From b7eacb59cd7fb5e98852186e485c0c865f862645 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Fri, 29 Aug 2014 12:31:45 +0200 Subject: [PATCH] s390/vdso: add vdso support for coarse clocks Add CLOCK_REALTIME_COARSE and CLOCK_MONOTONIC_COARSE optimization to the 64-bit and 31-bit vdso. Signed-off-by: Martin Schwidefsky --- arch/s390/include/asm/vdso.h | 18 +++++++++++------- arch/s390/kernel/asm-offsets.c | 7 +++++++ arch/s390/kernel/time.c | 13 +++++++++++++ arch/s390/kernel/vdso32/clock_getres.S | 11 +++++++++-- arch/s390/kernel/vdso32/clock_gettime.S | 24 ++++++++++++++++++++++++ arch/s390/kernel/vdso64/clock_getres.S | 8 +++++++- arch/s390/kernel/vdso64/clock_gettime.S | 24 ++++++++++++++++++++++++ 7 files changed, 95 insertions(+), 10 deletions(-) diff --git a/arch/s390/include/asm/vdso.h b/arch/s390/include/asm/vdso.h index bc9746a7d47c..a62526d09201 100644 --- a/arch/s390/include/asm/vdso.h +++ b/arch/s390/include/asm/vdso.h @@ -22,13 +22,17 @@ struct vdso_data { __u64 xtime_tod_stamp; /* TOD clock for xtime 0x08 */ __u64 xtime_clock_sec; /* Kernel time 0x10 */ __u64 xtime_clock_nsec; /* 0x18 */ - __u64 wtom_clock_sec; /* Wall to monotonic clock 0x20 */ - __u64 wtom_clock_nsec; /* 0x28 */ - __u32 tz_minuteswest; /* Minutes west of Greenwich 0x30 */ - __u32 tz_dsttime; /* Type of dst correction 0x34 */ - __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 */ + __u64 xtime_coarse_sec; /* Coarse kernel time 0x20 */ + __u64 xtime_coarse_nsec; /* 0x28 */ + __u64 wtom_clock_sec; /* Wall to monotonic clock 0x30 */ + __u64 wtom_clock_nsec; /* 0x38 */ + __u64 wtom_coarse_sec; /* Coarse wall to monotonic 0x40 */ + __u64 wtom_coarse_nsec; /* 0x48 */ + __u32 tz_minuteswest; /* Minutes west of Greenwich 0x50 */ + __u32 tz_dsttime; /* Type of dst correction 0x54 */ + __u32 ectg_available; /* ECTG instruction present 0x58 */ + __u32 tk_mult; /* Mult. used for xtime_nsec 0x5c */ + __u32 tk_shift; /* Shift used for xtime_nsec 0x60 */ }; struct vdso_per_cpu_data { diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c index afe1715a4eb7..3e9e479d9b49 100644 --- a/arch/s390/kernel/asm-offsets.c +++ b/arch/s390/kernel/asm-offsets.c @@ -62,8 +62,12 @@ int main(void) DEFINE(__VDSO_XTIME_STAMP, offsetof(struct vdso_data, xtime_tod_stamp)); DEFINE(__VDSO_XTIME_SEC, offsetof(struct vdso_data, xtime_clock_sec)); DEFINE(__VDSO_XTIME_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_WTOM_SEC, offsetof(struct vdso_data, wtom_clock_sec)); DEFINE(__VDSO_WTOM_NSEC, offsetof(struct vdso_data, wtom_clock_nsec)); + DEFINE(__VDSO_WTOM_CRS_SEC, offsetof(struct vdso_data, wtom_coarse_sec)); + DEFINE(__VDSO_WTOM_CRS_NSEC, offsetof(struct vdso_data, wtom_coarse_nsec)); DEFINE(__VDSO_TIMEZONE, offsetof(struct vdso_data, tz_minuteswest)); DEFINE(__VDSO_ECTG_OK, offsetof(struct vdso_data, ectg_available)); DEFINE(__VDSO_TK_MULT, offsetof(struct