The pattern of checking nocb_defer_wakeup and deleting the timer is
duplicated in __wake_nocb_gp() and nocb_gp_wait(). Extract this into a
common helper function nocb_defer_wakeup_cancel().
This removes code duplication and makes it easier to maintain.
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
During callback overload (exceeding qhimark), the NOCB code attempts
opportunistic advancement via rcu_advance_cbs_nowake(). Analysis shows
this code path is practically unreachable and serves no useful purpose.
Testing with 300,000 callback floods showed:
- 30 overload conditions triggered
- 0 advancements actually occurred
While a theoretical window exists where this code could execute (e.g.,
vCPU preemption between gp_seq update and rcu_nocb_gp_cleanup()), even
if it did, the advancement would be redundant. The rcuog kthread must
still run to wake the rcuoc callback thread - we would just be
duplicating work that rcuog will perform when it finally gets to run.
Since this path provides no meaningful benefit and extensive testing
confirms it is never useful, remove it entirely.
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
The WakeOvfIsDeferred code path in __call_rcu_nocb_wake() attempts to
wake rcuog when the callback count exceeds qhimark and callbacks aren't
done with their GP (newly queued or awaiting GP). However, a lot of
testing proves this wake is always redundant or useless.
In the flooding case, rcuog is always waiting for a GP to finish. So
waking up the rcuog thread is pointless. The timer wakeup adds overhead,
rcuog simply wakes up and goes back to sleep achieving nothing.
This path also adds a full memory barrier, and additional timer expiry
modifications unnecessarily.
The root cause is that WakeOvfIsDeferred fires when
!rcu_segcblist_ready_cbs() (GP not complete), but waking rcuog cannot
accelerate GP completion.
This commit therefore removes this path.
Tested with rcutorture scenarios: TREE01, TREE05, TREE08 (all NOCB
configurations) - all pass. Also stress tested using a kernel module
that floods call_rcu() to trigger the overload conditions and made the
observations confirming the findings.
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Rename the auto buffer registration functions for clarity:
- __ublk_do_auto_buf_reg() -> ublk_auto_buf_register()
- ublk_prep_auto_buf_reg_io() -> ublk_auto_buf_io_setup()
- ublk_do_auto_buf_reg() -> ublk_auto_buf_dispatch()
Add comments documenting the locking requirements for each function.
No functional change.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The root document usually has a special :ref:`genindex` link to the
generated index. This is also the case for Documentation/index.rst. The
other index.rst files deeper in the directory hierarchy usually don't.
For SPHINXDIRS builds, the root document isn't Documentation/index.rst,
but some other index.rst in the hierarchy. Currently they have a
".. only::" block to add the index link when doing SPHINXDIRS html
builds.
This is obviously very tedious and repetitive. The link is also added to
all index.rst files in the hierarchy for SPHINXDIRS builds, not just the
root document.
Put the boilerplate in a sphinx-includes/subproject-index.rst file, and
include it at the end of the root document for subproject builds in an
ad-hoc source-read extension defined in conf.py.
For now, keep having the boilerplate in translations, because this
approach currently doesn't cover translated index link headers.
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
[jc: did s/doctree/kern_doc_dir/ ]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20260123143149.2024303-1-jani.nikula@intel.com>
After renaming round_rate->determine, kerneldoc does not match anymore,
causing W=1 warnings:
pll.c:102 function parameter 'req' not described in 'zynqmp_pll_determine_rate'
pll.c:102 expecting prototype for zynqmp_pll_round_rate(). Prototype was for zynqmp_pll_determine_rate() instead
Fixes: 193650c7a8 ("clk: zynqmp: pll: convert from round_rate() to determine_rate()")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reviewed-by: Brian Masney <bmasney@redhat.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
After renaming round_rate->determine, kerneldoc does not match anymore,
causing W=1 warnings:
Warning: drivers/clk/zynqmp/divider.c:122 function parameter 'req' not described in 'zynqmp_clk_divider_determine_rate'
Warning: drivers/clk/zynqmp/divider.c:122 expecting prototype for zynqmp_clk_divider_round_rate(). Prototype was for zynqmp_clk_divider_determine_rate() instead
Fixes: 0f9cf96a01 ("clk: zynqmp: divider: convert from round_rate() to determine_rate()")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reviewed-by: Brian Masney <bmasney@redhat.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Breno Leitao says:
====================
net: convert drivers to .get_rx_ring_count (last part)
Commit 84eaf4359c ("net: ethtool: add get_rx_ring_count callback to
optimize RX ring queries") added specific support for GRXRINGS callback,
simplifying .get_rxnfc.
Remove the handling of GRXRINGS in .get_rxnfc() by moving it to the new
.get_rx_ring_count().
This simplifies the RX ring count retrieval and aligns the following
drivers with the new ethtool API for querying RX ring parameters.
