From: Chia-Yu Chang <chia-yu.chang(a)nokia-bell-labs.com>
Hello,
Please find the DualPI2 patch v21.
This patch serise adds DualPI Improved with a Square (DualPI2) with following features:
* Supports congestion controls that comply with the Prague requirements in RFC9331 (e.g. TCP-Prague)
* Coupled dual-queue that separates the L4S traffic in a low latency queue (L-queue), without harming remaining traffic that is scheduled in classic queue (C-queue) due to congestion-coupling using PI2 as defined in RFC9332
* Configurable overload strategies
* Use of sojourn time to reliably estimate queue delay
* Supports ECN L4S-identifier (IP.ECN==0b*1) to classify traffic into respective queues
For more details of DualPI2, please refer IETF RFC9332 (https://datatracker.ietf.org/doc/html/rfc9332).
Best regards,
Chia-Yu
---
v21 (02-Jul-2025)
- Replace STEP_THRESH and STEP_PACKETS with STEP_THRESH_PKTS and STEP_THRESH_US (Jakub Kicinski <kuba(a)kernel.org>)
- Move READ_ONCE and WRITE_ONCE to later DualPI2 patches (Jakub Kicinski <kuba(a)kernel.org>)
- Replace NLA_POLICY_FULL_RANGE with NLA_POLICY_RANGE (Jakub Kicinski <kuba(a)kernel.org>)
- Set extra error message for dualpi2_change (Jakub Kicinski <kuba(a)kernel.org>)
- Drop redundant else for better readability (Paolo Abeni <pabeni(a)redhat.com>)
- Replace step-thresh and step-packets with step-thresh-pkts and step-thresh-us (Jakub Kicinski <kuba(a)kernel.org>)
- Remove redundant name-prefix and simplify entries of dualpi2 enums (Jakub Kicinski <kuba(a)kernel.org>)
- Fix some typos and format issues of dualpi2 attributes
v20 (21-Jun-2025)
- Add one more commit to fix warning and style check on tdc.sh reported by shellcheck
- Remove double-prefixed of "tc_tc_dualpi2_attrs" in tc-user.h (Donald Hunter <donald.hunter(a)gmail.com>)
v19 (14-Jun-2025)
- Fix one typo in the comment of #1 (ALOK TIWARI <alok.a.tiwari(a)oracle.com>)
- Update commit message of #4 (ALOK TIWARI <alok.a.tiwari(a)oracle.com>)
- Wrap long lines of Documentation/netlink/specs/tc.yaml to within 80 characters (Jakub Kicinski <kuba(a)kernel.org>)
v18 (13-Jun-2025)
- Add the num of enum used by DualPI2 and fix name and name-prefix of DualPI2 enum and attribute
- Replace from_timer() with timer_container_of() (Pedro Tammela <pctammela(a)mojatatu.com>)
v17 (25-May-2025, Resent at 11-Jun-2025)
- Replace 0xffffffff with U32_MAX (Paolo Abeni <pabeni(a)redhat.com>)
- Use helper function qdisc_dequeue_internal() and add new helper function skb_apply_step() (Paolo Abeni <pabeni(a)redhat.com>)
- Add s64 casting when calculating the delta of the PI controller (Paolo Abeni <pabeni(a)redhat.com>)
- Change the drop reason into SKB_DROP_REASON_QDISC_CONGESTED for drop_early (Paolo Abeni <pabeni(a)redhat.com>)
- Modify the condition to remove the original skb when enqueuing multiple GSO segments (Paolo Abeni <pabeni(a)redhat.com>)
- Add READ_ONCE() in dualpi2_dump_stat() (Paolo Abeni <pabeni(a)redhat.com>)
- Add comments, brackets, and brackets for readability (Paolo Abeni <pabeni(a)redhat.com>)
v16 (16-MAy-2025)
- Add qdisc_lock() to dualpi2_timer() in dualpi2_timer (Paolo Abeni <pabeni(a)redhat.com>)
- Introduce convert_ns_to_usec() to convert usec to nsec without overflow in #1 (Paolo Abeni <pabeni(a)redhat.com>)
- Update convert_us_tonsec() to convert nsec to usec without overflow in #2 (Paolo Abeni <pabeni(a)redhat.com>)
- Add more descriptions with respect to DualPI2 in the cover ltter and add changelog in each patch (Paolo Abeni <pabeni(a)redhat.com>)
v15 (09-May-2025)
- Add enum of TCA_DUALPI2_ECN_MASK_CLA_ECT to remove potential leakeage in #1 (Simon Horman <horms(a)kernel.org>)
- Fix one typo in comment of #2
- Update tc.yaml in #5 to aligh with the updated enum of pkt_sched.h
v14 (05-May-2025)
- Modify tc.yaml: (1) Replace flags with enum and remove enum-as-flags, (2) Remove credit-queue in xstats, and (3) Change attribute types (Donald Hunter <donald.hun
- Add enum and fix the ordering of variables in pkt_sched.h to align with the modified tc.yaml (Donald Hunter <donald.hunter(a)gmail.com>)
- Add validators for DROP_OVERLOAD, DROP_EARLY, ECN_MASK, and SPLIT_GSO in sch_dualpi2.c (Donald Hunter <donald.hunter(a)gmail.com>)
- Update dualpi2.json to align with the updated variable order in pkt_sched.h
- Reorder patches (Donald Hunter <donald.hunter(a)gmail.com>)
v13 (26-Apr-2025)
- Use dashes in member names to follow YNL conventions in tc.yaml (Donald Hunter <donald.hunter(a)gmail.com>)
- Define enumerations separately for flags of drop-early, drop-overload, ecn-mask, credit-queue in tc.yaml (Donald Hunter <donald.hunter(a)gmail.com>)
- Change the types of split-gso and step-packets into flag in tc.yaml (Donald Hunter <donald.hunter(a)gmail.com>)
- Revert to u32/u8 types for tc-dualpi2-xstats members in tc.yaml (Donald Hunter <donald.hunter(a)gmail.com>)
- Add new test cases in tc-tests/qdiscs/dualpi2.json to cover all dualpi2 parameters (Donald Hunter <donald.hunter(a)gmail.com>)
- Change the type of TCA_DUALPI2_STEP_PACKETS into NLA_FLAG (Donald Hunter <donald.hunter(a)gmail.com>)
v12 (22-Apr-2025)
- Remove anonymous struct in sch_dualpi2.c (Paolo Abeni <pabeni(a)redhat.com>)
- Replace u32/u8 with uint and s32 with int in tc spec document (Paolo Abeni <pabeni(a)redhat.com>)
- Introduce get_memory_limit function to handle potential overflow when multipling limit with MTU (Paolo Abeni <pabeni(a)redhat.com>)
- Double the packet length to further include packet overhead in memory_limit (Paolo Abeni <pabeni(a)redhat.com>)
- Remove the check of qdisc_qlen(sch) when calling qdisc_tree_reduce_backlog (Paolo Abeni <pabeni(a)redhat.com>)
v11 (15-Apr-2025)
- Replace hstimer_init with hstimer_setup in sch_dualpi2.c
v10 (25-Mar-2025)
- Remove leftover include in include/linux/netdevice.h and anonymous struct in sch_dualpi2.c (Paolo Abeni <pabeni(a)redhat.com>)
- Use kfree_skb_reason() and add SKB_DROP_REASON_DUALPI2_STEP_DROP drop reason (Paolo Abeni <pabeni(a)redhat.com>)
- Split sch_dualpi2.c into 3 patches (and overall 5 patches): Struct definition & parsing, Dump stats & configuration, Enqueue/Dequeue (Paolo Abeni <pabeni(a)redhat.com>)
v9 (16-Mar-2025)
- Fix mem_usage error in previous version
- Add min_qlen_step to the dualpi2 attribute as the minimum queue length in number of packets in the L-queue to start step threshold marking.
