Handling page faults using userfaultfd for all the time after vmm-swap
is enabled originally has overhead. By disabling swapping, we can use
crosvm without the overhead when the crosvm become used heavily again.
This also refactor PageHandler and extract register logic to lib.rs.
BUG=b:215093219
TEST=cargo test -p swap
Change-Id: Id81d84ebe40067b4f19b212f6b81cbaf249c0c3c
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/4005474
Reviewed-by: David Stevens <stevensd@chromium.org>
Commit-Queue: Shin Kawamura <kawasin@google.com>
The new command "crosvm swap log_pagefault <socket>" starts logging
page fault events. The log file "page_fault.log" will be located under
the swap directory.
Pagefault event log help up debugging the vmm-swap feature and
understand the memory usage of the guest os.
design document: go/tanooki-phase1-dd
BUG=b:253555760
TEST=manually tested. this is debug feature.
Change-Id: I13e36cef873cd83179032fe8a289c8df71384644
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3954806
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Reviewed-by: David Stevens <stevensd@chromium.org>
Commit-Queue: Shin Kawamura <kawasin@google.com>
Added new crosvm commands "crosvm swap enable" and "crosvm swap status".
swap crate exposes SwapController to control the vmm-swap feature.
When vmm-swap is enabled, all the pages on the GuestMemory are swapped
out to a file and are freed to give a lot of memory back to OS.
design document: go/tanooki-phase1-dd
BUG=b:215093219
TEST=manually tested
Change-Id: Ideb10b0119edd9f47b66c8ac61add21ac08181d4
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3871758
Reviewed-by: David Stevens <stevensd@chromium.org>
Commit-Queue: Shin Kawamura <kawasin@google.com>
userfaultfd returns ENOMEM on register if the corresponding process is
obsolete (e.g. the process dies, memory space is refleshed by execve).
BUG=b:253555760
TEST=cargo test -p swap
Change-Id: I9a6a7f0ed45cdc91bdf17e5d29e4c215b7f575a5
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/4025736
Reviewed-by: David Stevens <stevensd@chromium.org>
Commit-Queue: Shin Kawamura <kawasin@google.com>
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Directories from TempDir::into_path() are not automatically deleted.
We should use TempDir::path() instead.
BUG=b:253555760
TEST=cargo test -p swap
Change-Id: I9f0c5398a7eaa16317f9e40f16231f9b7df0a3a5
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/4033426
Reviewed-by: David Stevens <stevensd@chromium.org>
Commit-Queue: Shin Kawamura <kawasin@google.com>
origin:
https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3932497
ProcessesGuard stops all the crosvm processes except the caller process
using SIGSTOP signal because we must guarantee that no one changes the
guest memory contents while vmm-swap out.
This is a short term solution and will be replaced with device
suspension feature later.
See the "Write back atomicity" section in go/tanooki-phase1-dd
BUG=b:215093219
TEST=cargo build --features=swap
Change-Id: I34e528bf318e5ff9277048f3daf8608e7b09ddc7
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/4016145
Reviewed-by: David Stevens <stevensd@chromium.org>
Commit-Queue: Shin Kawamura <kawasin@google.com>
origin:
https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3944711
PageHandler handles events from userfaultfd using SwapFile.
tests are placed as integration tests since they rely on userfaultfd(2).
design document: go/tanooki-phase1-dd
BUG=b:215093219
TEST=cargo test -p swap page_handler
Change-Id: I64d213d27174d75ee618c4675ea52dbac58bfe59
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/4016144
Reviewed-by: David Stevens <stevensd@chromium.org>
Commit-Queue: Shin Kawamura <kawasin@google.com>
ProcessesGuard stops all the crosvm processes except the caller process
using SIGSTOP signal because we must guarantee that no one changes the
guest memory contents while vmm-swap out.
This is a short term solution and will be replaced with device
suspension feature later.
See the "Write back atomicity" section in go/tanooki-phase1-dd
BUG=b:215093219
TEST=cargo build --features=swap
Change-Id: Ie62a0cf537a045128c0d298e7a73d222fea96ef0
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3932497
Reviewed-by: David Stevens <stevensd@chromium.org>
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
SwapFile saves the active pages in the memory region to a file.
design document: go/tanooki-phase1-dd
BUG=b:215093219
TEST=cargo test -p swap
Change-Id: I4ce16eef36ace832d26622e44444f7549299c1e7
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3930082
Reviewed-by: David Stevens <stevensd@chromium.org>
userfaultfd enables applications to handle page faults on designated
memory area.
vmm-swap feature uses userfaultfd to catch page fault event and swap
in the guest memory from the swap file.
design document: go/tanooki-phase1-dd
BUG=b:215093219
TEST=cargo build --features=swap
Change-Id: I13ae09cd97e4215b00e5d834d4f97eb6b507b892
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3895235
Reviewed-by: David Stevens <stevensd@chromium.org>
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
