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 <schwidefsky@de.ibm.com>

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 314fced..5877e71 100644 (file)
--- 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 a73eb2e..bc9746a 100644 (file)
--- 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 2416138..496116c 100644 (file)
--- 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 064c308..60a508a 100644 (file)
--- 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 b2224e0..5be8e47 100644 (file)
--- 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 2d36331..fd621a9 100644 (file)
--- 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 d46c95e..0add107 100644 (file)
--- 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 36ee674..d0860d1 100644 (file)
--- 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