In previous versions, this value was fixed to 2, so the step threshold was applied to mark packets in the L queue only when the queue length of the L queue was greater than or equal to 2 packets.
This will cause larger queuing delays for L4S traffic at low rates (<20Mbps). So we parameterize it and change the default value to 0.
Comparison of tcp_1down run 'HTB 20Mbit + DUALPI2 + 10ms base delay'
Old versions:
avg median # data pts
Ping (ms) ICMP : 11.55 11.70 ms 350
TCP upload avg : 18.96 N/A Mbits/s 350
TCP upload sum : 18.96 N/A Mbits/s 350
New version (v9):
avg median # data pts
Ping (ms) ICMP : 10.81 10.70 ms 350
TCP upload avg : 18.91 N/A Mbits/s 350
TCP upload sum : 18.91 N/A Mbits/s 350
Comparison of tcp_1down run 'HTB 10Mbit + DUALPI2 + 10ms base delay'
Old versions:
avg median # data pts
Ping (ms) ICMP : 12.61 12.80 ms 350
TCP upload avg : 9.48 N/A Mbits/s 350
TCP upload sum : 9.48 N/A Mbits/s 350
New version (v9):
avg median # data pts
Ping (ms) ICMP : 11.06 10.80 ms 350
TCP upload avg : 9.43 N/A Mbits/s 350
TCP upload sum : 9.43 N/A Mbits/s 350
Comparison of tcp_1down run 'HTB 10Mbit + DUALPI2 + 10ms base delay'
Old versions:
avg median # data pts
Ping (ms) ICMP : 40.86 37.45 ms 350
TCP upload avg : 0.88 N/A Mbits/s 350
TCP upload sum : 0.88 N/A Mbits/s 350
TCP upload::1 : 0.88 0.97 Mbits/s 350
New version (v9):
avg median # data pts
Ping (ms) ICMP : 11.07 10.40 ms 350
TCP upload avg : 0.55 N/A Mbits/s 350
TCP upload sum : 0.55 N/A Mbits/s 350
TCP upload::1 : 0.55 0.59 Mbits/s 350
v8 (11-Mar-2025)
- Fix warning messages in v7
v7 (07-Mar-2025)
- Separate into 3 patches to avoid mixing changes of documentation, selftest, and code. (Cong Wang <xiyou.wangcong(a)gmail.com>)
v6 (04-Mar-2025)
- Add modprobe for dulapi2 in tc-testing script tc-testing/tdc.sh (Jakub Kicinski <kuba(a)kernel.org>)
- Update test cases in dualpi2.json
- Update commit message
v5 (22-Feb-2025)
- A comparison was done between MQ + DUALPI2, MQ + FQ_PIE, MQ + FQ_CODEL:
Unshaped 1gigE with 4 download streams test:
- Summary of tcp_4down run 'MQ + FQ_CODEL':
avg median # data pts
Ping (ms) ICMP : 1.19 1.34 ms 349
TCP download avg : 235.42 N/A Mbits/s 349
TCP download sum : 941.68 N/A Mbits/s 349
TCP download::1 : 235.19 235.39 Mbits/s 349
TCP download::2 : 235.03 235.35 Mbits/s 349
TCP download::3 : 236.89 235.44 Mbits/s 349
TCP download::4 : 234.57 235.19 Mbits/s 349
- Summary of tcp_4down run 'MQ + FQ_PIE'
avg median # data pts
Ping (ms) ICMP : 1.21 1.37 ms 350
TCP download avg : 235.42 N/A Mbits/s 350
TCP download sum : 941.61 N/A Mbits/s 350
TCP download::1 : 232.54 233.13 Mbits/s 350
TCP download::2 : 232.52 232.80 Mbits/s 350
TCP download::3 : 233.14 233.78 Mbits/s 350
TCP download::4 : 243.41 241.48 Mbits/s 350
- Summary of tcp_4down run 'MQ + DUALPI2'
avg median # data pts
Ping (ms) ICMP : 1.19 1.34 ms 349
TCP download avg : 235.42 N/A Mbits/s 349
TCP download sum : 941.68 N/A Mbits/s 349
TCP download::1 : 235.19 235.39 Mbits/s 349
TCP download::2 : 235.03 235.35 Mbits/s 349
TCP download::3 : 236.89 235.44 Mbits/s 349
TCP download::4 : 234.57 235.19 Mbits/s 349
Unshaped 1gigE with 128 download streams test:
- Summary of tcp_128down run 'MQ + FQ_CODEL':
avg median # data pts
Ping (ms) ICMP : 1.88 1.86 ms 350
TCP download avg : 7.39 N/A Mbits/s 350
TCP download sum : 946.47 N/A Mbits/s 350
- Summary of tcp_128down run 'MQ + FQ_PIE':
avg median # data pts
Ping (ms) ICMP : 1.88 1.86 ms 350
TCP download avg : 7.39 N/A Mbits/s 350
TCP download sum : 946.47 N/A Mbits/s 350
- Summary of tcp_128down run 'MQ + DUALPI2':
avg median # data pts
Ping (ms) ICMP : 1.88 1.86 ms 350
TCP download avg : 7.39 N/A Mbits/s 350
TCP download sum : 946.47 N/A Mbits/s 350
Unshaped 10gigE with 4 download streams test:
- Summary of tcp_4down run 'MQ + FQ_CODEL':
avg median # data pts
Ping (ms) ICMP : 0.22 0.23 ms 350
TCP download avg : 2354.08 N/A Mbits/s 350
TCP download sum : 9416.31 N/A Mbits/s 350
TCP download::1 : 2353.65 2352.81 Mbits/s 350
TCP download::2 : 2354.54 2354.21 Mbits/s 350
TCP download::3 : 2353.56 2353.78 Mbits/s 350
TCP download::4 : 2354.56 2354.45 Mbits/s 350
- Summary of tcp_4down run 'MQ + FQ_PIE':
avg median # data pts
Ping (ms) ICMP : 0.20 0.19 ms 350
TCP download avg : 2354.76 N/A Mbits/s 350
TCP download sum : 9419.04 N/A Mbits/s 350
TCP download::1 : 2354.77 2353.89 Mbits/s 350
TCP download::2 : 2353.41 2354.29 Mbits/s 350
TCP download::3 : 2356.18 2354.19 Mbits/s 350
TCP download::4 : 2354.68 2353.15 Mbits/s 350
- Summary of tcp_4down run 'MQ + DUALPI2':
avg median # data pts
Ping (ms) ICMP : 0.24 0.24 ms 350
TCP download avg : 2354.11 N/A Mbits/s 350
TCP download sum : 9416.43 N/A Mbits/s 350
TCP download::1 : 2354.75 2353.93 Mbits/s 350
TCP download::2 : 2353.15 2353.75 Mbits/s 350
TCP download::3 : 2353.49 2353.72 Mbits/s 350
TCP download::4 : 2355.04 2353.73 Mbits/s 350
Unshaped 10gigE with 128 download streams test:
- Summary of tcp_128down run 'MQ + FQ_CODEL':
avg median # data pts
Ping (ms) ICMP : 7.57 8.69 ms 350
TCP download avg : 73.97 N/A Mbits/s 350
TCP download sum : 9467.82 N/A Mbits/s 350
- Summary of tcp_128down run 'MQ + FQ_PIE':
avg median # data pts
Ping (ms) ICMP : 7.82 8.91 ms 350
TCP download avg : 73.97 N/A Mbits/s 350
TCP download sum : 9468.42 N/A Mbits/s 350
- Summary of tcp_128down run 'MQ + DUALPI2':
avg median # data pts
Ping (ms) ICMP : 6.87 7.93 ms 350
TCP download avg : 73.95 N/A Mbits/s 350
TCP download sum : 9465.87 N/A Mbits/s 350
From the results shown above, we see small differences between combinations.
