This commit allows setting the RSS hash generation parameters from
ethtool. When setting parameters for a given flow type from ethtool
(e.g. tcp4), all the corresponding flows in the flow table are updated,
according to the supported hash parameters.
For example, when configuring TCP over IPv4 hash parameters to be
src/dst IP + src/dst port ("ethtool -N eth0 rx-flow-hash tcp4 sdfn"),
we only set the "src/dst port" hash parameters on the non-fragmented TCP
over IPv4 flows.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
One of the classification action that can be performed is to compute a
hash of the packet header based on some header fields, and lookup a RSS
table based on this hash to determine the final RxQ.
This is done by adding one lookup entry per flow per port, so that we
can configure the hash generation parameters for each flow and each
port.
There are 2 possible engines that can be used for RSS hash generation :
- C3HA, that generates a hash based on up to 4 header-extracted fields
- C3HB, that does the same as c3HA, but also includes L4 info in the hash
There are a lot of fields that can be extracted from the header. For now,
we only use the ones that we can configure using ethtool :
- DST MAC address
- L3 info
- Source IP
- Destination IP
- Source port
- Destination port
The C3HB engine is selected when we use L4 fields (src/dst port).
Header parser Dec table
Ingress pkt +-------------+ flow id +----------------------------+
------------->| TCAM + SRAM |-------->|TCP IPv4 w/ VLAN, not frag |
+-------------+ |TCP IPv4 w/o VLAN, not frag |
|TCP IPv4 w/ VLAN, frag |--+
|etc. | |
+----------------------------+ |
|
Flow table |
+---------+ +------------+ +--------------------------+ |
| RSS tbl |<--| Classifier |<--------| flow 0: C2 lookup | |
+---------+ +------------+ | C3 lookup port 0 | |
| | | C3 lookup port 1 | |
+-----------+ +-------------+ | ... | |
| C2 engine | | C3H engines | | flow 1: C2 lookup |<--+
+-----------+ +-------------+ | C3 lookup port 0 |
| ... |
| ... |
| flow 51 : C2 lookup |
| ... |
+--------------------------+
The C2 engine also gains the role of enabling and disabling the RSS
table lookup for this packet.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PPv2 classifier allows to perform classification operations on each
ingress packet, based on the flow the packet is assigned to.
The current code uses only 1 flow per port, and the only classification
action consists of assigning the rx queue to the packet, depending on the
port.
In preparation for adding RSS support, we have to split all incoming
traffic into different flows. Since RSS assigns a rx queue depending on
the hash of some header fields, we have to make sure that the hash is
generated in a consistent way for all packets in the same flow.
What we call a "flow" is actually a set of attributes attached to a
packet that depends on various L2/L3/L4 info.
This patch introduces 52 flows, wich are a combination of various L2, L3
and L4 attributes :
- Whether or not the packet has a VLAN tag
- Whether the packet is IPv4, IPv6 or something else
- Whether the packet is TCP, UDP or something else
- Whether or not the packet is fragmented at L3 level.
The flow is associated to a packet by the Header Parser. Each flow
corresponds to an entry in the decoding table. This entry then points to
the sequence of classification lookups to be performed by the
classifier, represented in the flow table.
For now, the only lookup we perform is a C2 lookup to set the default
rx queue.
Header parser Dec table
Ingress pkt +-------------+ flow id +----------------------------+
------------->| TCAM + SRAM |-------->|TCP IPv4 w/ VLAN, not frag |
+-------------+ |TCP IPv4 w/o VLAN, not frag |
|TCP IPv4 w/ VLAN, frag |--+
|etc. | |
+----------------------------+ |
|
Flow table |
+------------+ +---------------------+ |
To RxQ <---| Classifier |<-------| flow 0: C2 lookup |<--------+
+------------+ | flow 1: C2 lookup |
| | ... |
+------------+ | flow 51 : C2 lookup |
| C2 engine | +---------------------+
+------------+
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PPv2 Controller has a classifier, that can perform multiple lookup
operations for each packet, using different engines.
One of these engines is the C2 engine, which performs TCAM based lookups
on data extracted from the packet header. When a packet matches an
entry, the engine sets various attributes, used to perform
classification operations.
