From: Christophe Leroy <christophe.leroy@c-s.fr>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Paul Mackerras <paulus@samba.org>,
Michael Ellerman <mpe@ellerman.id.au>,
nathanl@linux.ibm.com, arnd@arndb.de, tglx@linutronix.de,
vincenzo.frascino@arm.com, luto@kernel.org
Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org,
x86@kernel.org
Subject: [PATCH v5 3/6] lib/vdso: Allow architectures to provide the vdso data pointer
Date: Thu, 30 Jan 2020 16:08:37 +0000 (UTC) [thread overview]
Message-ID: <abf97996602ef07223fec30c005df78e5ed41b2e.1580399657.git.christophe.leroy@c-s.fr> (raw)
In-Reply-To: <cover.1580399657.git.christophe.leroy@c-s.fr>
On powerpc, __arch_get_vdso_data() clobbers the link register,
requiring the caller to save it.
As the parent function already has to set a stack frame and saves
the link register before calling the C vdso function, retriving the
vdso data pointer there is lighter.
Give architectures the opportunity to hand the vdso data pointer
to C vdso functions.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
lib/vdso/gettimeofday.c | 83 +++++++++++++++++++++++++++++++++--------
1 file changed, 67 insertions(+), 16 deletions(-)
diff --git a/lib/vdso/gettimeofday.c b/lib/vdso/gettimeofday.c
index f8b8ec5e63ac..72d65dd50cb4 100644
--- a/lib/vdso/gettimeofday.c
+++ b/lib/vdso/gettimeofday.c
@@ -206,9 +206,9 @@ static __always_inline int do_coarse(const struct vdso_data *vd, clockid_t clk,
}
static __maybe_unused int
-__cvdso_clock_gettime_common(clockid_t clock, struct __kernel_timespec *ts)
+__cvdso_clock_gettime_common(const struct vdso_data *vd, clockid_t clock,
+ struct __kernel_timespec *ts)
{
- const struct vdso_data *vd = __arch_get_vdso_data();
u32 msk;
/* Check for negative values or invalid clocks */
@@ -233,23 +233,33 @@ __cvdso_clock_gettime_common(clockid_t clock, struct __kernel_timespec *ts)
}
static __maybe_unused int
-__cvdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts)
+__cvdso_clock_gettime_data(const struct vdso_data *vd, clockid_t clock,
+ struct __kernel_timespec *ts)
{
- int ret = __cvdso_clock_gettime_common(clock, ts);
+ int ret = __cvdso_clock_gettime_common(vd, clock, ts);
if (unlikely(ret))
return clock_gettime_fallback(clock, ts);
return 0;
}
+static __maybe_unused int
+__cvdso_clock_gettime(clockid_t clock, struct __kernel_timespec *ts)
+{
+ const struct vdso_data *vd = __arch_get_vdso_data();
+
+ return __cvdso_clock_gettime_data(vd, clock, ts);
+}
+
#ifdef BUILD_VDSO32
static __maybe_unused int
-__cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res)
+__cvdso_clock_gettime32_data(const struct vdso_data *vd, clockid_t clock,
+ struct old_timespec32 *res)
{
struct __kernel_timespec ts;
int ret;
- ret = __cvdso_clock_gettime_common(clock, &ts);
+ ret = __cvdso_clock_gettime_common(vd, clock, &ts);
if (unlikely(ret))
return clock_gettime32_fallback(clock, res);
@@ -260,13 +270,21 @@ __cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res)
return ret;
}
-#endif /* BUILD_VDSO32 */
static __maybe_unused int
-__cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz)
+__cvdso_clock_gettime32(clockid_t clock, struct old_timespec32 *res)
{
const struct vdso_data *vd = __arch_get_vdso_data();
+ return __cvdso_clock_gettime32_data(vd, clock, res);
+}
+#endif /* BUILD_VDSO32 */
+
+static __maybe_unused int
+__cvdso_gettimeofday_data(const struct vdso_data *vd,
+ struct __kernel_old_timeval *tv, struct timezone *tz)
+{
+
if (likely(tv != NULL)) {
struct __kernel_timespec ts;
@@ -289,10 +307,18 @@ __cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz)
