From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3t7x8g6dVTzDvPR for ; Wed, 2 Nov 2016 16:13:55 +1100 (AEDT) Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id uA25DUU0107137 for ; Wed, 2 Nov 2016 01:13:54 -0400 Received: from e23smtp02.au.ibm.com (e23smtp02.au.ibm.com [202.81.31.144]) by mx0a-001b2d01.pphosted.com with ESMTP id 26f5q57emm-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 02 Nov 2016 01:13:53 -0400 Received: from localhost by e23smtp02.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 2 Nov 2016 15:13:51 +1000 Received: from d23relay09.au.ibm.com (d23relay09.au.ibm.com [9.185.63.181]) by d23dlp02.au.ibm.com (Postfix) with ESMTP id 76DA22BB0054 for ; Wed, 2 Nov 2016 16:13:48 +1100 (EST) Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay09.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id uA25DmJY4850062 for ; Wed, 2 Nov 2016 16:13:48 +1100 Received: from d23av02.au.ibm.com (localhost [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id uA25DkM3007842 for ; Wed, 2 Nov 2016 16:13:48 +1100 From: Pan Xinhui To: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, virtualization@lists.linux-foundation.org, linux-s390@vger.kernel.org, xen-devel-request@lists.xenproject.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org, x86@kernel.org Cc: benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, mingo@redhat.com, peterz@infradead.org, paulmck@linux.vnet.ibm.com, will.deacon@arm.com, kernellwp@gmail.com, jgross@suse.com, pbonzini@redhat.com, bsingharora@gmail.com, boqun.feng@gmail.com, borntraeger@de.ibm.com, rkrcmar@redhat.com, David.Laight@ACULAB.COM, dave@stgolabs.net, konrad.wilk@oracle.com Subject: [PATCH v7 05/11] s390/spinlock: Provide vcpu_is_preempted Date: Wed, 2 Nov 2016 05:08:32 -0400 In-Reply-To: <1478077718-37424-1-git-send-email-xinhui.pan@linux.vnet.ibm.com> References: <1478077718-37424-1-git-send-email-xinhui.pan@linux.vnet.ibm.com> Message-Id: <1478077718-37424-6-git-send-email-xinhui.pan@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Christian Borntraeger this implements the s390 backend for commit "kernel/sched: introduce vcpu preempted check interface" by reworking the existing smp_vcpu_scheduled into arch_vcpu_is_preempted. We can then also get rid of the local cpu_is_preempted function by moving the CIF_ENABLED_WAIT test into arch_vcpu_is_preempted. Signed-off-by: Christian Borntraeger Acked-by: Heiko Carstens --- arch/s390/include/asm/spinlock.h | 8 ++++++++ arch/s390/kernel/smp.c | 9 +++++++-- arch/s390/lib/spinlock.c | 25 ++++++++----------------- 3 files changed, 23 insertions(+), 19 deletions(-) diff --git a/arch/s390/include/asm/spinlock.h b/arch/s390/include/asm/spinlock.h index 7e9e09f..7ecd890 100644 --- a/arch/s390/include/asm/spinlock.h +++ b/arch/s390/include/asm/spinlock.h @@ -23,6 +23,14 @@ _raw_compare_and_swap(unsigned int *lock, unsigned int old, unsigned int new) return __sync_bool_compare_and_swap(lock, old, new); } +#ifndef CONFIG_SMP +static inline bool arch_vcpu_is_preempted(int cpu) { return false; } +#else +bool arch_vcpu_is_preempted(int cpu); +#endif + +#define vcpu_is_preempted arch_vcpu_is_preempted + /* * Simple spin lock operations. There are two variants, one clears IRQ's * on the local processor, one does not. diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c index 35531fe..b988ed1 100644 --- a/arch/s390/kernel/smp.c +++ b/arch/s390/kernel/smp.c @@ -368,10 +368,15 @@ int smp_find_processor_id(u16 address) return -1; } -int smp_vcpu_scheduled(int cpu) +bool arch_vcpu_is_preempted(int cpu) { - return pcpu_running(pcpu_devices + cpu); + if (test_cpu_flag_of(CIF_ENABLED_WAIT, cpu)) + return false; + if (pcpu_running(pcpu_devices + cpu)) + return false; + return true; } +EXPORT_SYMBOL(arch_vcpu_is_preempted); void smp_yield_cpu(int cpu) { diff --git a/arch/s390/lib/spinlock.c b/arch/s390/lib/spinlock.c index e5f50a7..e48a48e 100644 --- a/arch/s390/lib/spinlock.c +++ b/arch/s390/lib/spinlock.c @@ -37,15 +37,6 @@ static inline void _raw_compare_and_delay(unsigned int *lock, unsigned int old) asm(".insn rsy,0xeb0000000022,%0,0,%1" : : "d" (old), "Q" (*lock)); } -static inline int cpu_is_preempted(int cpu) -{ - if (test_cpu_flag_of(CIF_ENABLED_WAIT, cpu)) - return 0; - if (smp_vcpu_scheduled(cpu)) - return 0; - return 1; -} - void arch_spin_lock_wait(arch_spinlock_t *lp) { unsigned int cpu = SPINLOCK_LOCKVAL; @@ -62,7 +53,7 @@ void arch_spin_lock_wait(arch_spinlock_t *lp) continue; } /* First iteration: check if the lock owner is running. */ - if (first_diag && cpu_is_preempted(~owner)) { + if (first_diag && arch_vcpu_is_preempted(~owner)) { smp_yield_cpu(~owner); first_diag = 0; continue; @@ -81,7 +72,7 @@ void arch_spin_lock_wait(arch_spinlock_t *lp) * yield the CPU unconditionally. For LPAR rely on the * sense running status. */ - if (!MACHINE_IS_LPAR || cpu_is_preempted(~owner)) { + if (!MACHINE_IS_LPAR || arch_vcpu_is_preempted(~owner)) { smp_yield_cpu(~owner); first_diag = 0; } @@ -108,7 +99,7 @@ void arch_spin_lock_wait_flags(arch_spinlock_t *lp, unsigned long flags) continue; } /* Check if the lock owner is running. */ - if (first_diag && cpu_is_preempted(~owner)) { + if (first_diag && arch_vcpu_is_preempted(~owner)) { smp_yield_cpu(~owner); first_diag = 0; continue; @@ -127,7 +118,7 @@ void arch_spin_lock_wait_flags(arch_spinlock_t *lp, unsigned long flags) * yield the CPU unconditionally. For LPAR rely on the * sense running status. */ - if (!MACHINE_IS_LPAR || cpu_is_preempted(~owner)) { + if (!MACHINE_IS_LPAR || arch_vcpu_is_preempted(~owner)) { smp_yield_cpu(~owner); first_diag = 0; } @@ -165,7 +156,7 @@ void _raw_read_lock_wait(arch_rwlock_t *rw) owner = 0; while (1) { if (count-- <= 0) { - if (owner && cpu_is_preempted(~owner)) + if (owner && arch_vcpu_is_preempted(~owner)) smp_yield_cpu(~owner); count = spin_retry; } @@ -211,7 +202,7 @@ void _raw_write_lock_wait(arch_rwlock_t *rw, unsigned int prev) owner = 0; while (1) { if (count-- <= 0) { - if (owner && cpu_is_preempted(~owner)) + if (owner && arch_vcpu_is_preempted(~owner)) smp_yield_cpu(~owner); count = spin_retry; } @@ -241,7 +232,7 @@ void _raw_write_lock_wait(arch_rwlock_t *rw) owner = 0; while (1) { if (count-- <= 0) { - if (owner && cpu_is_preempted(~owner)) + if (owner && arch_vcpu_is_preempted(~owner)) smp_yield_cpu(~owner); count = spin_retry; } @@ -285,7 +276,7 @@ void arch_lock_relax(unsigned int cpu) { if (!cpu) return; - if (MACHINE_IS_LPAR && !cpu_is_preempted(~cpu)) + if (MACHINE_IS_LPAR && !arch_vcpu_is_preempted(~cpu)) return; smp_yield_cpu(~cpu); } -- 2.4.11