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* [PATCH v9 0/5] powerpc: switch VDSO to C implementation
@ 2020-08-04 11:47 Christophe Leroy
  2020-08-04 11:47 ` [PATCH v9 1/5] powerpc/processor: Move cpu_relax() into asm/vdso/processor.h Christophe Leroy
                   ` (4 more replies)
  0 siblings, 5 replies; 10+ messages in thread
From: Christophe Leroy @ 2020-08-04 11:47 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl, anton
  Cc: linux-kernel, linuxppc-dev, arnd, tglx, vincenzo.frascino, luto,
	linux-arch

This is the nineth version of a series to switch powerpc VDSO to
generic C implementation.

Main changes since v8 are:
- Dropped the patches which put the VDSO datapage in front of VDSO text in the mapping
- Adds a second stack frame because the caller doesn't set one, at least on PPC64
- Saving the TOC pointer on PPC64 (is that really needed ?)

This series applies on today's powerpc/merge branch.

See the last patches for details on changes and performance.

Christophe Leroy (5):
  powerpc/processor: Move cpu_relax() into asm/vdso/processor.h
  powerpc/vdso: Prepare for switching VDSO to generic C implementation.
  powerpc/vdso: Save and restore TOC pointer on PPC64
  powerpc/vdso: Switch VDSO to generic C implementation.
  powerpc/vdso: Provide __kernel_clock_gettime64() on vdso32

 arch/powerpc/Kconfig                         |   2 +
 arch/powerpc/include/asm/clocksource.h       |   7 +
 arch/powerpc/include/asm/processor.h         |  13 +-
 arch/powerpc/include/asm/vdso/clocksource.h  |   7 +
 arch/powerpc/include/asm/vdso/gettimeofday.h | 191 ++++++++++++
 arch/powerpc/include/asm/vdso/processor.h    |  23 ++
 arch/powerpc/include/asm/vdso/vsyscall.h     |  25 ++
 arch/powerpc/include/asm/vdso_datapage.h     |  40 +--
 arch/powerpc/kernel/asm-offsets.c            |  49 +--
 arch/powerpc/kernel/time.c                   |  91 +-----
 arch/powerpc/kernel/vdso.c                   |   5 +-
 arch/powerpc/kernel/vdso32/Makefile          |  32 +-
 arch/powerpc/kernel/vdso32/config-fake32.h   |  34 +++
 arch/powerpc/kernel/vdso32/gettimeofday.S    | 300 +------------------
 arch/powerpc/kernel/vdso32/vdso32.lds.S      |   1 +
 arch/powerpc/kernel/vdso32/vgettimeofday.c   |  35 +++
 arch/powerpc/kernel/vdso64/Makefile          |  23 +-
 arch/powerpc/kernel/vdso64/gettimeofday.S    | 242 +--------------
 arch/powerpc/kernel/vdso64/vgettimeofday.c   |  29 ++
 19 files changed, 447 insertions(+), 702 deletions(-)
 create mode 100644 arch/powerpc/include/asm/clocksource.h
 create mode 100644 arch/powerpc/include/asm/vdso/clocksource.h
 create mode 100644 arch/powerpc/include/asm/vdso/gettimeofday.h
 create mode 100644 arch/powerpc/include/asm/vdso/processor.h
 create mode 100644 arch/powerpc/include/asm/vdso/vsyscall.h
 create mode 100644 arch/powerpc/kernel/vdso32/config-fake32.h
 create mode 100644 arch/powerpc/kernel/vdso32/vgettimeofday.c
 create mode 100644 arch/powerpc/kernel/vdso64/vgettimeofday.c

-- 
2.25.0

^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH v9 1/5] powerpc/processor: Move cpu_relax() into asm/vdso/processor.h
  2020-08-04 11:47 [PATCH v9 0/5] powerpc: switch VDSO to C implementation Christophe Leroy
@ 2020-08-04 11:47 ` Christophe Leroy
  2020-08-04 11:47   ` Christophe Leroy
  2020-08-04 11:47 ` [PATCH v9 2/5] powerpc/vdso: Prepare for switching VDSO to generic C implementation Christophe Leroy
                   ` (3 subsequent siblings)
  4 siblings, 1 reply; 10+ messages in thread
From: Christophe Leroy @ 2020-08-04 11:47 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl, anton
  Cc: linux-arch, arnd, linux-kernel, luto, tglx, vincenzo.frascino,
	linuxppc-dev

cpu_relax() need to be in asm/vdso/processor.h to be used by
the C VDSO generic library.

Move it there.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v9: Forgot to remove cpu_relax() from processor.h in v8
---
 arch/powerpc/include/asm/processor.h      | 13 ++-----------
 arch/powerpc/include/asm/vdso/processor.h | 23 +++++++++++++++++++++++
 2 files changed, 25 insertions(+), 11 deletions(-)
 create mode 100644 arch/powerpc/include/asm/vdso/processor.h

diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index ed0d633ab5aa..c1ba9c8d9b90 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -6,6 +6,8 @@
  * Copyright (C) 2001 PPC 64 Team, IBM Corp
  */
 
+#include <vdso/processor.h>
+
 #include <asm/reg.h>
 
 #ifdef CONFIG_VSX
@@ -63,14 +65,6 @@ extern int _chrp_type;
 
 #endif /* defined(__KERNEL__) && defined(CONFIG_PPC32) */
 
-/* Macros for adjusting thread priority (hardware multi-threading) */
-#define HMT_very_low()   asm volatile("or 31,31,31   # very low priority")
-#define HMT_low()	 asm volatile("or 1,1,1	     # low priority")
-#define HMT_medium_low() asm volatile("or 6,6,6      # medium low priority")
-#define HMT_medium()	 asm volatile("or 2,2,2	     # medium priority")
-#define HMT_medium_high() asm volatile("or 5,5,5      # medium high priority")
-#define HMT_high()	 asm volatile("or 3,3,3	     # high priority")
-
 #ifdef __KERNEL__
 
 #ifdef CONFIG_PPC64
@@ -350,7 +344,6 @@ static inline unsigned long __pack_fe01(unsigned int fpmode)
 }
 
 #ifdef CONFIG_PPC64
-#define cpu_relax()	do { HMT_low(); HMT_medium(); barrier(); } while (0)
 
 #define spin_begin()	HMT_low()
 
@@ -369,8 +362,6 @@ do {								\
 	}							\
 } while (0)
 
-#else
-#define cpu_relax()	barrier()
 #endif
 
 /* Check that a certain kernel stack pointer is valid in task_struct p */
diff --git a/arch/powerpc/include/asm/vdso/processor.h b/arch/powerpc/include/asm/vdso/processor.h
new file mode 100644
index 000000000000..39b9beace9ca
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/processor.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __ASM_VDSO_PROCESSOR_H
+#define __ASM_VDSO_PROCESSOR_H
+
+#ifndef __ASSEMBLY__
+
+/* Macros for adjusting thread priority (hardware multi-threading) */
+#define HMT_very_low()		asm volatile("or 31, 31, 31	# very low priority")
+#define HMT_low()		asm volatile("or 1, 1, 1	# low priority")
+#define HMT_medium_low()	asm volatile("or 6, 6, 6	# medium low priority")
+#define HMT_medium()		asm volatile("or 2, 2, 2	# medium priority")
+#define HMT_medium_high()	asm volatile("or 5, 5, 5	# medium high priority")
+#define HMT_high()		asm volatile("or 3, 3, 3	# high priority")
+
+#ifdef CONFIG_PPC64
+#define cpu_relax()	do { HMT_low(); HMT_medium(); barrier(); } while (0)
+#else
+#define cpu_relax()	barrier()
+#endif
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_VDSO_PROCESSOR_H */
-- 
2.25.0

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v9 1/5] powerpc/processor: Move cpu_relax() into asm/vdso/processor.h
  2020-08-04 11:47 ` [PATCH v9 1/5] powerpc/processor: Move cpu_relax() into asm/vdso/processor.h Christophe Leroy
@ 2020-08-04 11:47   ` Christophe Leroy
  0 siblings, 0 replies; 10+ messages in thread
From: Christophe Leroy @ 2020-08-04 11:47 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl, anton
  Cc: linux-kernel, linuxppc-dev, arnd, tglx, vincenzo.frascino, luto,
	linux-arch

cpu_relax() need to be in asm/vdso/processor.h to be used by
the C VDSO generic library.

Move it there.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v9: Forgot to remove cpu_relax() from processor.h in v8
---
 arch/powerpc/include/asm/processor.h      | 13 ++-----------
 arch/powerpc/include/asm/vdso/processor.h | 23 +++++++++++++++++++++++
 2 files changed, 25 insertions(+), 11 deletions(-)
 create mode 100644 arch/powerpc/include/asm/vdso/processor.h

diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index ed0d633ab5aa..c1ba9c8d9b90 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -6,6 +6,8 @@
  * Copyright (C) 2001 PPC 64 Team, IBM Corp
  */
 
+#include <vdso/processor.h>
+
 #include <asm/reg.h>
 
 #ifdef CONFIG_VSX
@@ -63,14 +65,6 @@ extern int _chrp_type;
 
 #endif /* defined(__KERNEL__) && defined(CONFIG_PPC32) */
 
-/* Macros for adjusting thread priority (hardware multi-threading) */
-#define HMT_very_low()   asm volatile("or 31,31,31   # very low priority")
-#define HMT_low()	 asm volatile("or 1,1,1	     # low priority")
-#define HMT_medium_low() asm volatile("or 6,6,6      # medium low priority")
-#define HMT_medium()	 asm volatile("or 2,2,2	     # medium priority")
-#define HMT_medium_high() asm volatile("or 5,5,5      # medium high priority")
-#define HMT_high()	 asm volatile("or 3,3,3	     # high priority")
-
 #ifdef __KERNEL__
 
 #ifdef CONFIG_PPC64
@@ -350,7 +344,6 @@ static inline unsigned long __pack_fe01(unsigned int fpmode)
 }
 
 #ifdef CONFIG_PPC64
-#define cpu_relax()	do { HMT_low(); HMT_medium(); barrier(); } while (0)
 
 #define spin_begin()	HMT_low()
 
@@ -369,8 +362,6 @@ do {								\
 	}							\
 } while (0)
 
-#else
-#define cpu_relax()	barrier()
 #endif
 
 /* Check that a certain kernel stack pointer is valid in task_struct p */
diff --git a/arch/powerpc/include/asm/vdso/processor.h b/arch/powerpc/include/asm/vdso/processor.h
new file mode 100644
index 000000000000..39b9beace9ca
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/processor.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __ASM_VDSO_PROCESSOR_H
+#define __ASM_VDSO_PROCESSOR_H
+
+#ifndef __ASSEMBLY__
+
+/* Macros for adjusting thread priority (hardware multi-threading) */
+#define HMT_very_low()		asm volatile("or 31, 31, 31	# very low priority")
+#define HMT_low()		asm volatile("or 1, 1, 1	# low priority")
+#define HMT_medium_low()	asm volatile("or 6, 6, 6	# medium low priority")
+#define HMT_medium()		asm volatile("or 2, 2, 2	# medium priority")
+#define HMT_medium_high()	asm volatile("or 5, 5, 5	# medium high priority")
+#define HMT_high()		asm volatile("or 3, 3, 3	# high priority")
+
+#ifdef CONFIG_PPC64
+#define cpu_relax()	do { HMT_low(); HMT_medium(); barrier(); } while (0)
+#else
+#define cpu_relax()	barrier()
+#endif
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_VDSO_PROCESSOR_H */
-- 
2.25.0

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v9 2/5] powerpc/vdso: Prepare for switching VDSO to generic C implementation.
  2020-08-04 11:47 [PATCH v9 0/5] powerpc: switch VDSO to C implementation Christophe Leroy
  2020-08-04 11:47 ` [PATCH v9 1/5] powerpc/processor: Move cpu_relax() into asm/vdso/processor.h Christophe Leroy
@ 2020-08-04 11:47 ` Christophe Leroy
  2020-08-04 11:47   ` Christophe Leroy
  2020-08-04 11:47 ` [PATCH v9 3/5] powerpc/vdso: Save and restore TOC pointer on PPC64 Christophe Leroy
                   ` (2 subsequent siblings)
  4 siblings, 1 reply; 10+ messages in thread
From: Christophe Leroy @ 2020-08-04 11:47 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl, anton
  Cc: linux-kernel, linuxppc-dev, arnd, tglx, vincenzo.frascino, luto,
	linux-arch

Prepare for switching VDSO to generic C implementation in following
patch. Here, we:
- Prepare the helpers to call the C VDSO functions
- Prepare the required callbacks for the C VDSO functions
- Prepare the clocksource.h files to define VDSO_ARCH_CLOCKMODES
- Add the C trampolines to the generic C VDSO functions

powerpc is a bit special for VDSO as well as system calls in the
way that it requires setting CR SO bit which cannot be done in C.
Therefore, entry/exit needs to be performed in ASM.

