<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/tools/testing/selftests/net, branch v5.5-rc2</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>net/tls: Fix return values to avoid ENOTSUPP</title>
<updated>2019-12-07T04:15:39+00:00</updated>
<author>
<name>Valentin Vidic</name>
<email>vvidic@valentin-vidic.from.hr</email>
</author>
<published>2019-12-05T06:41:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4a5cdc604b9cf645e6fa24d8d9f055955c3c8516'/>
<id>4a5cdc604b9cf645e6fa24d8d9f055955c3c8516</id>
<content type='text'>
ENOTSUPP is not available in userspace, for example:

  setsockopt failed, 524, Unknown error 524

Signed-off-by: Valentin Vidic &lt;vvidic@valentin-vidic.from.hr&gt;
Acked-by: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
ENOTSUPP is not available in userspace, for example:

  setsockopt failed, 524, Unknown error 524

Signed-off-by: Valentin Vidic &lt;vvidic@valentin-vidic.from.hr&gt;
Acked-by: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: forwarding: fix race between packet receive and tc check</title>
<updated>2019-11-30T20:23:27+00:00</updated>
<author>
<name>Jiri Pirko</name>
<email>jiri@mellanox.com</email>
</author>
<published>2019-11-28T12:38:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=408469d31e9106878d2b3e428dcca9984664dfc9'/>
<id>408469d31e9106878d2b3e428dcca9984664dfc9</id>
<content type='text'>
It is possible that tc stats get checked before the packet we check for
actually arrived into the interface and accounted for.
Fix it by checking for the expected result in a loop until
timeout is reached (by default 1 second).

Fixes: 07e5c75184a1 ("selftests: forwarding: Introduce tc flower matching tests")
Signed-off-by: Jiri Pirko &lt;jiri@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
It is possible that tc stats get checked before the packet we check for
actually arrived into the interface and accounted for.
Fix it by checking for the expected result in a loop until
timeout is reached (by default 1 second).

Fixes: 07e5c75184a1 ("selftests: forwarding: Introduce tc flower matching tests")
Signed-off-by: Jiri Pirko &lt;jiri@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: pmtu: use -oneline for ip route list cache</title>
<updated>2019-11-29T20:29:55+00:00</updated>
<author>
<name>Thadeu Lima de Souza Cascardo</name>
<email>cascardo@canonical.com</email>
</author>
<published>2019-11-28T18:58:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2745aea6750ff0d2c48285d25bdb00e5b636ec8b'/>
<id>2745aea6750ff0d2c48285d25bdb00e5b636ec8b</id>
<content type='text'>
Some versions of iproute2 will output more than one line per entry, which
will cause the test to fail, like:

TEST: ipv6: list and flush cached exceptions                        [FAIL]
  can't list cached exceptions

That happens, for example, with iproute2 4.15.0. When using the -oneline
option, this will work just fine:

TEST: ipv6: list and flush cached exceptions                        [ OK ]

This also works just fine with a more recent version of iproute2, like
5.4.0.

For some reason, two lines are printed for the IPv4 test no matter what
version of iproute2 is used. Use the same -oneline parameter there instead
of counting the lines twice.

Fixes: b964641e9925 ("selftests: pmtu: Make list_flush_ipv6_exception test more demanding")
Signed-off-by: Thadeu Lima de Souza Cascardo &lt;cascardo@canonical.com&gt;
Acked-by: Stefano Brivio &lt;sbrivio@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Some versions of iproute2 will output more than one line per entry, which
will cause the test to fail, like:

TEST: ipv6: list and flush cached exceptions                        [FAIL]
  can't list cached exceptions

That happens, for example, with iproute2 4.15.0. When using the -oneline
option, this will work just fine:

TEST: ipv6: list and flush cached exceptions                        [ OK ]

This also works just fine with a more recent version of iproute2, like
5.4.0.

For some reason, two lines are printed for the IPv4 test no matter what
version of iproute2 is used. Use the same -oneline parameter there instead
of counting the lines twice.

Fixes: b964641e9925 ("selftests: pmtu: Make list_flush_ipv6_exception test more demanding")
Signed-off-by: Thadeu Lima de Souza Cascardo &lt;cascardo@canonical.com&gt;
Acked-by: Stefano Brivio &lt;sbrivio@redhat.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests/tls: add a test for fragmented messages</title>
<updated>2019-11-29T06:40:29+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>jakub.kicinski@netronome.com</email>
</author>
<published>2019-11-27T20:16:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=65190f77424d7b82c4aad7326c9cce6bd91a2fcc'/>
<id>65190f77424d7b82c4aad7326c9cce6bd91a2fcc</id>
<content type='text'>
Add a sendmsg test with very fragmented messages. This should
fill up sk_msg and test the boundary conditions.

Signed-off-by: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Reviewed-by: Simon Horman &lt;simon.horman@netronome.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add a sendmsg test with very fragmented messages. This should
fill up sk_msg and test the boundary conditions.

