From: Nicholas Piggin <npiggin@gmail.com>
To: linuxppc-dev@lists.ozlabs.org
Cc: Nicholas Piggin <npiggin@gmail.com>,
Will Deacon <will@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Boqun Feng <boqun.feng@gmail.com>, Ingo Molnar <mingo@redhat.com>,
Waiman Long <longman@redhat.com>,
Anton Blanchard <anton@ozlabs.org>,
linux-kernel@vger.kernel.org,
virtualization@lists.linux-foundation.org,
kvm-ppc@vger.kernel.org, linux-arch@vger.kernel.org
Subject: [PATCH v3 2/6] powerpc/pseries: move some PAPR paravirt functions to their own file
Date: Mon, 6 Jul 2020 14:35:36 +1000 [thread overview]
Message-ID: <20200706043540.1563616-3-npiggin@gmail.com> (raw)
In-Reply-To: <20200706043540.1563616-1-npiggin@gmail.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/include/asm/paravirt.h | 61 +++++++++++++++++++++++++++++
arch/powerpc/include/asm/spinlock.h | 24 +-----------
arch/powerpc/lib/locks.c | 12 +++---
3 files changed, 68 insertions(+), 29 deletions(-)
create mode 100644 arch/powerpc/include/asm/paravirt.h
diff --git a/arch/powerpc/include/asm/paravirt.h b/arch/powerpc/include/asm/paravirt.h
new file mode 100644
index 000000000000..7a8546660a63
--- /dev/null
+++ b/arch/powerpc/include/asm/paravirt.h
@@ -0,0 +1,61 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef __ASM_PARAVIRT_H
+#define __ASM_PARAVIRT_H
+#ifdef __KERNEL__
+
+#include <linux/jump_label.h>
+#include <asm/smp.h>
+#ifdef CONFIG_PPC64
+#include <asm/paca.h>
+#include <asm/hvcall.h>
+#endif
+
+#ifdef CONFIG_PPC_SPLPAR
+DECLARE_STATIC_KEY_FALSE(shared_processor);
+
+static inline bool is_shared_processor(void)
+{
+ return static_branch_unlikely(&shared_processor);
+}
+
+/* If bit 0 is set, the cpu has been preempted */
+static inline u32 yield_count_of(int cpu)
+{
+ __be32 yield_count = READ_ONCE(lppaca_of(cpu).yield_count);
+ return be32_to_cpu(yield_count);
+}
+
+static inline void yield_to_preempted(int cpu, u32 yield_count)
+{
+ plpar_hcall_norets(H_CONFER, get_hard_smp_processor_id(cpu), yield_count);
+}
+#else
+static inline bool is_shared_processor(void)
+{
+ return false;
+}
+
+static inline u32 yield_count_of(int cpu)
+{
+ return 0;
+}
+
+extern void ___bad_yield_to_preempted(void);
+static inline void yield_to_preempted(int cpu, u32 yield_count)
+{
+ ___bad_yield_to_preempted(); /* This would be a bug */
+}
+#endif
+
+#define vcpu_is_preempted vcpu_is_preempted
+static inline bool vcpu_is_preempted(int cpu)
+{
+ if (!is_shared_processor())
+ return false;
+ if (yield_count_of(cpu) & 1)
+ return true;
+ return false;
+}
+
+#endif /* __KERNEL__ */
+#endif /* __ASM_PARAVIRT_H */
diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h
index 2d620896cdae..79be9bb10bbb 100644
--- a/arch/powerpc/include/asm/spinlock.h
+++ b/arch/powerpc/include/asm/spinlock.h
@@ -15,11 +15,10 @@
*
* (the type definitions are in asm/spinlock_types.h)
*/
-#include <linux/jump_label.h>
#include <linux/irqflags.h>
+#include <asm/paravirt.h>
#ifdef CONFIG_PPC64
#include <asm/paca.h>
-#include <asm/hvcall.h>
#endif
#include <asm/synch.h>
#include <asm/ppc-opcode.h>
@@ -35,18 +34,6 @@
#define LOCK_TOKEN 1
#endif
-#ifdef CONFIG_PPC_PSERIES
-DECLARE_STATIC_KEY_FALSE(shared_processor);
-
-#define vcpu_is_preempted vcpu_is_preempted
-static inline bool vcpu_is_preempted(int cpu)
-{
- if (!static_branch_unlikely(&shared_processor))
- return false;
- return !!(be32_to_cpu(lppaca_of(cpu).yield_count) & 1);
-}
-#endif
-
static __always_inline int arch_spin_value_unlocked(arch_spinlock_t lock)
{
return lock.slock == 0;
@@ -110,15 +97,6 @@ static inline void splpar_spin_yield(arch_spinlock_t *lock) {};
static inline void splpar_rw_yield(arch_rwlock_t *lock) {};