Implementing __arch_get_vdso_data() would clobber the link register,
requiring the caller to save it. As the ASM calling function already
has to set a stack frame and saves the link register before calling
the C vdso function, retriving the vdso data pointer there is lighter.

Implement __arch_vdso_capable() and:
- When the timebase is used, make it always return true.
- When the RTC clock is used, make it always return false.

Provide vdso_shift_ns(), as the generic x >> s gives the following
bad result:

  18:	35 25 ff e0 	addic.  r9,r5,-32
  1c:	41 80 00 10 	blt     2c <shift+0x14>
  20:	7c 64 4c 30 	srw     r4,r3,r9
  24:	38 60 00 00 	li      r3,0
...
  2c:	54 69 08 3c 	rlwinm  r9,r3,1,0,30
  30:	21 45 00 1f 	subfic  r10,r5,31
  34:	7c 84 2c 30 	srw     r4,r4,r5
  38:	7d 29 50 30 	slw     r9,r9,r10
  3c:	7c 63 2c 30 	srw     r3,r3,r5
  40:	7d 24 23 78 	or      r4,r9,r4

In our case the shift is always <= 32. In addition,  the upper 32 bits
of the result are likely nul. Lets GCC know it, it also optimises the
following calculations.

With the patch, we get:
   0:	21 25 00 20 	subfic  r9,r5,32
   4:	7c 69 48 30 	slw     r9,r3,r9
   8:	7c 84 2c 30 	srw     r4,r4,r5
   c:	7d 24 23 78 	or      r4,r9,r4
  10:	7c 63 2c 30 	srw     r3,r3,r5

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v9:
- No more modification of __get_datapage(). Offset is added after.
- Adding a second stack frame because the PPC VDSO ABI doesn't force
the caller to set one.

v8:
- New, splitted out of last patch of the series

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/include/asm/clocksource.h       |   7 +
 arch/powerpc/include/asm/vdso/clocksource.h  |   7 +
 arch/powerpc/include/asm/vdso/gettimeofday.h | 179 +++++++++++++++++++
 arch/powerpc/kernel/vdso32/vgettimeofday.c   |  29 +++
 arch/powerpc/kernel/vdso64/vgettimeofday.c   |  29 +++
 5 files changed, 251 insertions(+)
 create mode 100644 arch/powerpc/include/asm/clocksource.h
 create mode 100644 arch/powerpc/include/asm/vdso/clocksource.h
 create mode 100644 arch/powerpc/include/asm/vdso/gettimeofday.h
 create mode 100644 arch/powerpc/kernel/vdso32/vgettimeofday.c
 create mode 100644 arch/powerpc/kernel/vdso64/vgettimeofday.c

diff --git a/arch/powerpc/include/asm/clocksource.h b/arch/powerpc/include/asm/clocksource.h
new file mode 100644
index 000000000000..482185566b0c
--- /dev/null
+++ b/arch/powerpc/include/asm/clocksource.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_CLOCKSOURCE_H
+#define _ASM_CLOCKSOURCE_H
+
+#include <asm/vdso/clocksource.h>
+
+#endif
diff --git a/arch/powerpc/include/asm/vdso/clocksource.h b/arch/powerpc/include/asm/vdso/clocksource.h
new file mode 100644
index 000000000000..ec5d672d2569
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/clocksource.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_VDSOCLOCKSOURCE_H
+#define __ASM_VDSOCLOCKSOURCE_H
+
+#define VDSO_ARCH_CLOCKMODES	VDSO_CLOCKMODE_ARCHTIMER
+
+#endif
diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
new file mode 100644
index 000000000000..0b6fa245d54e
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
@@ -0,0 +1,179 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_VDSO_GETTIMEOFDAY_H
+#define __ASM_VDSO_GETTIMEOFDAY_H
+
+#include <asm/ptrace.h>
+
+#ifdef __ASSEMBLY__
+
+.macro cvdso_call funct
+  .cfi_startproc
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+	mflr		r0
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+  .cfi_register lr, r0
+	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	get_datapage	r5, r0
+	addi		r5, r5, VDSO_DATA_OFFSET
+	bl		\funct
+	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	cmpwi		r3, 0
+	mtlr		r0
+  .cfi_restore lr
+	addi		r1, r1, 2 * STACK_FRAME_OVERHEAD
+	crclr		so
+	beqlr+
+	crset		so
+	neg		r3, r3
+	blr
+  .cfi_endproc
+.endm
+
+.macro cvdso_call_time funct
+  .cfi_startproc
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+	mflr		r0
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+  .cfi_register lr, r0
+	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	get_datapage	r4, r0
+	addi		r4, r4, VDSO_DATA_OFFSET
+	bl		\funct
+	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	crclr		so
+	mtlr		r0
+  .cfi_restore lr
+	addi		r1, r1, 2 * STACK_FRAME_OVERHEAD
+	blr
+  .cfi_endproc
+.endm
+
+#else
+
+#include <asm/time.h>
+#include <asm/unistd.h>
+#include <uapi/linux/time.h>
+
+#define VDSO_HAS_CLOCK_GETRES		1
+
+#define VDSO_HAS_TIME			1
+
+static __always_inline int do_syscall_2(const unsigned long _r0, const unsigned long _r3,
+					const unsigned long _r4)
+{
+	register long r0 asm("r0") = _r0;
+	register unsigned long r3 asm("r3") = _r3;
+	register unsigned long r4 asm("r4") = _r4;
+	register int ret asm ("r3");
+
+	asm volatile(
+		"       sc\n"
+		"	bns+	1f\n"
+		"	neg	%0, %0\n"
+		"1:\n"
+	: "=r" (ret), "+r" (r4), "+r" (r0)
+	: "r" (r3)
+	: "memory", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "cr0", "ctr");
+
+	return ret;
+}
+
+static __always_inline
+int gettimeofday_fallback(struct __kernel_old_timeval *_tv, struct timezone *_tz)
+{
+	return do_syscall_2(__NR_gettimeofday, (unsigned long)_tv, (unsigned long)_tz);
+}
+
+static __always_inline
+int clock_gettime_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
+{
+	return do_syscall_2(__NR_clock_gettime, _clkid, (unsigned long)_ts);
+}
+
+static __always_inline
+int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
+{
+	return do_syscall_2(__NR_clock_getres, _clkid, (unsigned long)_ts);
+}
+
+#ifdef CONFIG_VDSO32
+
+#define BUILD_VDSO32		1
+
+static __always_inline
+int clock_gettime32_fallback(clockid_t _clkid, struct old_timespec32 *_ts)
+{
+	return do_syscall_2(__NR_clock_gettime, _clkid, (unsigned long)_ts);
+}
+
+static __always_inline
+int clock_getres32_fallback(clockid_t _clkid, struct old_timespec32 *_ts)
+{
+	return do_syscall_2(__NR_clock_getres, _clkid, (unsigned long)_ts);
+}
+#endif
+
+static __always_inline u64 __arch_get_hw_counter(s32 clock_mode)
+{
+	return get_tb();
+}
+
+const struct vdso_data *__arch_get_vdso_data(void);
+
+static inline bool vdso_clocksource_ok(const struct vdso_data *vd)
+{
+	return !__USE_RTC();
+}
+#define vdso_clocksource_ok vdso_clocksource_ok
+
+/*
+ * powerpc specific delta calculation.
+ *
+ * This variant removes the masking of the subtraction because the
+ * clocksource mask of all VDSO capable clocksources on powerpc is U64_MAX
+ * which would result in a pointless operation. The compiler cannot
+ * optimize it away as the mask comes from the vdso data and is not compile
+ * time constant.
+ */
+static __always_inline u64 vdso_calc_delta(u64 cycles, u64 last, u64 mask, u32 mult)
+{
+	return (cycles - last) * mult;
+}
+#define vdso_calc_delta vdso_calc_delta
+
+#ifndef __powerpc64__
+static __always_inline u64 vdso_shift_ns(u64 ns, unsigned long shift)
+{
+	u32 hi = ns >> 32;
+	u32 lo = ns;
+
+	lo >>= shift;
+	lo |= hi << (32 - shift);
+	hi >>= shift;
+
+	if (likely(hi == 0))
+		return lo;
+
+	return ((u64)hi << 32) | lo;
+}
+#define vdso_shift_ns vdso_shift_ns
+#endif
+
+#ifdef __powerpc64__
+int __c_kernel_clock_gettime(clockid_t clock, struct __kernel_timespec *ts,
+			     const struct vdso_data *vd);
+int __c_kernel_clock_getres(clockid_t clock_id, struct __kernel_timespec *res,
+			    const struct vdso_data *vd);
+#else
+int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
+			     const struct vdso_data *vd);
+int __c_kernel_clock_getres(clockid_t clock_id, struct old_timespec32 *res,
+			    const struct vdso_data *vd);
+#endif
+int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
+			    const struct vdso_data *vd);
+__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time,
+				    const struct vdso_data *vd);
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_VDSO_GETTIMEOFDAY_H */
diff --git a/arch/powerpc/kernel/vdso32/vgettimeofday.c b/arch/powerpc/kernel/vdso32/vgettimeofday.c
new file mode 100644
index 000000000000..0b9ab4c22ef2
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/vgettimeofday.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Powerpc userspace implementations of gettimeofday() and similar.
+ */
+#include <linux/time.h>
+#include <linux/types.h>
+
+int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
+			     const struct vdso_data *vd)
+{
+	return __cvdso_clock_gettime32_data(vd, clock, ts);
+}
+
+int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_gettimeofday_data(vd, tv, tz);
+}
+
+int __c_kernel_clock_getres(clockid_t clock_id, struct old_timespec32 *res,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_clock_getres_time32_data(vd, clock_id, res);
+}
+
+__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time, const struct vdso_data *vd)
+{
+	return __cvdso_time_data(vd, time);
+}
diff --git a/arch/powerpc/kernel/vdso64/vgettimeofday.c b/arch/powerpc/kernel/vdso64/vgettimeofday.c
new file mode 100644
index 000000000000..5b5500058344
--- /dev/null
+++ b/arch/powerpc/kernel/vdso64/vgettimeofday.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Powerpc userspace implementations of gettimeofday() and similar.
+ */
+#include <linux/time.h>
+#include <linux/types.h>
+
+int __c_kernel_clock_gettime(clockid_t clock, struct __kernel_timespec *ts,
+			     const struct vdso_data *vd)
+{
+	return __cvdso_clock_gettime_data(vd, clock, ts);
+}
+
+int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_gettimeofday_data(vd, tv, tz);
+}
+
+int __c_kernel_clock_getres(clockid_t clock_id, struct __kernel_timespec *res,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_clock_getres_data(vd, clock_id, res);
+}
+
+__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time, const struct vdso_data *vd)
+{
+	return __cvdso_time_data(vd, time);
+}
-- 
2.25.0

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v9 2/5] powerpc/vdso: Prepare for switching VDSO to generic C implementation.
  2020-08-04 11:47 ` [PATCH v9 2/5] powerpc/vdso: Prepare for switching VDSO to generic C implementation Christophe Leroy
@ 2020-08-04 11:47   ` Christophe Leroy
  0 siblings, 0 replies; 10+ messages in thread
From: Christophe Leroy @ 2020-08-04 11:47 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl, anton
  Cc: linux-kernel, linuxppc-dev, arnd, tglx, vincenzo.frascino, luto,
	linux-arch

Prepare for switching VDSO to generic C implementation in following
patch. Here, we:
- Prepare the helpers to call the C VDSO functions
- Prepare the required callbacks for the C VDSO functions
- Prepare the clocksource.h files to define VDSO_ARCH_CLOCKMODES
- Add the C trampolines to the generic C VDSO functions

powerpc is a bit special for VDSO as well as system calls in the
way that it requires setting CR SO bit which cannot be done in C.
Therefore, entry/exit needs to be performed in ASM.

Implementing __arch_get_vdso_data() would clobber the link register,
requiring the caller to save it. As the ASM calling function already
has to set a stack frame and saves the link register before calling
the C vdso function, retriving the vdso data pointer there is lighter.

Implement __arch_vdso_capable() and:
- When the timebase is used, make it always return true.
- When the RTC clock is used, make it always return false.

Provide vdso_shift_ns(), as the generic x >> s gives the following
bad result:

  18:	35 25 ff e0 	addic.  r9,r5,-32
  1c:	41 80 00 10 	blt     2c <shift+0x14>
  20:	7c 64 4c 30 	srw     r4,r3,r9
  24:	38 60 00 00 	li      r3,0
...
  2c:	54 69 08 3c 	rlwinm  r9,r3,1,0,30
  30:	21 45 00 1f 	subfic  r10,r5,31
  34:	7c 84 2c 30 	srw     r4,r4,r5
  38:	7d 29 50 30 	slw     r9,r9,r10
  3c:	7c 63 2c 30 	srw     r3,r3,r5
  40:	7d 24 23 78 	or      r4,r9,r4

In our case the shift is always <= 32. In addition,  the upper 32 bits
of the result are likely nul. Lets GCC know it, it also optimises the
following calculations.

