mainlining shenanigans
Remove the vCPU from the wakeup list before updating the notification vector in the posted interrupt post-block helper. There is no need to wake the current vCPU as it is by definition not blocking. Practically speaking this is a nop as it only shaves a few meager cycles in the unlikely case that the vCPU was migrated and the previous pCPU gets a wakeup IRQ right before PID.NV is updated. The real motivation is to allow for more readable code in the future, when post-block is merged with vmx_vcpu_pi_load(), at which point removal from the list will be conditional on the old notification vector. Opportunistically add comments to document why KVM has a per-CPU spinlock that, at first glance, appears to be taken only on the owning CPU. Explicitly call out that the spinlock must be taken with IRQs disabled, a detail that was "lost" when KVM switched from spin_lock_irqsave() to spin_lock(), with IRQs disabled for the entirety of the relevant path. Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20211009021236.4122790-29-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.