#endif
-static inline bool is_shared_processor(void)
-{
-#ifdef CONFIG_PPC_SPLPAR
- return static_branch_unlikely(&shared_processor);
-#else
- return false;
-#endif
-}
-
static inline void spin_yield(arch_spinlock_t *lock)
{
if (is_shared_processor())
diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c
index 6440d5943c00..04165b7a163f 100644
--- a/arch/powerpc/lib/locks.c
+++ b/arch/powerpc/lib/locks.c
@@ -27,14 +27,14 @@ void splpar_spin_yield(arch_spinlock_t *lock)
return;
holder_cpu = lock_value & 0xffff;
BUG_ON(holder_cpu >= NR_CPUS);
- yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count);
+
+ yield_count = yield_count_of(holder_cpu);
if ((yield_count & 1) == 0)
return; /* virtual cpu is currently running */
rmb();
if (lock->slock != lock_value)
return; /* something has changed */
- plpar_hcall_norets(H_CONFER,
- get_hard_smp_processor_id(holder_cpu), yield_count);
+ yield_to_preempted(holder_cpu, yield_count);
}
EXPORT_SYMBOL_GPL(splpar_spin_yield);
@@ -53,13 +53,13 @@ void splpar_rw_yield(arch_rwlock_t *rw)
return; /* no write lock at present */
holder_cpu = lock_value & 0xffff;
BUG_ON(holder_cpu >= NR_CPUS);
- yield_count = be32_to_cpu(lppaca_of(holder_cpu).yield_count);
+
+ yield_count = yield_count_of(holder_cpu);
if ((yield_count & 1) == 0)
return; /* virtual cpu is currently running */
rmb();
if (rw->lock != lock_value)
return; /* something has changed */
- plpar_hcall_norets(H_CONFER,
- get_hard_smp_processor_id(holder_cpu), yield_count);
+ yield_to_preempted(holder_cpu, yield_count);
}
#endif
--
2.23.0
next prev parent reply other threads:[~2020-07-06 4:35 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-06 4:35 [PATCH v3 0/6] powerpc: queued spinlocks and rwlocks Nicholas Piggin
2020-07-06 4:35 ` [PATCH v3 1/6] powerpc/powernv: must include hvcall.h to get PAPR defines Nicholas Piggin
2020-07-09 10:05 ` Michael Ellerman
2020-07-06 4:35 ` Nicholas Piggin [this message]
2020-07-09 10:11 ` [PATCH v3 2/6] powerpc/pseries: move some PAPR paravirt functions to their own file Michael Ellerman
2020-07-06 4:35 ` [PATCH v3 3/6] powerpc: move spinlock implementation to simple_spinlock Nicholas Piggin
2020-07-09 10:15 ` Michael Ellerman
2020-07-06 4:35 ` [PATCH v3 4/6] powerpc/64s: implement queued spinlocks and rwlocks Nicholas Piggin
2020-07-09 10:20 ` Michael Ellerman
2020-07-09 10:33 ` Peter Zijlstra
2020-07-23 14:37 ` Michal Suchánek
2020-07-06 4:35 ` [PATCH v3 5/6] powerpc/pseries: implement paravirt qspinlocks for SPLPAR Nicholas Piggin
2020-07-09 10:53 ` Michael Ellerman
2020-07-09 11:03 ` Peter Zijlstra
2020-07-09 16:06 ` Waiman Long
2020-07-23 14:00 ` Peter Zijlstra
2020-07-23 18:32 ` Waiman Long
2020-07-23 18:47 ` peterz
2020-07-23 19:04 ` Waiman Long
2020-07-23 19:58 ` peterz
2020-07-23 20:30 ` Segher Boessenkool
2020-07-23 21:58 ` Waiman Long
2020-07-23 14:09 ` Nicholas Piggin
2020-07-06 4:35 ` [PATCH v3 6/6] powerpc/qspinlock: optimised atomic_try_cmpxchg_lock that adds the lock hint Nicholas Piggin
2020-07-06 18:39 ` [PATCH v3 0/6] powerpc: queued spinlocks and rwlocks Waiman Long
2020-07-07 5:57 ` Nicholas Piggin
2020-07-08 3:33 ` Waiman Long
2020-07-08 5:10 ` Nicholas Piggin
2020-07-08 23:50 ` Waiman Long
2020-07-08 23:58 ` Waiman Long
2020-07-08 8:32 ` Peter Zijlstra
2020-07-08 23:53 ` Waiman Long
2020-07-08 8:41 ` Peter Zijlstra
2020-07-08 23:54 ` Waiman Long
2020-07-09 8:31 ` Peter Zijlstra
2020-07-21 11:20 ` Nicholas Piggin
2020-07-21 11:08 ` Nicholas Piggin
2020-07-21 14:36 ` Waiman Long
2020-07-23 13:30 ` Nicholas Piggin
2020-07-23 14:29 ` Waiman Long
2020-07-23 16:12 ` Nicholas Piggin
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