FROMLIST: [PATCH v5 10/12] arm64: vdso: replace gettimeofday.S with global vgettimeof...
authorMark Salyzyn <salyzyn@google.com>
Fri, 4 Aug 2017 16:58:40 +0000 (09:58 -0700)
committerivanmeler <i_ivan@windowslive.com>
Wed, 13 Apr 2022 21:13:52 +0000 (21:13 +0000)
(cherry picked from url https://patchwork.kernel.org/patch/10044501/)

Take an effort from the previous 9 patches to recode the arm64 vdso
code from assembler to C previously submitted by
Andrew Pinski <apinski@cavium.com>, rework it for use in both arm and
arm64, overlapping any optimizations for each architecture. But
instead of landing it in arm64, land the result into lib/vdso and
unify both implementations to simplify future maintenance.

apinski@cavium.com makes the following claims in the original patch:

This allows the compiler to optimize the divide by 1000 and remove
the other divides.

On ThunderX, gettimeofday improves by 32%.  On ThunderX 2,
gettimeofday improves by 18%.

Note I noticed a bug in the old (arm64) implementation of
__kernel_clock_getres; it was checking only the lower 32bits of the
pointer; this would work for most cases but could fail in a few.

<end of claim>

Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Cc: James Morse <james.morse@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dmitry Safonov <dsafonov@virtuozzo.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andy Gross <andy.gross@linaro.org>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Andrew Pinski <apinski@cavium.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Bug: 63737556
Bug: 20045882
Change-Id: I71ff27ff5bfa323354fda6867b01ec908d8d6cbd

arch/arm64/include/asm/vdso_datapage.h
arch/arm64/kernel/asm-offsets.c
arch/arm64/kernel/vdso.c
arch/arm64/kernel/vdso/Makefile
arch/arm64/kernel/vdso/datapage.h [new file with mode: 0644]
arch/arm64/kernel/vdso/gettimeofday.S [deleted file]
arch/arm64/kernel/vdso/vgettimeofday.c [new file with mode: 0644]

index 2b9a63771eda8c81b12ec4279a9e279543739ecc..95f4a7abab803c9228577290731d76487c0a82fb 100644 (file)
 