- Update commit message to include results of no_split_gso and split_gso (Dave Taht <dave.taht(a)gmail.com> and Paolo Abeni <pabeni(a)redhat.com>)
- Add memlimit in the dualpi2 attribute, and add memory_used, max_memory_used, memory_limit in dualpi2 stats (Dave Taht <dave.taht(a)gmail.com>)
- Update note in sch_dualpi2.c related to BBRv3 status (Dave Taht <dave.taht(a)gmail.com>)
- Update license identifier (Dave Taht <dave.taht(a)gmail.com>)
- Add selftest in tools/testing/selftests/tc-testing (Cong Wang <xiyou.wangcong(a)gmail.com>)
- Use netlink policies for parameter checks (Jamal Hadi Salim <jhs(a)mojatatu.com>)
- Modify texts & fix typos in Documentation/netlink/specs/tc.yaml (Dave Taht <dave.taht(a)gmail.com>)
- Add descriptions of packet counter statistics and the reset function of sch_dualpi2.c
- Fix step_thresh in packets
- Update code comments in sch_dualpi2.c
v4 (22-Oct-2024)
- Update statement in Kconfig for DualPI2 (Stephen Hemminger <stephen(a)networkplumber.org>)
- Put a blank line after #define in sch_dualpi2.c (Stephen Hemminger <stephen(a)networkplumber.org>)
- Fix line length warning.
v3 (19-Oct-2024)
- Fix compilaiton error
- Update Documentation/netlink/specs/tc.yaml (Jakub Kicinski <kuba(a)kernel.org>)
v2 (18-Oct-2024)
- Add Documentation/netlink/specs/tc.yaml (Jakub Kicinski <kuba(a)kernel.org>)
- Use dualpi2 instead of skb prefix (Jamal Hadi Salim <jhs(a)mojatatu.com>)
- Replace nla_parse_nested_deprecated with nla_parse_nested (Jamal Hadi Salim <jhs(a)mojatatu.com>)
- Fix line length warning
---
Chia-Yu Chang (5):
sched: Struct definition and parsing of dualpi2 qdisc
sched: Dump configuration and statistics of dualpi2 qdisc
selftests/tc-testing: Fix warning and style check on tdc.sh
selftests/tc-testing: Add selftests for qdisc DualPI2
Documentation: netlink: specs: tc: Add DualPI2 specification
Koen De Schepper (1):
sched: Add enqueue/dequeue of dualpi2 qdisc
Documentation/netlink/specs/tc.yaml | 151 ++-
include/net/dropreason-core.h | 6 +
include/uapi/linux/pkt_sched.h | 68 +
net/sched/Kconfig | 12 +
net/sched/Makefile | 1 +
net/sched/sch_dualpi2.c | 1171 +++++++++++++++++
tools/testing/selftests/tc-testing/config | 1 +
.../tc-testing/tc-tests/qdiscs/dualpi2.json | 254 ++++
tools/testing/selftests/tc-testing/tdc.sh | 6 +-
9 files changed, 1665 insertions(+), 5 deletions(-)
create mode 100644 net/sched/sch_dualpi2.c
create mode 100644 tools/testing/selftests/tc-testing/tc-tests/qdiscs/dualpi2.json
--
2.34.1
A few packets may still be sent and received during the termination of
the iperf processes. These late packets cause failures when they arrive
on queues expected to be empty.
Add a one second delay between repeated _send_traffic_check() calls in
rss_ctx tests to ensure such packets are processed before the next
traffic checks are performed.
Example failure observed:
Check failed 2 != 0 traffic on inactive queues (context 1):
[0, 0, 1, 1, 386385, 397196, 0, 0, 0, 0, ...]
Check failed 4 != 0 traffic on inactive queues (context 2):
[0, 0, 0, 0, 2, 2, 247152, 253013, 0, 0, ...]
Check failed 2 != 0 traffic on inactive queues (context 3):
[0, 0, 0, 0, 0, 0, 1, 1, 282434, 283070, ...]
Note: While the `noise` parameter could be used to tolerate these late
packets, it would be inappropriate here. `noise` tolerates far more
traffic than acceptable in this case, risking false positives.
Inactive queues are supposed to see zero traffic.
Fixes: 847aa551fa78 ("selftests: drv-net: rss_ctx: factor out send traffic and check")
Reviewed-by: Gal Pressman <gal(a)nvidia.com>
Reviewed-by: Carolina Jubran <cjubran(a)nvidia.com>
Signed-off-by: Nimrod Oren <noren(a)nvidia.com>
---
tools/testing/selftests/drivers/net/hw/rss_ctx.py | 3 +++
1 file changed, 3 insertions(+)
diff --git a/tools/testing/selftests/drivers/net/hw/rss_ctx.py b/tools/testing/selftests/drivers/net/hw/rss_ctx.py
index 7bb552f8b182..19be69227693 100755
--- a/tools/testing/selftests/drivers/net/hw/rss_ctx.py
+++ b/tools/testing/selftests/drivers/net/hw/rss_ctx.py
@@ -4,6 +4,7 @@
import datetime
import random
import re
+import time
from lib.py import ksft_run, ksft_pr, ksft_exit
from lib.py import ksft_eq, ksft_ne, ksft_ge, ksft_in, ksft_lt, ksft_true, ksft_raises
from lib.py import NetDrvEpEnv
@@ -492,6 +493,7 @@ def test_rss_context(cfg, ctx_cnt=1, create_with_cfg=None):
{ 'target': (2+i*2, 3+i*2),
'noise': (0, 1),
'empty': list(range(2, 2+i*2)) + list(range(4+i*2, 2+2*ctx_cnt)) })
+ time.sleep(1)
if requested_ctx_cnt != ctx_cnt:
raise KsftSkipEx(f"Tested only {ctx_cnt} contexts, wanted {requested_ctx_cnt}")
@@ -559,6 +561,7 @@ def test_rss_context_out_of_order(cfg, ctx_cnt=4):
}
_send_traffic_check(cfg, ports[i], f"context {i}", expected)
+ time.sleep(1)
# Use queues 0 and 1 for normal traffic
ethtool(f"-X {cfg.ifname} equal 2")
--
2.37.1
[All the precursor patches are merged now and AMD/RISCV/VTD conversions
are written]
Currently each of the iommu page table formats duplicates all of the logic
to maintain the page table and perform map/unmap/etc operations. There are
several different versions of the algorithms between all the different
formats. The io-pgtable system provides an interface to help isolate the
page table code from the iommu driver, but doesn't provide tools to
implement the common algorithms.