One of these attributes is the rx queue in which the packet should be sent.
The current code uses the lookup_id table (also called decoding table)
to assign the rx queue. However, this only works if we use one entry per
port in the decoding table, which won't be the case once we add RSS
lookups.
This patch uses the C2 engine to assign the rx queue to each packet.
The C2 engine is used through the flow table, which dictates what
classification operations are done for a given flow.
Right now, we have one flow per port, which contains every ingress
packet for this port.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
mvpp22_init_rss function configures the RSS parameters for each port, so
rename it accordingly. Since this function relies on classifier
configuration, move its call right after the classifier config.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When filling the RSS table, we have to make sure that the rx queue is
attached to an online CPU.
This patch is not a full support for cpu_hotplug, but rather a way to
make sure that we don't break network on system booted with the maxcpus
parameter.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds an extra indirection when setting the indirection table
into the RSS hardware table to improve the packets distribution across
CPUs. For example, if 2 queues are used on a multi-core system this new
indirection will choose two queues on two different CPUs instead of the
two first queues which are on the same first CPU.
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the RSS indirection table support, allowing to use the
ethtool -x and -X options to dump and set this table.
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
[Maxime: Small warning fixes, use one table per port]
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
PPv2 Controller has 8 RSS Tables, of 32 entries each. A lookup in the
RXQ2RSS_TABLE is performed for each incoming packet, and the RSS Table
to be used is chosen according to the default rx queue that would be
used for the packet.
This default rx queue is set in the Lookup_id Table (also called
Decoding Table), and is equal to the port->first_rxq.
Since the Classifier itself isn't active at any time for the moment,
this doesn't have a direct effect, the default rx queue at the moment is
the one where all packets end-up into.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no RSS_TABLE register in PPv2 Controller. The register 0x1510
which was specified is actually named "RSS_HASH_SEL", but isn't used by
this driver at all.
Based on how this register was used, it should have been the
RXQ2RSS_TABLE register, which allows to select the RSS table that will
be used for the incoming packet.
The RSS_TABLE_POINTER is actually a field of this RXQ2RSS_TABLE
register.
Since RSS tables are actually not used by the driver for now, this
commit does not fix a runtime bug.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cosmetic patch fixing a typo in one of the RSS comments.
Signed-off-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The number of receive queue per port is :
- MVPP2_DEFAULT_RXQ if in single queue mode
- MVPP2_DEFAULT_RXQ * num_possible_cpus if in multi queue mode
with MVPP2_DEFAULT_RXQ = 4.
However, we don't use the extra rx queues at the moment, we really only
need one per port per CPU, until some more advanced classification rules
are implemented.
Suggested-by: Stefan Chulski <stefanc@marvell.com>
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There's a dedicated #define that indicates the number of rx queues per
port per cpu, this commit removes a harcoded use of that value
This doesn't fix any runtime bugs since the harcoded value matches the
expected value.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since RSS only applies when we have per-cpu rx queues, it should only
be enabled when the driver is configured to make use of multi-queue
mode.
Signed-off-by: Yan Markman <ymarkman@marvell.com>
[Maxime: Commit message]
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The multi queue mode is needed to have RSS available, and offers some
nice advantages, being able to have one rx queue vector per CPU.
This mode has been usable through the use of a module parameter, this
commit makes it the default value.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PPv2 driver defines 2 "queue_modes" :
- QDIST_SINGLE_MODE, where each port share one rx queue vector
between all CPUs
- QDIST_MULTI_MODE, where each port has one rx queue vector per CPU.
Multi queue mode isn't available on PPv2.1, make sure we fallback to
single mode when running on this revision.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The size of the the RSS indirection tables should be defined in mvpp2.h,
so that we can use it in all files of the PPv2 driver.
This commit moves the define in mvpp2.h, and adds the missing #include
in mvpp2_cls.h.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Include guards should be put before #includes. This doesn't fix any bug,
but prevent future compilation issues when adding new files in the mvpp2
driver
The Header Parser init function needs the platform_device definition,
and with the fixed include guards we need to add the missing include.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The udpgso benchmark compares various configurations of UDP and TCP.