 #ifndef __ASSEMBLY__
 
+#ifndef _VDSO_WTM_CLOCK_SEC_T
+#define _VDSO_WTM_CLOCK_SEC_T
+typedef __u64 vdso_wtm_clock_nsec_t;
+#endif
+
+#ifndef _VDSO_XTIME_CLOCK_SEC_T
+#define _VDSO_XTIME_CLOCK_SEC_T
+typedef __u64 vdso_xtime_clock_sec_t;
+#endif
+
+#ifndef _VDSO_RAW_TIME_SEC_T
+#define _VDSO_RAW_TIME_SEC_T
+typedef __u64 vdso_raw_time_sec_t;
+#endif
+
 struct vdso_data {
        __u64 cs_cycle_last;    /* Timebase at clocksource init */
-       __u64 raw_time_sec;     /* Raw time */
+       vdso_raw_time_sec_t raw_time_sec;       /* Raw time */
        __u64 raw_time_nsec;
-       __u64 xtime_clock_sec;  /* Kernel time */
-       __u64 xtime_clock_nsec;
+       vdso_xtime_clock_sec_t xtime_clock_sec; /* Kernel time */
+       __u64 xtime_clock_snsec;
        __u64 xtime_coarse_sec; /* Coarse time */
        __u64 xtime_coarse_nsec;
        __u64 wtm_clock_sec;    /* Wall to monotonic time */
-       __u64 wtm_clock_nsec;
+       vdso_wtm_clock_nsec_t wtm_clock_nsec;
        __u32 tb_seq_count;     /* Timebase sequence counter */
        /* cs_* members must be adjacent and in this order (ldp accesses) */
        __u32 cs_mono_mult;     /* NTP-adjusted clocksource multiplier */
index 3fa949f04ce4fb455a3bcafa7caa91fd61838596..f2d0391d387624e8a4e3a5af88ae26e0f2a0b45f 100644 (file)
@@ -84,40 +84,6 @@ int main(void)
   DEFINE(DMA_TO_DEVICE,                DMA_TO_DEVICE);
   DEFINE(DMA_FROM_DEVICE,      DMA_FROM_DEVICE);
   BLANK();
-  DEFINE(CLOCK_REALTIME,       CLOCK_REALTIME);
-  DEFINE(CLOCK_MONOTONIC,      CLOCK_MONOTONIC);
-  DEFINE(CLOCK_MONOTONIC_RAW,  CLOCK_MONOTONIC_RAW);
-  DEFINE(CLOCK_REALTIME_RES,   MONOTONIC_RES_NSEC);
-  DEFINE(CLOCK_REALTIME_COARSE,        CLOCK_REALTIME_COARSE);
-  DEFINE(CLOCK_MONOTONIC_COARSE,CLOCK_MONOTONIC_COARSE);
-  DEFINE(CLOCK_COARSE_RES,     LOW_RES_NSEC);
-  DEFINE(NSEC_PER_SEC,         NSEC_PER_SEC);
-  BLANK();
-  DEFINE(VDSO_CS_CYCLE_LAST,   offsetof(struct vdso_data, cs_cycle_last));
-  DEFINE(VDSO_RAW_TIME_SEC,    offsetof(struct vdso_data, raw_time_sec));
-  DEFINE(VDSO_RAW_TIME_NSEC,   offsetof(struct vdso_data, raw_time_nsec));
-  DEFINE(VDSO_XTIME_CLK_SEC,   offsetof(struct vdso_data, xtime_clock_sec));
-  DEFINE(VDSO_XTIME_CLK_NSEC,  offsetof(struct vdso_data, xtime_clock_nsec));
-  DEFINE(VDSO_XTIME_CRS_SEC,   offsetof(struct vdso_data, xtime_coarse_sec));
-  DEFINE(VDSO_XTIME_CRS_NSEC,  offsetof(struct vdso_data, xtime_coarse_nsec));
-  DEFINE(VDSO_WTM_CLK_SEC,     offsetof(struct vdso_data, wtm_clock_sec));
-  DEFINE(VDSO_WTM_CLK_NSEC,    offsetof(struct vdso_data, wtm_clock_nsec));
-  DEFINE(VDSO_TB_SEQ_COUNT,    offsetof(struct vdso_data, tb_seq_count));
-  DEFINE(VDSO_CS_MONO_MULT,    offsetof(struct vdso_data, cs_mono_mult));
-  DEFINE(VDSO_CS_RAW_MULT,     offsetof(struct vdso_data, cs_raw_mult));
-  DEFINE(VDSO_CS_SHIFT,                offsetof(struct vdso_data, cs_shift));
-  DEFINE(VDSO_TZ_MINWEST,      offsetof(struct vdso_data, tz_minuteswest));
-  DEFINE(VDSO_TZ_DSTTIME,      offsetof(struct vdso_data, tz_dsttime));
-  DEFINE(VDSO_USE_SYSCALL,     offsetof(struct vdso_data, use_syscall));
-  BLANK();
-  DEFINE(TVAL_TV_SEC,          offsetof(struct timeval, tv_sec));
-  DEFINE(TVAL_TV_USEC,         offsetof(struct timeval, tv_usec));
-  DEFINE(TSPEC_TV_SEC,         offsetof(struct timespec, tv_sec));
-  DEFINE(TSPEC_TV_NSEC,                offsetof(struct timespec, tv_nsec));
-  BLANK();
-  DEFINE(TZ_MINWEST,           offsetof(struct timezone, tz_minuteswest));
-  DEFINE(TZ_DSTTIME,           offsetof(struct timezone, tz_dsttime));
-  BLANK();
 #ifdef CONFIG_THREAD_INFO_IN_TASK
   DEFINE(CPU_BOOT_STACK,       offsetof(struct secondary_data, stack));
   DEFINE(CPU_BOOT_TASK,                offsetof(struct secondary_data, task));
index d119b22bed3660307d38abea61af8bab60f4d625..33bad6c004779c60bdddfd609d42a14d8deab8d6 100644 (file)
@@ -261,7 +261,7 @@ void update_vsyscall(struct timekeeper *tk)
                vdso_data->raw_time_sec         = tk->raw_sec;
                vdso_data->raw_time_nsec        = tk->tkr_raw.xtime_nsec;
                vdso_data->xtime_clock_sec      = tk->xtime_sec;
-               vdso_data->xtime_clock_nsec     = tk->tkr_mono.xtime_nsec;
+               vdso_data->xtime_clock_snsec    = tk->tkr_mono.xtime_nsec;
                /* tkr_raw.xtime_nsec == 0 */
                vdso_data->cs_mono_mult         = tk->tkr_mono.mult;
                vdso_data->cs_raw_mult          = tk->tkr_raw.mult;
index 62c84f7cb01b99e0105abef1d3bd3252249fc74c..83deb2a47de5026029cd99fd875e00c7e215828e 100644 (file)
@@ -5,18 +5,32 @@
 # Heavily based on the vDSO Makefiles for other archs.
 #
 