return 0;
}
-#ifdef VDSO_HAS_TIME
-static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time)
+static __maybe_unused int
+__cvdso_gettimeofday(struct __kernel_old_timeval *tv, struct timezone *tz)
{
const struct vdso_data *vd = __arch_get_vdso_data();
+
+ return __cvdso_gettimeofday_data(vd, tv, tz);
+}
+
+#ifdef VDSO_HAS_TIME
+static __maybe_unused __kernel_old_time_t
+__cvdso_time_data(const struct vdso_data *vd, __kernel_old_time_t *time)
+{
__kernel_old_time_t t;
if (IS_ENABLED(CONFIG_TIME_NS) && vd->clock_mode == VCLOCK_TIMENS)
@@ -305,13 +331,20 @@ static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time
return t;
}
+
+static __maybe_unused __kernel_old_time_t __cvdso_time(__kernel_old_time_t *time)
+{
+ const struct vdso_data *vd = __arch_get_vdso_data();
+
+ return __cvdso_time_data(vd, time);
+}
#endif /* VDSO_HAS_TIME */
#ifdef VDSO_HAS_CLOCK_GETRES
static __maybe_unused
-int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res)
+int __cvdso_clock_getres_common(const struct vdso_data *vd, clockid_t clock,
+ struct __kernel_timespec *res)
{
- const struct vdso_data *vd = __arch_get_vdso_data();
u32 msk;
u64 ns;
@@ -349,23 +382,33 @@ int __cvdso_clock_getres_common(clockid_t clock, struct __kernel_timespec *res)
}
static __maybe_unused
-int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res)
+int __cvdso_clock_getres_data(const struct vdso_data *vd, clockid_t clock,
+ struct __kernel_timespec *res)
{
- int ret = __cvdso_clock_getres_common(clock, res);
+ int ret = __cvdso_clock_getres_common(vd, clock, res);
if (unlikely(ret))
return clock_getres_fallback(clock, res);
return 0;
}
+static __maybe_unused
+int __cvdso_clock_getres(clockid_t clock, struct __kernel_timespec *res)
+{
+ const struct vdso_data *vd = __arch_get_vdso_data();
+
+ return __cvdso_clock_getres_data(vd, clock, res);
+}
+
#ifdef BUILD_VDSO32
static __maybe_unused int
-__cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res)
+__cvdso_clock_getres_time32_data(const struct vdso_data *vd, clockid_t clock,
+ struct old_timespec32 *res)
{
struct __kernel_timespec ts;
int ret;
- ret = __cvdso_clock_getres_common(clock, &ts);
+ ret = __cvdso_clock_getres_common(vd, clock, &ts);
if (unlikely(ret))
return clock_getres32_fallback(clock, res);
@@ -376,5 +419,13 @@ __cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res)
}
return ret;
}
+
+static __maybe_unused int
+__cvdso_clock_getres_time32(clockid_t clock, struct old_timespec32 *res)
+{
+ const struct vdso_data *vd = __arch_get_vdso_data();
+
+ return __cvdso_clock_getres_time32_data(vd, clock, res);
+}
#endif /* BUILD_VDSO32 */
#endif /* VDSO_HAS_CLOCK_GETRES */
--
2.25.0
next prev parent reply other threads:[~2020-01-30 16:08 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-30 16:08 [PATCH v5 0/6] powerpc: switch VDSO to C implementation Christophe Leroy
2020-01-30 16:08 ` [PATCH v5 1/6] powerpc/vdso64: Switch from __get_datapage() to get_datapage inline macro Christophe Leroy
2020-01-30 16:08 ` [PATCH v5 2/6] powerpc/vdso: Remove __kernel_datapage_offset and simplify __get_datapage() Christophe Leroy
2020-01-30 16:08 ` Christophe Leroy [this message]
2020-01-30 16:08 ` [PATCH v5 4/6] lib/vdso: Allow fixed clock mode Christophe Leroy
2020-01-30 16:08 ` [PATCH v5 5/6] lib/vdso: Allow architectures to override the ns shift operation Christophe Leroy
2020-01-30 16:08 ` [PATCH v5 6/6] powerpc/vdso: Switch VDSO to generic C implementation Christophe Leroy
2020-02-03 11:27 ` kbuild test robot
2020-02-03 11:59 ` Arnd Bergmann
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