Take an effort to recode the arm64 vdso code from assembler to C
previously submitted by Andrew Pinski <apin...@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.
Add ARCH_CLOCK_FIXED_MASK as an efficiency since arm64 has no
purpose for cs_mask vdso_data variable.
Signed-off-by: Mark Salyzyn <saly...@android.com>
Tested-by: Mark Salyzyn <saly...@android.com>
Cc: James Morse <james.mo...@arm.com>
Cc: Russell King <li...@armlinux.org.uk>
Cc: Catalin Marinas <catalin.mari...@arm.com>
Cc: Will Deacon <will.dea...@arm.com>
Cc: Andy Lutomirski <l...@amacapital.net>
Cc: Dmitry Safonov <dsafo...@virtuozzo.com>
Cc: John Stultz <john.stu...@linaro.org>
Cc: Mark Rutland <mark.rutl...@arm.com>
Cc: Laura Abbott <labb...@redhat.com>
Cc: Kees Cook <keesc...@chromium.org>
Cc: Ard Biesheuvel <ard.biesheu...@linaro.org>
Cc: Andy Gross <andy.gr...@linaro.org>
Cc: Kevin Brodsky <kevin.brod...@arm.com>
Cc: Andrew Pinski <apin...@cavium.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Cc: linux-arm-ker...@lists.infradead.org
Cc: Jeremy Linton <jeremy.lin...@arm.com>
Cc: android-ker...@android.com
v4:
- New in series, split off from earlier.
v5:
- rebase
---
arch/arm/vdso/vgettimeofday.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/arch/arm/vdso/vgettimeofday.c b/arch/arm/vdso/vgettimeofday.c
index a354586f8a65..3005479efbe8 100644
--- a/arch/arm/vdso/vgettimeofday.c
+++ b/arch/arm/vdso/vgettimeofday.c
@@ -128,7 +128,11 @@ static notrace int do_realtime(const struct vdso_data *vd,
struct timespec *ts)
{
u32 seq, mult, shift;
u64 nsec, cycle_last;
+#ifdef ARCH_CLOCK_FIXED_MASK
+ static const u64 mask = ARCH_CLOCK_FIXED_MASK;
+#else
u64 mask;
+#endif
vdso_xtime_clock_sec_t sec;
do {
@@ -141,7 +145,9 @@ static notrace int do_realtime(const struct vdso_data *vd,
struct timespec *ts)
mult = vd->cs_mono_mult;
shift = vd->cs_shift;
+#ifndef ARCH_CLOCK_FIXED_MASK
mask = vd->cs_mask;
+#endif
sec = vd->xtime_clock_sec;
nsec = vd->xtime_clock_snsec;
@@ -161,7 +167,11 @@ static notrace int do_monotonic(const struct vdso_data
*vd, struct timespec *ts)
{
u32 seq, mult, shift;
u64 nsec, cycle_last;
+#ifdef ARCH_CLOCK_FIXED_MASK
+ static const u64 mask = ARCH_CLOCK_FIXED_MASK;
+#else
u64 mask;
+#endif
vdso_wtm_clock_nsec_t wtm_nsec;
__kernel_time_t sec;
@@ -175,7 +185,9 @@ static notrace int do_monotonic(const struct vdso_data *vd,
struct timespec *ts)
mult = vd->cs_mono_mult;
shift = vd->cs_shift;
+#ifndef ARCH_CLOCK_FIXED_MASK
mask = vd->cs_mask;
+#endif
sec = vd->xtime_clock_sec;
nsec = vd->xtime_clock_snsec;
@@ -200,7 +212,11 @@ static notrace int do_monotonic_raw(const struct vdso_data
*vd,
{
u32 seq, mult, shift;
u64 nsec, cycle_last;
+#ifdef ARCH_CLOCK_FIXED_MASK
+ static const u64 mask = ARCH_CLOCK_FIXED_MASK;
+#else
u64 mask;
+#endif
vdso_raw_time_sec_t sec;
do {
@@ -213,7 +229,9 @@ static notrace int do_monotonic_raw(const struct vdso_data
*vd,
mult = vd->cs_raw_mult;
shift = vd->cs_shift;
+#ifndef ARCH_CLOCK_FIXED_MASK
mask = vd->cs_mask;
+#endif
sec = vd->raw_time_sec;
nsec = vd->raw_time_nsec;
--
2.19.0.605.g01d371f741-goog