With the patch, we get:
   0:	21 25 00 20 	subfic  r9,r5,32
   4:	7c 69 48 30 	slw     r9,r3,r9
   8:	7c 84 2c 30 	srw     r4,r4,r5
   c:	7d 24 23 78 	or      r4,r9,r4
  10:	7c 63 2c 30 	srw     r3,r3,r5

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v9:
- No more modification of __get_datapage(). Offset is added after.
- Adding a second stack frame because the PPC VDSO ABI doesn't force
the caller to set one.

v8:
- New, splitted out of last patch of the series

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/include/asm/clocksource.h       |   7 +
 arch/powerpc/include/asm/vdso/clocksource.h  |   7 +
 arch/powerpc/include/asm/vdso/gettimeofday.h | 179 +++++++++++++++++++
 arch/powerpc/kernel/vdso32/vgettimeofday.c   |  29 +++
 arch/powerpc/kernel/vdso64/vgettimeofday.c   |  29 +++
 5 files changed, 251 insertions(+)
 create mode 100644 arch/powerpc/include/asm/clocksource.h
 create mode 100644 arch/powerpc/include/asm/vdso/clocksource.h
 create mode 100644 arch/powerpc/include/asm/vdso/gettimeofday.h
 create mode 100644 arch/powerpc/kernel/vdso32/vgettimeofday.c
 create mode 100644 arch/powerpc/kernel/vdso64/vgettimeofday.c

diff --git a/arch/powerpc/include/asm/clocksource.h b/arch/powerpc/include/asm/clocksource.h
new file mode 100644
index 000000000000..482185566b0c
--- /dev/null
+++ b/arch/powerpc/include/asm/clocksource.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_CLOCKSOURCE_H
+#define _ASM_CLOCKSOURCE_H
+
+#include <asm/vdso/clocksource.h>
+
+#endif
diff --git a/arch/powerpc/include/asm/vdso/clocksource.h b/arch/powerpc/include/asm/vdso/clocksource.h
new file mode 100644
index 000000000000..ec5d672d2569
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/clocksource.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_VDSOCLOCKSOURCE_H
+#define __ASM_VDSOCLOCKSOURCE_H
+
+#define VDSO_ARCH_CLOCKMODES	VDSO_CLOCKMODE_ARCHTIMER
+
+#endif
diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
new file mode 100644
index 000000000000..0b6fa245d54e
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
@@ -0,0 +1,179 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_VDSO_GETTIMEOFDAY_H
+#define __ASM_VDSO_GETTIMEOFDAY_H
+
+#include <asm/ptrace.h>
+
+#ifdef __ASSEMBLY__
+
+.macro cvdso_call funct
+  .cfi_startproc
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+	mflr		r0
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+  .cfi_register lr, r0
+	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	get_datapage	r5, r0
+	addi		r5, r5, VDSO_DATA_OFFSET
+	bl		\funct
+	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	cmpwi		r3, 0
+	mtlr		r0
+  .cfi_restore lr
+	addi		r1, r1, 2 * STACK_FRAME_OVERHEAD
+	crclr		so
+	beqlr+
+	crset		so
+	neg		r3, r3
+	blr
+  .cfi_endproc
+.endm
+
+.macro cvdso_call_time funct
+  .cfi_startproc
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+	mflr		r0
+	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
+  .cfi_register lr, r0
+	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	get_datapage	r4, r0
+	addi		r4, r4, VDSO_DATA_OFFSET
+	bl		\funct
+	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+	crclr		so
+	mtlr		r0
+  .cfi_restore lr
+	addi		r1, r1, 2 * STACK_FRAME_OVERHEAD
+	blr
+  .cfi_endproc
+.endm
+
+#else
+
+#include <asm/time.h>
+#include <asm/unistd.h>
+#include <uapi/linux/time.h>
+
+#define VDSO_HAS_CLOCK_GETRES		1
+
+#define VDSO_HAS_TIME			1
+
+static __always_inline int do_syscall_2(const unsigned long _r0, const unsigned long _r3,
+					const unsigned long _r4)
+{
+	register long r0 asm("r0") = _r0;
+	register unsigned long r3 asm("r3") = _r3;
+	register unsigned long r4 asm("r4") = _r4;
+	register int ret asm ("r3");
+
+	asm volatile(
+		"       sc\n"
+		"	bns+	1f\n"
+		"	neg	%0, %0\n"
+		"1:\n"
+	: "=r" (ret), "+r" (r4), "+r" (r0)
+	: "r" (r3)
+	: "memory", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "cr0", "ctr");
+
+	return ret;
+}
+
+static __always_inline
+int gettimeofday_fallback(struct __kernel_old_timeval *_tv, struct timezone *_tz)
+{
+	return do_syscall_2(__NR_gettimeofday, (unsigned long)_tv, (unsigned long)_tz);
+}
+
+static __always_inline
+int clock_gettime_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
+{
+	return do_syscall_2(__NR_clock_gettime, _clkid, (unsigned long)_ts);
+}
+
+static __always_inline
+int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts)
+{
+	return do_syscall_2(__NR_clock_getres, _clkid, (unsigned long)_ts);
+}
+
+#ifdef CONFIG_VDSO32
+
+#define BUILD_VDSO32		1
+
+static __always_inline
+int clock_gettime32_fallback(clockid_t _clkid, struct old_timespec32 *_ts)
+{
+	return do_syscall_2(__NR_clock_gettime, _clkid, (unsigned long)_ts);
+}
+
+static __always_inline
+int clock_getres32_fallback(clockid_t _clkid, struct old_timespec32 *_ts)
+{
+	return do_syscall_2(__NR_clock_getres, _clkid, (unsigned long)_ts);
+}
+#endif
+
+static __always_inline u64 __arch_get_hw_counter(s32 clock_mode)
+{
+	return get_tb();
+}
+
+const struct vdso_data *__arch_get_vdso_data(void);
+
+static inline bool vdso_clocksource_ok(const struct vdso_data *vd)
+{
+	return !__USE_RTC();
+}
+#define vdso_clocksource_ok vdso_clocksource_ok
+
+/*
+ * powerpc specific delta calculation.
+ *
+ * This variant removes the masking of the subtraction because the
+ * clocksource mask of all VDSO capable clocksources on powerpc is U64_MAX
+ * which would result in a pointless operation. The compiler cannot
+ * optimize it away as the mask comes from the vdso data and is not compile
+ * time constant.
+ */
+static __always_inline u64 vdso_calc_delta(u64 cycles, u64 last, u64 mask, u32 mult)
+{
+	return (cycles - last) * mult;
+}
+#define vdso_calc_delta vdso_calc_delta
+
+#ifndef __powerpc64__
+static __always_inline u64 vdso_shift_ns(u64 ns, unsigned long shift)
+{
+	u32 hi = ns >> 32;
+	u32 lo = ns;
+
+	lo >>= shift;
+	lo |= hi << (32 - shift);
+	hi >>= shift;
+
+	if (likely(hi == 0))
+		return lo;
+
+	return ((u64)hi << 32) | lo;
+}
+#define vdso_shift_ns vdso_shift_ns
+#endif
+
+#ifdef __powerpc64__
+int __c_kernel_clock_gettime(clockid_t clock, struct __kernel_timespec *ts,
+			     const struct vdso_data *vd);
+int __c_kernel_clock_getres(clockid_t clock_id, struct __kernel_timespec *res,
+			    const struct vdso_data *vd);
+#else
+int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
+			     const struct vdso_data *vd);
+int __c_kernel_clock_getres(clockid_t clock_id, struct old_timespec32 *res,
+			    const struct vdso_data *vd);
+#endif
+int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
+			    const struct vdso_data *vd);
+__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time,
+				    const struct vdso_data *vd);
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_VDSO_GETTIMEOFDAY_H */
diff --git a/arch/powerpc/kernel/vdso32/vgettimeofday.c b/arch/powerpc/kernel/vdso32/vgettimeofday.c
new file mode 100644
index 000000000000..0b9ab4c22ef2
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/vgettimeofday.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Powerpc userspace implementations of gettimeofday() and similar.
+ */
+#include <linux/time.h>
+#include <linux/types.h>
+
+int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
+			     const struct vdso_data *vd)
+{
+	return __cvdso_clock_gettime32_data(vd, clock, ts);
+}
+
+int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_gettimeofday_data(vd, tv, tz);
+}
+
+int __c_kernel_clock_getres(clockid_t clock_id, struct old_timespec32 *res,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_clock_getres_time32_data(vd, clock_id, res);
+}
+
+__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time, const struct vdso_data *vd)
+{
+	return __cvdso_time_data(vd, time);
+}
diff --git a/arch/powerpc/kernel/vdso64/vgettimeofday.c b/arch/powerpc/kernel/vdso64/vgettimeofday.c
new file mode 100644
index 000000000000..5b5500058344
--- /dev/null
+++ b/arch/powerpc/kernel/vdso64/vgettimeofday.c
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Powerpc userspace implementations of gettimeofday() and similar.
+ */
+#include <linux/time.h>
+#include <linux/types.h>
+
+int __c_kernel_clock_gettime(clockid_t clock, struct __kernel_timespec *ts,
+			     const struct vdso_data *vd)
+{
+	return __cvdso_clock_gettime_data(vd, clock, ts);
+}
+
+int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_gettimeofday_data(vd, tv, tz);
+}
+
+int __c_kernel_clock_getres(clockid_t clock_id, struct __kernel_timespec *res,
+			    const struct vdso_data *vd)
+{
+	return __cvdso_clock_getres_data(vd, clock_id, res);
+}
+
+__kernel_old_time_t __c_kernel_time(__kernel_old_time_t *time, const struct vdso_data *vd)
+{
+	return __cvdso_time_data(vd, time);
+}
-- 
2.25.0

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v9 3/5] powerpc/vdso: Save and restore TOC pointer on PPC64
  2020-08-04 11:47 [PATCH v9 0/5] powerpc: switch VDSO to C implementation Christophe Leroy
  2020-08-04 11:47 ` [PATCH v9 1/5] powerpc/processor: Move cpu_relax() into asm/vdso/processor.h Christophe Leroy
  2020-08-04 11:47 ` [PATCH v9 2/5] powerpc/vdso: Prepare for switching VDSO to generic C implementation Christophe Leroy
@ 2020-08-04 11:47 ` Christophe Leroy
  2020-08-04 11:47   ` Christophe Leroy
  2020-08-04 11:47 ` [PATCH v9 4/5] powerpc/vdso: Switch VDSO to generic C implementation Christophe Leroy
  2020-08-04 11:47 ` [PATCH v9 5/5] powerpc/vdso: Provide __kernel_clock_gettime64() on vdso32 Christophe Leroy
  4 siblings, 1 reply; 10+ messages in thread
From: Christophe Leroy @ 2020-08-04 11:47 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl, anton
  Cc: linux-kernel, linuxppc-dev, arnd, tglx, vincenzo.frascino, luto,
	linux-arch

On PPC64, the TOC pointer needs to be saved and restored.

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v9: New.

I'm not sure this is really needed, I can't see the VDSO C code doing
anything with r2, at least on ppc64_defconfig.

So I let you decide whether you take it or not.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/include/asm/vdso/gettimeofday.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
index 0b6fa245d54e..fa774086173b 100644
--- a/arch/powerpc/include/asm/vdso/gettimeofday.h
+++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
@@ -13,10 +13,16 @@
 	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
   .cfi_register lr, r0
 	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_STL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	get_datapage	r5, r0
 	addi		r5, r5, VDSO_DATA_OFFSET
 	bl		\funct
 	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_LL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	cmpwi		r3, 0
 	mtlr		r0
   .cfi_restore lr
@@ -36,10 +42,16 @@
 	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
   .cfi_register lr, r0
 	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_STL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	get_datapage	r4, r0
 	addi		r4, r4, VDSO_DATA_OFFSET
 	bl		\funct
 	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_LL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	crclr		so
 	mtlr		r0
   .cfi_restore lr
-- 
2.25.0

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v9 3/5] powerpc/vdso: Save and restore TOC pointer on PPC64
  2020-08-04 11:47 ` [PATCH v9 3/5] powerpc/vdso: Save and restore TOC pointer on PPC64 Christophe Leroy
@ 2020-08-04 11:47   ` Christophe Leroy
  0 siblings, 0 replies; 10+ messages in thread
From: Christophe Leroy @ 2020-08-04 11:47 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl, anton
  Cc: linux-kernel, linuxppc-dev, arnd, tglx, vincenzo.frascino, luto,
	linux-arch

On PPC64, the TOC pointer needs to be saved and restored.

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v9: New.

