From: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
To: tglx@linutronix.de, peterz@infradead.org, tj@kernel.org,
oleg@redhat.com, paulmck@linux.vnet.ibm.com,
rusty@rustcorp.com.au, mingo@kernel.org,
akpm@linux-foundation.org, namhyung@kernel.org,
walken@google.com, vincent.guittot@linaro.org,
laijs@cn.fujitsu.com
Cc: rostedt@goodmis.org, wangyun@linux.vnet.ibm.com,
xiaoguangrong@linux.vnet.ibm.com, sbw@mit.edu,
fweisbec@gmail.com, zhong@linux.vnet.ibm.com,
nikunj@linux.vnet.ibm.com, srivatsa.bhat@linux.vnet.ibm.com,
linux-pm@vger.kernel.org, linux-arch@vger.kernel.org,
linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org, Gleb Natapov <gleb@redhat.com>,
Paolo Bonzini <pbonzini@redhat.com>,
kvm@vger.kernel.org
Subject: [PATCH 28/45] KVM: Use get/put_online_cpus_atomic() to prevent CPU offline
Date: Sun, 23 Jun 2013 19:14:11 +0530 [thread overview]
Message-ID: <20130623134407.19094.28802.stgit@srivatsabhat.in.ibm.com> (raw)
In-Reply-To: <20130623133642.19094.16038.stgit@srivatsabhat.in.ibm.com>
Once stop_machine() is gone from the CPU offline path, we won't be able
to depend on disabling preemption to prevent CPUs from going offline
from under us.
Use the get/put_online_cpus_atomic() APIs to prevent CPUs from going
offline, while invoking from atomic context.
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
---
virt/kvm/kvm_main.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 302681c..5bbfa30 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -174,7 +174,7 @@ static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
zalloc_cpumask_var(&cpus, GFP_ATOMIC);
- me = get_cpu();
+ me = get_online_cpus_atomic();
kvm_for_each_vcpu(i, vcpu, kvm) {
kvm_make_request(req, vcpu);
cpu = vcpu->cpu;
@@ -192,7 +192,7 @@ static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
smp_call_function_many(cpus, ack_flush, NULL, 1);
else
called = false;
- put_cpu();
+ put_online_cpus_atomic();
free_cpumask_var(cpus);
return called;
}
@@ -1707,11 +1707,11 @@ void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
++vcpu->stat.halt_wakeup;
}
- me = get_cpu();
+ me = get_online_cpus_atomic();
if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
if (kvm_arch_vcpu_should_kick(vcpu))
smp_send_reschedule(cpu);
- put_cpu();
+ put_online_cpus_atomic();
}
EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
#endif /* !CONFIG_S390 */
next prev parent reply other threads:[~2013-06-23 13:47 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-06-23 13:37 [PATCH 00/45] CPU hotplug: stop_machine()-free CPU hotplug, part 1 Srivatsa S. Bhat
2013-06-23 13:38 ` [PATCH 01/45] CPU hotplug: Provide APIs to prevent CPU offline from atomic context Srivatsa S. Bhat
2013-06-24 22:49 ` Steven Rostedt
2013-06-23 13:38 ` [PATCH 02/45] CPU hotplug: Clarify the usage of different synchronization APIs Srivatsa S. Bhat
2013-06-23 13:38 ` [PATCH 03/45] Documentation, CPU hotplug: Recommend usage of get/put_online_cpus_atomic() Srivatsa S. Bhat
2013-06-23 13:38 ` [PATCH 04/45] CPU hotplug: Add infrastructure to check lacking hotplug synchronization Srivatsa S. Bhat
2013-06-24 23:26 ` Steven Rostedt
2013-06-25 18:49 ` Srivatsa S. Bhat
2013-06-23 13:39 ` [PATCH 05/45] CPU hotplug: Protect set_cpu_online() to avoid false-positives Srivatsa S. Bhat
2013-06-23 13:39 ` [PATCH 06/45] CPU hotplug: Sprinkle debugging checks to catch locking bugs Srivatsa S. Bhat
2013-06-23 13:39 ` [PATCH 07/45] CPU hotplug: Expose the new debug config option Srivatsa S. Bhat
