Re: [PATCH v7 04/25] arm64: Substitute gettimeofday with C implementation

[Catalin Marinas <catalin.marinas@xxxxxxx>]

On Fri, Jun 21, 2019 at 10:52:31AM +0100, Vincenzo Frascino wrote:
> diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
> index 947e39896e28..9e4b7ccbab2f 100644
> --- a/arch/arm64/kernel/asm-offsets.c
> +++ b/arch/arm64/kernel/asm-offsets.c
> @@ -25,13 +25,13 @@
>  #include <linux/kvm_host.h>
>  #include <linux/preempt.h>
>  #include <linux/suspend.h>
> +#include <vdso/datapage.h>
>  #include <asm/cpufeature.h>
>  #include <asm/fixmap.h>
>  #include <asm/thread_info.h>
>  #include <asm/memory.h>
>  #include <asm/smp_plat.h>
>  #include <asm/suspend.h>
> -#include <asm/vdso_datapage.h>
>  #include <linux/kbuild.h>
>  #include <linux/arm-smccc.h>
>  
> @@ -100,17 +100,28 @@ int main(void)
>    DEFINE(CLOCK_COARSE_RES,	LOW_RES_NSEC);
>    DEFINE(NSEC_PER_SEC,		NSEC_PER_SEC);
>    BLANK();
> -  DEFINE(VDSO_CS_CYCLE_LAST,	offsetof(struct vdso_data, cs_cycle_last));
> -  DEFINE(VDSO_RAW_TIME_SEC,	offsetof(struct vdso_data, raw_time_sec));
> -  DEFINE(VDSO_XTIME_CLK_SEC,	offsetof(struct vdso_data, xtime_clock_sec));
> -  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_WTM_CLK_SEC,	offsetof(struct vdso_data, wtm_clock_sec));
> -  DEFINE(VDSO_TB_SEQ_COUNT,	offsetof(struct vdso_data, tb_seq_count));
> -  DEFINE(VDSO_CS_MONO_MULT,	offsetof(struct vdso_data, cs_mono_mult));
> -  DEFINE(VDSO_CS_SHIFT,		offsetof(struct vdso_data, cs_shift));
> +  DEFINE(VDSO_SEQ,		offsetof(struct vdso_data, seq));
> +  DEFINE(VDSO_CLK_MODE,		offsetof(struct vdso_data, clock_mode));
> +  DEFINE(VDSO_CYCLE_LAST,	offsetof(struct vdso_data, cycle_last));
> +  DEFINE(VDSO_MASK,		offsetof(struct vdso_data, mask));
> +  DEFINE(VDSO_MULT,		offsetof(struct vdso_data, mult));
> +  DEFINE(VDSO_SHIFT,		offsetof(struct vdso_data, shift));
> +  DEFINE(VDSO_REALTIME_SEC,	offsetof(struct vdso_data, basetime[CLOCK_REALTIME].sec));
> +  DEFINE(VDSO_REALTIME_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_REALTIME].nsec));
> +  DEFINE(VDSO_MONO_SEC,		offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC].sec));
> +  DEFINE(VDSO_MONO_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC].nsec));
> +  DEFINE(VDSO_MONO_RAW_SEC,	offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC_RAW].sec));
> +  DEFINE(VDSO_MONO_RAW_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC_RAW].nsec));
> +  DEFINE(VDSO_BOOTTIME_SEC,	offsetof(struct vdso_data, basetime[CLOCK_BOOTTIME].sec));
> +  DEFINE(VDSO_BOOTTIME_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_BOOTTIME].nsec));
> +  DEFINE(VDSO_TAI_SEC,		offsetof(struct vdso_data, basetime[CLOCK_TAI].sec));
> +  DEFINE(VDSO_TAI_NSEC,		offsetof(struct vdso_data, basetime[CLOCK_TAI].nsec));
> +  DEFINE(VDSO_RT_COARSE_SEC,	offsetof(struct vdso_data, basetime[CLOCK_REALTIME_COARSE].sec));
> +  DEFINE(VDSO_RT_COARSE_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_REALTIME_COARSE].nsec));
> +  DEFINE(VDSO_MONO_COARSE_SEC,	offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC_COARSE].sec));
> +  DEFINE(VDSO_MONO_COARSE_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC_COARSE].nsec));
>    DEFINE(VDSO_TZ_MINWEST,	offsetof(struct vdso_data, tz_minuteswest));
> -  DEFINE(VDSO_USE_SYSCALL,	offsetof(struct vdso_data, use_syscall));
> +  DEFINE(VDSO_TZ_DSTTIME,	offsetof(struct vdso_data, tz_dsttime));
>    BLANK();
>    DEFINE(TVAL_TV_SEC,		offsetof(struct timeval, tv_sec));
>    DEFINE(TSPEC_TV_SEC,		offsetof(struct timespec, tv_sec));

Now that we are moving this to C, do we actually need the asm-offsets?
If not, here's a clean-up patch:

---------------8<--------------------------------------
>From 7e818178a8b225b522fe547cf00ba8508d4cdcf0 Mon Sep 17 00:00:00 2001
From: Catalin Marinas <catalin.marinas@xxxxxxx>
Date: Mon, 24 Jun 2019 14:12:48 +0100
Subject: [PATCH] arm64: vdso: Remove unnecessary asm-offsets.c definitions

Since the VDSO code is moving to C from assembly, there is no need to
define and maintain the corresponding asm offsets.

