[PATCH v2 2/5] powerpc: Fix vDSO clock_getres()
Christophe Leroy
christophe.leroy at c-s.fr
Wed May 22 03:04:24 AEST 2019
Le 21/05/2019 à 18:08, Vincenzo Frascino a écrit :
> Hi Christophe,
>
> I did not see this patch in 5.2-rc1 and I was wondering if there is anything I
> can do to help with upstraming it.
As far as I can see you series still has status 'new' in patchwork so I
guess Michael didn't have time to look at it
(https://patchwork.ozlabs.org/patch/1086410/)
>
> Please let me know.
You series involves several arches, how do you plan to handle it ? Do
you expect each arch maintainer to take each patch independentely, or do
you expect acks from arch maintainers in order to merge the entire
series in a given tree (which one ?)
Christophe
>
> Thanks,
> Vincenzo
>
> On 23/04/2019 17:33, Christophe Leroy wrote:
>>
>>
>> Le 16/04/2019 à 18:14, Vincenzo Frascino a écrit :
>>> 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 at kernel.crashing.org>
>>> Cc: Paul Mackerras <paulus at samba.org>
>>> Cc: Michael Ellerman <mpe at ellerman.id.au>
>>> Signed-off-by: Vincenzo Frascino <vincenzo.frascino at arm.com>
>>
>> Reviewed-by: Christophe Leroy <christophe.leroy at c-s.fr>
>>
>>> ---
>>> 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 | 7 +++++--
>>> arch/powerpc/kernel/vdso64/gettimeofday.S | 7 +++++--
>>> 5 files changed, 14 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
>>> index bbc06bd72b1f..4333b9a473dc 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; /* Wall to monotonic clock nsec */
>>> __s64 wtom_clock_sec; /* Wall to monotonic clock sec */
>>> struct timespec stamp_xtime; /* xtime as at tb_orig_stamp */
>>> + __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 afd516b572f8..2b5f9e83c610 100644
>>> --- a/arch/powerpc/kernel/vdso32/gettimeofday.S
>>> +++ b/arch/powerpc/kernel/vdso32/gettimeofday.S
>>> @@ -160,12 +160,15 @@ V_FUNCTION_BEGIN(__kernel_clock_getres)
>>> cror cr0*4+eq,cr0*4+eq,cr1*4+eq
>>> bne cr0,99f
>>>
>>> + mflr r12
>>> + .cfi_register lr,r12
>>> + bl __get_datapage at local
>>> + lwz r5,CLOCK_REALTIME_RES(r3)
>>> + mtlr r12
>>> li r3,0
>>> cmpli cr0,r4,0
>>> crclr cr0*4+so
>>> beqlr
>>> - lis r5,CLOCK_REALTIME_RES at h
>>> - ori r5,r5,CLOCK_REALTIME_RES at l
>>> stw r3,TSPC32_TV_SEC(r4)
>>> stw r5,TSPC32_TV_NSEC(r4)
>>> blr
>>> diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S
>>> index 1f324c28705b..f07730f73d5e 100644
>>> --- a/arch/powerpc/kernel/vdso64/gettimeofday.S
>>> +++ b/arch/powerpc/kernel/vdso64/gettimeofday.S
>>> @@ -190,12 +190,15 @@ V_FUNCTION_BEGIN(__kernel_clock_getres)
>>> cror cr0*4+eq,cr0*4+eq,cr1*4+eq
>>> bne cr0,99f
>>>
>>> + mflr r12
>>> + .cfi_register lr,r12
>>> + bl V_LOCAL_FUNC(__get_datapage)
>>> + lwz r5,CLOCK_REALTIME_RES(r3)
>>> + mtlr r12
>>> li r3,0
>>> cmpldi cr0,r4,0
>>> crclr cr0*4+so
>>> beqlr
>>> - lis r5,CLOCK_REALTIME_RES at h
>>> - ori r5,r5,CLOCK_REALTIME_RES at l
>>> std r3,TSPC64_TV_SEC(r4)
>>> std r5,TSPC64_TV_NSEC(r4)
>>> blr
>>>
>
More information about the Linuxppc-dev
mailing list