Including one that is not upstream, udp zerocopy. This is a leftover
from the earlier RFC patchset.
The test is part of kselftests and run in continuous spinners. Remove
the failing case to make the test start passing.
Fixes: 3a687bef14 ("selftests: udp gso benchmark")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently ftrace displays data in trace output like so:
_-----=> irqs-off
/ _----=> need-resched
| / _---=> hardirq/softirq
|| / _--=> preempt-depth
||| / delay
TASK-PID CPU TGID |||| TIMESTAMP FUNCTION
| | | | |||| | |
bash-1091 [000] ( 1091) d..2 28.313544: sched_switch:
However Android's trace visualization tools expect a slightly different
format due to an out-of-tree patch patch that was been carried for a
decade, notice that the TGID and CPU fields are reversed:
_-----=> irqs-off
/ _----=> need-resched
| / _---=> hardirq/softirq
|| / _--=> preempt-depth
||| / delay
TASK-PID TGID CPU |||| TIMESTAMP FUNCTION
| | | | |||| | |
bash-1091 ( 1091) [002] d..2 64.965177: sched_switch:
From kernel v4.13 onwards, during which TGID was introduced, tracing
with systrace on all Android kernels will break (most Android kernels
have been on 4.9 with Android patches, so this issues hasn't been seen
yet). From v4.13 onwards things will break.
The chrome browser's tracing tools also embed the systrace viewer which
uses the legacy TGID format and updates to that are known to be
difficult to make.
Considering this, I suggest we make this change to the upstream kernel
and backport it to all Android kernels. I believe this feature is merged
recently enough into the upstream kernel that it shouldn't be a problem.
Also logically, IMO it makes more sense to group the TGID with the
TASK-PID and the CPU after these.
Link: http://lkml.kernel.org/r/20180626000822.113931-1-joel@joelfernandes.org
Cc: jreck@google.com
Cc: tkjos@google.com
Cc: stable@vger.kernel.org
Fixes: 441dae8f2f ("tracing: Add support for display of tgid in trace output")
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If variable length link layer headers result in a packet shorter
than dev->hard_header_len, reset the network header offset. Else
skb->mac_len may exceed skb->len after skb_mac_reset_len.
packet_sendmsg_spkt already has similar logic.
Fixes: b84bbaf7a6 ("packet: in packet_snd start writing at link layer allocation")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When pulling the NSH header in nsh_gso_segment, set the mac length
based on the encapsulated packet type.
skb_reset_mac_len computes an offset to the network header, which
here still points to the outer packet:
> skb_reset_network_header(skb);
> [...]
> __skb_pull(skb, nsh_len);
> skb_reset_mac_header(skb); // now mac hdr starts nsh_len == 8B after net hdr
> skb_reset_mac_len(skb); // mac len = net hdr - mac hdr == (u16) -8 == 65528
> [..]
> skb_mac_gso_segment(skb, ..)
Link: http://lkml.kernel.org/r/CAF=yD-KeAcTSOn4AxirAxL8m7QAS8GBBe1w09eziYwvPbbUeYA@mail.gmail.com
Reported-by: syzbot+7b9ed9872dab8c32305d@syzkaller.appspotmail.com
Fixes: c411ed8545 ("nsh: add GSO support")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Julian Wiedmann says:
====================
s390/qeth: updates 2018-07-11
please apply this first batch of qeth patches for net-next. It brings the
usual cleanups, and some performance improvements to the transmit paths.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the xmit of offload-eligible (ie IPv4) traffic on OSA over to the
new, copy-free path.
As with L2, we'll need to preserve the skb_orphan() behaviour of the
old code path until TX completion is sufficiently fast.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This implements a new xmit path for L3 HiperSockets, which carves the
HW header from skb headroom instead of allocating it from the hdr cache.
It also adds NETIF_F_SG support.
The delta in qeth_l3_xmit() is all just removal of IQD-specific code and
some minor consolidation.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for future work, move the high-level xmit work into a
separate wrapper. This matches the L2 xmit code.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a L3 device doesn't offer TSO, allow the stack to build full-size
GSO skbs.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove some redundant EXPORTs. While at it, also move some L2-only
prototypes into the proper header file.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reshuffle the code a bit so that everything is in one place.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Consolidate duplicated code, fix the misuse of RTN_UNSPEC and simplify
the handling of non-unicast traffic on IQD devices.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Changing a device's address lists (or its promisc mode) already triggers
an RX modeset, there's no need to do it manually from the L2 driver's
ndo_vlan_rx_kill_vid() hook.