I'm not sure this is really needed, I can't see the VDSO C code doing
anything with r2, at least on ppc64_defconfig.

So I let you decide whether you take it or not.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/include/asm/vdso/gettimeofday.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/powerpc/include/asm/vdso/gettimeofday.h b/arch/powerpc/include/asm/vdso/gettimeofday.h
index 0b6fa245d54e..fa774086173b 100644
--- a/arch/powerpc/include/asm/vdso/gettimeofday.h
+++ b/arch/powerpc/include/asm/vdso/gettimeofday.h
@@ -13,10 +13,16 @@
 	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
   .cfi_register lr, r0
 	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_STL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	get_datapage	r5, r0
 	addi		r5, r5, VDSO_DATA_OFFSET
 	bl		\funct
 	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_LL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	cmpwi		r3, 0
 	mtlr		r0
   .cfi_restore lr
@@ -36,10 +42,16 @@
 	PPC_STLU	r1, -STACK_FRAME_OVERHEAD(r1)
   .cfi_register lr, r0
 	PPC_STL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_STL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	get_datapage	r4, r0
 	addi		r4, r4, VDSO_DATA_OFFSET
 	bl		\funct
 	PPC_LL		r0, STACK_FRAME_OVERHEAD + PPC_LR_STKOFF(r1)
+#ifdef CONFIG_PPC64
+	PPC_LL		r2, STACK_FRAME_OVERHEAD + STK_GOT(r1)
+#endif
 	crclr		so
 	mtlr		r0
   .cfi_restore lr
-- 
2.25.0

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v9 4/5] powerpc/vdso: Switch VDSO to generic C implementation.
  2020-08-04 11:47 [PATCH v9 0/5] powerpc: switch VDSO to C implementation Christophe Leroy
                   ` (2 preceding siblings ...)
  2020-08-04 11:47 ` [PATCH v9 3/5] powerpc/vdso: Save and restore TOC pointer on PPC64 Christophe Leroy
@ 2020-08-04 11:47 ` Christophe Leroy
  2020-08-04 11:47 ` [PATCH v9 5/5] powerpc/vdso: Provide __kernel_clock_gettime64() on vdso32 Christophe Leroy
  4 siblings, 0 replies; 10+ messages in thread
From: Christophe Leroy @ 2020-08-04 11:47 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl, anton
  Cc: linux-kernel, linuxppc-dev, arnd, tglx, vincenzo.frascino, luto,
	linux-arch

For VDSO32 on PPC64, we create a fake 32 bits config, on the same
principle as MIPS architecture, in order to get the correct parts of
the different asm header files.

With the C VDSO, the performance is slightly lower, but it is worth
it as it will ease maintenance and evolution, and also brings clocks
that are not supported with the ASM VDSO.

On an 8xx at 132 MHz, vdsotest with the ASM VDSO:
gettimeofday:    vdso: 828 nsec/call
clock-getres-realtime-coarse:    vdso: 391 nsec/call
clock-gettime-realtime-coarse:    vdso: 614 nsec/call
clock-getres-realtime:    vdso: 460 nsec/call
clock-gettime-realtime:    vdso: 876 nsec/call
clock-getres-monotonic-coarse:    vdso: 399 nsec/call
clock-gettime-monotonic-coarse:    vdso: 691 nsec/call
clock-getres-monotonic:    vdso: 460 nsec/call
clock-gettime-monotonic:    vdso: 1026 nsec/call

On an 8xx at 132 MHz, vdsotest with the C VDSO:
gettimeofday:    vdso: 955 nsec/call
clock-getres-realtime-coarse:    vdso: 545 nsec/call
clock-gettime-realtime-coarse:    vdso: 592 nsec/call
clock-getres-realtime:    vdso: 545 nsec/call
clock-gettime-realtime:    vdso: 941 nsec/call
clock-getres-monotonic-coarse:    vdso: 545 nsec/call
clock-gettime-monotonic-coarse:    vdso: 591 nsec/call
clock-getres-monotonic:    vdso: 545 nsec/call
clock-gettime-monotonic:    vdso: 940 nsec/call

It is even better for gettime with monotonic clocks.

Unsupported clocks with ASM VDSO:
clock-gettime-boottime:    vdso: 3851 nsec/call
clock-gettime-tai:    vdso: 3852 nsec/call
clock-gettime-monotonic-raw:    vdso: 3396 nsec/call

Same clocks with C VDSO:
clock-gettime-tai:    vdso: 941 nsec/call
clock-gettime-monotonic-raw:    vdso: 1001 nsec/call
clock-gettime-monotonic-coarse:    vdso: 591 nsec/call

On an 8321E at 333 MHz, vdsotest with the ASM VDSO:
gettimeofday:    vdso: 220 nsec/call
clock-getres-realtime-coarse:    vdso: 102 nsec/call
clock-gettime-realtime-coarse:    vdso: 178 nsec/call
clock-getres-realtime:    vdso: 129 nsec/call
clock-gettime-realtime:    vdso: 235 nsec/call
clock-getres-monotonic-coarse:    vdso: 105 nsec/call
clock-gettime-monotonic-coarse:    vdso: 208 nsec/call
clock-getres-monotonic:    vdso: 129 nsec/call
clock-gettime-monotonic:    vdso: 274 nsec/call

On an 8321E at 333 MHz, vdsotest with the C VDSO:
gettimeofday:    vdso: 272 nsec/call
clock-getres-realtime-coarse:    vdso: 160 nsec/call
clock-gettime-realtime-coarse:    vdso: 184 nsec/call
clock-getres-realtime:    vdso: 166 nsec/call
clock-gettime-realtime:    vdso: 281 nsec/call
clock-getres-monotonic-coarse:    vdso: 160 nsec/call
clock-gettime-monotonic-coarse:    vdso: 184 nsec/call
clock-getres-monotonic:    vdso: 169 nsec/call
clock-gettime-monotonic:    vdso: 275 nsec/call

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
v9:
- Rebased (Impact on arch/powerpc/kernel/vdso??/Makefile

v7:
- Split out preparatory changes in a new preceding patch
- Added -fasynchronous-unwind-tables to CC flags.

v6:
- Added missing prototypes in asm/vdso/gettimeofday.h for __c_kernel_ functions.
- Using STACK_FRAME_OVERHEAD instead of INT_FRAME_SIZE
- Rebased on powerpc/merge as of 7 Apr 2020
- Fixed build failure with gcc 9
- Added a patch to create asm/vdso/processor.h and more cpu_relax() in it

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/Kconfig                       |   2 +
 arch/powerpc/include/asm/vdso/vsyscall.h   |  25 ++
 arch/powerpc/include/asm/vdso_datapage.h   |  40 +--
 arch/powerpc/kernel/asm-offsets.c          |  49 +---
 arch/powerpc/kernel/time.c                 |  91 +------
 arch/powerpc/kernel/vdso.c                 |   5 +-
 arch/powerpc/kernel/vdso32/Makefile        |  32 ++-
 arch/powerpc/kernel/vdso32/config-fake32.h |  34 +++
 arch/powerpc/kernel/vdso32/gettimeofday.S  | 291 +--------------------
 arch/powerpc/kernel/vdso64/Makefile        |  23 +-
 arch/powerpc/kernel/vdso64/gettimeofday.S  | 242 +----------------
 11 files changed, 143 insertions(+), 691 deletions(-)
 create mode 100644 arch/powerpc/include/asm/vdso/vsyscall.h
 create mode 100644 arch/powerpc/kernel/vdso32/config-fake32.h

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 8c7656cc10eb..9977ab939b42 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -171,6 +171,7 @@ config PPC
 	select GENERIC_STRNCPY_FROM_USER
 	select GENERIC_STRNLEN_USER
 	select GENERIC_TIME_VSYSCALL
+	select GENERIC_GETTIMEOFDAY
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_HUGE_VMAP		if PPC_BOOK3S_64 && PPC_RADIX_MMU
 	select HAVE_ARCH_JUMP_LABEL
@@ -202,6 +203,7 @@ config PPC
 	select HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_FUNCTION_TRACER
 	select HAVE_GCC_PLUGINS			if GCC_VERSION >= 50200   # plugin support on gcc <= 5.1 is buggy on PPC
+	select HAVE_GENERIC_VDSO
 	select HAVE_HW_BREAKPOINT		if PERF_EVENTS && (PPC_BOOK3S || PPC_8xx)
 	select HAVE_IDE
 	select HAVE_IOREMAP_PROT
diff --git a/arch/powerpc/include/asm/vdso/vsyscall.h b/arch/powerpc/include/asm/vdso/vsyscall.h
new file mode 100644
index 000000000000..c56a030c0623
--- /dev/null
+++ b/arch/powerpc/include/asm/vdso/vsyscall.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_VDSO_VSYSCALL_H
+#define __ASM_VDSO_VSYSCALL_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/timekeeper_internal.h>
+#include <asm/vdso_datapage.h>
+
+/*
+ * Update the vDSO data page to keep in sync with kernel timekeeping.
+ */
+static __always_inline
+struct vdso_data *__arch_get_k_vdso_data(void)
+{
+	return vdso_data->data;
+}
+#define __arch_get_k_vdso_data __arch_get_k_vdso_data
+
+/* The asm-generic header needs to be included after the definitions above */
+#include <asm-generic/vdso/vsyscall.h>
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* __ASM_VDSO_VSYSCALL_H */
diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
index b9ef6cf50ea5..c4d320504d26 100644
--- a/arch/powerpc/include/asm/vdso_datapage.h
+++ b/arch/powerpc/include/asm/vdso_datapage.h
@@ -36,6 +36,7 @@
 
 #include <linux/unistd.h>
 #include <linux/time.h>
+#include <vdso/datapage.h>
 
 #define SYSCALL_MAP_SIZE      ((NR_syscalls + 31) / 32)
 
@@ -45,7 +46,7 @@
 
 #ifdef CONFIG_PPC64
 
-struct vdso_data {
+struct vdso_arch_data {
 	__u8  eye_catcher[16];		/* Eyecatcher: SYSTEMCFG:PPC64	0x00 */
 	struct {			/* Systemcfg version numbers	     */
 		__u32 major;		/* Major number			0x10 */
@@ -59,13 +60,13 @@ struct vdso_data {
 	__u32 processor;		/* Processor type		0x1C */
 	__u64 processorCount;		/* # of physical processors	0x20 */
 	__u64 physicalMemorySize;	/* Size of real memory(B)	0x28 */
-	__u64 tb_orig_stamp;		/* Timebase at boot		0x30 */
+	__u64 tb_orig_stamp;		/* (NU) Timebase at boot	0x30 */
 	__u64 tb_ticks_per_sec;		/* Timebase tics / sec		0x38 */
-	__u64 tb_to_xs;			/* Inverse of TB to 2^20	0x40 */
-	__u64 stamp_xsec;		/*				0x48 */
-	__u64 tb_update_count;		/* Timebase atomicity ctr	0x50 */
-	__u32 tz_minuteswest;		/* Minutes west of Greenwich	0x58 */
-	__u32 tz_dsttime;		/* Type of dst correction	0x5C */
+	__u64 tb_to_xs;			/* (NU) Inverse of TB to 2^20	0x40 */
+	__u64 stamp_xsec;		/* (NU)				0x48 */
+	__u64 tb_update_count;		/* (NU) Timebase atomicity ctr	0x50 */
+	__u32 tz_minuteswest;		/* (NU) Min. west of Greenwich	0x58 */
+	__u32 tz_dsttime;		/* (NU) Type of dst correction	0x5C */
 	__u32 dcache_size;		/* L1 d-cache size		0x60 */
 	__u32 dcache_line_size;		/* L1 d-cache line size		0x64 */
 	__u32 icache_size;		/* L1 i-cache size		0x68 */
@@ -78,14 +79,10 @@ struct vdso_data {
 	__u32 icache_block_size;		/* L1 i-cache block size     */
 	__u32 dcache_log_block_size;		/* L1 d-cache log block size */
 	__u32 icache_log_block_size;		/* L1 i-cache log block size */
-	__u32 stamp_sec_fraction;		/* fractional seconds of stamp_xtime */
-	__s32 wtom_clock_nsec;			/* Wall to monotonic clock nsec */
-	__s64 wtom_clock_sec;			/* Wall to monotonic clock sec */
-	__s64 stamp_xtime_sec;			/* xtime secs as at tb_orig_stamp */
-	__s64 stamp_xtime_nsec;			/* xtime nsecs as at tb_orig_stamp */
-	__u32 hrtimer_res;			/* hrtimer resolution */
    	__u32 syscall_map_64[SYSCALL_MAP_SIZE]; /* map of syscalls  */
    	__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
+
+	struct vdso_data data[CS_BASES];
 };
 
