The cntvct_ok variable has not had any external user since commit
c7a18100bdff ("lib/vdso: Avoid highres update if clocksource is not
VDSO capable").
It also only has one user in vdso.c, once during init, so rather than
having the caller of patch_vdso() initialize cntvct_ok, just call
cntvct_functional() directly and avoid the global variable entirely.
Signed-off-by: Rasmus Villemoes <[email protected]>
---
arch/arm/include/asm/vdso/vsyscall.h | 1 -
arch/arm/kernel/vdso.c | 10 +++-------
2 files changed, 3 insertions(+), 8 deletions(-)
diff --git a/arch/arm/include/asm/vdso/vsyscall.h b/arch/arm/include/asm/vdso/vsyscall.h
index 47e41ae8ccd0..9a2cd2673a82 100644
--- a/arch/arm/include/asm/vdso/vsyscall.h
+++ b/arch/arm/include/asm/vdso/vsyscall.h
@@ -9,7 +9,6 @@
#include <asm/cacheflush.h>
extern struct vdso_data *vdso_data;
-extern bool cntvct_ok;
/*
* Update the vDSO data page to keep in sync with kernel timekeeping.
diff --git a/arch/arm/kernel/vdso.c b/arch/arm/kernel/vdso.c
index f297d66a8a76..ba87ffc6f194 100644
--- a/arch/arm/kernel/vdso.c
+++ b/arch/arm/kernel/vdso.c
@@ -67,11 +67,9 @@ struct elfinfo {
char *dynstr; /* ptr to .dynstr section */
};
-/* Cached result of boot-time check for whether the arch timer exists,
- * and if so, whether the virtual counter is useable.
+/* Boot-time check for whether the arch timer exists, and if so,
+ * whether the virtual counter is useable.
*/
-bool cntvct_ok __ro_after_init;
-
static bool __init cntvct_functional(void)
{
struct device_node *np;
@@ -172,7 +170,7 @@ static void __init patch_vdso(void *ehdr)
* want programs to incur the slight additional overhead of
* dispatching through the VDSO only to fall back to syscalls.
*/
- if (!cntvct_ok) {
+ if (!cntvct_functional()) {
vdso_nullpatch_one(&einfo, "__vdso_gettimeofday");
vdso_nullpatch_one(&einfo, "__vdso_clock_gettime");
vdso_nullpatch_one(&einfo, "__vdso_clock_gettime64");
@@ -213,8 +211,6 @@ static int __init vdso_init(void)
vdso_total_pages = 1; /* for the data/vvar page */
vdso_total_pages += text_pages;
- cntvct_ok = cntvct_functional();
-
patch_vdso(vdso_start);
return 0;
--
2.40.1.1.g1c60b9335d
On 11/3/23 07:57, Rasmus Villemoes wrote:
> The cntvct_ok variable has not had any external user since commit
> c7a18100bdff ("lib/vdso: Avoid highres update if clocksource is not
> VDSO capable").
>
> It also only has one user in vdso.c, once during init, so rather than
> having the caller of patch_vdso() initialize cntvct_ok, just call
> cntvct_functional() directly and avoid the global variable entirely.
>
> Signed-off-by: Rasmus Villemoes <[email protected]>
Fine by me.
Reviewed-by: Vincenzo Frascino <[email protected]>
> ---
> arch/arm/include/asm/vdso/vsyscall.h | 1 -
> arch/arm/kernel/vdso.c | 10 +++-------
> 2 files changed, 3 insertions(+), 8 deletions(-)
>
> diff --git a/arch/arm/include/asm/vdso/vsyscall.h b/arch/arm/include/asm/vdso/vsyscall.h
> index 47e41ae8ccd0..9a2cd2673a82 100644
> --- a/arch/arm/include/asm/vdso/vsyscall.h
> +++ b/arch/arm/include/asm/vdso/vsyscall.h
> @@ -9,7 +9,6 @@
> #include <asm/cacheflush.h>
>
> extern struct vdso_data *vdso_data;
> -extern bool cntvct_ok;
>
> /*
> * Update the vDSO data page to keep in sync with kernel timekeeping.
> diff --git a/arch/arm/kernel/vdso.c b/arch/arm/kernel/vdso.c
> index f297d66a8a76..ba87ffc6f194 100644
> --- a/arch/arm/kernel/vdso.c
> +++ b/arch/arm/kernel/vdso.c
> @@ -67,11 +67,9 @@ struct elfinfo {
> char *dynstr; /* ptr to .dynstr section */
> };
>
> -/* Cached result of boot-time check for whether the arch timer exists,
> - * and if so, whether the virtual counter is useable.
> +/* Boot-time check for whether the arch timer exists, and if so,
> + * whether the virtual counter is useable.
> */
> -bool cntvct_ok __ro_after_init;
> -
> static bool __init cntvct_functional(void)
> {
> struct device_node *np;
> @@ -172,7 +170,7 @@ static void __init patch_vdso(void *ehdr)
> * want programs to incur the slight additional overhead of
> * dispatching through the VDSO only to fall back to syscalls.
> */
> - if (!cntvct_ok) {
> + if (!cntvct_functional()) {
> vdso_nullpatch_one(&einfo, "__vdso_gettimeofday");
> vdso_nullpatch_one(&einfo, "__vdso_clock_gettime");
> vdso_nullpatch_one(&einfo, "__vdso_clock_gettime64");
> @@ -213,8 +211,6 @@ static int __init vdso_init(void)
> vdso_total_pages = 1; /* for the data/vvar page */
> vdso_total_pages += text_pages;
>
> - cntvct_ok = cntvct_functional();
> -
> patch_vdso(vdso_start);
>
> return 0;
--
Regards,
Vincenzo