Also when setting a device online, dev_open() already calls
dev_set_rx_mode(). So a manual modeset is only necessary from the
recovery path.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Except for tracing, the pointer is not used.
At the same time, accessing it from qeth_qdio_output_handler() is racy:
whenever qeth_qdio_cq_handler() gets control, its call to
qeth_qdio_handle_aob() frees the AOB.
So the AOB pointer that qeth_qdio_output_handler() stores into 'buffer'
can go stale at any time, and trigger a use-after-free.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the new qeth_scrub_qdio_buffer() helper, remove an extra parameter
from qeth_clear_output_buffer(), init the bufstates.user field just once
(in qeth_flush_buffers()) and remove some noisy trace messages.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In commit 5fa12739a5 ("net: ipv4: listify ip_rcv_finish") calling
dst_input(skb) was split-out. The ip_sublist_rcv_finish() just calls
dst_input(skb) in a loop.
The problem is that ip_sublist_rcv_finish() forgot to remove the SKB
from the list before invoking dst_input(). Further more we need to
clear skb->next as other parts of the network stack use another kind
of SKB lists for xmit_more (see dev_hard_start_xmit).
A crash occurs if e.g. dst_input() invoke ip_forward(), which calls
dst_output()/ip_output() that eventually calls __dev_queue_xmit() +
sch_direct_xmit(), and a crash occurs in validate_xmit_skb_list().
This patch only fixes the crash, but there is a huge potential for
a performance boost if we can pass an SKB-list through to ip_forward.
Fixes: 5fa12739a5 ("net: ipv4: listify ip_rcv_finish")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With commit 044e6e3d74: "ext4: don't update checksum of new
initialized bitmaps" the buffer valid bit will get set without
actually setting up the checksum for the allocation bitmap, since the
checksum will get calculated once we actually allocate an inode or
block.
If we are doing this, then we need to (re-)check the verified bit
after we take the block group lock. Otherwise, we could race with
another process reading and verifying the bitmap, which would then
complain about the checksum being invalid.
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1780137
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
The rcutorture test module currently increments both successes and error
for the barrier test upon error, which results in misleading statistics
being printed. This commit therefore changes the code to increment the
success counter only when the test actually passes.
This change was tested by by returning from the barrier callback without
incrementing the callback counter, thus introducing what appeared to
rcutorture to be rcu_barrier() failures.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
When rcutorture is built in to the kernel, an earlier patch detects
that and raises the priority of RCU's kthreads to allow rcutorture's
RCU priority boosting tests to succeed.
However, if rcutorture is built as a module, those priorities must be
raised manually via the rcutree.kthread_prio kernel boot parameter.
If this manual step is not taken, rcutorture's RCU priority boosting
tests will fail due to kthread starvation. One approach would be to
raise the default priority, but that risks breaking existing users.
Another approach would be to allow runtime adjustment of RCU's kthread
priorities, but that introduces numerous "interesting" race conditions.
This patch therefore instead detects too-low priorities, and prints a
message and disables the RCU priority boosting tests in that case.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The get_seconds() call is deprecated because it overflows on 32-bit
architectures. The algorithm in rcu_torture_stall() can deal with
the overflow, but another problem here is that using a CLOCK_REALTIME
stamp can lead to a false-positive stall warning when a settimeofday()
happens concurrently.
Using ktime_get_seconds() instead avoids those issues and will never
overflow. The added cast to 'unsigned long' however is necessary to
make ULONG_CMP_LT() work correctly.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Currently, with RCU_BOOST disabled, I get no failures when forcing
rcutorture to test RCU boost priority inversion. The reason seems to be
that we don't check for failures if the callback never ran at all for
the duration of the boost-test loop.
Further, the 'rtb' and 'rtbf' counters seem to be used inconsistently.