 #else /* CONFIG_PPC64 */
@@ -93,26 +90,15 @@ struct vdso_data {
 /*
  * And here is the simpler 32 bits version
  */
-struct vdso_data {
-	__u64 tb_orig_stamp;		/* Timebase at boot		0x30 */
+struct vdso_arch_data {
 	__u64 tb_ticks_per_sec;		/* Timebase tics / sec		0x38 */
-	__u64 tb_to_xs;			/* Inverse of TB to 2^20	0x40 */
-	__u64 stamp_xsec;		/*				0x48 */
-	__u32 tb_update_count;		/* Timebase atomicity ctr	0x50 */
-	__u32 tz_minuteswest;		/* Minutes west of Greenwich	0x58 */
-	__u32 tz_dsttime;		/* Type of dst correction	0x5C */
-	__s32 wtom_clock_sec;			/* Wall to monotonic clock */
-	__s32 wtom_clock_nsec;
-	__s32 stamp_xtime_sec;		/* xtime seconds as at tb_orig_stamp */
-	__s32 stamp_xtime_nsec;		/* xtime nsecs as at tb_orig_stamp */
-	__u32 stamp_sec_fraction;	/* fractional seconds of stamp_xtime */
-	__u32 hrtimer_res;		/* hrtimer resolution */
    	__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
+	struct vdso_data data[CS_BASES];
 };
 
 #endif /* CONFIG_PPC64 */
 
-extern struct vdso_data *vdso_data;
+extern struct vdso_arch_data *vdso_data;
 
 #else /* __ASSEMBLY__ */
 
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 8711c2164b45..684260186dbf 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -397,47 +397,16 @@ int main(void)
 #endif /* ! CONFIG_PPC64 */
 
 	/* datapage offsets for use by vdso */
-	OFFSET(CFG_TB_ORIG_STAMP, vdso_data, tb_orig_stamp);
-	OFFSET(CFG_TB_TICKS_PER_SEC, vdso_data, tb_ticks_per_sec);
-	OFFSET(CFG_TB_TO_XS, vdso_data, tb_to_xs);
-	OFFSET(CFG_TB_UPDATE_COUNT, vdso_data, tb_update_count);
-	OFFSET(CFG_TZ_MINUTEWEST, vdso_data, tz_minuteswest);
-	OFFSET(CFG_TZ_DSTTIME, vdso_data, tz_dsttime);
-	OFFSET(CFG_SYSCALL_MAP32, vdso_data, syscall_map_32);
-	OFFSET(WTOM_CLOCK_SEC, vdso_data, wtom_clock_sec);
-	OFFSET(WTOM_CLOCK_NSEC, vdso_data, wtom_clock_nsec);
-	OFFSET(STAMP_XTIME_SEC, vdso_data, stamp_xtime_sec);
-	OFFSET(STAMP_XTIME_NSEC, vdso_data, stamp_xtime_nsec);
-	OFFSET(STAMP_SEC_FRAC, vdso_data, stamp_sec_fraction);
-	OFFSET(CLOCK_HRTIMER_RES, vdso_data, hrtimer_res);
+	OFFSET(VDSO_DATA_OFFSET, vdso_arch_data, data);
+	OFFSET(CFG_TB_TICKS_PER_SEC, vdso_arch_data, tb_ticks_per_sec);
+	OFFSET(CFG_SYSCALL_MAP32, vdso_arch_data, syscall_map_32);
 #ifdef CONFIG_PPC64
-	OFFSET(CFG_ICACHE_BLOCKSZ, vdso_data, icache_block_size);
-	OFFSET(CFG_DCACHE_BLOCKSZ, vdso_data, dcache_block_size);
-	OFFSET(CFG_ICACHE_LOGBLOCKSZ, vdso_data, icache_log_block_size);
-	OFFSET(CFG_DCACHE_LOGBLOCKSZ, vdso_data, dcache_log_block_size);
-	OFFSET(CFG_SYSCALL_MAP64, vdso_data, syscall_map_64);
-	OFFSET(TVAL64_TV_SEC, __kernel_old_timeval, tv_sec);
-	OFFSET(TVAL64_TV_USEC, __kernel_old_timeval, tv_usec);
-#endif
-	OFFSET(TSPC64_TV_SEC, __kernel_timespec, tv_sec);
-	OFFSET(TSPC64_TV_NSEC, __kernel_timespec, tv_nsec);
-	OFFSET(TVAL32_TV_SEC, old_timeval32, tv_sec);
-	OFFSET(TVAL32_TV_USEC, old_timeval32, tv_usec);
-	OFFSET(TSPC32_TV_SEC, old_timespec32, tv_sec);
-	OFFSET(TSPC32_TV_NSEC, old_timespec32, tv_nsec);
-	/* timeval/timezone offsets for use by vdso */
-	OFFSET(TZONE_TZ_MINWEST, timezone, tz_minuteswest);
-	OFFSET(TZONE_TZ_DSTTIME, timezone, tz_dsttime);
-
-	/* Other bits used by the vdso */
-	DEFINE(CLOCK_REALTIME, CLOCK_REALTIME);
-	DEFINE(CLOCK_MONOTONIC, CLOCK_MONOTONIC);
-	DEFINE(CLOCK_REALTIME_COARSE, CLOCK_REALTIME_COARSE);
-	DEFINE(CLOCK_MONOTONIC_COARSE, CLOCK_MONOTONIC_COARSE);
-	DEFINE(CLOCK_MAX, CLOCK_TAI);
-	DEFINE(NSEC_PER_SEC, NSEC_PER_SEC);
-	DEFINE(EINVAL, EINVAL);
-	DEFINE(KTIME_LOW_RES, KTIME_LOW_RES);
+	OFFSET(CFG_ICACHE_BLOCKSZ, vdso_arch_data, icache_block_size);
+	OFFSET(CFG_DCACHE_BLOCKSZ, vdso_arch_data, dcache_block_size);
+	OFFSET(CFG_ICACHE_LOGBLOCKSZ, vdso_arch_data, icache_log_block_size);
+	OFFSET(CFG_DCACHE_LOGBLOCKSZ, vdso_arch_data, dcache_log_block_size);
+	OFFSET(CFG_SYSCALL_MAP64, vdso_arch_data, syscall_map_64);
+#endif
 
 #ifdef CONFIG_BUG
 	DEFINE(BUG_ENTRY_SIZE, sizeof(struct bug_entry));
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 6fcae436ae51..b63b1f97a1b3 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -91,6 +91,7 @@ static struct clocksource clocksource_timebase = {
 	.flags        = CLOCK_SOURCE_IS_CONTINUOUS,
 	.mask         = CLOCKSOURCE_MASK(64),
 	.read         = timebase_read,
+	.vdso_clock_mode	= VDSO_CLOCKMODE_ARCHTIMER,
 };
 
 #define DECREMENTER_DEFAULT_MAX 0x7FFFFFFF
@@ -855,95 +856,6 @@ static notrace u64 timebase_read(struct clocksource *cs)
 	return (u64)get_tb();
 }
 
-
-void update_vsyscall(struct timekeeper *tk)
-{
-	struct timespec64 xt;
-	struct clocksource *clock = tk->tkr_mono.clock;
-	u32 mult = tk->tkr_mono.mult;
-	u32 shift = tk->tkr_mono.shift;
-	u64 cycle_last = tk->tkr_mono.cycle_last;
-	u64 new_tb_to_xs, new_stamp_xsec;
-	u64 frac_sec;
-
-	if (clock != &clocksource_timebase)
-		return;
-
-	xt.tv_sec = tk->xtime_sec;
-	xt.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
-
-	/* Make userspace gettimeofday spin until we're done. */
-	++vdso_data->tb_update_count;
-	smp_mb();
-
-	/*
-	 * This computes ((2^20 / 1e9) * mult) >> shift as a
-	 * 0.64 fixed-point fraction.
-	 * The computation in the else clause below won't overflow
-	 * (as long as the timebase frequency is >= 1.049 MHz)
-	 * but loses precision because we lose the low bits of the constant
-	 * in the shift.  Note that 19342813113834067 ~= 2^(20+64) / 1e9.
-	 * For a shift of 24 the error is about 0.5e-9, or about 0.5ns
-	 * over a second.  (Shift values are usually 22, 23 or 24.)
-	 * For high frequency clocks such as the 512MHz timebase clock
-	 * on POWER[6789], the mult value is small (e.g. 32768000)
-	 * and so we can shift the constant by 16 initially
-	 * (295147905179 ~= 2^(20+64-16) / 1e9) and then do the
-	 * remaining shifts after the multiplication, which gives a
-	 * more accurate result (e.g. with mult = 32768000, shift = 24,
-	 * the error is only about 1.2e-12, or 0.7ns over 10 minutes).
-	 */
-	if (mult <= 62500000 && clock->shift >= 16)
-		new_tb_to_xs = ((u64) mult * 295147905179ULL) >> (clock->shift - 16);
-	else
-		new_tb_to_xs = (u64) mult * (19342813113834067ULL >> clock->shift);
-
-	/*
-	 * Compute the fractional second in units of 2^-32 seconds.
-	 * The fractional second is tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift
-	 * in nanoseconds, so multiplying that by 2^32 / 1e9 gives
-	 * it in units of 2^-32 seconds.
-	 * We assume shift <= 32 because clocks_calc_mult_shift()
-	 * generates shift values in the range 0 - 32.
-	 */
-	frac_sec = tk->tkr_mono.xtime_nsec << (32 - shift);
-	do_div(frac_sec, NSEC_PER_SEC);
-
-	/*
-	 * Work out new stamp_xsec value for any legacy users of systemcfg.
-	 * stamp_xsec is in units of 2^-20 seconds.
-	 */
-	new_stamp_xsec = frac_sec >> 12;
-	new_stamp_xsec += tk->xtime_sec * XSEC_PER_SEC;
-
-	/*
-	 * tb_update_count is used to allow the userspace gettimeofday code
-	 * to assure itself that it sees a consistent view of the tb_to_xs and
-	 * stamp_xsec variables.  It reads the tb_update_count, then reads
-	 * tb_to_xs and stamp_xsec and then reads tb_update_count again.  If
-	 * the two values of tb_update_count match and are even then the
-	 * tb_to_xs and stamp_xsec values are consistent.  If not, then it
-	 * loops back and reads them again until this criteria is met.
-	 */
-	vdso_data->tb_orig_stamp = cycle_last;
-	vdso_data->stamp_xsec = new_stamp_xsec;
-	vdso_data->tb_to_xs = new_tb_to_xs;
-	vdso_data->wtom_clock_sec = tk->wall_to_monotonic.tv_sec;
-	vdso_data->wtom_clock_nsec = tk->wall_to_monotonic.tv_nsec;
-	vdso_data->stamp_xtime_sec = xt.tv_sec;
-	vdso_data->stamp_xtime_nsec = xt.tv_nsec;
-	vdso_data->stamp_sec_fraction = frac_sec;
-	vdso_data->hrtimer_res = hrtimer_resolution;
-	smp_wmb();
-	++(vdso_data->tb_update_count);
-}
-
-void update_vsyscall_tz(void)
-{
-	vdso_data->tz_minuteswest = sys_tz.tz_minuteswest;
-	vdso_data->tz_dsttime = sys_tz.tz_dsttime;
-}
-
 static void __init clocksource_init(void)
 {
 	struct clocksource *clock;
@@ -1113,7 +1025,6 @@ void __init time_init(void)
 		sys_tz.tz_dsttime = 0;
 	}
 
-	vdso_data->tb_update_count = 0;
 	vdso_data->tb_ticks_per_sec = tb_ticks_per_sec;
 
 	/* initialise and enable the large decrementer (if we have one) */
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 8dad44262e75..23208a051af5 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -17,6 +17,7 @@
 #include <linux/elf.h>
 #include <linux/security.h>
 #include <linux/memblock.h>
+#include <vdso/datapage.h>
 
 #include <asm/processor.h>
 #include <asm/mmu.h>
@@ -70,10 +71,10 @@ static int vdso_ready;
  * with it, it will become dynamically allocated
  */
 static union {
-	struct vdso_data	data;
+	struct vdso_arch_data	data;
 	u8			page[PAGE_SIZE];
 } vdso_data_store __page_aligned_data;
-struct vdso_data *vdso_data = &vdso_data_store.data;
+struct vdso_arch_data *vdso_data = &vdso_data_store.data;
 
 /* Format of the patch table */
 struct vdso_patch_def
diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
index 87ab1152d5ce..b922044236dd 100644
--- a/arch/powerpc/kernel/vdso32/Makefile
+++ b/arch/powerpc/kernel/vdso32/Makefile
@@ -2,7 +2,23 @@
 
