[PATCH V2 00/11] CXL: Process event logs

From: ira . weiny
Date: Wed Nov 30 2022 - 19:27:33 EST


From: Ira Weiny <ira.weiny@xxxxxxxxx>

Changes from V1
Address comments, from Jonathan, Dave, and Alison
Main comment was to allow for a full payload size number of
event records to be processed on each Get event cyle.
Pick up tags


This code has been tested with a newer qemu which allows for more events to be
returned at a time as well ad additional QMP event and interrupt injection.
Thos patches will follow once they have been cleaned up.

The series is in 5 parts:

0) Davidlohrs irq patch modified for 16 vectors
1) Base functionality
2) Parsing specific events (Dynamic Capacity Event Record is defered)
3) Event interrupt support
4) cxl-test infrastructure for basic tests

While I believe this entire series is ready to be merged I realize that the
interrupt support may still have some discussion around it. Therefor parts 1,
2, and 4 could be merged without irq support as cxl-test provides testing for
that. Interrupt testing requires Qemu but it too is fully tested and ready to
go.


Changes from RFC v2
Integrated Davidlohr's irq patch, allocate up to 16 vectors, and base
my irq support on modifications to that patch.
Smita
Check event status before reading each log.
Jonathan
Process more than 1 record at a time
Remove reserved fields
Steven
Prefix trace points with 'cxl_'
Davidlohr
PUll in his patch

Changes from RFC v1
Add event irqs
General simplification of the code.
Resolve field alignment questions
Update to rev 3.0 for comments and structures
Add reserved fields and output them

Event records inform the OS of various device events. Events are not needed
for any kernel operation but various user level software will want to track
events.

Add event reporting through the trace event mechanism. On driver load read and
clear all device events.

Enable all event logs for interrupts and process each log on interrupt.


TESTING:

Testing of this was performed with additions to QEMU in the following repo:

https://github.com/weiny2/qemu/tree/ira-cxl-events-latest

Changes to this repo are not finalized yet so I'm not posting those patches
right away. But there is enough functionality added to further test this.

1) event status register
2) additional event injection capabilities
3) Process more than 1 record at a time in Get/Clear mailbox commands

Davidlohr Bueso (1):
cxl/pci: Add generic MSI-X/MSI irq support

Ira Weiny (10):
cxl/mem: Implement Get Event Records command
cxl/mem: Implement Clear Event Records command
cxl/mem: Clear events on driver load
cxl/mem: Trace General Media Event Record
cxl/mem: Trace DRAM Event Record
cxl/mem: Trace Memory Module Event Record
cxl/mem: Wire up event interrupts
cxl/test: Add generic mock events
cxl/test: Add specific events
cxl/test: Simulate event log overflow

MAINTAINERS | 1 +
drivers/cxl/core/mbox.c | 260 +++++++++++++++++
drivers/cxl/cxl.h | 7 +
drivers/cxl/cxlmem.h | 188 ++++++++++++
drivers/cxl/cxlpci.h | 6 +
drivers/cxl/pci.c | 155 ++++++++++
include/trace/events/cxl.h | 486 ++++++++++++++++++++++++++++++++
include/uapi/linux/cxl_mem.h | 4 +
tools/testing/cxl/test/Kbuild | 2 +-
tools/testing/cxl/test/events.c | 362 ++++++++++++++++++++++++
tools/testing/cxl/test/events.h | 9 +
tools/testing/cxl/test/mem.c | 35 +++
12 files changed, 1514 insertions(+), 1 deletion(-)
create mode 100644 include/trace/events/cxl.h
create mode 100644 tools/testing/cxl/test/events.c
create mode 100644 tools/testing/cxl/test/events.h


base-commit: aae703b02f92bde9264366c545e87cec451de471
--
2.37.2