aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm64/kernel/vdso/gettimeofday.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm64/kernel/vdso/gettimeofday.S')
-rw-r--r--arch/arm64/kernel/vdso/gettimeofday.S35
1 files changed, 15 insertions, 20 deletions
diff --git a/arch/arm64/kernel/vdso/gettimeofday.S b/arch/arm64/kernel/vdso/gettimeofday.S
index c39872a7b03c..80f780f56e0d 100644
--- a/arch/arm64/kernel/vdso/gettimeofday.S
+++ b/arch/arm64/kernel/vdso/gettimeofday.S
@@ -1,20 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
/*
* 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>
*/
@@ -73,6 +62,13 @@ x_tmp .req x8
movn x_tmp, #0xff00, lsl #48
and \res, x_tmp, \res
mul \res, \res, \mult
+ /*
+ * Fake address dependency from the value computed from the counter
+ * register to subsequent data page accesses so that the sequence
+ * locking also orders the read of the counter.
+ */
+ and x_tmp, \res, xzr
+ add vdso_data, vdso_data, x_tmp
.endm
/*
@@ -147,12 +143,12 @@ ENTRY(__kernel_gettimeofday)
/* 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
+ seqcnt_check fail=1b
get_ts_realtime res_sec=x10, res_nsec=x11, \
clock_nsec=x15, xtime_sec=x13, xtime_nsec=x14, nsec_to_sec=x9
@@ -211,13 +207,13 @@ realtime:
/* 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
+ seqcnt_check fail=realtime
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
@@ -231,7 +227,6 @@ monotonic:
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
@@ -239,6 +234,7 @@ monotonic:
lsl x9, x9, x12
get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11
+ seqcnt_check fail=monotonic
get_ts_realtime res_sec=x10, res_nsec=x11, \
clock_nsec=x15, xtime_sec=x13, xtime_nsec=x14, nsec_to_sec=x9
@@ -253,13 +249,13 @@ monotonic_raw:
/* 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
+ seqcnt_check fail=monotonic_raw
get_ts_clock_raw res_sec=x10, res_nsec=x11, \
clock_nsec=x15, nsec_to_sec=x9
@@ -301,13 +297,14 @@ ENTRY(__kernel_clock_getres)
ccmp w0, #CLOCK_MONOTONIC_RAW, #0x4, ne
b.ne 1f
- ldr x2, 5f
+ adr vdso_data, _vdso_data
+ ldr w2, [vdso_data, #CLOCK_REALTIME_RES]
b 2f
1:
cmp w0, #CLOCK_REALTIME_COARSE
ccmp w0, #CLOCK_MONOTONIC_COARSE, #0x4, ne
b.ne 4f
- ldr x2, 6f
+ ldr x2, 5f
2:
cbz x1, 3f
stp xzr, x2, [x1]
@@ -321,8 +318,6 @@ ENTRY(__kernel_clock_getres)
svc #0
ret
5:
- .quad CLOCK_REALTIME_RES
-6:
.quad CLOCK_COARSE_RES
.cfi_endproc
ENDPROC(__kernel_clock_getres)