For files with O_APPEND, a file write operation gets a file size and uses it as
offset to call an inode write operation. This means that all other operations
which can change a file size should be blocked while the write operation doesn't
complete.
PiperOrigin-RevId: 254873771
The tracee is stopped early during process exit, when registers are still
available, allowing the tracer to see where the exit occurred, whereas the
normal exit notifi? cation is done after the process is finished exiting.
Without this option, dumpAndPanic fails to get registers.
PiperOrigin-RevId: 254852917
The previous number was for the arm architecture.
Also change the statx tests to force them to run on gVisor, which would have
caught this issue.
PiperOrigin-RevId: 254846831
We don't have the plumbing for btime yet, so that field is left off. The
returned mask indicates that btime is absent.
Fixes#343
PiperOrigin-RevId: 254575752
Today we have the logic split in two places between endpoint Read() and the
worker goroutine which actually sends a zero window. This change makes it so
that when a zero window ACK is sent we set a flag in the endpoint which can be
read by the endpoint to decide if it should notify the worker to send a
nonZeroWindow update.
The worker now does not do the check again but instead sends an ACK and flips
the flag right away.
Similarly today when SO_RECVBUF is set the SetSockOpt call has logic
to decide if a zero window update is required. Rather than do that we move
the logic to the worker goroutine and it can check the zeroWindow flag
and send an update if required.
PiperOrigin-RevId: 254505447
Currently, the path tracking in the gofer involves an O(n) lookup of
child fidRefs. This causes a significant overhead on unlinks in
directories with lots of child fidRefs (<4k).
In this transition, pathNode moves from sync.Map to normal synchronized
maps. There is a small chance of contention in walk, but the lock is
held for a very short time (and sync.Map also had a chance of requiring
locking).
OTOH, sync.Map makes it very difficult to add a fidRef reverse map.
PiperOrigin-RevId: 254489952
This test will occasionally fail waiting to read a packet. From repeated runs,
I've seen it up to 1.5s for waitForPackets to complete.
PiperOrigin-RevId: 254484627
Flipcall is a (conceptually) simple local-only RPC mechanism. Compared
to unet, Flipcall does not support passing FDs (support for which will
be provided out of band by another package), requires users to establish
connections manually, and requires user management of concurrency since
each connected Endpoint pair supports only a single RPC at a time;
however, it improves performance by using shared memory for data
(reducing memory copies) and using futexes for control signaling (which
is much cheaper than sendto/recvfrom/sendmsg/recvmsg).
PiperOrigin-RevId: 254471986
Neither fidRefs or children are (directly) synchronized by mu. Remove
the preconditions that say so.
That said, the surrounding does enforce some synchronization guarantees
(e.g., fidRef.renameChildTo does not atomically replace the child in the
maps). I've tried to note the need for callers to do this
synchronization.
I've also renamed the maps to what are (IMO) clearer names. As is, it is
not obvious that pathNode.fidRefs is a map of *child* fidRefs rather
than self fidRefs.
PiperOrigin-RevId: 254446965
Bump up the threshold on number of SIGALRMs received by worker
threads from 50 to 200. Even with the new threshold we still
expect that the majority of SIGALRMs are received by the
thread group leader.
PiperOrigin-RevId: 254289787
Otherwise every call to, say, fs.ContextCanAccessFile() in a benchmark
using contexttest allocates new auth.Credentials, a new
auth.UserNamespace, ...
PiperOrigin-RevId: 254261051
The sendfile syscall's backing doSplice contained a race with regard to
blocking. If the first attempt failed with syserror.ErrWouldBlock and then
the blocking file became ready before registering a waiter, we would just
return the ErrWouldBlock (even if we were supposed to block).
PiperOrigin-RevId: 254114432
Inode ids are only stable across Save/Restore if we have an open FD on the
inode. All tests that compare inode ids must therefor hold an FD open.
PiperOrigin-RevId: 254086603
This allows tasks to have distinct mount namespace, instead of all sharing the
kernel's root mount namespace.
Currently, the only way for a task to get a different mount namespace than the
kernel's root is by explicitly setting a different MountNamespace in
CreateProcessArgs, and nothing does this (yet).
In a follow-up CL, we will set CreateProcessArgs.MountNamespace when creating a
new container inside runsc.
Note that "MountNamespace" is a poor term for this thing. It's more like a
distinct VFS tree. When we get around to adding real mount namespaces, this
will need a better naem.
PiperOrigin-RevId: 254009310
Test fails because it's reading 4KB instead of the
expected 64KB. Changed the test to read pipe buffer
size instead of hardcode and added some logging in
case the reason for failure was not pipe buffer size.
PiperOrigin-RevId: 253916040
There were 3 string arguments that could be easily misplaced
and it makes it easier to add new arguments, especially for
Container that has dozens of callers.
PiperOrigin-RevId: 253872074
Test was calling Size() inside read and write loops. Size()
makes 2 syscalls to return the pipe size, making the test
do a lot more work than it should.
PiperOrigin-RevId: 253824690
sockets, pipes and other non-seekable file descriptors don't
use file.offset, so we don't need to update it.
With this change, we will be able to call file operations
without locking the file.mu mutex. This is already used for
pipes in the splice system call.
PiperOrigin-RevId: 253746644
$ bazel build runsc:runsc-debian
File ".../bazel_tools/tools/build_defs/pkg/make_deb.py", line 311,
in GetFlagValue:
flagvalue = flagvalue.decode('utf-8')
AttributeError: 'str' object has no attribute 'decode'
make_deb.py is incompatible with Python3.
https://github.com/bazelbuild/bazel/issues/8443
PiperOrigin-RevId: 253691923
The implementation is similar to linux where we track the number of bytes
consumed by the application to grow the receive buffer of a given TCP endpoint.
This ensures that the advertised window grows at a reasonable rate to accomodate
for the sender's rate and prevents large amounts of data being held in stack
buffers if the application is not actively reading or not reading fast enough.
The original paper that was used to implement the linux receive buffer auto-
tuning is available @ https://public.lanl.gov/radiant/pubs/drs/lacsi2001.pdf
NOTE: Linux does not implement DRS as defined in that paper, it's just a good
reference to understand the solution space.
Updates #230
PiperOrigin-RevId: 253168283
The deadlock can occur when both ends of a connected Unix socket which has
FIOASYNC enabled on at least one end are closed at the same time. One end
notifies that it is closing, calling (*waiter.Queue).Notify which takes
waiter.Queue.mu (as a read lock) and then calls (*FileAsync).Callback, which
takes FileAsync.mu. The other end tries to unregister for notifications by
calling (*FileAsync).Unregister, which takes FileAsync.mu and calls
(*waiter.Queue).EventUnregister which takes waiter.Queue.mu.
This is fixed by moving the calls to waiter.Waitable.EventRegister and
waiter.Waitable.EventUnregister outside of the protection of any mutex used
in (*FileAsync).Callback.
The new test is related, but does not cover this particular situation.
Also fix a data race on FileAsync.e.Callback. (*FileAsync).Callback checked
FileAsync.e.Callback under the protection of FileAsync.mu, but the waiter
calling (*FileAsync).Callback could not and did not. This is fixed by making
FileAsync.e.Callback immutable before passing it to the waiter for the first
time.
Fixes#346
PiperOrigin-RevId: 253138340
Andrei Vagin
Adin Scannell
Rahat Mahmood
Nicolas Lacasse
Fabricio Voznika
Bhasker Hariharan
Michael Pratt
Brad Burlage
Ayush Ranjan
Jamie Liu
Ian Gudger
Neel Natu
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