This makes it very hard to improve the state of the pagetable code under
the iommu domains as any proposed improvement needs to alter a large
number of different driver code paths. Combined with a lack of software
based testing this makes improvement in this area very hard.
iommufd wants several new page table operations:
- More efficient map/unmap operations, using iommufd's batching logic
- unmap that returns the physical addresses into a batch as it progresses
- cut that allows splitting areas so large pages can have holes
poked in them dynamically (ie guestmemfd hitless shared/private
transitions)
- More agressive freeing of table memory to avoid waste
- Fragmenting large pages so that dirty tracking can be more granular
- Reassembling large pages so that VMs can run at full IO performance
in migration/dirty tracking error flows
- KHO integration for kernel live upgrade
Together these are algorithmically complex enough to be a very significant
task to go and implement in all the page table formats we support. Just
the "server" focused drivers use almost all the formats (ARMv8 S1&S2 / x86
PAE / AMDv1 / VT-D SS / RISCV)
Instead of doing the duplicated work, this series takes the first step to
consolidate the algorithms into one places. In spirit it is similar to the
work Christoph did a few years back to pull the redundant get_user_pages()
implementations out of the arch code into core MM. This unlocked a great
deal of improvement in that space in the following years. I would like to
see the same benefit in iommu as well.
My first RFC showed a bigger picture with all most all formats and more
algorithms. This series reorganizes that to be narrowly focused on just
enough to convert the AMD driver to use the new mechanism.
kunit tests are provided that allow good testing of the algorithms and all
formats on x86, nothing is arch specific.
AMD is one of the simpler options as the HW is quite uniform with few
different options/bugs while still requiring the complicated contiguous
pages support. The HW also has a very simple range based invalidation
approach that is easy to implement.
The AMD v1 and AMD v2 page table formats are implemented bit for bit
identical to the current code, tested using a compare kunit test that
checks against the io-pgtable version (on github, see below).
Updating the AMD driver to replace the io-pgtable layer with the new stuff
is fairly straightforward now. The layering is fixed up in the new version
so that all the invalidation goes through function pointers.
Several small fixing patches have come out of this as I've been fixing the
problems that the test suite uncovers in the current code, and
implementing the fixed version in iommupt.
On performance, there is a quite wide variety of implementation designs
across all the drivers. Looking at some key performance across
the main formats:
iommu_map():
pgsz ,avg new,old ns, min new,old ns , min % (+ve is better)
2^12, 53,66 , 51,63 , 19.19 (AMDV1)
256*2^12, 386,1909 , 367,1795 , 79.79
256*2^21, 362,1633 , 355,1556 , 77.77
2^12, 56,62 , 52,59 , 11.11 (AMDv2)
256*2^12, 405,1355 , 357,1292 , 72.72
256*2^21, 393,1160 , 358,1114 , 67.67
2^12, 55,65 , 53,62 , 14.14 (VTD second stage)
256*2^12, 391,518 , 332,512 , 35.35
256*2^21, 383,635 , 336,624 , 46.46
2^12, 57,65 , 55,63 , 12.12 (ARM 64 bit)
256*2^12, 380,389 , 361,369 , 2.02
256*2^21, 358,419 , 345,400 , 13.13
iommu_unmap():
pgsz ,avg new,old ns, min new,old ns , min % (+ve is better)
2^12, 69,88 , 65,85 , 23.23 (AMDv1)
256*2^12, 353,6498 , 331,6029 , 94.94
256*2^21, 373,6014 , 360,5706 , 93.93
2^12, 71,72 , 66,69 , 4.04 (AMDv2)
256*2^12, 228,891 , 206,871 , 76.76
256*2^21, 254,721 , 245,711 , 65.65
2^12, 69,87 , 65,82 , 20.20 (VTD second stage)
256*2^12, 210,321 , 200,315 , 36.36
256*2^21, 255,349 , 238,342 , 30.30
2^12, 72,77 , 68,74 , 8.08 (ARM 64 bit)
256*2^12, 521,357 , 447,346 , -29.29
256*2^21, 489,358 , 433,345 , -25.25
* Above numbers include additional patches to remove the iommu_pgsize()
overheads. gcc 13.3.0, i7-12700
This version provides fairly consistent performance across formats. ARM
unmap performance is quite different because this version supports
contiguous pages and uses a very different algorithm for unmapping. Though
why it is so worse compared to AMDv1 I haven't figured out yet.
The per-format commits include a more detailed chart.
There is a second branch:
https://github.com/jgunthorpe/linux/commits/iommu_pt_all
Containing supporting work and future steps:
- ARM short descriptor (32 bit), ARM long descriptor (64 bit) formats
- RISCV format and RISCV conversion
https://github.com/jgunthorpe/linux/commits/iommu_pt_riscv
- Support for a DMA incoherent HW page table walker
- VT-D second stage format and VT-D conversion
https://github.com/jgunthorpe/linux/commits/iommu_pt_vtd
- DART v1 & v2 format
- Draft of a iommufd 'cut' operation to break down huge pages
- A compare test that checks the iommupt formats against the iopgtable
interface, including updating AMD to have a working iopgtable and patches
to make VT-D have an iopgtable for testing.
- A performance test to micro-benchmark map and unmap against iogptable
My strategy is to go one by one for the drivers:
- AMD driver conversion
- RISCV page table and driver
- Intel VT-D driver and VTDSS page table
- Flushing improvements for RISCV
- ARM SMMUv3
And concurrently work on the algorithm side:
- debugfs content dump, like VT-D has
- Cut support
- Increase/Decrease page size support
- map/unmap batching
- KHO
As we make more algorithm improvements the value to convert the drivers
increases.
This is on github: https://github.com/jgunthorpe/linux/commits/iommu_pt
v2:
- Rebase on v6.16-rc2
- s/PT_ENTRY_WORD_SIZE/PT_ITEM_WORD_SIZE/s to follow the language better
- Comment and documentation updates
- Add PT_TOP_PHYS_MASK to help manage alignment restrictions on the top
pointer
- Add missed force_aperture = true
- Make pt_iommu_deinit() take care of the not-yet-inited error case
internally as AMD/RISCV/VTD all shared this logic
- Change gather_range() into gather_range_pages() so it also deals with
the page list. This makes the following cache flushing series simpler
- Fix missed update of unmap->unmapped in some error cases
- Change clear_contig() to order the gather more logically
- Remove goto from the error handling in __map_range_leaf()
- s/log2_/oalog2_/ in places where the argument is an oaddr_t
- Pass the pts to pt_table_install64/32()
- Do not use SIGN_EXTEND for the AMDv2 page table because of Vasant's
information on how PASID 0 works.
