Commit Graph

4 Commits

Author SHA1 Message Date
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Dean Michael Berris e8c650ab12 [XRay] Fix TSC and atomic custom/typed event accounting
Summary:
This is a follow-on change to D53858 which turns out to have had a TSC
accounting bug when writing out function exit records in FDR mode.

This change adds a number of tests to ensure that:

- We are handling the delta between the exit TSC and the last TSC we've
  seen.

- We are writing the custom event and typed event records as a single
  update to the buffer extents.

- We are able to catch boundary conditions when loading FDR logs.

We introduce a TSC matcher to the test helpers, which we use in the
testing/verification of the TSC accounting change.

Reviewers: mboerger

Subscribers: mgorny, hiraditya, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D53967

llvm-svn: 345905
2018-11-01 22:57:50 +00:00
Dean Michael Berris ebfbf89000 [XRay] Handle allocator exhaustion in segmented array
Summary:
This change allows us to handle allocator exhaustion properly in the
segmented array implementation. Before this change, we relied on the
caller of the `trim` function to provide a valid number of elements to
trim. This change allows us to do the right thing in case the elements
to trim is greater than the size of the container.

Reviewers: mboerger, eizan

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D53484

llvm-svn: 344880
2018-10-22 02:11:27 +00:00
Dean Michael Berris 3c01508409 [XRay][compiler-rt] FDR Mode Controller
Summary:
This change implements a controller for abstracting away the details of
what happens when tracing with FDR mode. This controller type allows us
to test in isolation the various cases where we're encountering function
entry, exit, and other kinds of events we are handling when FDR mode is
enabled.

This change introduces a number of testing facilities we've needed to
better support expressing the conditions we need for the unit tests. We
leave some TODOs for moving those utilities into the LLVM project,
sitting in the `Testing` library, to make matching conditions on XRay
`Trace` instances through googlemock more manageable and declarative.

We don't wire in the controller right away, to allow us to incrementally
update the implementation(s) as we increase testing coverage of the
controller type. There's a need to re-think the way we're managing
buffers in a multi-threaded environment, which is more invasive than
this implementation.

This step in the process allows us to encode our assumptions in the
implementation of the controller, and then evolve the buffer queue
implementation to support generational buffer management to ensure we
can continue to support the cases we're already supporting with the
controller.

Reviewers: mboerger, eizan

Subscribers: mgorny, llvm-commits, jfb

Differential Revision: https://reviews.llvm.org/D52588

llvm-svn: 344488
2018-10-15 02:57:06 +00:00