-obj-vdso := gettimeofday.o note.o sigreturn.o
+obj-vdso-s := note.o sigreturn.o
+obj-vdso-c := vgettimeofday.o
 
 # Build rules
-targets := $(obj-vdso) vdso.so vdso.so.dbg
-obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
+targets := $(obj-vdso-s) $(obj-vdso-c) vdso.so vdso.so.dbg
+obj-vdso-s := $(addprefix $(obj)/, $(obj-vdso-s))
+obj-vdso-c := $(addprefix $(obj)/, $(obj-vdso-c))
+obj-vdso   := $(obj-vdso-c) $(obj-vdso-s)
 
-ccflags-y := -shared -fno-common -fno-builtin
+ccflags-y := -shared -fno-common -fno-builtin -fno-stack-protector
+ccflags-y += -DDISABLE_BRANCH_PROFILING
 ccflags-y += -nostdlib -Wl,-soname=linux-vdso.so.1 \
                $(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
 
+# Force -O2 to avoid libgcc dependencies
+CFLAGS_REMOVE_vgettimeofday.o = -pg -Os
+CFLAGS_vgettimeofday.o = -O2 -fPIC
+ifneq ($(cc-name),clang)
+CFLAGS_vgettimeofday.o += -mcmodel=tiny
+endif
+
 # Disable gcov profiling for VDSO code
 GCOV_PROFILE := n
+KASAN_SANITIZE := n
+UBSAN_SANITIZE := n
+KCOV_INSTRUMENT := n
 
 # Workaround for bare-metal (ELF) toolchains that neglect to pass -shared
 # down to collect2, resulting in silent corruption of the vDSO image.
@@ -49,12 +63,17 @@ include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
        $(call if_changed,vdsosym)
 
 # Assembly rules for the .S files
-$(obj-vdso): %.o: %.S FORCE
+$(obj-vdso-s): %.o: %.S FORCE
        $(call if_changed_dep,vdsoas)
 