vdso_data, tk_mult)); @@ -73,8 +77,11 @@ int main(void) /* constants used by the vdso */ DEFINE(__CLOCK_REALTIME, CLOCK_REALTIME); DEFINE(__CLOCK_MONOTONIC, CLOCK_MONOTONIC); + DEFINE(__CLOCK_REALTIME_COARSE, CLOCK_REALTIME_COARSE); + DEFINE(__CLOCK_MONOTONIC_COARSE, CLOCK_MONOTONIC_COARSE); DEFINE(__CLOCK_THREAD_CPUTIME_ID, CLOCK_THREAD_CPUTIME_ID); DEFINE(__CLOCK_REALTIME_RES, MONOTONIC_RES_NSEC); + DEFINE(__CLOCK_COARSE_RES, LOW_RES_NSEC); BLANK(); /* idle data offsets */ DEFINE(__CLOCK_IDLE_ENTER, offsetof(struct s390_idle_data, clock_idle_enter)); diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c index 4cef607f3711..69e980de0f62 100644 --- a/arch/s390/kernel/time.c +++ b/arch/s390/kernel/time.c @@ -232,6 +232,19 @@ void update_vsyscall(struct timekeeper *tk) vdso_data->wtom_clock_nsec -= nsecps; vdso_data->wtom_clock_sec++; } + + vdso_data->xtime_coarse_sec = tk->xtime_sec; + vdso_data->xtime_coarse_nsec = + (long)(tk->tkr.xtime_nsec >> tk->tkr.shift); + vdso_data->wtom_coarse_sec = + vdso_data->xtime_coarse_sec + tk->wall_to_monotonic.tv_sec; + vdso_data->wtom_coarse_nsec = + vdso_data->xtime_coarse_nsec + tk->wall_to_monotonic.tv_nsec; + while (vdso_data->wtom_coarse_nsec >= NSEC_PER_SEC) { + vdso_data->wtom_coarse_nsec -= NSEC_PER_SEC; + vdso_data->wtom_coarse_sec++; + } + vdso_data->tk_mult = tk->tkr.mult; vdso_data->tk_shift = tk->tkr.shift; smp_wmb(); diff --git a/arch/s390/kernel/vdso32/clock_getres.S b/arch/s390/kernel/vdso32/clock_getres.S index 36aaa25d05da..eca3f001f081 100644 --- a/arch/s390/kernel/vdso32/clock_getres.S +++ b/arch/s390/kernel/vdso32/clock_getres.S @@ -19,14 +19,20 @@ .type __kernel_clock_getres,@function __kernel_clock_getres: .cfi_startproc + basr %r1,0 + la %r1,4f-.(%r1) chi %r2,__CLOCK_REALTIME je 0f chi %r2,__CLOCK_MONOTONIC + je 0f + la %r1,5f-4f(%r1) + chi %r2,__CLOCK_REALTIME_COARSE + je 0f + chi %r2,__CLOCK_MONOTONIC_COARSE jne 3f 0: ltr %r3,%r3 jz 2f /* res == NULL */ - basr %r1,0 -1: l %r0,4f-1b(%r1) +1: l %r0,0(%r1) xc 0(4,%r3),0(%r3) /* set tp->tv_sec to zero */ st %r0,4(%r3) /* store tp->tv_usec */ 2: lhi %r2,0 @@ -35,5 +41,6 @@ __kernel_clock_getres: svc 0 br %r14 4: .long __CLOCK_REALTIME_RES +5: .long __CLOCK_COARSE_RES .cfi_endproc .size __kernel_clock_getres,.-__kernel_clock_getres diff --git a/arch/s390/kernel/vdso32/clock_gettime.S b/arch/s390/kernel/vdso32/clock_gettime.S index 4e20a9365bb7..48c2206a3956 100644 --- a/arch/s390/kernel/vdso32/clock_gettime.S +++ b/arch/s390/kernel/vdso32/clock_gettime.S @@ -21,8 +21,12 @@ __kernel_clock_gettime: .cfi_startproc basr %r5,0 0: al %r5,21f-0b(%r5) /* get &_vdso_data */ + chi %r2,__CLOCK_REALTIME_COARSE + je 10f chi %r2,__CLOCK_REALTIME je 11f + chi %r2,__CLOCK_MONOTONIC_COARSE + je 9f chi %r2,__CLOCK_MONOTONIC jne 19f @@ -68,6 +72,26 @@ __kernel_clock_gettime: lhi %r2,0 br %r14 + /* CLOCK_MONOTONIC_COARSE */ +9: l %r4,__VDSO_UPD_COUNT+4(%r5) /* load update counter */ + tml %r4,0x0001 /* pending update ? loop */ + jnz 9b + l %r2,__VDSO_WTOM_CRS_SEC+4(%r5) + l %r1,__VDSO_WTOM_CRS_NSEC+4(%r5) + cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */ + jne 9b + j 8b + + /* CLOCK_REALTIME_COARSE */ +10: l %r4,__VDSO_UPD_COUNT+4(%r5) /* load update counter */ + tml %r4,0x0001 /* pending update ? loop */ + jnz 10b + l %r2,__VDSO_XTIME_CRS_SEC+4(%r5) + l %r1,__VDSO_XTIME_CRS_NSEC+4(%r5) + cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */ + jne 10b + j 17f + /* CLOCK_REALTIME */ 11: l %r4,__VDSO_UPD_COUNT+4(%r5) /* load update counter */ tml %r4,0x0001 /* pending update ? loop */ diff --git a/arch/s390/kernel/vdso64/clock_getres.S b/arch/s390/kernel/vdso64/clock_getres.S index 34deba7c7ed1..c8513deb8c66 100644 --- a/arch/s390/kernel/vdso64/clock_getres.S +++ b/arch/s390/kernel/vdso64/clock_getres.S @@ -19,6 +19,12 @@ .type __kernel_clock_getres,@function __kernel_clock_getres: .cfi_startproc + larl %r1,4f + cghi %r2,__CLOCK_REALTIME_COARSE + je 0f + cghi %r2,__CLOCK_MONOTONIC_COARSE + je 0f + larl %r1,3f cghi %r2,__CLOCK_REALTIME je 0f cghi %r2,__CLOCK_MONOTONIC @@ -32,7 +38,6 @@ __kernel_clock_getres: jz 2f 0: ltgr %r3,%r3 jz 1f /* res == NULL */ - larl %r1,3f lg %r0,0(%r1) xc 0(8,%r3),0(%r3) /* set tp->tv_sec to zero */ stg %r0,8(%r3) /* store tp->tv_usec */ @@ -42,5 +47,6 @@ __kernel_clock_getres: svc 0 br %r14 3: .quad __CLOCK_REALTIME_RES +4: .quad __CLOCK_COARSE_RES .cfi_endproc .size __kernel_clock_getres,.-__kernel_clock_getres diff --git a/arch/s390/kernel/vdso64/clock_gettime.S b/arch/s390/kernel/vdso64/clock_gettime.S index 4add40b78ed5..9d9761f8e110 100644 --- a/arch/s390/kernel/vdso64/clock_gettime.S +++ b/arch/s390/kernel/vdso64/clock_gettime.S @@ -20,12 +20,16 @@ __kernel_clock_gettime: .cfi_startproc larl %r5,_vdso_data + cghi %r2,__CLOCK_REALTIME_COARSE + je 4f cghi %r2,__CLOCK_REALTIME je 5f cghi %r2,__CLOCK_THREAD_CPUTIME_ID je 9f cghi %r2,-2 /* Per-thread CPUCLOCK with PID=0, VIRT=1 */ je 9f + cghi %r2,__CLOCK_MONOTONIC_COARSE + je 3f cghi %r2,__CLOCK_MONOTONIC jne 12f @@ -54,6 +58,26 @@ __kernel_clock_gettime: lghi %r2,0 br %r14 + /* CLOCK_MONOTONIC_COARSE */ +3: lg %r4,__VDSO_UPD_COUNT(%r5) /* load update counter */ + tmll %r4,0x0001 /* pending update ? loop */ + jnz 3b + lg %r0,__VDSO_WTOM_CRS_SEC(%r5) + lg %r1,__VDSO_WTOM_CRS_NSEC(%r5) + clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */ + jne 3b + j 2b + + /* CLOCK_REALTIME_COARSE */ +4: lg %r4,__VDSO_UPD_COUNT(%r5) /* load update counter */ + tmll %r4,0x0001 /* pending update ? loop */ + jnz 4b + lg %r0,__VDSO_XTIME_CRS_SEC(%r5) + lg %r1,__VDSO_XTIME_CRS_NSEC(%r5) + clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */ + jne 4b + j 7f + /* CLOCK_REALTIME */ 5: lg %r4,__VDSO_UPD_COUNT(%r5) /* load update counter */ tmll %r4,0x0001 /* pending update ? loop */