clock_getres in the vDSO library has to preserve the same behaviour
of posix_get_hrtimer_res().
In particular, posix_get_hrtimer_res() does:
sec = 0;
ns = hrtimer_resolution;
and hrtimer_resolution depends on the enablement of the high
resolution timers that can happen either at compile or at run time.
Fix the powerpc vdso implementation of clock_getres keeping a copy of
hrtimer_resolution in vdso data and using that directly.
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
---
arch/powerpc/include/asm/vdso_datapage.h | 2 ++
arch/powerpc/kernel/asm-offsets.c | 2 +-
arch/powerpc/kernel/time.c | 1 +
arch/powerpc/kernel/vdso32/gettimeofday.S | 22 +++++++++++++++-------
arch/powerpc/kernel/vdso64/gettimeofday.S | 22 +++++++++++++++-------
5 files changed, 34 insertions(+), 15 deletions(-)
diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
index 1afe90ade595..4ae43fc77fe9 100644
--- a/arch/powerpc/include/asm/vdso_datapage.h
+++ b/arch/powerpc/include/asm/vdso_datapage.h
@@ -86,6 +86,7 @@ struct vdso_data {
__s32 wtom_clock_nsec;
struct timespec stamp_xtime; /* xtime as at tb_orig_stamp */
__u32 stamp_sec_fraction; /* fractional seconds of stamp_xtime */
+ __u32 hrtimer_res; /* hrtimer resolution */
__u32 syscall_map_64[SYSCALL_MAP_SIZE]; /* map of syscalls */
__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
};
@@ -107,6 +108,7 @@ struct vdso_data {
__s32 wtom_clock_nsec;
struct timespec stamp_xtime; /* xtime as at tb_orig_stamp */
__u32 stamp_sec_fraction; /* fractional seconds of stamp_xtime */
+ __u32 hrtimer_res; /* hrtimer resolution */
__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
__u32 dcache_block_size; /* L1 d-cache block size */
__u32 icache_block_size; /* L1 i-cache block size */
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 86a61e5f8285..52e4b98a8492 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -383,6 +383,7 @@ int main(void)
OFFSET(WTOM_CLOCK_NSEC, vdso_data, wtom_clock_nsec);
OFFSET(STAMP_XTIME, vdso_data, stamp_xtime);
OFFSET(STAMP_SEC_FRAC, vdso_data, stamp_sec_fraction);
+ OFFSET(CLOCK_REALTIME_RES, vdso_data, hrtimer_res);
OFFSET(CFG_ICACHE_BLOCKSZ, vdso_data, icache_block_size);
OFFSET(CFG_DCACHE_BLOCKSZ, vdso_data, dcache_block_size);
OFFSET(CFG_ICACHE_LOGBLOCKSZ, vdso_data, icache_log_block_size);
@@ -413,7 +414,6 @@ int main(void)
DEFINE(CLOCK_REALTIME_COARSE, CLOCK_REALTIME_COARSE);
DEFINE(CLOCK_MONOTONIC_COARSE, CLOCK_MONOTONIC_COARSE);
DEFINE(NSEC_PER_SEC, NSEC_PER_SEC);
- DEFINE(CLOCK_REALTIME_RES, MONOTONIC_RES_NSEC);
#ifdef CONFIG_BUG
DEFINE(BUG_ENTRY_SIZE, sizeof(struct bug_entry));
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index bc0503ef9c9c..62c04a6746d8 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -955,6 +955,7 @@ void update_vsyscall(struct timekeeper *tk)
vdso_data->wtom_clock_nsec = tk->wall_to_monotonic.tv_nsec;
vdso_data->stamp_xtime = xt;
vdso_data->stamp_sec_fraction = frac_sec;
+ vdso_data->hrtimer_res = hrtimer_resolution;
smp_wmb();
++(vdso_data->tb_update_count);
}
diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S
index 1e0bc5955a40..b21630079496 100644
--- a/arch/powerpc/kernel/vdso32/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso32/gettimeofday.S
@@ -160,14 +160,21 @@ V_FUNCTION_BEGIN(__kernel_clock_getres)
cror cr0*4+eq,cr0*4+eq,cr1*4+eq
bne cr0,99f
- li r3,0
- cmpli cr0,r4,0
+ mflr r12
+ .cfi_register lr,r12
+ mr r11,r4
+ bl __get_datapage@local
+ lwz r5,CLOCK_REALTIME_RES(r3)
+ li r4,0
+ cmplwi r11,0 /* check if res is NULL */
+ beq 1f
+
+ stw r4,TSPC32_TV_SEC(r11)
+ stw r5,TSPC32_TV_NSEC(r11)
+
+1: mtlr r12
crclr cr0*4+so
- beqlr
- lis r5,CLOCK_REALTIME_RES@h
- ori r5,r5,CLOCK_REALTIME_RES@l
- stw r3,TSPC32_TV_SEC(r4)
- stw r5,TSPC32_TV_NSEC(r4)
+ li r3,0
blr
/*
@@ -175,6 +182,7 @@ V_FUNCTION_BEGIN(__kernel_clock_getres)
*/
99:
li r0,__NR_clock_getres
+ .cfi_restore lr
sc
blr
.cfi_endproc
diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S
index a4ed9edfd5f0..a7e49bddd475 100644
--- a/arch/powerpc/kernel/vdso64/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso64/gettimeofday.S
@@ -190,14 +190,21 @@ V_FUNCTION_BEGIN(__kernel_clock_getres)
cror cr0*4+eq,cr0*4+eq,cr1*4+eq
bne cr0,99f
- li r3,0
- cmpldi cr0,r4,0
+ mflr r12
+ .cfi_register lr,r12
+ mr r11, r4
+ bl V_LOCAL_FUNC(__get_datapage)
+ lwz r5,CLOCK_REALTIME_RES(r3)
+ li r4,0
+ cmpldi r11,0 /* check if res is NULL */
+ beq 1f
+
+ std r4,TSPC64_TV_SEC(r11)
+ std r5,TSPC64_TV_NSEC(r11)
+
+1: mtlr r12
crclr cr0*4+so
- beqlr
- lis r5,CLOCK_REALTIME_RES@h
- ori r5,r5,CLOCK_REALTIME_RES@l
- std r3,TSPC64_TV_SEC(r4)
- std r5,TSPC64_TV_NSEC(r4)
+ li r3,0
blr
/*
@@ -205,6 +212,7 @@ V_FUNCTION_BEGIN(__kernel_clock_getres)
*/
99:
li r0,__NR_clock_getres
+ .cfi_restore lr
sc
blr
.cfi_endproc
--
2.21.0