+$(obj-vdso-c): %.o: %.c FORCE
+       $(call if_changed_dep,vdsocc)
+
 # Actual build commands
 quiet_cmd_vdsold = VDSOL   $@
       cmd_vdsold = $(CC) $(c_flags) -Wl,-n -Wl,-T $^ -o $@
+quiet_cmd_vdsocc = VDSOC   $@
+      cmd_vdsocc = ${CC} $(c_flags) -c -o $@ $<
 quiet_cmd_vdsoas = VDSOA   $@
       cmd_vdsoas = $(CC) $(a_flags) -c -o $@ $<
 
diff --git a/arch/arm64/kernel/vdso/datapage.h b/arch/arm64/kernel/vdso/datapage.h
new file mode 100644 (file)
index 0000000..be86a60
--- /dev/null
@@ -0,0 +1,59 @@
+/*
+ * Userspace implementations of __get_datapage
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __VDSO_DATAPAGE_H
+#define __VDSO_DATAPAGE_H
+
+#include <linux/bitops.h>
+#include <linux/types.h>
+#include <asm/vdso_datapage.h>
+
+/*
+ * We use the hidden visibility to prevent the compiler from generating a GOT
+ * relocation. Not only is going through a GOT useless (the entry couldn't and
+ * mustn't be overridden by another library), it does not even work: the linker
+ * cannot generate an absolute address to the data page.
+ *
+ * With the hidden visibility, the compiler simply generates a PC-relative
+ * relocation (R_ARM_REL32), and this is what we need.
+ */
+extern const struct vdso_data _vdso_data __attribute__((visibility("hidden")));
+
+static inline const struct vdso_data *__get_datapage(void)
+{
+       const struct vdso_data *ret;
+       /*
+        * This simply puts &_vdso_data into ret. The reason why we don't use
+        * `ret = &_vdso_data` is that the compiler tends to optimise this in a
+        * very suboptimal way: instead of keeping &_vdso_data in a register,
+        * it goes through a relocation almost every time _vdso_data must be
+        * accessed (even in subfunctions). This is both time and space
+        * consuming: each relocation uses a word in the code section, and it
+        * has to be loaded at runtime.
+        *
+        * This trick hides the assignment from the compiler. Since it cannot
+        * track where the pointer comes from, it will only use one relocation
+        * where __get_datapage() is called, and then keep the result in a
+        * register.
+        */
+       asm("" : "=r"(ret) : "0"(&_vdso_data));
+       return ret;
+}
+
+/* We can only guarantee 56 bits of precision. */
+#define ARCH_CLOCK_FIXED_MASK GENMASK_ULL(55, 0)
+
+#endif /* __VDSO_DATAPAGE_H */
diff --git a/arch/arm64/kernel/vdso/gettimeofday.S b/arch/arm64/kernel/vdso/gettimeofday.S
deleted file mode 100644 (file)
index c39872a..0000000
+++ /dev/null
@@ -1,328 +0,0 @@
-/*
- * Userspace implementations of gettimeofday() and friends.
- *
- * Copyright (C) 2012 ARM Limited
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- *
- * Author: Will Deacon <will.deacon@arm.com>
- */
-
-#include <linux/linkage.h>
-#include <asm/asm-offsets.h>
-#include <asm/unistd.h>
-
-#define NSEC_PER_SEC_LO16      0xca00
-#define NSEC_PER_SEC_HI16      0x3b9a
-
-vdso_data      .req    x6
-seqcnt         .req    w7
-w_tmp          .req    w8
-x_tmp          .req    x8
-
-/*
- * Conventions for macro arguments:
- * - An argument is write-only if its name starts with "res".
