When all vCPU threads on one pCPU are put to sleep (e.g., when all
guests execute HLT), hv would schedule to idle thread. Currently the
idle thread executes PAUSE which does not enter any c-state and consumes
a lot of power. This patch is to support HLT in the idle thread.
When we switch to HLT, we have to make sure events that would wake a
vCPU must also be able to wake the pCPU. Those events are either
generated by local interrupt or issued by other pCPUs followed by an
ipi kick.
Each of them have an interrupt involved, so they are also able to wake
the halted pCPU. Except when the pCPU has just scheduled to idle thread
but not yet halted, interrupts could be missed.
sleep-------schedule to idle------IRQ ON---HLT--(kick missed)
^
wake---kick|
This areas should be protected. This is done by a safe halt
mechanism leveraging STI instruction’s delay effect (same as Linux).
vCPUs with lapic_pt or hv with CONFIG_KEEP_IRQ_DISABLED=y does not allow
interrupts in root mode, so they could never wake from HLT (INIT kick
does not wake HLT in root mode either). They should continue using PAUSE
in idle.
Tracked-On: #8507
Signed-off-by: Wu Zhou <wu.zhou@intel.com>
Reviewed-by: Junjie Mao <junjie.mao@intel.com>
Current IO emulation is synchronous. The user VM need to wait for the
completion of the the I/O request before return. But Virtio Spec
introduces introduces asynchronous IO with a new register in MMIO/PIO
space named NOTIFY, to be used for FE driver to notify BE driver, ACRN
hypervisor can emulate this register by sending a notification to vCPU
in Service VM side. This way, FE side can resume to work without waiting
for the full completion of BE side response.
Tracked-On: #8209
Signed-off-by: Conghui <conghui.chen@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
INIT signal has been used to kick off the partitioned pCPU, like RTVM,
whose LAPIC is pass-through. notification IPI is used to kick off
sharing pCPU.
Add mode_to_kick_pcpu in per-cpu to control the way of kicking
pCPU.
Tracked-On: #8207
Signed-off-by: Minggui Cao <minggui.cao@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
Modified the copyright year range in code, and corrected "int32_tel"
into "Intel" in two "hypervisor/include/debug/profiling.h" and
"hypervisor/include/debug/profiling_internal.h".
Tracked-On: #7559
Signed-off-by: Ziheng Li <ziheng.li@intel.com>
Many of the license and Intel copyright headers include the "All rights
reserved" string. It is not relevant in the context of the BSD-3-Clause
license that the code is released under. This patch removes those strings
throughout the code (hypervisor, devicemodel and misc).
Tracked-On: #7254
Signed-off-by: Geoffroy Van Cutsem <geoffroy.vancutsem@intel.com>
This patch adds a new priority based scheduler to support
vCPU scheduling based on their pre-configured priorities.
A vCPU can be running only if there is no higher priority
vCPU running on the same pCPU.
Tracked-On: #6571
Signed-off-by: Jie Deng <jie.deng@intel.com>
x86/timer.[ch] was moved to the common directory largely unchanged.
x86 specific code now resides in x86/tsc_deadline_timer.c and its
interface was defined in hw/hw_timer.h. The interface defines two
functions: init_hw_timer() and set_hw_timeout() that provides HW
specific initialization and timer interrupt source.
Other than these two functions, the timer module is largely arch
agnostic.
Tracked-On: #5920
Signed-off-by: Rong Liu <rong2.liu@intel.com>
Reviewed-by: Jason Chen CJ <jason.cj.chen@intel.com>
Instead of "#include <x86/foo.h>", use "#include <asm/foo.h>".
In other words, we are adopting the same practice in Linux kernel.
Tracked-On: #5920
Signed-off-by: Liang Yi <yi.liang@intel.com>
Reviewed-by: Jason Chen CJ <jason.cj.chen@intel.com>