v1: https://patch.msgid.link/r/0-v2-5c26bde5c22d+58b-iommu_pt_jgg@nvidia.com
- AMD driver only, many code changes
RFC: https://lore.kernel.org/all/0-v1-01fa10580981+1d-iommu_pt_jgg@nvidia.com/
Alejandro Jimenez (1):
iommu/amd: Use the generic iommu page table
Jason Gunthorpe (14):
genpt: Generic Page Table base API
genpt: Add Documentation/ files
iommupt: Add the basic structure of the iommu implementation
iommupt: Add the AMD IOMMU v1 page table format
iommupt: Add iova_to_phys op
iommupt: Add unmap_pages op
iommupt: Add map_pages op
iommupt: Add read_and_clear_dirty op
iommupt: Add a kunit test for Generic Page Table
iommupt: Add a mock pagetable format for iommufd selftest to use
iommufd: Change the selftest to use iommupt instead of xarray
iommupt: Add the x86 64 bit page table format
iommu/amd: Remove AMD io_pgtable support
iommupt: Add a kunit test for the IOMMU implementation
.clang-format | 1 +
Documentation/driver-api/generic_pt.rst | 140 ++
Documentation/driver-api/index.rst | 1 +
drivers/iommu/Kconfig | 2 +
drivers/iommu/Makefile | 1 +
drivers/iommu/amd/Kconfig | 5 +-
drivers/iommu/amd/Makefile | 2 +-
drivers/iommu/amd/amd_iommu.h | 1 -
drivers/iommu/amd/amd_iommu_types.h | 109 +-
drivers/iommu/amd/io_pgtable.c | 560 --------
drivers/iommu/amd/io_pgtable_v2.c | 370 ------
drivers/iommu/amd/iommu.c | 516 ++++----
drivers/iommu/generic_pt/.kunitconfig | 13 +
drivers/iommu/generic_pt/Kconfig | 72 ++
drivers/iommu/generic_pt/fmt/Makefile | 26 +
drivers/iommu/generic_pt/fmt/amdv1.h | 409 ++++++
drivers/iommu/generic_pt/fmt/defs_amdv1.h | 21 +
drivers/iommu/generic_pt/fmt/defs_x86_64.h | 21 +
drivers/iommu/generic_pt/fmt/iommu_amdv1.c | 15 +
drivers/iommu/generic_pt/fmt/iommu_mock.c | 10 +
drivers/iommu/generic_pt/fmt/iommu_template.h | 48 +
drivers/iommu/generic_pt/fmt/iommu_x86_64.c | 11 +
drivers/iommu/generic_pt/fmt/x86_64.h | 248 ++++
drivers/iommu/generic_pt/iommu_pt.h | 1150 +++++++++++++++++
drivers/iommu/generic_pt/kunit_generic_pt.h | 717 ++++++++++
drivers/iommu/generic_pt/kunit_iommu.h | 183 +++
drivers/iommu/generic_pt/kunit_iommu_pt.h | 451 +++++++
drivers/iommu/generic_pt/pt_common.h | 354 +++++
drivers/iommu/generic_pt/pt_defs.h | 323 +++++
drivers/iommu/generic_pt/pt_fmt_defaults.h | 193 +++
drivers/iommu/generic_pt/pt_iter.h | 640 +++++++++
drivers/iommu/generic_pt/pt_log2.h | 130 ++
drivers/iommu/io-pgtable.c | 4 -
drivers/iommu/iommufd/Kconfig | 1 +
drivers/iommu/iommufd/iommufd_test.h | 11 +-
drivers/iommu/iommufd/selftest.c | 439 +++----
include/linux/generic_pt/common.h | 166 +++
include/linux/generic_pt/iommu.h | 270 ++++
include/linux/io-pgtable.h | 2 -
tools/testing/selftests/iommu/iommufd.c | 60 +-
tools/testing/selftests/iommu/iommufd_utils.h | 12 +
41 files changed, 6119 insertions(+), 1589 deletions(-)
create mode 100644 Documentation/driver-api/generic_pt.rst
delete mode 100644 drivers/iommu/amd/io_pgtable.c
delete mode 100644 drivers/iommu/amd/io_pgtable_v2.c
create mode 100644 drivers/iommu/generic_pt/.kunitconfig
create mode 100644 drivers/iommu/generic_pt/Kconfig
create mode 100644 drivers/iommu/generic_pt/fmt/Makefile
create mode 100644 drivers/iommu/generic_pt/fmt/amdv1.h
create mode 100644 drivers/iommu/generic_pt/fmt/defs_amdv1.h
create mode 100644 drivers/iommu/generic_pt/fmt/defs_x86_64.h
create mode 100644 drivers/iommu/generic_pt/fmt/iommu_amdv1.c
create mode 100644 drivers/iommu/generic_pt/fmt/iommu_mock.c
create mode 100644 drivers/iommu/generic_pt/fmt/iommu_template.h
create mode 100644 drivers/iommu/generic_pt/fmt/iommu_x86_64.c
create mode 100644 drivers/iommu/generic_pt/fmt/x86_64.h
create mode 100644 drivers/iommu/generic_pt/iommu_pt.h
create mode 100644 drivers/iommu/generic_pt/kunit_generic_pt.h
create mode 100644 drivers/iommu/generic_pt/kunit_iommu.h
create mode 100644 drivers/iommu/generic_pt/kunit_iommu_pt.h
create mode 100644 drivers/iommu/generic_pt/pt_common.h
create mode 100644 drivers/iommu/generic_pt/pt_defs.h
create mode 100644 drivers/iommu/generic_pt/pt_fmt_defaults.h
create mode 100644 drivers/iommu/generic_pt/pt_iter.h
create mode 100644 drivers/iommu/generic_pt/pt_log2.h
create mode 100644 include/linux/generic_pt/common.h
create mode 100644 include/linux/generic_pt/iommu.h
base-commit: cd76b0248a38645a3e3f8ca4a48bffc591e9da19
--
2.43.0
On Tue, 8 Jul 2025 23:13:01 +0530 Suresh Chandrappa <suresh.k.chandrappa(a)gmail.com> wrote:
> Hi Joshua,
>
> Thanks for the feedback! In the first patch, both shmem and mmap operations
> are present, but I hadn’t introduced any logic to distinguish between them
> yet. That distinction is added in the second patch through a new API.
Hi Suresh,
Yes, this makes sense to me. I think what I was getting at was that we could
still make a conditional statement like
if (type == FILE_SHMEM)
ksft_print_msg("Unable to create shmem file.\n")'
else if (type == FILE_MMAP)
ksft_print_msg("Unable to create mmap file.\n");
(or use a switch statement)
...
And just refactor it in patch 2, as opposed to changing the behavior.
But this is mostly a nit. If you are planning to merge both patches in one
patch in the next version, then all of these comments shouldn't matter : -)
Looking forward to the next version, have a great day!
Joshua
Sent using hkml (https://github.com/sjp38/hackermail)
With joint effort from the upstream KVM community, we come up with the
4th version of mediated vPMU for x86. We have made the following changes
on top of the previous RFC v3.
v3 -> v4
- Rebase whole patchset on 6.14-rc3 base.
- Address Peter's comments on Perf part.
- Address Sean's comments on KVM part.
* Change key word "passthrough" to "mediated" in all patches
* Change static enabling to user space dynamic enabling via KVM_CAP_PMU_CAPABILITY.