- * - All other arguments are read-only, unless otherwise specified.
- */
-
-       .macro  seqcnt_acquire
-9999:  ldr     seqcnt, [vdso_data, #VDSO_TB_SEQ_COUNT]
-       tbnz    seqcnt, #0, 9999b
-       dmb     ishld
-       .endm
-
-       .macro  seqcnt_check fail
-       dmb     ishld
-       ldr     w_tmp, [vdso_data, #VDSO_TB_SEQ_COUNT]
-       cmp     w_tmp, seqcnt
-       b.ne    \fail
-       .endm
-
-       .macro  syscall_check fail
-       ldr     w_tmp, [vdso_data, #VDSO_USE_SYSCALL]
-       cbnz    w_tmp, \fail
-       .endm
-
-       .macro get_nsec_per_sec res
-       mov     \res, #NSEC_PER_SEC_LO16
-       movk    \res, #NSEC_PER_SEC_HI16, lsl #16
-       .endm
-
-       /*
-        * Returns the clock delta, in nanoseconds left-shifted by the clock
-        * shift.
-        */
-       .macro  get_clock_shifted_nsec res, cycle_last, mult
-       /* Read the virtual counter. */
-       isb
-       mrs     x_tmp, cntvct_el0
-       /* Calculate cycle delta and convert to ns. */
-       sub     \res, x_tmp, \cycle_last
-       /* We can only guarantee 56 bits of precision. */
-       movn    x_tmp, #0xff00, lsl #48
-       and     \res, x_tmp, \res
-       mul     \res, \res, \mult
-       .endm
-
-       /*
-        * Returns in res_{sec,nsec} the REALTIME timespec, based on the
-        * "wall time" (xtime) and the clock_mono delta.
-        */
-       .macro  get_ts_realtime res_sec, res_nsec, \
-                       clock_nsec, xtime_sec, xtime_nsec, nsec_to_sec
-       add     \res_nsec, \clock_nsec, \xtime_nsec
-       udiv    x_tmp, \res_nsec, \nsec_to_sec
-       add     \res_sec, \xtime_sec, x_tmp
-       msub    \res_nsec, x_tmp, \nsec_to_sec, \res_nsec
-       .endm
-
-       /*
-        * Returns in res_{sec,nsec} the timespec based on the clock_raw delta,
-        * used for CLOCK_MONOTONIC_RAW.
-        */
-       .macro  get_ts_clock_raw res_sec, res_nsec, clock_nsec, nsec_to_sec
-       udiv    \res_sec, \clock_nsec, \nsec_to_sec
-       msub    \res_nsec, \res_sec, \nsec_to_sec, \clock_nsec
-       .endm
-
-       /* sec and nsec are modified in place. */
-       .macro add_ts sec, nsec, ts_sec, ts_nsec, nsec_to_sec
-       /* Add timespec. */
-       add     \sec, \sec, \ts_sec
-       add     \nsec, \nsec, \ts_nsec
-
-       /* Normalise the new timespec. */
-       cmp     \nsec, \nsec_to_sec
-       b.lt    9999f
-       sub     \nsec, \nsec, \nsec_to_sec
-       add     \sec, \sec, #1
-9999:
-       cmp     \nsec, #0
-       b.ge    9998f
-       add     \nsec, \nsec, \nsec_to_sec
-       sub     \sec, \sec, #1
-9998:
-       .endm
-
-       .macro clock_gettime_return, shift=0
-       .if \shift == 1
-       lsr     x11, x11, x12
-       .endif
-       stp     x10, x11, [x1, #TSPEC_TV_SEC]
-       mov     x0, xzr
-       ret
-       .endm
-
-       .macro jump_slot jumptable, index, label
-       .if (. - \jumptable) != 4 * (\index)
-       .error "Jump slot index mismatch"
-       .endif
-       b       \label
-       .endm
-
-       .text
-
-/* int __kernel_gettimeofday(struct timeval *tv, struct timezone *tz); */
-ENTRY(__kernel_gettimeofday)
-       .cfi_startproc
