summaryrefslogtreecommitdiff
path: root/arch/arm64/kernel/vdso.c
diff options
context:
space:
mode:
authorVincenzo Frascino <vincenzo.frascino@arm.com>2019-06-21 10:52:31 +0100
committerThomas Gleixner <tglx@linutronix.de>2019-06-22 21:21:06 +0200
commit28b1a824a4f44da46983cd2c3249f910bd4b797b (patch)
tree9e763b48cb41f168181b325db4939d328567bac6 /arch/arm64/kernel/vdso.c
parent44f57d788e7deecb504843534081d3449c2eede9 (diff)
downloadlwn-28b1a824a4f44da46983cd2c3249f910bd4b797b.tar.gz
lwn-28b1a824a4f44da46983cd2c3249f910bd4b797b.zip
arm64: vdso: Substitute gettimeofday() with C implementation
To take advantage of the commonly defined vdso interface for gettimeofday() the architectural code requires an adaptation. Re-implement the gettimeofday VDSO in C in order to use lib/vdso. With the new implementation arm64 gains support for CLOCK_BOOTTIME and CLOCK_TAI. [ tglx: Reformatted the function line breaks ] Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Shijith Thotton <sthotton@marvell.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Cc: linux-arch@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-mips@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@armlinux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Burton <paul.burton@mips.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Mark Salyzyn <salyzyn@android.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Huw Davies <huw@codeweavers.com> Link: https://lkml.kernel.org/r/20190621095252.32307-5-vincenzo.frascino@arm.com
Diffstat (limited to 'arch/arm64/kernel/vdso.c')
-rw-r--r--arch/arm64/kernel/vdso.c51
1 files changed, 5 insertions, 46 deletions
diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
index 663b166241d0..478ec865a413 100644
--- a/arch/arm64/kernel/vdso.c
+++ b/arch/arm64/kernel/vdso.c
@@ -20,11 +20,13 @@
#include <linux/slab.h>
#include <linux/timekeeper_internal.h>
#include <linux/vmalloc.h>
+#include <vdso/datapage.h>
+#include <vdso/helpers.h>
+#include <vdso/vsyscall.h>
#include <asm/cacheflush.h>
#include <asm/signal32.h>
#include <asm/vdso.h>
-#include <asm/vdso_datapage.h>
extern char vdso_start[], vdso_end[];
static unsigned long vdso_pages __ro_after_init;
@@ -33,10 +35,10 @@ static unsigned long vdso_pages __ro_after_init;
* The vDSO data page.
*/
static union {
- struct vdso_data data;
+ struct vdso_data data[CS_BASES];
u8 page[PAGE_SIZE];
} vdso_data_store __page_aligned_data;
-struct vdso_data *vdso_data = &vdso_data_store.data;
+struct vdso_data *vdso_data = vdso_data_store.data;
#ifdef CONFIG_COMPAT
/*
@@ -269,46 +271,3 @@ up_fail:
up_write(&mm->mmap_sem);
return PTR_ERR(ret);
}
-
-/*
- * Update the vDSO data page to keep in sync with kernel timekeeping.
- */
-void update_vsyscall(struct timekeeper *tk)
-{
- u32 use_syscall = !tk->tkr_mono.clock->archdata.vdso_direct;
-
- ++vdso_data->tb_seq_count;
- smp_wmb();
-
- vdso_data->use_syscall = use_syscall;
- vdso_data->xtime_coarse_sec = tk->xtime_sec;
- vdso_data->xtime_coarse_nsec = tk->tkr_mono.xtime_nsec >>
- tk->tkr_mono.shift;
- vdso_data->wtm_clock_sec = tk->wall_to_monotonic.tv_sec;
- vdso_data->wtm_clock_nsec = tk->wall_to_monotonic.tv_nsec;
-
- /* Read without the seqlock held by clock_getres() */
- WRITE_ONCE(vdso_data->hrtimer_res, hrtimer_resolution);
-
- if (!use_syscall) {
- /* tkr_mono.cycle_last == tkr_raw.cycle_last */
- vdso_data->cs_cycle_last = tk->tkr_mono.cycle_last;
- vdso_data->raw_time_sec = tk->raw_sec;
- vdso_data->raw_time_nsec = tk->tkr_raw.xtime_nsec;
- vdso_data->xtime_clock_sec = tk->xtime_sec;
- vdso_data->xtime_clock_nsec = tk->tkr_mono.xtime_nsec;
- vdso_data->cs_mono_mult = tk->tkr_mono.mult;
- vdso_data->cs_raw_mult = tk->tkr_raw.mult;
- /* tkr_mono.shift == tkr_raw.shift */
- vdso_data->cs_shift = tk->tkr_mono.shift;
- }
-
- smp_wmb();
- ++vdso_data->tb_seq_count;
-}
-
-void update_vsyscall_tz(void)
-{
- vdso_data->tz_minuteswest = sys_tz.tz_minuteswest;
- vdso_data->tz_dsttime = sys_tz.tz_dsttime;
-}