From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Junaid Shahid <junaids@google.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Thomas Gleixner <tglx@linutronix.de>,
Ben Hutchings <ben@decadent.org.uk>
Subject: [PATCH 4.9 29/31] kvm: Add helper function for creating VM worker threads
Date: Fri, 15 Nov 2019 14:20:58 +0800 [thread overview]
Message-ID: <20191115062020.017377287@linuxfoundation.org> (raw)
In-Reply-To: <20191115062009.813108457@linuxfoundation.org>
From: Junaid Shahid <junaids@google.com>
commit c57c80467f90e5504c8df9ad3555d2c78800bf94 upstream.
Add a function to create a kernel thread associated with a given VM. In
particular, it ensures that the worker thread inherits the priority and
cgroups of the calling thread.
Signed-off-by: Junaid Shahid <junaids@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/linux/kvm_host.h | 6 +++
virt/kvm/kvm_main.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 90 insertions(+)
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1208,4 +1208,10 @@ static inline bool vcpu_valid_wakeup(str
}
#endif /* CONFIG_HAVE_KVM_INVALID_WAKEUPS */
+typedef int (*kvm_vm_thread_fn_t)(struct kvm *kvm, uintptr_t data);
+
+int kvm_vm_create_worker_thread(struct kvm *kvm, kvm_vm_thread_fn_t thread_fn,
+ uintptr_t data, const char *name,
+ struct task_struct **thread_ptr);
+
#endif
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -49,6 +49,7 @@
#include <linux/slab.h>
#include <linux/sort.h>
#include <linux/bsearch.h>
+#include <linux/kthread.h>
#include <asm/processor.h>
#include <asm/io.h>
@@ -3987,3 +3988,86 @@ void kvm_exit(void)
kvm_vfio_ops_exit();
}
EXPORT_SYMBOL_GPL(kvm_exit);
+
+struct kvm_vm_worker_thread_context {
+ struct kvm *kvm;
+ struct task_struct *parent;
+ struct completion init_done;
+ kvm_vm_thread_fn_t thread_fn;
+ uintptr_t data;
+ int err;
+};
+
+static int kvm_vm_worker_thread(void *context)
+{
+ /*
+ * The init_context is allocated on the stack of the parent thread, so
+ * we have to locally copy anything that is needed beyond initialization
+ */
+ struct kvm_vm_worker_thread_context *init_context = context;
+ struct kvm *kvm = init_context->kvm;
+ kvm_vm_thread_fn_t thread_fn = init_context->thread_fn;
+ uintptr_t data = init_context->data;
+ int err;
+
+ err = kthread_park(current);
+ /* kthread_park(current) is never supposed to return an error */
+ WARN_ON(err != 0);
+ if (err)
+ goto init_complete;
+
+ err = cgroup_attach_task_all(init_context->parent, current);
+ if (err) {
+ kvm_err("%s: cgroup_attach_task_all failed with err %d\n",
+ __func__, err);
+ goto init_complete;
+ }
+
+ set_user_nice(current, task_nice(init_context->parent));
+
+init_complete:
+ init_context->err = err;
+ complete(&init_context->init_done);
+ init_context = NULL;
+
+ if (err)
+ return err;
+
+ /* Wait to be woken up by the spawner before proceeding. */
+ kthread_parkme();
+
+ if (!kthread_should_stop())
+ err = thread_fn(kvm, data);
+
+ return err;
+}
+
+int kvm_vm_create_worker_thread(struct kvm *kvm, kvm_vm_thread_fn_t thread_fn,
+ uintptr_t data, const char *name,
+ struct task_struct **thread_ptr)
+{
+ struct kvm_vm_worker_thread_context init_context = {};
+ struct task_struct *thread;
+
+ *thread_ptr = NULL;
+ init_context.kvm = kvm;
+ init_context.parent = current;
+ init_context.thread_fn = thread_fn;
+ init_context.data = data;
+ init_completion(&init_context.init_done);
+
+ thread = kthread_run(kvm_vm_worker_thread, &init_context,
+ "%s-%d", name, task_pid_nr(current));
+ if (IS_ERR(thread))
+ return PTR_ERR(thread);
+
+ /* kthread_run is never supposed to return NULL */
+ WARN_ON(thread == NULL);
+
+ wait_for_completion(&init_context.init_done);
+
+ if (!init_context.err)
+ *thread_ptr = thread;
+
+ return init_context.err;
+}