 # List of files in the vdso, has to be asm only for now
 
-obj-vdso32 = sigtramp.o gettimeofday.o datapage.o cacheflush.o note.o getcpu.o
+ARCH_REL_TYPE_ABS := R_PPC_JUMP_SLOT|R_PPC_GLOB_DAT|R_PPC_ADDR32|R_PPC_ADDR24|R_PPC_ADDR16|R_PPC_ADDR16_LO|R_PPC_ADDR16_HI|R_PPC_ADDR16_HA|R_PPC_ADDR14|R_PPC_ADDR14_BRTAKEN|R_PPC_ADDR14_BRNTAKEN
+include $(srctree)/lib/vdso/Makefile
+
+obj-vdso32 = sigtramp.o datapage.o cacheflush.o note.o getcpu.o $(obj-vdso32-y)
+obj-vdso32 += gettimeofday.o
+
+ifneq ($(c-gettimeofday-y),)
+  ifdef CONFIG_PPC64
+    CFLAGS_vgettimeofday.o += -include $(srctree)/$(src)/config-fake32.h
+  endif
+  CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
+  CFLAGS_vgettimeofday.o += $(DISABLE_LATENT_ENTROPY_PLUGIN)
+  CFLAGS_vgettimeofday.o += $(call cc-option, -fno-stack-protector)
+  CFLAGS_vgettimeofday.o += -DDISABLE_BRANCH_PROFILING
+  CFLAGS_vgettimeofday.o += -ffreestanding -fasynchronous-unwind-tables
+  CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE)
+endif
 
 # Build rules
 
@@ -15,6 +31,7 @@ endif
 CC32FLAGS :=
 ifdef CONFIG_PPC64
 CC32FLAGS += -m32
+KBUILD_CFLAGS := $(filter-out -mcmodel=medium,$(KBUILD_CFLAGS))
 endif
 
 targets := $(obj-vdso32) vdso32.so vdso32.so.dbg
@@ -23,6 +40,7 @@ obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32))
 GCOV_PROFILE := n
 KCOV_INSTRUMENT := n
 UBSAN_SANITIZE := n
+KASAN_SANITIZE := n
 
 ccflags-y := -shared -fno-common -fno-builtin -nostdlib \
 	-Wl,-soname=linux-vdso32.so.1 -Wl,--hash-style=both
@@ -36,8 +54,8 @@ CPPFLAGS_vdso32.lds += -P -C -Upowerpc
 $(obj)/vdso32_wrapper.o : $(obj)/vdso32.so
 
 # link rule for the .so file, .lds has to be first
-$(obj)/vdso32.so.dbg: $(src)/vdso32.lds $(obj-vdso32) FORCE
-	$(call if_changed,vdso32ld)
+$(obj)/vdso32.so.dbg: $(src)/vdso32.lds $(obj-vdso32) $(obj)/vgettimeofday.o FORCE
+	$(call if_changed,vdso32ld_and_check)
 
 # strip rule for the .so file
 $(obj)/%.so: OBJCOPYFLAGS := -S
@@ -47,12 +65,16 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
 # assembly rules for the .S files
 $(obj-vdso32): %.o: %.S FORCE
 	$(call if_changed_dep,vdso32as)
+$(obj)/vgettimeofday.o: %.o: %.c FORCE
+	$(call if_changed_dep,vdso32cc)
 
 # actual build commands
-quiet_cmd_vdso32ld = VDSO32L $@
-      cmd_vdso32ld = $(VDSOCC) $(c_flags) $(CC32FLAGS) -o $@ $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn) -Wl,-T$(filter %.lds,$^) $(filter %.o,$^)
+quiet_cmd_vdso32ld_and_check = VDSO32L $@
+      cmd_vdso32ld_and_check = $(VDSOCC) $(c_flags) $(CC32FLAGS) -o $@ $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn) -Wl,-T$(filter %.lds,$^) $(filter %.o,$^) ; $(cmd_vdso_check)
 quiet_cmd_vdso32as = VDSO32A $@
       cmd_vdso32as = $(VDSOCC) $(a_flags) $(CC32FLAGS) -c -o $@ $<
+quiet_cmd_vdso32cc = VDSO32C $@
+      cmd_vdso32cc = $(VDSOCC) $(c_flags) $(CC32FLAGS) -c -o $@ $<
 
 # install commands for the unstripped file
 quiet_cmd_vdso_install = INSTALL $@
diff --git a/arch/powerpc/kernel/vdso32/config-fake32.h b/arch/powerpc/kernel/vdso32/config-fake32.h
new file mode 100644
index 000000000000..e16041fc15c9
--- /dev/null
+++ b/arch/powerpc/kernel/vdso32/config-fake32.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * In case of a 32 bit VDSO for a 64 bit kernel fake a 32 bit kernel
+ * configuration.
+ */
+
+#undef CONFIG_PPC64
+#undef CONFIG_64BIT
+#define CONFIG_PPC32
+#define CONFIG_32BIT 1
+#define CONFIG_GENERIC_ATOMIC64 1
+
+#ifdef CONFIG_PPC_BOOK3S_64
+#undef CONFIG_PPC_BOOK3S_64
+#undef CONFIG_PPC_PSERIES
+#define CONFIG_PPC_BOOK3S_32
+#else
+#define CONFIG_PPC_MMU_NOHASH_32
+#define CONFIG_FSL_BOOKE
+#endif
+
+#define CONFIG_TASK_SIZE	0
+#undef CONFIG_MMIOWB
+#undef CONFIG_PPC_SPLPAR
+#undef CONFIG_SPARSEMEM
+#undef CONFIG_PGTABLE_LEVELS
+#define CONFIG_PGTABLE_LEVELS	2
+#undef CONFIG_TRANSPARENT_HUGEPAGE
+#undef CONFIG_SPARSEMEM_VMEMMAP
+#undef CONFIG_FLATMEM
+#define CONFIG_FLATMEM
+#undef CONFIG_PPC_INDIRECT_MMIO
+#undef CONFIG_PPC_INDIRECT_PIO
+#undef CONFIG_EEH
diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S
index e7f8f9f1b3f4..fd7b01c51281 100644
--- a/arch/powerpc/kernel/vdso32/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso32/gettimeofday.S
@@ -12,13 +12,7 @@
 #include <asm/vdso_datapage.h>
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
-
-/* Offset for the low 32-bit part of a field of long type */
-#ifdef CONFIG_PPC64
-#define LOPART	4
-#else
-#define LOPART	0
-#endif
+#include <asm/vdso/gettimeofday.h>
 
 	.text
 /*
@@ -28,32 +22,7 @@
  *
  */
 V_FUNCTION_BEGIN(__kernel_gettimeofday)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr.	r10,r3			/* r10 saves tv */
-	mr	r11,r4			/* r11 saves tz */
-	get_datapage	r9, r0
-	beq	3f
-	LOAD_REG_IMMEDIATE(r7, 1000000)	/* load up USEC_PER_SEC */
-	bl	__do_get_tspec@local	/* get sec/usec from tb & kernel */
-	stw	r3,TVAL32_TV_SEC(r10)
-	stw	r4,TVAL32_TV_USEC(r10)
-
-3:	cmplwi	r11,0			/* check if tz is NULL */
-	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0
-	beqlr
-
-	lwz	r4,CFG_TZ_MINUTEWEST(r9)/* fill tz */
-	lwz	r5,CFG_TZ_DSTTIME(r9)
-	stw	r4,TZONE_TZ_MINWEST(r11)
-	stw	r5,TZONE_TZ_DSTTIME(r11)
-
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_gettimeofday
 V_FUNCTION_END(__kernel_gettimeofday)
 
 /*
@@ -63,127 +32,7 @@ V_FUNCTION_END(__kernel_gettimeofday)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_gettime)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmpli	cr0,r3,CLOCK_REALTIME
-	cmpli	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
-
-	cmpli	cr5,r3,CLOCK_REALTIME_COARSE
-	cmpli	cr6,r3,CLOCK_MONOTONIC_COARSE
-	cror	cr5*4+eq,cr5*4+eq,cr6*4+eq
-
-	cror	cr0*4+eq,cr0*4+eq,cr5*4+eq
-	bne	cr0, .Lgettime_fallback
-
-	mflr	r12			/* r12 saves lr */
-  .cfi_register lr,r12
-	mr	r11,r4			/* r11 saves tp */
-	get_datapage	r9, r0
-	LOAD_REG_IMMEDIATE(r7, NSEC_PER_SEC)	/* load up NSEC_PER_SEC */
-	beq	cr5, .Lcoarse_clocks
-.Lprecise_clocks:
-	bl	__do_get_tspec@local	/* get sec/nsec from tb & kernel */
-	bne	cr1, .Lfinish		/* not monotonic -> all done */
-
-	/*
-	 * CLOCK_MONOTONIC
-	 */
-
-	/* now we must fixup using wall to monotonic. We need to snapshot
-	 * that value and do the counter trick again. Fortunately, we still
-	 * have the counter value in r8 that was returned by __do_get_xsec.
-	 * At this point, r3,r4 contain our sec/nsec values, r5 and r6
-	 * can be used, r7 contains NSEC_PER_SEC.
-	 */
-
-	lwz	r5,(WTOM_CLOCK_SEC+LOPART)(r9)
-	lwz	r6,WTOM_CLOCK_NSEC(r9)
-
-	/* We now have our offset in r5,r6. We create a fake dependency
-	 * on that value and re-check the counter
-	 */
-	or	r0,r6,r5
-	xor	r0,r0,r0
-	add	r9,r9,r0
-	lwz	r0,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-        cmpl    cr0,r8,r0		/* check if updated */
-	bne-	.Lprecise_clocks
-	b	.Lfinish_monotonic
-
-	/*
-	 * For coarse clocks we get data directly from the vdso data page, so
-	 * we don't need to call __do_get_tspec, but we still need to do the
-	 * counter trick.
-	 */
-.Lcoarse_clocks:
-	lwz	r8,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-	andi.	r0,r8,1                 /* pending update ? loop */
-	bne-	.Lcoarse_clocks
-	add	r9,r9,r0		/* r0 is already 0 */
-
-	/*
-	 * CLOCK_REALTIME_COARSE, below values are needed for MONOTONIC_COARSE
-	 * too
-	 */
-	lwz	r3,STAMP_XTIME_SEC+LOPART(r9)
-	lwz	r4,STAMP_XTIME_NSEC+LOPART(r9)
-	bne	cr6,1f
-
-	/* CLOCK_MONOTONIC_COARSE */
-	lwz	r5,(WTOM_CLOCK_SEC+LOPART)(r9)
-	lwz	r6,WTOM_CLOCK_NSEC(r9)
-
-	/* check if counter has updated */
-	or	r0,r6,r5
-1:	or	r0,r0,r3
-	or	r0,r0,r4
-	xor	r0,r0,r0
-	add	r3,r3,r0
-	lwz	r0,CFG_TB_UPDATE_COUNT+LOPART(r9)
-	cmpl	cr0,r0,r8               /* check if updated */
-	bne-	.Lcoarse_clocks
-
-	/* Counter has not updated, so continue calculating proper values for
-	 * sec and nsec if monotonic coarse, or just return with the proper
-	 * values for realtime.
-	 */
-	bne	cr6, .Lfinish
-
-	/* Calculate and store result. Note that this mimics the C code,
-	 * which may cause funny results if nsec goes negative... is that
-	 * possible at all ?
-	 */
-.Lfinish_monotonic:
-	add	r3,r3,r5
-	add	r4,r4,r6
-	cmpw	cr0,r4,r7
-	cmpwi	cr1,r4,0
-	blt	1f
-	subf	r4,r7,r4
-	addi	r3,r3,1
-1:	bge	cr1, .Lfinish
-	addi	r3,r3,-1
-	add	r4,r4,r7
-
-.Lfinish:
-	stw	r3,TSPC32_TV_SEC(r11)
-	stw	r4,TSPC32_TV_NSEC(r11)
-
-	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-.Lgettime_fallback:
-	li	r0,__NR_clock_gettime
-  .cfi_restore lr
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_gettime
 V_FUNCTION_END(__kernel_clock_gettime)
 
 
@@ -194,37 +43,7 @@ V_FUNCTION_END(__kernel_clock_gettime)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_getres)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmplwi	cr0, r3, CLOCK_MAX
-	cmpwi	cr1, r3, CLOCK_REALTIME_COARSE
-	cmpwi	cr7, r3, CLOCK_MONOTONIC_COARSE
-	bgt	cr0, 99f
-	LOAD_REG_IMMEDIATE(r5, KTIME_LOW_RES)
-	beq	cr1, 1f
-	beq	cr7, 1f
-
-	mflr	r12
-  .cfi_register lr,r12
-	get_datapage	r3, r0
-	lwz	r5, CLOCK_HRTIMER_RES(r3)
-	mtlr	r12
-1:	li	r3,0
-	cmpli	cr0,r4,0
-	crclr	cr0*4+so
-	beqlr
-	stw	r3,TSPC32_TV_SEC(r4)
-	stw	r5,TSPC32_TV_NSEC(r4)
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-99:
-	li	r0,__NR_clock_getres
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_getres
 V_FUNCTION_END(__kernel_clock_getres)
 