'rtb' is incremented at the start of each test and 'rtbf' is incremented
per-cpu on each failure of call_rcu. So its possible 'rtbf' > 'rtb'.
To test the boost with rcutorture, I did following on a 4-CPU x86 machine:
modprobe rcutorture test_boost=2
sleep 20
rmmod rcutorture
With patch:
rtbf: 8 rtb: 12
Without patch:
rtbf: 0 rtb: 2
In summary this patch:
- Increments failed and total test counters once per boost-test.
- Checks for failure cases correctly.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Currently rcutorture is not able to torture RCU boosting properly. This
is because the rcutorture's boost threads which are doing the torturing
may be throttled due to RT throttling.
This patch makes rcutorture use the right torture technique (unthrottled
rcutorture boost tasks) for torturing RCU so that the test fails
correctly when no boost is available.
Currently this requires accessing sysctl_sched_rt_runtime directly, but
that should be Ok since rcutorture is test code. Such direct access is
also only possible if rcutorture is used as a built-in so make it
conditional on that.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
For RCU implementations supporting multiple types of reader protection,
rcutorture currently randomly selects the combinations of types of
protection for each phase of each reader. The problem with this,
for example, given the four kinds of protection for RCU-sched
(local_irq_disable(), local_bh_disable(), preempt_disable(), and
rcu_read_lock_sched()), the reader will be protected by a single
mechanism only 25% of the time. We really heavier testing of single
read-side mechanisms.
This commit therefore uses only a single mechanism about 60% of the time,
half of the time explicitly and one-eighth of the time by chance.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit enables rcutorture to test whether RCU properly aggregates
different types of read-side critical sections into a larger section
covering the set. It does this by extending an initial read-side
critical section randomly for a random number of extensions. There is
a new rcu_torture_ops field ->extendable that specifies what extensions
are permitted for a given flavor of RCU (for example, SRCU does not
permit any extensions, while RCU-sched permits all types). Note that
if a given operation (for example, local_bh_disable()) extends an RCU
read-side critical section, then rcutorture feels free to also start
and end the critical section with that operation's type of disabling.
Disabling operations include local_bh_disable(), local_irq_disable(),
and preempt_disable(). This commit also adds a new "busted_srcud"
torture type, which verifies rcutorture's ability to detect extensions
of RCU read-side critical sections that are not handled. Gotta test
the test, after all!
Note that it is not legal to invoke local_bh_disable() with interrupts
disabled, and this transition is avoided by overriding the random-number
generator when it wants to call local_bh_disable() while interrupts
are disabled. The code instead leaves both interrupts and bh/softirq
disabled in this case.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit saves a few lines of code by making rcu_torture_timer()
invoke rcu_torture_one_read(), thus completing the consolidation of
code between rcu_torture_timer() and rcu_torture_reader().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Currently, the rcu_torture_timer() function uses a single global
torture_random_state structure protected by a single global lock.
This conflicts to some extent with performance and scalability,
but even more with the goal of consolidating read-side testing
with rcu_torture_reader(). This commit therefore creates a per-CPU
torture_random_state structure for use by rcu_torture_timer() and
eliminates the lock.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Make rcu_torture_timer_rand static, per 0day Test Robot report. ]
Currently, rcu_torture_timer() relies on a lock to guard updates to
n_rcu_torture_timers. Unfortunately, consolidating code with
rcu_torture_reader() will dispense with this lock. This commit
therefore makes n_rcu_torture_timers be an atomic_long_t and uses
atomic_long_inc() to carry out the update.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit extracts the code executed on each pass through the loop
in rcu_torture_reader() into a new rcu_torture_one_read() function.
This new function will also be used by rcu_torture_timer().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Back when RCU had a debugfs interface, there was a test version and
sequence number that allowed associating debugfs data with a particular
test run, where the test run started with modprobe and ended with rmmod,
which was how tests were run back on the old ABAT system within IBM.
But rcutorture testing no longer runs on ABAT, and there is no longer an
RCU debugfs interface, so there is no longer any need for test versions
and sequence numbers.
This commit therefore removes the rcutorture_record_test_transition()
and rcutorture_record_progress() functions, and along with them the
rcutorture_testseq and rcutorture_vernum variables that they update.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
