The Big QEMU Lock (BQL) has many names and they are confusing. The
actual QemuMutex variable is called qemu_global_mutex but it's commonly
referred to as the BQL in discussions and some code comments. The
locking APIs, however, are called qemu_mutex_lock_iothread() and
qemu_mutex_unlock_iothread().
The "iothread" name is historic and comes from when the main thread was
split into into KVM vcpu threads and the "iothread" (now called the main
loop thread). I have contributed to the confusion myself by introducing
a separate --object iothread, a separate concept unrelated to the BQL.
The "iothread" name is no longer appropriate for the BQL. Rename the
locking APIs to:
- void bql_lock(void)
- void bql_unlock(void)
- bool bql_locked(void)
There are more APIs with "iothread" in their names. Subsequent patches
will rename them. There are also comments and documentation that will be
updated in later patches.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Fabiano Rosas <farosas@suse.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Peter Xu <peterx@redhat.com>
Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Acked-by: Hyman Huang <yong.huang@smartx.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20240102153529.486531-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Intel CPUs starting with Haswell-E implement a new MSR called
MSR_CORE_THREAD_COUNT which exposes the number of threads and cores
inside of a package.
This MSR is used by XNU to populate internal data structures and not
implementing it prevents virtual machines with more than 1 vCPU from
booting if the emulated CPU generation is at least Haswell-E.
This patch propagates the existing hvf logic from patch 027ac0cb51
("target/i386/hvf: add rdmsr 35H MSR_CORE_THREAD_COUNT") to TCG.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Message-Id: <20221004225643.65036-2-agraf@csgraf.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Writes to cr8 affect v_tpr. This could set or unset an interrupt
request as the priority might have changed.
Signed-off-by: Lara Lazier <laramglazier@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Moved int_ctl into the CPUX86State structure. It removes some
unnecessary stores and loads, and prepares for tracking the vIRQ
state even when it is masked due to vGIF.
Signed-off-by: Lara Lazier <laramglazier@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stefan Hajnoczi
Alexander Graf
Marc-André Lureau
Philippe Mathieu-Daudé
Lara Lazier
Richard Henderson
Claudio Fontana