 
@@ -235,105 +54,5 @@ V_FUNCTION_END(__kernel_clock_getres)
  *
  */
 V_FUNCTION_BEGIN(__kernel_time)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr	r11,r3			/* r11 holds t */
-	get_datapage	r9, r0
-
-	lwz	r3,STAMP_XTIME_SEC+LOPART(r9)
-
-	cmplwi	r11,0			/* check if t is NULL */
-	mtlr	r12
-	crclr	cr0*4+so
-	beqlr
-	stw	r3,0(r11)		/* store result at *t */
-	blr
-  .cfi_endproc
+	cvdso_call_time __c_kernel_time
 V_FUNCTION_END(__kernel_time)
-
-/*
- * This is the core of clock_gettime() and gettimeofday(),
- * it returns the current time in r3 (seconds) and r4.
- * On entry, r7 gives the resolution of r4, either USEC_PER_SEC
- * or NSEC_PER_SEC, giving r4 in microseconds or nanoseconds.
- * It expects the datapage ptr in r9 and doesn't clobber it.
- * It clobbers r0, r5 and r6.
- * On return, r8 contains the counter value that can be reused.
- * This clobbers cr0 but not any other cr field.
- */
-__do_get_tspec:
-  .cfi_startproc
-	/* Check for update count & load values. We use the low
-	 * order 32 bits of the update count
-	 */
-1:	lwz	r8,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-	andi.	r0,r8,1			/* pending update ? loop */
-	bne-	1b
-	xor	r0,r8,r8		/* create dependency */
-	add	r9,r9,r0
-
-	/* Load orig stamp (offset to TB) */
-	lwz	r5,CFG_TB_ORIG_STAMP(r9)
-	lwz	r6,(CFG_TB_ORIG_STAMP+4)(r9)
-
-	/* Get a stable TB value */
-2:	MFTBU(r3)
-	MFTBL(r4)
-	MFTBU(r0)
-	cmplw	cr0,r3,r0
-	bne-	2b
-
-	/* Subtract tb orig stamp and shift left 12 bits.
-	 */
-	subfc	r4,r6,r4
-	subfe	r0,r5,r3
-	slwi	r0,r0,12
-	rlwimi.	r0,r4,12,20,31
-	slwi	r4,r4,12
-
-	/*
-	 * Load scale factor & do multiplication.
-	 * We only use the high 32 bits of the tb_to_xs value.
-	 * Even with a 1GHz timebase clock, the high 32 bits of
-	 * tb_to_xs will be at least 4 million, so the error from
-	 * ignoring the low 32 bits will be no more than 0.25ppm.
-	 * The error will just make the clock run very very slightly
-	 * slow until the next time the kernel updates the VDSO data,
-	 * at which point the clock will catch up to the kernel's value,
-	 * so there is no long-term error accumulation.
-	 */
-	lwz	r5,CFG_TB_TO_XS(r9)	/* load values */
-	mulhwu	r4,r4,r5
-	li	r3,0
-
-	beq+	4f			/* skip high part computation if 0 */
-	mulhwu	r3,r0,r5
-	mullw	r5,r0,r5
-	addc	r4,r4,r5
-	addze	r3,r3
-4:
-	/* At this point, we have seconds since the xtime stamp
-	 * as a 32.32 fixed-point number in r3 and r4.
-	 * Load & add the xtime stamp.
-	 */
-	lwz	r5,STAMP_XTIME_SEC+LOPART(r9)
-	lwz	r6,STAMP_SEC_FRAC(r9)
-	addc	r4,r4,r6
-	adde	r3,r3,r5
-
-	/* We create a fake dependency on the result in r3/r4
-	 * and re-check the counter
-	 */
-	or	r6,r4,r3
-	xor	r0,r6,r6
-	add	r9,r9,r0
-	lwz	r0,(CFG_TB_UPDATE_COUNT+LOPART)(r9)
-        cmplw	cr0,r8,r0		/* check if updated */
-	bne-	1b
-
-	mulhwu	r4,r4,r7		/* convert to micro or nanoseconds */
-
-	blr
-  .cfi_endproc
diff --git a/arch/powerpc/kernel/vdso64/Makefile b/arch/powerpc/kernel/vdso64/Makefile
index 38c317f25141..7890d889f9c5 100644
--- a/arch/powerpc/kernel/vdso64/Makefile
+++ b/arch/powerpc/kernel/vdso64/Makefile
@@ -1,8 +1,20 @@
 # SPDX-License-Identifier: GPL-2.0
 # List of files in the vdso, has to be asm only for now
 
+ARCH_REL_TYPE_ABS := R_PPC_JUMP_SLOT|R_PPC_GLOB_DAT|R_PPC_ADDR32|R_PPC_ADDR24|R_PPC_ADDR16|R_PPC_ADDR16_LO|R_PPC_ADDR16_HI|R_PPC_ADDR16_HA|R_PPC_ADDR14|R_PPC_ADDR14_BRTAKEN|R_PPC_ADDR14_BRNTAKEN
+include $(srctree)/lib/vdso/Makefile
+
 obj-vdso64 = sigtramp.o gettimeofday.o datapage.o cacheflush.o note.o getcpu.o
 
+ifneq ($(c-gettimeofday-y),)
+  CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
+  CFLAGS_vgettimeofday.o += $(DISABLE_LATENT_ENTROPY_PLUGIN)
+  CFLAGS_vgettimeofday.o += $(call cc-option, -fno-stack-protector)
+  CFLAGS_vgettimeofday.o += -DDISABLE_BRANCH_PROFILING
+  CFLAGS_vgettimeofday.o += -ffreestanding -fasynchronous-unwind-tables
+  CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE)
+endif
+
 # Build rules
 
 targets := $(obj-vdso64) vdso64.so vdso64.so.dbg
@@ -11,6 +23,7 @@ obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))
 GCOV_PROFILE := n
 KCOV_INSTRUMENT := n
 UBSAN_SANITIZE := n
+KASAN_SANITIZE := n
 
 ccflags-y := -shared -fno-common -fno-builtin -nostdlib \
 	-Wl,-soname=linux-vdso64.so.1 -Wl,--hash-style=both
@@ -20,12 +33,14 @@ obj-y += vdso64_wrapper.o
 extra-y += vdso64.lds
 CPPFLAGS_vdso64.lds += -P -C -U$(ARCH)
 
+$(obj)/vgettimeofday.o: %.o: %.c FORCE
+
 # Force dependency (incbin is bad)
 $(obj)/vdso64_wrapper.o : $(obj)/vdso64.so
 
 # link rule for the .so file, .lds has to be first
-$(obj)/vdso64.so.dbg: $(src)/vdso64.lds $(obj-vdso64) FORCE
-	$(call if_changed,vdso64ld)
+$(obj)/vdso64.so.dbg: $(src)/vdso64.lds $(obj-vdso64) $(obj)/vgettimeofday.o FORCE
+	$(call if_changed,vdso64ld_and_check)
 
 # strip rule for the .so file
 $(obj)/%.so: OBJCOPYFLAGS := -S
@@ -33,8 +48,8 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
 	$(call if_changed,objcopy)
 
 # actual build commands
-quiet_cmd_vdso64ld = VDSO64L $@
-      cmd_vdso64ld = $(CC) $(c_flags) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^) $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn)
+quiet_cmd_vdso64ld_and_check = VDSO64L $@
+      cmd_vdso64ld_and_check = $(CC) $(c_flags) -o $@ -Wl,-T$(filter %.lds,$^) $(filter %.o,$^) $(call cc-ldoption, -Wl$(comma)--orphan-handling=warn); $(cmd_vdso_check)
 
 # install commands for the unstripped file
 quiet_cmd_vdso_install = INSTALL $@
diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S
index 20f8be40c653..d7a7bfb51081 100644
--- a/arch/powerpc/kernel/vdso64/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso64/gettimeofday.S
@@ -12,6 +12,7 @@
 #include <asm/vdso_datapage.h>
 #include <asm/asm-offsets.h>
 #include <asm/unistd.h>
+#include <asm/vdso/gettimeofday.h>
 
 	.text
 /*
@@ -21,31 +22,7 @@
  *
  */
 V_FUNCTION_BEGIN(__kernel_gettimeofday)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr	r11,r3			/* r11 holds tv */
-	mr	r10,r4			/* r10 holds tz */
-	get_datapage	r3, r0
-	cmpldi	r11,0			/* check if tv is NULL */
-	beq	2f
-	lis	r7,1000000@ha		/* load up USEC_PER_SEC */
-	addi	r7,r7,1000000@l
-	bl	V_LOCAL_FUNC(__do_get_tspec) /* get sec/us from tb & kernel */
-	std	r4,TVAL64_TV_SEC(r11)	/* store sec in tv */
-	std	r5,TVAL64_TV_USEC(r11)	/* store usec in tv */
-2:	cmpldi	r10,0			/* check if tz is NULL */
-	beq	1f
-	lwz	r4,CFG_TZ_MINUTEWEST(r3)/* fill tz */
-	lwz	r5,CFG_TZ_DSTTIME(r3)
-	stw	r4,TZONE_TZ_MINWEST(r10)
-	stw	r5,TZONE_TZ_DSTTIME(r10)
-1:	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0			/* always success */
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_gettimeofday
 V_FUNCTION_END(__kernel_gettimeofday)
 
 
@@ -56,120 +33,7 @@ V_FUNCTION_END(__kernel_gettimeofday)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_gettime)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmpwi	cr0,r3,CLOCK_REALTIME
-	cmpwi	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
-
-	cmpwi	cr5,r3,CLOCK_REALTIME_COARSE
-	cmpwi	cr6,r3,CLOCK_MONOTONIC_COARSE
-	cror	cr5*4+eq,cr5*4+eq,cr6*4+eq
-
-	cror	cr0*4+eq,cr0*4+eq,cr5*4+eq
-	bne	cr0,99f
-
-	mflr	r12			/* r12 saves lr */
-  .cfi_register lr,r12
-	mr	r11,r4			/* r11 saves tp */
-	get_datapage	r3, r0
-	lis	r7,NSEC_PER_SEC@h	/* want nanoseconds */
-	ori	r7,r7,NSEC_PER_SEC@l
-	beq	cr5,70f
-50:	bl	V_LOCAL_FUNC(__do_get_tspec)	/* get time from tb & kernel */
-	bne	cr1,80f			/* if not monotonic, all done */
-
-	/*
-	 * CLOCK_MONOTONIC
-	 */
-
-	/* now we must fixup using wall to monotonic. We need to snapshot
-	 * that value and do the counter trick again. Fortunately, we still
-	 * have the counter value in r8 that was returned by __do_get_tspec.
-	 * At this point, r4,r5 contain our sec/nsec values.
-	 */
-
-	ld	r6,WTOM_CLOCK_SEC(r3)
-	lwa	r9,WTOM_CLOCK_NSEC(r3)
-
-	/* We now have our result in r6,r9. We create a fake dependency
-	 * on that result and re-check the counter
-	 */
-	or	r0,r6,r9
-	xor	r0,r0,r0
-	add	r3,r3,r0
-	ld	r0,CFG_TB_UPDATE_COUNT(r3)
-        cmpld   cr0,r0,r8		/* check if updated */
-	bne-	50b
-	b	78f
-
-	/*
-	 * For coarse clocks we get data directly from the vdso data page, so
-	 * we don't need to call __do_get_tspec, but we still need to do the
-	 * counter trick.
-	 */
-70:	ld      r8,CFG_TB_UPDATE_COUNT(r3)
-	andi.   r0,r8,1                 /* pending update ? loop */
-	bne-    70b
-	add     r3,r3,r0		/* r0 is already 0 */
-
-	/*
-	 * CLOCK_REALTIME_COARSE, below values are needed for MONOTONIC_COARSE
-	 * too
-	 */
-	ld      r4,STAMP_XTIME_SEC(r3)
-	ld      r5,STAMP_XTIME_NSEC(r3)
-	bne     cr6,75f
-
-	/* CLOCK_MONOTONIC_COARSE */
-	ld	r6,WTOM_CLOCK_SEC(r3)
-	lwa     r9,WTOM_CLOCK_NSEC(r3)
-
-	/* check if counter has updated */
-	or      r0,r6,r9
-75:	or	r0,r0,r4
-	or	r0,r0,r5
-	xor     r0,r0,r0
-	add     r3,r3,r0
-	ld      r0,CFG_TB_UPDATE_COUNT(r3)
-	cmpld   cr0,r0,r8               /* check if updated */
-	bne-    70b
-
-	/* Counter has not updated, so continue calculating proper values for
-	 * sec and nsec if monotonic coarse, or just return with the proper
-	 * values for realtime.
-	 */
-	bne     cr6,80f
-
-	/* Add wall->monotonic offset and check for overflow or underflow */
-78:	add     r4,r4,r6
-	add     r5,r5,r9
-	cmpd    cr0,r5,r7
-	cmpdi   cr1,r5,0
-	blt     79f
-	subf    r5,r7,r5
-	addi    r4,r4,1
-79:	bge     cr1,80f
-	addi    r4,r4,-1
-	add     r5,r5,r7
-
-80:	std	r4,TSPC64_TV_SEC(r11)
-	std	r5,TSPC64_TV_NSEC(r11)
-
-	mtlr	r12
-	crclr	cr0*4+so
-	li	r3,0
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-99:
-	li	r0,__NR_clock_gettime
-  .cfi_restore lr
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_gettime
 V_FUNCTION_END(__kernel_clock_gettime)
 