* sfc
* ionic
* sfc/siena
* sfc/ef100
* fbnic
* mana
* nfp
* atlantic
* benet (this is v2 in fact, where v1 had some discussions that
required a v2). See link [0]
Link: https://lore.kernel.org/all/20260119094514.5b12a097@kernel.org/ [0]
This is covering the last drivers, and as soon as this lands, I will
change the ethtool framework to avoid calling .get_rx_ring_count for
ETHTOOL_GRXRINGS, simplifying the ethtool core framework.
====================
Link: https://patch.msgid.link/20260122-grxring_big_v4-v2-0-94dbe4dcaa10@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use the newly introduced .get_rx_ring_count ethtool ops callback instead
of handling ETHTOOL_GRXRINGS directly in .get_rxnfc().
Since ETHTOOL_GRXRINGS was the only command handled by ionic_get_rxnfc(),
remove the function entirely.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Link: https://patch.msgid.link/20260122-grxring_big_v4-v2-6-94dbe4dcaa10@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use the newly introduced .get_rx_ring_count ethtool ops callback instead
of handling ETHTOOL_GRXRINGS directly in .get_rxnfc().
Since ETHTOOL_GRXRINGS was the only command handled by mana_get_rxnfc(),
remove the function entirely.
Reviewed-by: Subbaraya Sundeep <sbhatta@marvell.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Link: https://patch.msgid.link/20260122-grxring_big_v4-v2-4-94dbe4dcaa10@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use the newly introduced .get_rx_ring_count ethtool ops callback instead
of handling ETHTOOL_GRXRINGS directly in .get_rxnfc().
Since ETHTOOL_GRXRINGS was the only command handled by be_get_rxnfc(),
remove the function entirely.
Since the be_multi_rxq() check in be_get_rxnfc() previously blocked RSS
configuration on single-queue setups (via ethtool core validation), add
an equivalent check to be_set_rxfh() to preserve this behavior, as
suggested by Jakub.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Link: https://patch.msgid.link/20260122-grxring_big_v4-v2-1-94dbe4dcaa10@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We are not deregistering the fixed phy link when hitting the early
exit condition. Add the correct early exit sequence.
Fixes: 490cb41200 ("net: bcmasp: Add support for ASP2.0 Ethernet controller")
Signed-off-by: Justin Chen <justin.chen@broadcom.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://patch.msgid.link/20260122194001.1098859-1-justin.chen@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Mauro's work to include documentation from our Python modules. His cover
letter follows:
This is an extended version of:
https://lore.kernel.org/linux-doc/cover.1768488832.git.mchehab+huawei@kernel.org/
It basically adds everything we currently have inside libs/tool/python
to "tools" book inside documentation.
This version should be independent of the other series yet to be merged,
(including the jobserver one).
The vast amount of changes here are docstring cleanups and additions.
They mainly consists on:
- ensuring that every phrase will end with a period, making it uniform
along all files;
- cleaning ups to better uniform docstrings;
- variable descriptions now use "#:" markup, as it allows autodoc to
add them inside the documentation;
- added some missing docstrings;
- some new blank lines at comments to make ReST syntax parser happy;
- add a couple of sphinx markups (mainly, code blocks).
Most of those are minor changes, affecting only comments.
It also has one patch per libarary type, adding them to docs.
For kernel-doc, I did the cleanups first, as there is one code block
inside tools/lib/python/kdoc/latex_fonts.py that would cause a Sphinx
crash without such markups.
The series actually starts with 3 fixes:
- avoid "*" markups on indexes with deep> 3 to override text
- a variable rename to stop abusing doctree name
- don't rely on cwd to get Documentation/ location
patch 4 adds support to document scripts either at:
- tools/
- scripts/
patch 5 contains a CSS to better display autodoc html output.
For those who want to play with documentation, documenting a python
file is very simple. All it takes is to use:
.. automodule:: lib.python.<dir+name>
Usually, we add a couple of control members to it to adjust
the desired documentation scope (add/remove members, showing class
inheritance, showing members that currently don't have
docstrings, etc). That's why we're using:
.. automodule:: lib.python.kdoc.enrich_formatter
:members:
:show-inheritance:
:undoc-members:
(and similar) inside tools/kdoc*.rst.
autodoc allows filtering in/out members, file docstrings, etc.
It also allows documenting just some members or functions with
directives like:
..autofunction:
..automember:
Sphinx also has a helper script to generate .rst files with
documentation:
$ sphinx-apidoc -o foobar tools/lib/python/
which can be helpful to discover what should be documented,
although changes are needed to use what it produces.