Fixes: 28b1a824a4f4 ("arm64: vdso: Substitute gettimeofday() with C implementation")
Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx>
---
 arch/arm64/kernel/asm-offsets.c | 39 ---------------------------------
 1 file changed, 39 deletions(-)

diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index e6f7409a78a4..214685760e1c 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -14,7 +14,6 @@
 #include <linux/kvm_host.h>
 #include <linux/preempt.h>
 #include <linux/suspend.h>
-#include <vdso/datapage.h>
 #include <asm/cpufeature.h>
 #include <asm/fixmap.h>
 #include <asm/thread_info.h>
@@ -86,44 +85,6 @@ int main(void)
   BLANK();
   DEFINE(PREEMPT_DISABLE_OFFSET, PREEMPT_DISABLE_OFFSET);
   BLANK();
-  DEFINE(CLOCK_REALTIME,	CLOCK_REALTIME);
-  DEFINE(CLOCK_MONOTONIC,	CLOCK_MONOTONIC);
-  DEFINE(CLOCK_MONOTONIC_RAW,	CLOCK_MONOTONIC_RAW);
-  DEFINE(CLOCK_REALTIME_RES,	offsetof(struct vdso_data, hrtimer_res));
-  DEFINE(CLOCK_REALTIME_COARSE,	CLOCK_REALTIME_COARSE);
-  DEFINE(CLOCK_MONOTONIC_COARSE,CLOCK_MONOTONIC_COARSE);
-  DEFINE(CLOCK_COARSE_RES,	LOW_RES_NSEC);
-  DEFINE(NSEC_PER_SEC,		NSEC_PER_SEC);
-  BLANK();
-  DEFINE(VDSO_SEQ,		offsetof(struct vdso_data, seq));
-  DEFINE(VDSO_CLK_MODE,		offsetof(struct vdso_data, clock_mode));
-  DEFINE(VDSO_CYCLE_LAST,	offsetof(struct vdso_data, cycle_last));
-  DEFINE(VDSO_MASK,		offsetof(struct vdso_data, mask));
-  DEFINE(VDSO_MULT,		offsetof(struct vdso_data, mult));
-  DEFINE(VDSO_SHIFT,		offsetof(struct vdso_data, shift));
-  DEFINE(VDSO_REALTIME_SEC,	offsetof(struct vdso_data, basetime[CLOCK_REALTIME].sec));
-  DEFINE(VDSO_REALTIME_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_REALTIME].nsec));
-  DEFINE(VDSO_MONO_SEC,		offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC].sec));
-  DEFINE(VDSO_MONO_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC].nsec));
-  DEFINE(VDSO_MONO_RAW_SEC,	offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC_RAW].sec));
-  DEFINE(VDSO_MONO_RAW_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC_RAW].nsec));
-  DEFINE(VDSO_BOOTTIME_SEC,	offsetof(struct vdso_data, basetime[CLOCK_BOOTTIME].sec));
-  DEFINE(VDSO_BOOTTIME_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_BOOTTIME].nsec));
-  DEFINE(VDSO_TAI_SEC,		offsetof(struct vdso_data, basetime[CLOCK_TAI].sec));
-  DEFINE(VDSO_TAI_NSEC,		offsetof(struct vdso_data, basetime[CLOCK_TAI].nsec));
-  DEFINE(VDSO_RT_COARSE_SEC,	offsetof(struct vdso_data, basetime[CLOCK_REALTIME_COARSE].sec));
-  DEFINE(VDSO_RT_COARSE_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_REALTIME_COARSE].nsec));
-  DEFINE(VDSO_MONO_COARSE_SEC,	offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC_COARSE].sec));
-  DEFINE(VDSO_MONO_COARSE_NSEC,	offsetof(struct vdso_data, basetime[CLOCK_MONOTONIC_COARSE].nsec));
-  DEFINE(VDSO_TZ_MINWEST,	offsetof(struct vdso_data, tz_minuteswest));
-  DEFINE(VDSO_TZ_DSTTIME,	offsetof(struct vdso_data, tz_dsttime));
-  BLANK();
-  DEFINE(TVAL_TV_SEC,		offsetof(struct timeval, tv_sec));
-  DEFINE(TSPEC_TV_SEC,		offsetof(struct timespec, tv_sec));
-  BLANK();
-  DEFINE(TZ_MINWEST,		offsetof(struct timezone, tz_minuteswest));
-  DEFINE(TZ_DSTTIME,		offsetof(struct timezone, tz_dsttime));
-  BLANK();
   DEFINE(CPU_BOOT_STACK,	offsetof(struct secondary_data, stack));
   DEFINE(CPU_BOOT_TASK,		offsetof(struct secondary_data, task));
   BLANK();