 
@@ -180,34 +44,7 @@ V_FUNCTION_END(__kernel_clock_gettime)
  *
  */
 V_FUNCTION_BEGIN(__kernel_clock_getres)
-  .cfi_startproc
-	/* Check for supported clock IDs */
-	cmpwi	cr0,r3,CLOCK_REALTIME
-	cmpwi	cr1,r3,CLOCK_MONOTONIC
-	cror	cr0*4+eq,cr0*4+eq,cr1*4+eq
-	bne	cr0,99f
-
-	mflr	r12
-  .cfi_register lr,r12
-	get_datapage	r3, r0
-	lwz	r5, CLOCK_HRTIMER_RES(r3)
-	mtlr	r12
-	li	r3,0
-	cmpldi	cr0,r4,0
-	crclr	cr0*4+so
-	beqlr
-	std	r3,TSPC64_TV_SEC(r4)
-	std	r5,TSPC64_TV_NSEC(r4)
-	blr
-
-	/*
-	 * syscall fallback
-	 */
-99:
-	li	r0,__NR_clock_getres
-	sc
-	blr
-  .cfi_endproc
+	cvdso_call __c_kernel_clock_getres
 V_FUNCTION_END(__kernel_clock_getres)
 
 /*
@@ -217,74 +54,5 @@ V_FUNCTION_END(__kernel_clock_getres)
  *
  */
 V_FUNCTION_BEGIN(__kernel_time)
-  .cfi_startproc
-	mflr	r12
-  .cfi_register lr,r12
-
-	mr	r11,r3			/* r11 holds t */
-	get_datapage	r3, r0
-
-	ld	r4,STAMP_XTIME_SEC(r3)
-
-	cmpldi	r11,0			/* check if t is NULL */
-	beq	2f
-	std	r4,0(r11)		/* store result at *t */
-2:	mtlr	r12
-	crclr	cr0*4+so
-	mr	r3,r4
-	blr
-  .cfi_endproc
+	cvdso_call_time __c_kernel_time
 V_FUNCTION_END(__kernel_time)
-
-
-/*
- * This is the core of clock_gettime() and gettimeofday(),
- * it returns the current time in r4 (seconds) and r5.
- * On entry, r7 gives the resolution of r5, either USEC_PER_SEC
- * or NSEC_PER_SEC, giving r5 in microseconds or nanoseconds.
- * It expects the datapage ptr in r3 and doesn't clobber it.
- * It clobbers r0, r6 and r9.
- * On return, r8 contains the counter value that can be reused.
- * This clobbers cr0 but not any other cr field.
- */
-V_FUNCTION_BEGIN(__do_get_tspec)
-  .cfi_startproc
-	/* check for update count & load values */
-1:	ld	r8,CFG_TB_UPDATE_COUNT(r3)
-	andi.	r0,r8,1			/* pending update ? loop */
-	bne-	1b
-	xor	r0,r8,r8		/* create dependency */
-	add	r3,r3,r0
-
-	/* Get TB & offset it. We use the MFTB macro which will generate
-	 * workaround code for Cell.
-	 */
-	MFTB(r6)
-	ld	r9,CFG_TB_ORIG_STAMP(r3)
-	subf	r6,r9,r6
-
-	/* Scale result */
-	ld	r5,CFG_TB_TO_XS(r3)
-	sldi	r6,r6,12		/* compute time since stamp_xtime */
-	mulhdu	r6,r6,r5		/* in units of 2^-32 seconds */
-
-	/* Add stamp since epoch */
-	ld	r4,STAMP_XTIME_SEC(r3)
-	lwz	r5,STAMP_SEC_FRAC(r3)
-	or	r0,r4,r5
-	or	r0,r0,r6
-	xor	r0,r0,r0
-	add	r3,r3,r0
-	ld	r0,CFG_TB_UPDATE_COUNT(r3)
-	cmpld   r0,r8			/* check if updated */
-	bne-	1b			/* reload if so */
-
-	/* convert to seconds & nanoseconds and add to stamp */
-	add	r6,r6,r5		/* add on fractional seconds of xtime */
-	mulhwu	r5,r6,r7		/* compute micro or nanoseconds and */
-	srdi	r6,r6,32		/* seconds since stamp_xtime */
-	clrldi	r5,r5,32
-	add	r4,r4,r6
-	blr
-  .cfi_endproc
-V_FUNCTION_END(__do_get_tspec)
-- 
2.25.0

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v9 5/5] powerpc/vdso: Provide __kernel_clock_gettime64() on vdso32
  2020-08-04 11:47 [PATCH v9 0/5] powerpc: switch VDSO to C implementation Christophe Leroy
                   ` (3 preceding siblings ...)
  2020-08-04 11:47 ` [PATCH v9 4/5] powerpc/vdso: Switch VDSO to generic C implementation Christophe Leroy
@ 2020-08-04 11:47 ` Christophe Leroy
  2020-08-04 11:47   ` Christophe Leroy
  4 siblings, 1 reply; 10+ messages in thread
From: Christophe Leroy @ 2020-08-04 11:47 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl, anton
  Cc: linux-kernel, linuxppc-dev, arnd, tglx, vincenzo.frascino, luto,
	linux-arch

Provides __kernel_clock_gettime64() on vdso32. This is the
64 bits version of __kernel_clock_gettime() which is
y2038 compliant.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/vdso32/gettimeofday.S  | 9 +++++++++
 arch/powerpc/kernel/vdso32/vdso32.lds.S    | 1 +
 arch/powerpc/kernel/vdso32/vgettimeofday.c | 6 ++++++
 3 files changed, 16 insertions(+)

diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S
index fd7b01c51281..a6e29f880e0e 100644
--- a/arch/powerpc/kernel/vdso32/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso32/gettimeofday.S
@@ -35,6 +35,15 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
 	cvdso_call __c_kernel_clock_gettime
 V_FUNCTION_END(__kernel_clock_gettime)
 
+/*
+ * Exact prototype of clock_gettime64()
+ *
+ * int __kernel_clock_gettime64(clockid_t clock_id, struct __timespec64 *ts);
+ *
+ */
+V_FUNCTION_BEGIN(__kernel_clock_gettime64)
+	cvdso_call __c_kernel_clock_gettime64
+V_FUNCTION_END(__kernel_clock_gettime64)
 
 /*
  * Exact prototype of clock_getres()
diff --git a/arch/powerpc/kernel/vdso32/vdso32.lds.S b/arch/powerpc/kernel/vdso32/vdso32.lds.S
index 4c985467a668..582c5b046cc9 100644
--- a/arch/powerpc/kernel/vdso32/vdso32.lds.S
+++ b/arch/powerpc/kernel/vdso32/vdso32.lds.S
@@ -148,6 +148,7 @@ VERSION
 #ifndef CONFIG_PPC_BOOK3S_601
 		__kernel_gettimeofday;
 		__kernel_clock_gettime;
+		__kernel_clock_gettime64;
 		__kernel_clock_getres;
 		__kernel_time;
 		__kernel_get_tbfreq;
diff --git a/arch/powerpc/kernel/vdso32/vgettimeofday.c b/arch/powerpc/kernel/vdso32/vgettimeofday.c
index 0b9ab4c22ef2..f7f71fecf4ed 100644
--- a/arch/powerpc/kernel/vdso32/vgettimeofday.c
+++ b/arch/powerpc/kernel/vdso32/vgettimeofday.c
@@ -11,6 +11,12 @@ int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
 	return __cvdso_clock_gettime32_data(vd, clock, ts);
 }
 
+int __c_kernel_clock_gettime64(clockid_t clock, struct __kernel_timespec *ts,
+			       const struct vdso_data *vd)
+{
+	return __cvdso_clock_gettime_data(vd, clock, ts);
+}
+
 int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
 			    const struct vdso_data *vd)
 {
-- 
2.25.0

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH v9 5/5] powerpc/vdso: Provide __kernel_clock_gettime64() on vdso32
  2020-08-04 11:47 ` [PATCH v9 5/5] powerpc/vdso: Provide __kernel_clock_gettime64() on vdso32 Christophe Leroy
@ 2020-08-04 11:47   ` Christophe Leroy
  0 siblings, 0 replies; 10+ messages in thread
From: Christophe Leroy @ 2020-08-04 11:47 UTC (permalink / raw)
  To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman, nathanl, anton
  Cc: linux-kernel, linuxppc-dev, arnd, tglx, vincenzo.frascino, luto,
	linux-arch

Provides __kernel_clock_gettime64() on vdso32. This is the
64 bits version of __kernel_clock_gettime() which is
y2038 compliant.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/vdso32/gettimeofday.S  | 9 +++++++++
 arch/powerpc/kernel/vdso32/vdso32.lds.S    | 1 +
 arch/powerpc/kernel/vdso32/vgettimeofday.c | 6 ++++++
 3 files changed, 16 insertions(+)

diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S
index fd7b01c51281..a6e29f880e0e 100644
--- a/arch/powerpc/kernel/vdso32/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso32/gettimeofday.S
@@ -35,6 +35,15 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
 	cvdso_call __c_kernel_clock_gettime
 V_FUNCTION_END(__kernel_clock_gettime)
 
+/*
+ * Exact prototype of clock_gettime64()
+ *
+ * int __kernel_clock_gettime64(clockid_t clock_id, struct __timespec64 *ts);
+ *
+ */
+V_FUNCTION_BEGIN(__kernel_clock_gettime64)
+	cvdso_call __c_kernel_clock_gettime64
+V_FUNCTION_END(__kernel_clock_gettime64)
 
 /*
  * Exact prototype of clock_getres()
diff --git a/arch/powerpc/kernel/vdso32/vdso32.lds.S b/arch/powerpc/kernel/vdso32/vdso32.lds.S
index 4c985467a668..582c5b046cc9 100644
--- a/arch/powerpc/kernel/vdso32/vdso32.lds.S
+++ b/arch/powerpc/kernel/vdso32/vdso32.lds.S
@@ -148,6 +148,7 @@ VERSION
 #ifndef CONFIG_PPC_BOOK3S_601
 		__kernel_gettimeofday;
 		__kernel_clock_gettime;
+		__kernel_clock_gettime64;
 		__kernel_clock_getres;
 		__kernel_time;
 		__kernel_get_tbfreq;
diff --git a/arch/powerpc/kernel/vdso32/vgettimeofday.c b/arch/powerpc/kernel/vdso32/vgettimeofday.c
index 0b9ab4c22ef2..f7f71fecf4ed 100644
--- a/arch/powerpc/kernel/vdso32/vgettimeofday.c
+++ b/arch/powerpc/kernel/vdso32/vgettimeofday.c
@@ -11,6 +11,12 @@ int __c_kernel_clock_gettime(clockid_t clock, struct old_timespec32 *ts,
 	return __cvdso_clock_gettime32_data(vd, clock, ts);
 }
 
+int __c_kernel_clock_gettime64(clockid_t clock, struct __kernel_timespec *ts,
+			       const struct vdso_data *vd)
+{
+	return __cvdso_clock_gettime_data(vd, clock, ts);
+}
+
 int __c_kernel_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz,
 			    const struct vdso_data *vd)
 {
-- 
2.25.0

^ permalink raw reply related	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2020-08-04 11:51 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-08-04 11:47 [PATCH v9 0/5] powerpc: switch VDSO to C implementation Christophe Leroy
2020-08-04 11:47 ` [PATCH v9 1/5] powerpc/processor: Move cpu_relax() into asm/vdso/processor.h Christophe Leroy
2020-08-04 11:47   ` Christophe Leroy
2020-08-04 11:47 ` [PATCH v9 2/5] powerpc/vdso: Prepare for switching VDSO to generic C implementation Christophe Leroy
2020-08-04 11:47   ` Christophe Leroy
2020-08-04 11:47 ` [PATCH v9 3/5] powerpc/vdso: Save and restore TOC pointer on PPC64 Christophe Leroy
2020-08-04 11:47   ` Christophe Leroy
2020-08-04 11:47 ` [PATCH v9 4/5] powerpc/vdso: Switch VDSO to generic C implementation Christophe Leroy
2020-08-04 11:47 ` [PATCH v9 5/5] powerpc/vdso: Provide __kernel_clock_gettime64() on vdso32 Christophe Leroy
2020-08-04 11:47   ` Christophe Leroy

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