Do some changes to:
- add missing documentation strings to vars;
- add a missing docstring;
- ensure that phases will end with a period.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <3722f10361638561a5ced18cf4f409930c88270b.1768838938.git.mchehab+huawei@kernel.org>
Place parse_features module documentation at Linux Kernel docs.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <7c1e41468f765587f0962222e7f52125a039028f.1768838938.git.mchehab+huawei@kernel.org>
Place jobserver module documentation at Linux Kernel docs.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <688215d6a41d78bd5e37854472a5fc802d58c77a.1768838938.git.mchehab+huawei@kernel.org>
Ensure that kABI module documentation will describe each
debug bit.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <3b118b157e52d757bf82fd74f03b0f4bd9e8b8f1.1768838938.git.mchehab+huawei@kernel.org>
The kabi logic supports 8 debug bits, but only 6 are currently
documented. Document the remaining ones.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <60e99b9060396eac8621954d6b8a73af45df90fb.1768838938.git.mchehab+huawei@kernel.org>
Some docstring classes are not ending with a dot. Fix to make it
more uniform.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <efd0e150d8e12d8ea2665f54a96b1997f32897b7.1768838938.git.mchehab+huawei@kernel.org>
Add documentation for two consts and ensure that all sentenses
will end with a dot.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <5419ad89a5042c1571198c2f055866674808579b.1768838938.git.mchehab+huawei@kernel.org>
Add documentation for two consts and ensure that all sentenses
will end with a dot.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <c5756d7fd70697890130b41b2856c59144d01844.1768838938.git.mchehab+huawei@kernel.org>
Place kernel abi modules documentation at Linux Kernel docs.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <ddc02f11d64fdfc0d8d3e3e0967e041b5172da6c.1768838938.git.mchehab+huawei@kernel.org>
Place kernel-doc modules documentation at Linux Kernel docs.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <88ac2d82a45718c4e27aefac831586a71204ebf2.1768838938.git.mchehab+huawei@kernel.org>
In preparation to document kernel-doc module, improve its
documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <2153afaeb496e1bb8d3cc318fff26c3f99d99486.1768838938.git.mchehab+huawei@kernel.org>
In preparation to document kernel-doc module, improve its
documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <55ec8b896fe00529d326859cd094230fb5a2cd30.1768838938.git.mchehab+huawei@kernel.org>
In preparation to document kernel-doc module, improve its
documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <76ead85b4c13a8038180a792e270c3691d26cd25.1768838938.git.mchehab+huawei@kernel.org>
In preparation to document kernel-doc module, improve its
documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <14a12a43144d52345bfd405d0401d246f0885acf.1768838938.git.mchehab+huawei@kernel.org>
In preparation to document kernel-doc module, improve its
documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <ac03bf776f0929bbe822cd8269f2a31e275b8d6b.1768838938.git.mchehab+huawei@kernel.org>
In preparation to document kernel-doc module, improve its
documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <b6aabe25b45e9751885becd544a4db82dbe11ff2.1768838938.git.mchehab+huawei@kernel.org>
In preparation to document kernel-doc module, improve its
documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <65a7c6bb318e7a8cbf5c115903d507568099151a.1768838938.git.mchehab+huawei@kernel.org>
In preparation to document kernel-doc module, improve its
documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <75d58878ad6f83f24f1c0ce9e04301a000ecbaa3.1768838938.git.mchehab+huawei@kernel.org>
In preparation to document kernel-doc module, improve its
documentation.
Among the changes, it had to place the xml template inside
a code block, as otherwise doc build would break.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <6e0eb2e245eae9b4f39cf231dee32df00b9e8b7b.1768838938.git.mchehab+huawei@kernel.org>
Adding python documentation is simple with Sphinx: all we need
is to include the ext.autodoc extension and add the directories
where the Python code sits at the sys.path.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <29cbe375dc418d6fa5793f55199799b5b52dcd38.1768838938.git.mchehab+huawei@kernel.org>
Instead of relying that Sphinx will be called from Documentation/
dir, pick the location based on __file__.
Suggested-by: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <34c38718dfade91ff6f7afca5e9c1705ba253c97.1768838938.git.mchehab+huawei@kernel.org>
At Sphinx, doctree is a directory where doc build cache is stored.
Use a better name.
No functional changes.
Suggested-by: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <bab090bb4b95c735bd570c9c23c6e97851b2bf7b.1768838938.git.mchehab+huawei@kernel.org>
There's currently an issue with li marker: it is set to use
-1em, which actually makes it override the text. This is visible
on indexes that are deep enough.
Fix it.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <4f28c485b72ea27c0981cd950a1819597d6736b1.1768838938.git.mchehab+huawei@kernel.org>
When realloc() fails in add_string(), the function returns -1 but leaves
*vals pointing to the previously allocated memory. This can cause memory
leaks in callers like make_trace_array() that return on error without
freeing the partially built array.
Fix this by freeing *vals and setting it to NULL when realloc() fails.
This makes the error handling self-contained in add_string() so callers
don't need to handle cleanup on failure.
This bug is found by my static analysis tool and my code review.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: e30f8e61e2 ("tracing: Add a tracepoint verification check at build time")
Link: https://patch.msgid.link/20260119114542.1714405-1-geoffreyhe2@gmail.com
Signed-off-by: Weigang He <geoffreyhe2@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