-       adr     vdso_data, _vdso_data
-       /* If tv is NULL, skip to the timezone code. */
-       cbz     x0, 2f
-
-       /* Compute the time of day. */
-1:     seqcnt_acquire
-       syscall_check fail=4f
-       ldr     x10, [vdso_data, #VDSO_CS_CYCLE_LAST]
-       /* w11 = cs_mono_mult, w12 = cs_shift */
-       ldp     w11, w12, [vdso_data, #VDSO_CS_MONO_MULT]
-       ldp     x13, x14, [vdso_data, #VDSO_XTIME_CLK_SEC]
-       seqcnt_check fail=1b
-
-       get_nsec_per_sec res=x9
-       lsl     x9, x9, x12
-
-       get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11
-       get_ts_realtime res_sec=x10, res_nsec=x11, \
-               clock_nsec=x15, xtime_sec=x13, xtime_nsec=x14, nsec_to_sec=x9
-
-       /* Convert ns to us. */
-       mov     x13, #1000
-       lsl     x13, x13, x12
-       udiv    x11, x11, x13
-       stp     x10, x11, [x0, #TVAL_TV_SEC]
-2:
-       /* If tz is NULL, return 0. */
-       cbz     x1, 3f
-       ldp     w4, w5, [vdso_data, #VDSO_TZ_MINWEST]
-       stp     w4, w5, [x1, #TZ_MINWEST]
-3:
-       mov     x0, xzr
-       ret
-4:
-       /* Syscall fallback. */
-       mov     x8, #__NR_gettimeofday
-       svc     #0
-       ret
-       .cfi_endproc
-ENDPROC(__kernel_gettimeofday)
-
-#define JUMPSLOT_MAX CLOCK_MONOTONIC_COARSE
-
-/* int __kernel_clock_gettime(clockid_t clock_id, struct timespec *tp); */
-ENTRY(__kernel_clock_gettime)
-       .cfi_startproc
-       cmp     w0, #JUMPSLOT_MAX
-       b.hi    syscall
-       adr     vdso_data, _vdso_data
-       adr     x_tmp, jumptable
-       add     x_tmp, x_tmp, w0, uxtw #2
-       br      x_tmp
-
-       ALIGN
-jumptable:
-       jump_slot jumptable, CLOCK_REALTIME, realtime
-       jump_slot jumptable, CLOCK_MONOTONIC, monotonic
-       b       syscall
-       b       syscall
-       jump_slot jumptable, CLOCK_MONOTONIC_RAW, monotonic_raw
-       jump_slot jumptable, CLOCK_REALTIME_COARSE, realtime_coarse
-       jump_slot jumptable, CLOCK_MONOTONIC_COARSE, monotonic_coarse
-
-       .if (. - jumptable) != 4 * (JUMPSLOT_MAX + 1)
-       .error  "Wrong jumptable size"
-       .endif
-
-       ALIGN
-realtime:
-       seqcnt_acquire
-       syscall_check fail=syscall
-       ldr     x10, [vdso_data, #VDSO_CS_CYCLE_LAST]
-       /* w11 = cs_mono_mult, w12 = cs_shift */
-       ldp     w11, w12, [vdso_data, #VDSO_CS_MONO_MULT]
-       ldp     x13, x14, [vdso_data, #VDSO_XTIME_CLK_SEC]
-       seqcnt_check fail=realtime
-
-       /* All computations are done with left-shifted nsecs. */
-       get_nsec_per_sec res=x9
-       lsl     x9, x9, x12
-
-       get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11
-       get_ts_realtime res_sec=x10, res_nsec=x11, \
-               clock_nsec=x15, xtime_sec=x13, xtime_nsec=x14, nsec_to_sec=x9
-       clock_gettime_return, shift=1
-
-       ALIGN
-monotonic:
-       seqcnt_acquire
-       syscall_check fail=syscall
-       ldr     x10, [vdso_data, #VDSO_CS_CYCLE_LAST]
-       /* w11 = cs_mono_mult, w12 = cs_shift */
-       ldp     w11, w12, [vdso_data, #VDSO_CS_MONO_MULT]
-       ldp     x13, x14, [vdso_data, #VDSO_XTIME_CLK_SEC]