* Only support GLOBAL_CTRL save/restore with VMCS exec_ctrl, drop the MSR
save/retore list support for GLOBAL_CTRL, thus the support of mediated
vPMU is constrained to SapphireRapids and later CPUs on Intel side.
* Merge some small changes into a single patch.
- Address Sandipan's comment on invalid pmu pointer.
- Add back "eventsel_hw" and "fixed_ctr_ctrl_hw" to avoid to directly
manipulate pmc->eventsel and pmu->fixed_ctr_ctrl.
Testing (Intel side):
- Perf-based legacy vPMU (force emulation on/off)
* Kselftests pmu_counters_test, pmu_event_filter_test and
vmx_pmu_caps_test pass.
* KUT PMU tests pmu, pmu_lbr, pmu_pebs pass.
* Basic perf counting/sampling tests in 3 scenarios, guest-only,
host-only and host-guest coexistence all pass.
- Mediated vPMU (force emulation on/off)
* Kselftests pmu_counters_test, pmu_event_filter_test and
vmx_pmu_caps_test pass.
* KUT PMU tests pmu, pmu_lbr, pmu_pebs pass.
* Basic perf counting/sampling tests in 3 scenarios, guest-only,
host-only and host-guest coexistence all pass.
- Failures. All above tests passed on Intel Granite Rapids as well
except a failure on KUT/pmu_pebs.
* GP counter 0 (0xfffffffffffe): PEBS record (written seq 0)
is verified (including size, counters and cfg).
* The pebs_data_cfg (0xb500000000) doesn't match with the
effective MSR_PEBS_DATA_CFG (0x0).
* This failure has nothing to do with this mediated vPMU patch set. The
failure is caused by Granite Rapids supported timed PEBS which needs
extra support on Qemu and KUT/pmu_pebs. These extra support would be
sent in separate patches later.
Testing (AMD side):
- Kselftests pmu_counters_test, pmu_event_filter_test and
vmx_pmu_caps_test all pass
- legacy guest with KUT/pmu:
* qmeu option: -cpu host, -perfctr-core
* when set force_emulation_prefix=1, passes
* when set force_emulation_prefix=0, passes
- perfmon-v1 guest with KUT/pmu:
* qmeu option: -cpu host, -perfmon-v2
* when set force_emulation_prefix=1, passes
* when set force_emulation_prefix=0, passes
- perfmon-v2 guest with KUT/pmu:
* qmeu option: -cpu host
* when set force_emulation_prefix=1, passes
* when set force_emulation_prefix=0, passes
- perf_fuzzer (perfmon-v2):
* fails with soft lockup in guest in current version.
* culprit could be between 6.13 ~ 6.14-rc3 within KVM
* Series tested on 6.12 and 6.13 without issue.
Note: a QEMU series is needed to run mediated vPMU v4:
- https://lore.kernel.org/all/20250324123712.34096-1-dapeng1.mi@linux.intel.c…
History:
- RFC v3: https://lore.kernel.org/all/20240801045907.4010984-1-mizhang@google.com/
- RFC v2: https://lore.kernel.org/all/20240506053020.3911940-1-mizhang@google.com/
- RFC v1: https://lore.kernel.org/all/20240126085444.324918-1-xiong.y.zhang@linux.int…
Dapeng Mi (18):
KVM: x86/pmu: Introduce enable_mediated_pmu global parameter
KVM: x86/pmu: Check PMU cpuid configuration from user space
KVM: x86: Rename vmx_vmentry/vmexit_ctrl() helpers
KVM: x86/pmu: Add perf_capabilities field in struct kvm_host_values{}
KVM: x86/pmu: Move PMU_CAP_{FW_WRITES,LBR_FMT} into msr-index.h header
KVM: VMX: Add macros to wrap around
{secondary,tertiary}_exec_controls_changebit()
KVM: x86/pmu: Check if mediated vPMU can intercept rdpmc
KVM: x86/pmu/vmx: Save/load guest IA32_PERF_GLOBAL_CTRL with
vm_exit/entry_ctrl
KVM: x86/pmu: Optimize intel/amd_pmu_refresh() helpers
KVM: x86/pmu: Setup PMU MSRs' interception mode
KVM: x86/pmu: Handle PMU MSRs interception and event filtering
KVM: x86/pmu: Switch host/guest PMU context at vm-exit/vm-entry
KVM: x86/pmu: Handle emulated instruction for mediated vPMU
KVM: nVMX: Add macros to simplify nested MSR interception setting
KVM: selftests: Add mediated vPMU supported for pmu tests
KVM: Selftests: Support mediated vPMU for vmx_pmu_caps_test
KVM: Selftests: Fix pmu_counters_test error for mediated vPMU
KVM: x86/pmu: Expose enable_mediated_pmu parameter to user space
Kan Liang (8):
perf: Support get/put mediated PMU interfaces
perf: Skip pmu_ctx based on event_type
perf: Clean up perf ctx time
perf: Add a EVENT_GUEST flag
perf: Add generic exclude_guest support
perf: Add switch_guest_ctx() interface
perf/x86: Support switch_guest_ctx interface
perf/x86/intel: Support PERF_PMU_CAP_MEDIATED_VPMU
Mingwei Zhang (5):
perf/x86: Forbid PMI handler when guest own PMU
perf/x86/core: Plumb mediated PMU capability from x86_pmu to
x86_pmu_cap
KVM: x86/pmu: Exclude PMU MSRs in vmx_get_passthrough_msr_slot()
KVM: x86/pmu: introduce eventsel_hw to prepare for pmu event filtering
KVM: nVMX: Add nested virtualization support for mediated PMU
Sandipan Das (4):
perf/x86/core: Do not set bit width for unavailable counters
KVM: x86/pmu: Add AMD PMU registers to direct access list
KVM: x86/pmu/svm: Set GuestOnly bit and clear HostOnly bit when guest
write to event selectors
perf/x86/amd: Support PERF_PMU_CAP_MEDIATED_VPMU for AMD host
Xiong Zhang (3):
x86/irq: Factor out common code for installing kvm irq handler
perf: core/x86: Register a new vector for KVM GUEST PMI
KVM: x86/pmu: Register KVM_GUEST_PMI_VECTOR handler
arch/x86/events/amd/core.c | 2 +
arch/x86/events/core.c | 40 +-
arch/x86/events/intel/core.c | 5 +
arch/x86/include/asm/hardirq.h | 1 +
arch/x86/include/asm/idtentry.h | 1 +
arch/x86/include/asm/irq.h | 2 +-
arch/x86/include/asm/irq_vectors.h | 5 +-
arch/x86/include/asm/kvm-x86-pmu-ops.h | 2 +
arch/x86/include/asm/kvm_host.h | 10 +
arch/x86/include/asm/msr-index.h | 18 +-
arch/x86/include/asm/perf_event.h | 1 +
arch/x86/include/asm/vmx.h | 1 +
arch/x86/kernel/idt.c | 1 +
arch/x86/kernel/irq.c | 39 +-
arch/x86/kvm/cpuid.c | 15 +
arch/x86/kvm/pmu.c | 254 ++++++++-
arch/x86/kvm/pmu.h | 45 ++
arch/x86/kvm/svm/pmu.c | 148 ++++-
arch/x86/kvm/svm/svm.c | 26 +
arch/x86/kvm/svm/svm.h | 2 +-
arch/x86/kvm/vmx/capabilities.h | 11 +-
arch/x86/kvm/vmx/nested.c | 68 ++-
arch/x86/kvm/vmx/pmu_intel.c | 224 ++++++--
arch/x86/kvm/vmx/vmx.c | 89 +--
arch/x86/kvm/vmx/vmx.h | 11 +-
arch/x86/kvm/x86.c | 63 ++-
arch/x86/kvm/x86.h | 2 +
include/linux/perf_event.h | 47 +-
kernel/events/core.c | 519 ++++++++++++++----
.../beauty/arch/x86/include/asm/irq_vectors.h | 5 +-
.../selftests/kvm/include/kvm_test_harness.h | 13 +
.../testing/selftests/kvm/include/kvm_util.h | 3 +
.../selftests/kvm/include/x86/processor.h | 8 +
tools/testing/selftests/kvm/lib/kvm_util.c | 23 +
.../selftests/kvm/x86/pmu_counters_test.c | 24 +-
.../selftests/kvm/x86/pmu_event_filter_test.c | 8 +-
.../selftests/kvm/x86/vmx_pmu_caps_test.c | 2 +-
37 files changed, 1480 insertions(+), 258 deletions(-)
base-commit: 0ad2507d5d93f39619fc42372c347d6006b64319
--
2.49.0.395.g12beb8f557-goog
Hi everyone,
Here's a V2 for the netdevsim PHY support, including a bugfix for
NETDEVSIM=m as well as a round of shellcheck cleanups for
ethtool-phy.sh.
