].shift		=
+						tk->tkr_mono.shift;
+		vdata[CS_RAW].cycle_last		=
+						tk->tkr_raw.cycle_last;
+		vdata[CS_RAW].mask			=
+						tk->tkr_raw.mask;
+		vdata[CS_RAW].mult			=
+						tk->tkr_raw.mult;
+		vdata[CS_RAW].shift			=
+						tk->tkr_raw.shift;
+		/* CLOCK_REALTIME */
+		vdso_ts			=
+			&vdata[CS_HRES_COARSE].basetime[CLOCK_REALTIME];
+		vdso_ts->sec		= tk->xtime_sec;
+		vdso_ts->nsec		= tk->tkr_mono.xtime_nsec;
+		/* CLOCK_MONOTONIC */
+		vdso_ts			=
+			&vdata[CS_HRES_COARSE].basetime[CLOCK_MONOTONIC];
+		vdso_ts->sec		= tk->xtime_sec +
+					  tk->wall_to_monotonic.tv_sec;
+		nsec			= tk->tkr_mono.xtime_nsec;
+		nsec			= nsec +
+					  ((u64)tk->wall_to_monotonic.tv_nsec <<
+					  tk->tkr_mono.shift);
+		while (nsec >= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) {
+			nsec = nsec -
+			       (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift);
+			vdso_ts->sec++;
+		}
+		vdso_ts->nsec		= nsec;
+		/* CLOCK_MONOTONIC_RAW */
+		vdso_ts			=
+			&vdata[CS_RAW].basetime[CLOCK_MONOTONIC_RAW];
+		vdso_ts->sec		= tk->raw_sec;
+		vdso_ts->nsec		= tk->tkr_raw.xtime_nsec;
+		/* CLOCK_BOOTTIME */
+		vdso_ts			=
+			&vdata[CS_HRES_COARSE].basetime[CLOCK_BOOTTIME];
+		vdso_ts->sec		= tk->xtime_sec +
+					  tk->wall_to_monotonic.tv_sec;
+		nsec			= tk->tkr_mono.xtime_nsec;
+		nsec			= nsec +
+					  ((u64)(tk->wall_to_monotonic.tv_nsec +
+					  ktime_to_ns(tk->offs_boot)) <<
+					  tk->tkr_mono.shift);
+		while (nsec >= (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) {
+			nsec = nsec -
+				(((u64)NSEC_PER_SEC) << tk->tkr_mono.shift);
+			vdso_ts->sec++;
+		}
+		vdso_ts->nsec		= nsec;
+		/* CLOCK_TAI */
+		vdso_ts			=
+			&vdata[CS_HRES_COARSE].basetime[CLOCK_TAI];
+		vdso_ts->sec		= tk->xtime_sec + (s64)tk->tai_offset;
+		vdso_ts->nsec		= tk->tkr_mono.xtime_nsec;
+
+		/*
+		 * Read without the seqlock held by clock_getres().
+		 * Note: No need to have a second copy.
+		 */
+		WRITE_ONCE(vdata[CS_HRES_COARSE].hrtimer_res, hrtimer_resolution);
+	}
+
+	__arch_update_vsyscall(vdata, tk);
+
+	vdso_write_end(vdata);
+
+	__arch_sync_vdso_data(vdata);
+}
+
+void update_vsyscall_tz(void)
+{
+	struct vdso_data *vdata = __arch_get_k_vdso_data();
+
+	if (__arch_use_vsyscall(vdata)) {
+		vdata[CS_HRES_COARSE].tz_minuteswest = sys_tz.tz_minuteswest;
+		vdata[CS_HRES_COARSE].tz_dsttime = sys_tz.tz_dsttime;
+	}
+
+	__arch_sync_vdso_data(vdata);
+}
-- 
2.21.0