next prev parent reply other threads:[~2019-11-15 6:23 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-15 6:20 [PATCH 4.9 00/31] 4.9.202-stable review Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 01/31] kvm: mmu: Dont read PDPTEs when paging is not enabled Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 02/31] Bluetooth: hci_ldisc: Postpone HCI_UART_PROTO_READY bit set in hci_uart_set_proto() Greg Kroah-Hartman
2019-11-15 16:10 ` Ralph Siemsen
2019-11-16 7:56 ` Greg Kroah-Hartman
2019-11-18 20:27 ` Ralph Siemsen
2019-11-19 4:47 ` Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 03/31] MIPS: BCM63XX: fix switch core reset on BCM6368 Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 04/31] usb: gadget: core: unmap request from DMA only if previously mapped Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 05/31] KVM: x86: use Intel speculation bugs and features as derived in generic x86 code Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 06/31] x86/msr: Add the IA32_TSX_CTRL MSR Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 07/31] x86/cpu: Add a helper function x86_read_arch_cap_msr() Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 08/31] x86/cpu: Add a "tsx=" cmdline option with TSX disabled by default Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 09/31] x86/speculation/taa: Add mitigation for TSX Async Abort Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 10/31] x86/speculation/taa: Add sysfs reporting " Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 11/31] kvm/x86: Export MDS_NO=0 to guests when TSX is enabled Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 12/31] x86/tsx: Add "auto" option to the tsx= cmdline parameter Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 13/31] x86/speculation/taa: Add documentation for TSX Async Abort Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 14/31] x86/tsx: Add config options to set tsx=on|off|auto Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 15/31] x86/speculation/taa: Fix printing of TAA_MSG_SMT on IBRS_ALL CPUs Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 16/31] KVM: x86: simplify ept_misconfig Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 17/31] KVM: x86: extend usage of RET_MMIO_PF_* constants Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 18/31] kvm: Convert kvm_lock to a mutex Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 19/31] kvm: x86: Do not release the page inside mmu_set_spte() Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 20/31] KVM: x86: make FNAME(fetch) and __direct_map more similar Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 21/31] KVM: x86: remove now unneeded hugepage gfn adjustment Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 22/31] KVM: x86: change kvm_mmu_page_get_gfn BUG_ON to WARN_ON Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 23/31] KVM: x86: Add is_executable_pte() Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 24/31] KVM: x86: add tracepoints around __direct_map and FNAME(fetch) Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 25/31] KVM: vmx, svm: always run with EFER.NXE=1 when shadow paging is active Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 26/31] x86/bugs: Add ITLB_MULTIHIT bug infrastructure Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 27/31] cpu/speculation: Uninline and export CPU mitigations helpers Greg Kroah-Hartman
2019-11-15 6:20 ` [PATCH 4.9 28/31] kvm: mmu: ITLB_MULTIHIT mitigation Greg Kroah-Hartman
2019-11-15 6:20 ` Greg Kroah-Hartman [this message]
2019-11-15 6:20 ` [PATCH 4.9 30/31] kvm: x86: mmu: Recovery of shattered NX large pages Greg Kroah-Hartman
2019-11-15 6:21 ` [PATCH 4.9 31/31] Documentation: Add ITLB_MULTIHIT documentation Greg Kroah-Hartman
2019-11-15 12:00 ` [PATCH 4.9 00/31] 4.9.202-stable review kernelci.org bot
2019-11-15 13:50 ` Jon Hunter
2019-11-15 15:07 ` Greg Kroah-Hartman
2019-11-15 13:56 ` Guenter Roeck
2019-11-15 15:08 ` Greg Kroah-Hartman
2019-11-15 15:52 ` Naresh Kamboju
2019-11-16 8:02 ` Greg Kroah-Hartman
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