The idea of this series is to allow attaching virtual PHY devices to
netdevsim, so that we can test PHY-related ethtool commands. This can be
extended in the future for phylib testing as well.
V1: https://lore.kernel.org/netdev/20250702082806.706973-1-maxime.chevallier@bo…
Maxime Chevallier (3):
net: netdevsim: Add PHY support in netdevsim
selftests: ethtool: Drop the unused old_netdevs variable
selftests: ethtool: Introduce ethernet PHY selftests on netdevsim
drivers/net/netdevsim/Makefile | 4 +
drivers/net/netdevsim/dev.c | 2 +
drivers/net/netdevsim/netdev.c | 8 +
drivers/net/netdevsim/netdevsim.h | 25 ++
drivers/net/netdevsim/phy.c | 398 ++++++++++++++++++
.../selftests/drivers/net/netdevsim/config | 1 +
.../drivers/net/netdevsim/ethtool-common.sh | 19 +-
.../drivers/net/netdevsim/ethtool-phy.sh | 64 +++
8 files changed, 518 insertions(+), 3 deletions(-)
create mode 100644 drivers/net/netdevsim/phy.c
create mode 100755 tools/testing/selftests/drivers/net/netdevsim/ethtool-phy.sh
--
2.49.0
┌────────────┐ ┌───────────────────────────────────┐ ┌────────────────┐
│ │ │ │ │ │
│ │ │ PCI Endpoint │ │ PCI Host │
│ │ │ │ │ │
│ │◄──┤ 1.platform_msi_domain_alloc_irqs()│ │ │
│ │ │ │ │ │
│ MSI ├──►│ 2.write_msi_msg() ├──►├─BAR<n> │
│ Controller │ │ update doorbell register address│ │ │
│ │ │ for BAR │ │ │
│ │ │ │ │ 3. Write BAR<n>│
│ │◄──┼───────────────────────────────────┼───┤ │
│ │ │ │ │ │
│ ├──►│ 4.Irq Handle │ │ │
│ │ │ │ │ │
│ │ │ │ │ │
└────────────┘ └───────────────────────────────────┘ └────────────────┘
This patches based on old https://lore.kernel.org/imx/20221124055036.1630573-1-Frank.Li@nxp.com/
Original patch only target to vntb driver. But actually it is common
method.
This patches add new API to pci-epf-core, so any EP driver can use it.
Previous v2 discussion here.
https://lore.kernel.org/imx/20230911220920.1817033-1-Frank.Li@nxp.com/
Changes in v19:
- irq part already in v6.16-rc1, only missed pcie/dts part
- rebase to v6.16-rc1
- update commit message for patch IMMUTABLE check.
- Link to v18: https://lore.kernel.org/r/20250414-ep-msi-v18-0-f69b49917464@nxp.com
Changes in v18:
- pci-ep.yaml: sort property order, fix maxvalue to 0x7ffff for msi-map-mask and
iommu-map-mask
- Link to v17: https://lore.kernel.org/r/20250407-ep-msi-v17-0-633ab45a31d0@nxp.com
Changes in v17:
- move document part to pci-ep.yaml
- Link to v16: https://lore.kernel.org/r/20250404-ep-msi-v16-0-d4919d68c0d0@nxp.com
Changes in v16:
- remove arm64: dts: imx95-19x19-evk: Add PCIe1 endpoint function overlay file
because there are better patches, which under review.
- Add document for pcie-ep msi-map usage
- other change to see each patch's change log
About IMMUTABLE (No change for this part, tglx provide feedback)
> - This IMMUTABLE thing serves no purpose, because you don't randomly
> plug this end-point block on any MSI controller. They come as part
> of an SoC.
"Yes and no. The problem is that the EP implementation is meant to be a
generic library and while GIC-ITS guarantees immutability of the
address/data pair after setup, there are architectures (x86, loongson,
riscv) where the base MSI controller does not and immutability is only
achieved when interrupt remapping is enabled. The latter can be disabled
at boot-time and then the EP implementation becomes a lottery across
affinity changes.
That was my concern about this library implementation and that's why I
asked for a mechanism to ensure that the underlying irqdomain provides a
immutable address/data pair.
So it does not matter for GIC-ITS, but in the larger picture it matters.
Thanks,
tglx
"
So it does not matter for GIC-ITS, but in the larger picture it matters.
- Link to v15: https://lore.kernel.org/r/20250211-ep-msi-v15-0-bcacc1f2b1a9@nxp.com
Changes in v15:
- rebase to v6.14-rc1
- fix build issue find by kernel test robot
- Link to v14: https://lore.kernel.org/r/20250207-ep-msi-v14-0-9671b136f2b8@nxp.com
Changes in v14:
Marc Zyngier raised concerns about adding DOMAIN_BUS_DEVICE_PCI_EP_MSI. As
a result, the approach has been reverted to the v9 method. However, there
are several improvements:
MSI now supports msi-map in addition to msi-parent.
- The struct device: id is used as the endpoint function (EPF) device
identity to map to the stream ID (sideband information).
- The EPC device tree source (DTS) utilizes msi-map to provide such
information.
- The EPF device's of_node is set to the EPC controller’s node. This
approach is commonly used for multi-function device (MFD) platform child
devices, allowing them to inherit properties from the MFD device’s DTS,
such as reset-cells and gpio-cells. This method is well-suited for the
current case, as the EPF is inherently created/binded to the EPC and
should inherit the EPC’s DTS node properties.
Additionally:
Since the basic IMX95 LUT support has already been merged into the
mainline, a DTS and driver increment patch is added to complete the
solution. The patch is rebased onto the latest linux-next tree and
aligned with the new pcitest framework.