-       ldp     x3, x4, [vdso_data, #VDSO_WTM_CLK_SEC]
-       seqcnt_check fail=monotonic
-
-       /* All computations are done with left-shifted nsecs. */
-       lsl     x4, x4, x12
-       get_nsec_per_sec res=x9
-       lsl     x9, x9, x12
-
-       get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11
-       get_ts_realtime res_sec=x10, res_nsec=x11, \
-               clock_nsec=x15, xtime_sec=x13, xtime_nsec=x14, nsec_to_sec=x9
-
-       add_ts sec=x10, nsec=x11, ts_sec=x3, ts_nsec=x4, nsec_to_sec=x9
-       clock_gettime_return, shift=1
-
-       ALIGN
-monotonic_raw:
-       seqcnt_acquire
-       syscall_check fail=syscall
-       ldr     x10, [vdso_data, #VDSO_CS_CYCLE_LAST]
-       /* w11 = cs_raw_mult, w12 = cs_shift */
-       ldp     w12, w11, [vdso_data, #VDSO_CS_SHIFT]
-       ldp     x13, x14, [vdso_data, #VDSO_RAW_TIME_SEC]
-       seqcnt_check fail=monotonic_raw
-
-       /* All computations are done with left-shifted nsecs. */
-       get_nsec_per_sec res=x9
-       lsl     x9, x9, x12
-
-       get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11
-       get_ts_clock_raw res_sec=x10, res_nsec=x11, \
-               clock_nsec=x15, nsec_to_sec=x9
-
-       add_ts sec=x10, nsec=x11, ts_sec=x13, ts_nsec=x14, nsec_to_sec=x9
-       clock_gettime_return, shift=1
-
-       ALIGN
-realtime_coarse:
-       seqcnt_acquire
-       ldp     x10, x11, [vdso_data, #VDSO_XTIME_CRS_SEC]
-       seqcnt_check fail=realtime_coarse
-       clock_gettime_return
-
-       ALIGN
-monotonic_coarse:
-       seqcnt_acquire
-       ldp     x10, x11, [vdso_data, #VDSO_XTIME_CRS_SEC]
-       ldp     x13, x14, [vdso_data, #VDSO_WTM_CLK_SEC]
-       seqcnt_check fail=monotonic_coarse
-
-       /* Computations are done in (non-shifted) nsecs. */
-       get_nsec_per_sec res=x9
-       add_ts sec=x10, nsec=x11, ts_sec=x13, ts_nsec=x14, nsec_to_sec=x9
-       clock_gettime_return
-
-       ALIGN
-syscall: /* Syscall fallback. */
-       mov     x8, #__NR_clock_gettime
-       svc     #0
-       ret
-       .cfi_endproc
-ENDPROC(__kernel_clock_gettime)
-
-/* int __kernel_clock_getres(clockid_t clock_id, struct timespec *res); */
-ENTRY(__kernel_clock_getres)
-       .cfi_startproc
-       cmp     w0, #CLOCK_REALTIME
-       ccmp    w0, #CLOCK_MONOTONIC, #0x4, ne
-       ccmp    w0, #CLOCK_MONOTONIC_RAW, #0x4, ne
-       b.ne    1f
-
-       ldr     x2, 5f
-       b       2f
-1:
-       cmp     w0, #CLOCK_REALTIME_COARSE
-       ccmp    w0, #CLOCK_MONOTONIC_COARSE, #0x4, ne
-       b.ne    4f
-       ldr     x2, 6f
-2:
-       cbz     x1, 3f
-       stp     xzr, x2, [x1]
-
-3:     /* res == NULL. */
-       mov     w0, wzr
-       ret
-
-4:     /* Syscall fallback. */
-       mov     x8, #__NR_clock_getres
-       svc     #0
-       ret
-5:
-       .quad   CLOCK_REALTIME_RES
-6:
-       .quad   CLOCK_COARSE_RES
-       .cfi_endproc
-ENDPROC(__kernel_clock_getres)
diff --git a/arch/arm64/kernel/vdso/vgettimeofday.c b/arch/arm64/kernel/vdso/vgettimeofday.c
new file mode 100644 (file)
index 0000000..b73d401
--- /dev/null
@@ -0,0 +1,3 @@
+#include "compiler.h"
+#include "datapage.h"
+#include "../../../../lib/vdso/vgettimeofday.c"