  parent reply index

Thread overview: 69+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-30 14:15 [PATCH v6 00/19] Unify vDSOs across more architectures Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 01/19] kernel: Standardize vdso_datapage Vincenzo Frascino
2019-05-31  8:16   ` Arnd Bergmann
2019-06-04 12:05     ` Vincenzo Frascino
2019-06-10 17:47       ` Huw Davies
2019-06-10  9:27   ` Huw Davies
2019-06-10 10:17     ` Vincenzo Frascino
2019-06-10 10:31       ` Huw Davies
2019-06-10 11:07         ` Vincenzo Frascino
2019-06-10 11:37           ` Huw Davies
2019-05-30 14:15 ` [PATCH v6 02/19] kernel: Define gettimeofday vdso common code Vincenzo Frascino
2019-05-31  8:19   ` Arnd Bergmann
2019-06-04 12:08     ` Vincenzo Frascino
2019-06-10  9:31   ` Huw Davies
2019-06-10 10:18     ` Vincenzo Frascino
2019-05-30 14:15 ` Vincenzo Frascino [this message]
2019-06-10  9:34   ` [PATCH v6 03/19] kernel: Unify update_vsyscall implementation Huw Davies
2019-06-10 10:19     ` Vincenzo Frascino
2019-06-14 11:10   ` Thomas Gleixner
2019-06-14 12:15     ` Vincenzo Frascino
2019-06-14 12:19       ` Thomas Gleixner
2019-06-14 12:25         ` Vincenzo Frascino
2019-06-14 13:07           ` Thomas Gleixner
2019-05-30 14:15 ` [PATCH v6 04/19] arm64: Substitute gettimeofday with C implementation Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 05/19] arm64: Build vDSO with -ffixed-x18 Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 06/19] arm64: compat: Add missing syscall numbers Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 07/19] arm64: compat: Expose signal related structures Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 08/19] arm64: compat: Generate asm offsets for signals Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 09/19] lib: vdso: Add compat support Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 10/19] arm64: compat: Add vDSO Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 11/19] arm64: Refactor vDSO code Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 12/19] arm64: compat: vDSO setup for compat layer Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 13/19] arm64: elf: vDSO code page discovery Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 14/19] arm64: compat: Get sigreturn trampolines from vDSO Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 15/19] arm64: Add vDSO compat support Vincenzo Frascino
2019-06-01  9:38   ` Catalin Marinas
2019-06-04 12:10     ` Vincenzo Frascino
2019-05-30 14:15 ` [PATCH v6 16/19] arm: Add support for generic vDSO Vincenzo Frascino
2019-05-31  8:32   ` Arnd Bergmann
2019-05-30 14:15 ` [PATCH v6 17/19] mips: " Vincenzo Frascino
2019-05-31  8:34   ` Arnd Bergmann
2019-06-03 14:54     ` Mark Salyzyn
2019-06-03 17:07       ` Arnd Bergmann
2019-05-30 14:15 ` [PATCH v6 18/19] x86: " Vincenzo Frascino
2019-05-30 15:41   ` Michael Kelley
2019-06-04 12:13     ` Vincenzo Frascino
2019-06-14 11:15     ` Thomas Gleixner
2019-06-14 21:17       ` Sasha Levin
2019-06-22 14:46         ` Thomas Gleixner
2019-06-23 19:09           ` Sasha Levin
2019-06-23 21:58             ` Stephen Rothwell
2019-06-24  0:24               ` Sasha Levin
2019-06-24  1:20                 ` Stephen Rothwell
2019-06-23 22:12             ` Thomas Gleixner
2019-06-24  0:04               ` Michael Kelley
2019-06-24  0:25                 ` Thomas Gleixner
2019-06-28 18:40                   ` Michael Kelley
2019-05-30 14:15 ` [PATCH v6 19/19] kselftest: Extend vDSO selftest Vincenzo Frascino
2019-05-31  8:53   ` Arnd Bergmann
2019-05-31  8:46 ` [PATCH v6 00/19] Unify vDSOs across more architectures Arnd Bergmann
2019-06-04 12:04   ` Vincenzo Frascino
2019-06-04 12:12     ` Arnd Bergmann
2019-06-05 14:32       ` Vincenzo Frascino
2019-06-14 12:16     ` Thomas Gleixner
2019-06-14 12:19       ` Vincenzo Frascino
2019-06-20  6:17 ` Shijith Thotton
2019-06-20  8:55   ` Vincenzo Frascino
2019-06-20 16:27 ` Andre Przywara
2019-06-21  9:11   ` Vincenzo Frascino

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