- Link to v13: https://lore.kernel.org/r/20241218-ep-msi-v13-0-646e2192dc24@nxp.com
Changes in v13:
- Change to use DOMAIN_BUS_PCI_DEVICE_EP_MSI
- Change request id as func | vfunc << 3
- Remove IRQ_DOMAIN_MSI_IMMUTABLE
Thomas Gleixner:
I hope capture all your points in review comments. If missed, let me know.
- Link to v12: https://lore.kernel.org/r/20241211-ep-msi-v12-0-33d4532fa520@nxp.com
Changes in v12:
- Change to use IRQ_DOMAIN_MSI_IMMUTABLE and add help function
irq_domain_msi_is_immuatble().
- split PCI: endpoint: pci-ep-msi: Add MSI address/data pair mutable check to 3 patches
- Link to v11: https://lore.kernel.org/r/20241209-ep-msi-v11-0-7434fa8397bd@nxp.com
Changes in v11:
- Change to use MSI_FLAG_MSG_IMMUTABLE
- Link to v10: https://lore.kernel.org/r/20241204-ep-msi-v10-0-87c378dbcd6d@nxp.com
Changes in v10:
Thomas Gleixner:
There are big change in pci-ep-msi.c. I am sure if go on the
corrent path. The key improvement is remove only 1 function devices's
limitation.
I use new patch for imutable check, which relative additional
feature compared to base enablement patch.
- Remove patch Add msi_remove_device_irq_domain() in platform_device_msi_free_irqs_all()
- Add new patch irqchip/gic-v3-its: Avoid overwriting msi_prepare callback if provided by msi_domain_info
- Remove only support 1 endpoint function limiation.
- Create one MSI domain for each endpoint function devices.
- Use "msi-map" in pci ep controler node, instead of of msi-parent. first
argument is
(func_no << 8 | vfunc_no)
- Link to v9: https://lore.kernel.org/r/20241203-ep-msi-v9-0-a60dbc3f15dd@nxp.com
Changes in v9
- Add patch platform-msi: Add msi_remove_device_irq_domain() in platform_device_msi_free_irqs_all()
- Remove patch PCI: endpoint: Add pci_epc_get_fn() API for customizable filtering
- Remove API pci_epf_align_inbound_addr_lo_hi
- Move doorbell_alloc in to doorbell_enable function.
- Link to v8: https://lore.kernel.org/r/20241116-ep-msi-v8-0-6f1f68ffd1bb@nxp.com
Changes in v8:
- update helper function name to pci_epf_align_inbound_addr()
- Link to v7: https://lore.kernel.org/r/20241114-ep-msi-v7-0-d4ac7aafbd2c@nxp.com
Changes in v7:
- Add helper function pci_epf_align_addr();
- Link to v6: https://lore.kernel.org/r/20241112-ep-msi-v6-0-45f9722e3c2a@nxp.com
Changes in v6:
- change doorbell_addr to doorbell_offset
- use round_down()
- add Niklas's test by tag
- rebase to pci/endpoint
- Link to v5: https://lore.kernel.org/r/20241108-ep-msi-v5-0-a14951c0d007@nxp.com
Changes in v5:
- Move request_irq to epf test function driver for more flexiable user case
- Add fixed size bar handler
- Some minor improvememtn to see each patches's changelog.
- Link to v4: https://lore.kernel.org/r/20241031-ep-msi-v4-0-717da2d99b28@nxp.com
Changes in v4:
- Remove patch genirq/msi: Add cleanup guard define for msi_lock_descs()/msi_unlock_descs()
- Use new method to avoid compatible problem.
Add new command DOORBELL_ENABLE and DOORBELL_DISABLE.
pcitest -B send DOORBELL_ENABLE first, EP test function driver try to
remap one of BAR_N (except test register bar) to ITS MSI MMIO space. Old
driver don't support new command, so failure return, not side effect.
After test, DOORBELL_DISABLE command send out to recover original map, so
pcitest bar test can pass as normal.
- Other detail change see each patches's change log
- Link to v3: https://lore.kernel.org/r/20241015-ep-msi-v3-0-cedc89a16c1a@nxp.com
Change from v2 to v3
- Fixed manivannan's comments
- Move common part to pci-ep-msi.c and pci-ep-msi.h
- rebase to 6.12-rc1
- use RevID to distingiush old version
mkdir /sys/kernel/config/pci_ep/functions/pci_epf_test/func1
echo 16 > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/msi_interrupts
echo 0x080c > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/deviceid
echo 0x1957 > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/vendorid
echo 1 > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/revid
^^^^^^ to enable platform msi support.
ln -s /sys/kernel/config/pci_ep/functions/pci_epf_test/func1 /sys/kernel/config/pci_ep/controllers/4c380000.pcie-ep
- use new device ID, which identify support doorbell to avoid broken
compatility.
Enable doorbell support only for PCI_DEVICE_ID_IMX8_DB, while other devices
keep the same behavior as before.
EP side RC with old driver RC with new driver
PCI_DEVICE_ID_IMX8_DB no probe doorbell enabled
Other device ID doorbell disabled* doorbell disabled*
* Behavior remains unchanged.
Change from v1 to v2
- Add missed patch for endpont/pci-epf-test.c
- Move alloc and free to epc driver from epf.
- Provide general help function for EPC driver to alloc platform msi irq.
- Fixed manivannan's comments.
Signed-off-by: Frank Li <Frank.Li(a)nxp.com>
---
Frank Li (10):
PCI: endpoint: Set ID and of_node for function driver
PCI: endpoint: Add RC-to-EP doorbell support using platform MSI controller
PCI: endpoint: pci-ep-msi: Add MSI address/data pair mutable check
PCI: endpoint: Add pci_epf_align_inbound_addr() helper for address alignment
PCI: endpoint: pci-epf-test: Add doorbell test support
misc: pci_endpoint_test: Add doorbell test case
selftests: pci_endpoint: Add doorbell test case
pci: imx6: Add helper function imx_pcie_add_lut_by_rid()
pci: imx6: Add LUT setting for MSI/IOMMU in Endpoint mode
arm64: dts: imx95: Add msi-map for pci-ep device
arch/arm64/boot/dts/freescale/imx95.dtsi | 1 +
drivers/misc/pci_endpoint_test.c | 82 ++++++++++++
drivers/pci/controller/dwc/pci-imx6.c | 25 ++--
drivers/pci/endpoint/Makefile | 1 +
drivers/pci/endpoint/functions/pci-epf-test.c | 142 +++++++++++++++++++++
drivers/pci/endpoint/pci-ep-msi.c | 90 +++++++++++++
drivers/pci/endpoint/pci-epf-core.c | 48 +++++++
include/linux/pci-ep-msi.h | 28 ++++
include/linux/pci-epf.h | 21 +++
include/uapi/linux/pcitest.h | 1 +
.../selftests/pci_endpoint/pci_endpoint_test.c | 28 ++++
11 files changed, 459 insertions(+), 8 deletions(-)
---
base-commit: 19272b37aa4f83ca52bdf9c16d5d81bdd1354494
change-id: 20241010-ep-msi-8b4cab33b1be
Best regards,
---
Frank Li <Frank.Li(a)nxp.com>