From 79c74ecbebf76732f91b82a62ce7fc8a88326962 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 22 Nov 2013 10:04:53 +0100 Subject: [PATCH] s390/time,vdso: convert to the new update_vsyscall interface Switch to the improved update_vsyscall interface that provides sub-nanosecond precision for gettimeofday and clock_gettime. Signed-off-by: Martin Schwidefsky --- arch/s390/Kconfig | 2 +- arch/s390/include/asm/vdso.h | 5 +++-- arch/s390/kernel/asm-offsets.c | 3 ++- arch/s390/kernel/time.c | 27 ++++++++++++++-------- arch/s390/kernel/vdso32/clock_gettime.S | 30 +++++++++++++------------ arch/s390/kernel/vdso32/gettimeofday.S | 9 ++++---- arch/s390/kernel/vdso64/clock_gettime.S | 22 +++++++++--------- arch/s390/kernel/vdso64/gettimeofday.S | 9 ++++---- 8 files changed, 62 insertions(+), 45 deletions(-) diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 314fced4fc14..5877e71901b3 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -101,7 +101,7 @@ config S390 select GENERIC_CPU_DEVICES if !SMP select GENERIC_FIND_FIRST_BIT select GENERIC_SMP_IDLE_THREAD - select GENERIC_TIME_VSYSCALL_OLD + select GENERIC_TIME_VSYSCALL select HAVE_ALIGNED_STRUCT_PAGE if SLUB select HAVE_ARCH_JUMP_LABEL if !MARCH_G5 select HAVE_ARCH_SECCOMP_FILTER diff --git a/arch/s390/include/asm/vdso.h b/arch/s390/include/asm/vdso.h index a73eb2e1e918..bc9746a7d47c 100644 --- a/arch/s390/include/asm/vdso.h +++ b/arch/s390/include/asm/vdso.h @@ -26,8 +26,9 @@ struct vdso_data { __u64 wtom_clock_nsec; /* 0x28 */ __u32 tz_minuteswest; /* Minutes west of Greenwich 0x30 */ __u32 tz_dsttime; /* Type of dst correction 0x34 */ - __u32 ectg_available; - __u32 ntp_mult; /* NTP adjusted multiplier 0x3C */ + __u32 ectg_available; /* ECTG instruction present 0x38 */ + __u32 tk_mult; /* Mult. used for xtime_nsec 0x3c */ + __u32 tk_shift; /* Shift used for xtime_nsec 0x40 */ }; struct vdso_per_cpu_data { diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c index 2416138ebd3e..496116cd65ec 100644 --- a/arch/s390/kernel/asm-offsets.c +++ b/arch/s390/kernel/asm-offsets.c @@ -65,7 +65,8 @@ int main(void) DEFINE(__VDSO_WTOM_NSEC, offsetof(struct vdso_data, wtom_clock_nsec)); DEFINE(__VDSO_TIMEZONE, offsetof(struct vdso_data, tz_minuteswest)); DEFINE(__VDSO_ECTG_OK, offsetof(struct vdso_data, ectg_available)); - DEFINE(__VDSO_NTP_MULT, offsetof(struct vdso_data, ntp_mult)); + DEFINE(__VDSO_TK_MULT, offsetof(struct vdso_data, tk_mult)); + DEFINE(__VDSO_TK_SHIFT, offsetof(struct vdso_data, tk_shift)); DEFINE(__VDSO_ECTG_BASE, offsetof(struct vdso_per_cpu_data, ectg_timer_base)); DEFINE(__VDSO_ECTG_USER, offsetof(struct vdso_per_cpu_data, ectg_user_time)); /* constants used by the vdso */ diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index 064c3082ab33..60a508a9b981 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -221,21 +221,30 @@ struct clocksource * __init clocksource_default_clock(void) return &clocksource_tod; } -void update_vsyscall_old(struct timespec *wall_time, struct timespec *wtm, - struct clocksource *clock, u32 mult) +void update_vsyscall(struct timekeeper *tk) { - if (clock != &clocksource_tod) + u64 nsecps; + + if (tk->clock != &clocksource_tod) return; /* Make userspace gettimeofday spin until we're done. */ ++vdso_data->tb_update_count; smp_wmb(); - vdso_data->xtime_tod_stamp = clock->cycle_last; - vdso_data->xtime_clock_sec = wall_time->tv_sec; - vdso_data->xtime_clock_nsec = wall_time->tv_nsec; - vdso_data->wtom_clock_sec = wtm->tv_sec; - vdso_data->wtom_clock_nsec = wtm->tv_nsec; - vdso_data->ntp_mult = mult; + vdso_data->xtime_tod_stamp = tk->clock->cycle_last; + vdso_data->xtime_clock_sec = tk->xtime_sec; + vdso_data->xtime_clock_nsec = tk->xtime_nsec; + vdso_data->wtom_clock_sec = + tk->xtime_sec + tk->wall_to_monotonic.tv_sec; + vdso_data->wtom_clock_nsec = tk->xtime_nsec + + + (tk->wall_to_monotonic.tv_nsec << tk->shift); + nsecps = (u64) NSEC_PER_SEC << tk->shift; + while (vdso_data->wtom_clock_nsec >= nsecps) { + vdso_data->wtom_clock_nsec -= nsecps; + vdso_data->wtom_clock_sec++; + } + vdso_data->tk_mult = tk->mult; + vdso_data->tk_shift = tk->shift; smp_wmb(); ++vdso_data->tb_update_count; } diff --git a/arch/s390/kernel/vdso32/clock_gettime.S b/arch/s390/kernel/vdso32/clock_gettime.S index b2224e0b974c..5be8e472f57d 100644 --- a/arch/s390/kernel/vdso32/clock_gettime.S +++ b/arch/s390/kernel/vdso32/clock_gettime.S @@ -38,25 +38,26 @@ __kernel_clock_gettime: sl %r1,__VDSO_XTIME_STAMP+4(%r5) brc 3,2f ahi %r0,-1 -2: ms %r0,__VDSO_NTP_MULT(%r5) /* cyc2ns(clock,cycle_delta) */ +2: ms %r0,__VDSO_TK_MULT(%r5) /* * tk->mult */ lr %r2,%r0 - l %r0,__VDSO_NTP_MULT(%r5) + l %r0,__VDSO_TK_MULT(%r5) ltr %r1,%r1 mr %r0,%r0 jnm 3f - a %r0,__VDSO_NTP_MULT(%r5) + a %r0,__VDSO_TK_MULT(%r5) 3: alr %r0,%r2 - srdl %r0,12 - al %r0,__VDSO_XTIME_NSEC(%r5) /* + xtime */ + al %r0,__VDSO_XTIME_NSEC(%r5) /* + tk->xtime_nsec */ al %r1,__VDSO_XTIME_NSEC+4(%r5) brc 12,4f ahi %r0,1 -4: l %r2,__VDSO_XTIME_SEC+4(%r5) - al %r0,__VDSO_WTOM_NSEC(%r5) /* + wall_to_monotonic */ +4: al %r0,__VDSO_WTOM_NSEC(%r5) /* + wall_to_monotonic.nsec */ al %r1,__VDSO_WTOM_NSEC+4(%r5) brc 12,5f ahi %r0,1 -5: al %r2,__VDSO_WTOM_SEC+4(%r5) +5: l %r2,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */ + srdl %r0,0(%r2) /* >> tk->shift */ + l %r2,__VDSO_XTIME_SEC+4(%r5) + al %r2,__VDSO_WTOM_SEC+4(%r5) cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */ jne 1b basr %r5,0 @@ -86,20 +87,21 @@ __kernel_clock_gettime: sl %r1,__VDSO_XTIME_STAMP+4(%r5) brc 3,12f ahi %r0,-1 -12: ms %r0,__VDSO_NTP_MULT(%r5) /* cyc2ns(clock,cycle_delta) */ +12: ms %r0,__VDSO_TK_MULT(%r5) /* * tk->mult */ lr %r2,%r0 - l %r0,__VDSO_NTP_MULT(%r5) + l %r0,__VDSO_TK_MULT(%r5) ltr %r1,%r1 mr %r0,%r0 jnm 13f - a %r0,__VDSO_NTP_MULT(%r5) + a %r0,__VDSO_TK_MULT(%r5) 13: alr %r0,%r2 - srdl %r0,12 - al %r0,__VDSO_XTIME_NSEC(%r5) /* + xtime */ + al %r0,__VDSO_XTIME_NSEC(%r5) /* + tk->xtime_nsec */ al %r1,__VDSO_XTIME_NSEC+4(%r5) brc 12,14f ahi %r0,1 -14: l %r2,__VDSO_XTIME_SEC+4(%r5) +14: l %r2,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */ + srdl %r0,0(%r2) /* >> tk->shift */ + l %r2,__VDSO_XTIME_SEC+4(%r5) cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */ jne 11b basr %r5,0 diff --git a/arch/s390/kernel/vdso32/gettimeofday.S b/arch/s390/kernel/vdso32/gettimeofday.S index 2d3633175e3b..fd621a950f7c 100644 --- a/arch/s390/kernel/vdso32/gettimeofday.S +++ b/arch/s390/kernel/vdso32/gettimeofday.S @@ -35,15 +35,14 @@ __kernel_gettimeofday: sl %r1,__VDSO_XTIME_STAMP+4(%r5) brc 3,3f ahi %r0,-1 -3: ms %r0,__VDSO_NTP_MULT(%r5) /* cyc2ns(clock,cycle_delta) */ +3: ms %r0,__VDSO_TK_MULT(%r5) /* * tk->mult */ st %r0,24(%r15) - l %r0,__VDSO_NTP_MULT(%r5) + l %r0,__VDSO_TK_MULT(%r5) ltr %r1,%r1 mr %r0,%r0 jnm 4f - a %r0,__VDSO_NTP_MULT(%r5) + a %r0,__VDSO_TK_MULT(%r5) 4: al %r0,24(%r15) - srdl %r0,12 al %r0,__VDSO_XTIME_NSEC(%r5) /* + xtime */ al %r1,__VDSO_XTIME_NSEC+4(%r5) brc 12,5f @@ -51,6 +50,8 @@ __kernel_gettimeofday: 5: mvc 24(4,%r15),__VDSO_XTIME_SEC+4(%r5) cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */ jne 1b + l %r4,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */ + srdl %r0,0(%r4) /* >> tk->shift */ l %r4,24(%r15) /* get tv_sec from stack */ basr %r5,0 6: ltr %r0,%r0 diff --git a/arch/s390/kernel/vdso64/clock_gettime.S b/arch/s390/kernel/vdso64/clock_gettime.S index d46c95ed5f19..0add1072ba30 100644 --- a/arch/s390/kernel/vdso64/clock_gettime.S +++ b/arch/s390/kernel/vdso64/clock_gettime.S @@ -34,14 +34,15 @@ __kernel_clock_gettime: tmll %r4,0x0001 /* pending update ? loop */ jnz 0b stck 48(%r15) /* Store TOD clock */ + lgf %r2,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */ + lg %r0,__VDSO_XTIME_SEC(%r5) /* tk->xtime_sec */ + alg %r0,__VDSO_WTOM_SEC(%r5) /* + wall_to_monotonic.sec */ lg %r1,48(%r15) sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ - msgf %r1,__VDSO_NTP_MULT(%r5) /* * NTP adjustment */ - srlg %r1,%r1,12 /* cyc2ns(clock,cycle_delta) */ - alg %r1,__VDSO_XTIME_NSEC(%r5) /* + xtime */ - lg %r0,__VDSO_XTIME_SEC(%r5) - alg %r1,__VDSO_WTOM_NSEC(%r5) /* + wall_to_monotonic */ - alg %r0,__VDSO_WTOM_SEC(%r5) + msgf %r1,__VDSO_TK_MULT(%r5) /* * tk->mult */ + alg %r1,__VDSO_XTIME_NSEC(%r5) /* + tk->xtime_nsec */ + alg %r1,__VDSO_WTOM_NSEC(%r5) /* + wall_to_monotonic.nsec */ + srlg %r1,%r1,0(%r2) /* >> tk->shift */ clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */ jne 0b larl %r5,13f @@ -62,12 +63,13 @@ __kernel_clock_gettime: tmll %r4,0x0001 /* pending update ? loop */ jnz 5b stck 48(%r15) /* Store TOD clock */ + lgf %r2,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */ lg %r1,48(%r15) sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ - msgf %r1,__VDSO_NTP_MULT(%r5) /* * NTP adjustment */ - srlg %r1,%r1,12 /* cyc2ns(clock,cycle_delta) */ - alg %r1,__VDSO_XTIME_NSEC(%r5) /* + xtime */ - lg %r0,__VDSO_XTIME_SEC(%r5) + msgf %r1,__VDSO_TK_MULT(%r5) /* * tk->mult */ + alg %r1,__VDSO_XTIME_NSEC(%r5) /* + tk->xtime_nsec */ + srlg %r1,%r1,0(%r2) /* >> tk->shift */ + lg %r0,__VDSO_XTIME_SEC(%r5) /* tk->xtime_sec */ clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */ jne 5b larl %r5,13f diff --git a/arch/s390/kernel/vdso64/gettimeofday.S b/arch/s390/kernel/vdso64/gettimeofday.S index 36ee674722ec..d0860d1d0ccc 100644 --- a/arch/s390/kernel/vdso64/gettimeofday.S +++ b/arch/s390/kernel/vdso64/gettimeofday.S @@ -31,12 +31,13 @@ __kernel_gettimeofday: stck 48(%r15) /* Store TOD clock */ lg %r1,48(%r15) sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ - msgf %r1,__VDSO_NTP_MULT(%r5) /* * NTP adjustment */ - srlg %r1,%r1,12 /* cyc2ns(clock,cycle_delta) */ - alg %r1,__VDSO_XTIME_NSEC(%r5) /* + xtime.tv_nsec */ - lg %r0,__VDSO_XTIME_SEC(%r5) /* xtime.tv_sec */ + msgf %r1,__VDSO_TK_MULT(%r5) /* * tk->mult */ + alg %r1,__VDSO_XTIME_NSEC(%r5) /* + tk->xtime_nsec */ + lg %r0,__VDSO_XTIME_SEC(%r5) /* tk->xtime_sec */ clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */ jne 0b + lgf %r5,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */ + srlg %r1,%r1,0(%r5) /* >> tk->shift */ larl %r5,5f 2: clg %r1,0(%r5) jl 3f -- 2.34.1