2013-06-23 15:08 ` Sergei Shtylyov
2013-06-23 18:58 ` Srivatsa S. Bhat
2013-06-23 13:39 ` [PATCH 08/45] CPU hotplug: Convert preprocessor macros to static inline functions Srivatsa S. Bhat
2013-06-23 13:40 ` [PATCH 09/45] smp: Use get/put_online_cpus_atomic() to prevent CPU offline Srivatsa S. Bhat
2013-06-23 13:40 ` [PATCH 10/45] sched/core: " Srivatsa S. Bhat
2013-06-23 13:40 ` [PATCH 11/45] migration: Use raw_spin_lock/unlock since interrupts are already disabled Srivatsa S. Bhat
2013-06-23 13:40 ` [PATCH 12/45] sched/fair: Use get/put_online_cpus_atomic() to prevent CPU offline Srivatsa S. Bhat
2013-06-23 13:40 ` [PATCH 13/45] timer: " Srivatsa S. Bhat
2013-06-23 13:41 ` [PATCH 14/45] sched/rt: " Srivatsa S. Bhat
2013-06-23 13:41 ` [PATCH 15/45] rcu: " Srivatsa S. Bhat
2013-06-23 13:41 ` [PATCH 16/45] tick-broadcast: " Srivatsa S. Bhat
2013-06-23 13:41 ` [PATCH 17/45] time/clocksource: " Srivatsa S. Bhat
2013-06-23 13:42 ` [PATCH 18/45] softirq: " Srivatsa S. Bhat
2013-06-23 13:42 ` [PATCH 19/45] irq: " Srivatsa S. Bhat
2013-06-23 13:42 ` [PATCH 20/45] net: " Srivatsa S. Bhat
2013-06-23 13:42 ` [PATCH 21/45] block: " Srivatsa S. Bhat
2013-06-23 13:42 ` [PATCH 22/45] percpu_counter: " Srivatsa S. Bhat
2013-06-24 17:55 ` Tejun Heo
2013-06-24 18:06 ` Tejun Heo
2013-06-24 18:09 ` Srivatsa S. Bhat
2013-06-23 13:43 ` [PATCH 23/45] infiniband: ehca: " Srivatsa S. Bhat
2013-06-23 13:43 ` [PATCH 24/45] [SCSI] fcoe: " Srivatsa S. Bhat
2013-06-23 13:43 ` [PATCH 25/45] staging/octeon: " Srivatsa S. Bhat
2013-06-23 18:17 ` Greg Kroah-Hartman
2013-06-23 18:55 ` Srivatsa S. Bhat
2013-06-23 19:17 ` Joe Perches
2013-06-24 17:25 ` Srivatsa S. Bhat
2013-06-24 18:17 ` David Daney
2013-06-23 13:43 ` [PATCH 26/45] x86: " Srivatsa S. Bhat
2013-06-23 13:43 ` [PATCH 27/45] perf/x86: " Srivatsa S. Bhat
2013-06-23 13:44 ` Srivatsa S. Bhat [this message]
2013-06-23 13:44 ` [PATCH 29/45] kvm/vmx: " Srivatsa S. Bhat
2013-06-23 13:44 ` [PATCH 30/45] x86/xen: " Srivatsa S. Bhat
2013-06-23 13:45 ` [PATCH 31/45] alpha/smp: " Srivatsa S. Bhat
2013-06-23 17:50 ` Matt Turner
2013-06-23 18:56 ` Srivatsa S. Bhat
2013-06-23 13:45 ` [PATCH 32/45] blackfin/smp: " Srivatsa S. Bhat
2013-06-23 13:45 ` [PATCH 33/45] cris/smp: " Srivatsa S. Bhat
2013-06-24 6:41 ` Jesper Nilsson
2013-06-23 13:45 ` [PATCH 34/45] hexagon/smp: " Srivatsa S. Bhat
2013-06-23 13:45 ` [PATCH 35/45] ia64: irq, perfmon: " Srivatsa S. Bhat
2013-06-23 13:46 ` [PATCH 36/45] ia64: smp, tlb: " Srivatsa S. Bhat
2013-06-23 13:46 ` [PATCH 37/45] m32r: " Srivatsa S. Bhat
2013-06-23 13:46 ` [PATCH 38/45] MIPS: " Srivatsa S. Bhat
2013-06-23 13:46 ` [PATCH 39/45] mn10300: " Srivatsa S. Bhat
2013-06-23 13:47 ` [PATCH 40/45] powerpc, irq: Use GFP_ATOMIC allocations in atomic context Srivatsa S. Bhat
2013-06-25 2:08 ` Michael Ellerman
2013-06-25 2:13 ` Benjamin Herrenschmidt
2013-06-25 2:58 ` Michael Ellerman
2013-06-25 3:13 ` Benjamin Herrenschmidt
2013-06-25 19:20 ` Srivatsa S. Bhat
2013-06-23 13:47 ` [PATCH 41/45] powerpc: Use get/put_online_cpus_atomic() to prevent CPU offline Srivatsa S. Bhat
2013-06-23 13:47 ` [PATCH 42/45] powerpc: Use get/put_online_cpus_atomic() to avoid false-positive warning Srivatsa S. Bhat
2013-06-23 13:47 ` [PATCH 43/45] sh: Use get/put_online_cpus_atomic() to prevent CPU offline Srivatsa S. Bhat
2013-06-23 13:48 ` [PATCH 44/45] sparc: " Srivatsa S. Bhat
2013-06-23 13:48 ` [PATCH 45/45] tile: " Srivatsa S. Bhat
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