Signed-off-by: Jakub Kicinski &lt;jakub.kicinski@netronome.com&gt;
Reviewed-by: Simon Horman &lt;simon.horman@netronome.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next</title>
<updated>2019-11-26T04:02:57+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-11-26T04:02:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=386403a115f95997c2715691226e11a7b5cffcfd'/>
<id>386403a115f95997c2715691226e11a7b5cffcfd</id>
<content type='text'>
Pull networking updates from David Miller:
 "Another merge window, another pull full of stuff:

   1) Support alternative names for network devices, from Jiri Pirko.

   2) Introduce per-netns netdev notifiers, also from Jiri Pirko.

   3) Support MSG_PEEK in vsock/virtio, from Matias Ezequiel Vara
      Larsen.

   4) Allow compiling out the TLS TOE code, from Jakub Kicinski.

   5) Add several new tracepoints to the kTLS code, also from Jakub.

   6) Support set channels ethtool callback in ena driver, from Sameeh
      Jubran.

   7) New SCTP events SCTP_ADDR_ADDED, SCTP_ADDR_REMOVED,
      SCTP_ADDR_MADE_PRIM, and SCTP_SEND_FAILED_EVENT. From Xin Long.

   8) Add XDP support to mvneta driver, from Lorenzo Bianconi.

   9) Lots of netfilter hw offload fixes, cleanups and enhancements,
      from Pablo Neira Ayuso.

  10) PTP support for aquantia chips, from Egor Pomozov.

  11) Add UDP segmentation offload support to igb, ixgbe, and i40e. From
      Josh Hunt.

  12) Add smart nagle to tipc, from Jon Maloy.

  13) Support L2 field rewrite by TC offloads in bnxt_en, from Venkat
      Duvvuru.

  14) Add a flow mask cache to OVS, from Tonghao Zhang.

  15) Add XDP support to ice driver, from Maciej Fijalkowski.

  16) Add AF_XDP support to ice driver, from Krzysztof Kazimierczak.

  17) Support UDP GSO offload in atlantic driver, from Igor Russkikh.

  18) Support it in stmmac driver too, from Jose Abreu.

  19) Support TIPC encryption and auth, from Tuong Lien.

  20) Introduce BPF trampolines, from Alexei Starovoitov.

  21) Make page_pool API more numa friendly, from Saeed Mahameed.

  22) Introduce route hints to ipv4 and ipv6, from Paolo Abeni.

  23) Add UDP segmentation offload to cxgb4, Rahul Lakkireddy"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1857 commits)
  libbpf: Fix usage of u32 in userspace code
  mm: Implement no-MMU variant of vmalloc_user_node_flags
  slip: Fix use-after-free Read in slip_open
  net: dsa: sja1105: fix sja1105_parse_rgmii_delays()
  macvlan: schedule bc_work even if error
  enetc: add support Credit Based Shaper(CBS) for hardware offload
  net: phy: add helpers phy_(un)lock_mdio_bus
  mdio_bus: don't use managed reset-controller
  ax88179_178a: add ethtool_op_get_ts_info()
  mlxsw: spectrum_router: Fix use of uninitialized adjacency index
  mlxsw: spectrum_router: After underlay moves, demote conflicting tunnels
  bpf: Simplify __bpf_arch_text_poke poke type handling
  bpf: Introduce BPF_TRACE_x helper for the tracing tests
  bpf: Add bpf_jit_blinding_enabled for !CONFIG_BPF_JIT
  bpf, testing: Add various tail call test cases
  bpf, x86: Emit patchable direct jump as tail call
  bpf: Constant map key tracking for prog array pokes
  bpf: Add poke dependency tracking for prog array maps
  bpf: Add initial poke descriptor table for jit images
  bpf: Move owner type, jited info into array auxiliary data
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull networking updates from David Miller:
 "Another merge window, another pull full of stuff:

   1) Support alternative names for network devices, from Jiri Pirko.

   2) Introduce per-netns netdev notifiers, also from Jiri Pirko.

   3) Support MSG_PEEK in vsock/virtio, from Matias Ezequiel Vara
      Larsen.

   4) Allow compiling out the TLS TOE code, from Jakub Kicinski.

   5) Add several new tracepoints to the kTLS code, also from Jakub.

   6) Support set channels ethtool callback in ena driver, from Sameeh
      Jubran.

   7) New SCTP events SCTP_ADDR_ADDED, SCTP_ADDR_REMOVED,
      SCTP_ADDR_MADE_PRIM, and SCTP_SEND_FAILED_EVENT. From Xin Long.

   8) Add XDP support to mvneta driver, from Lorenzo Bianconi.

   9) Lots of netfilter hw offload fixes, cleanups and enhancements,
      from Pablo Neira Ayuso.

  10) PTP support for aquantia chips, from Egor Pomozov.

  11) Add UDP segmentation offload support to igb, ixgbe, and i40e. From
      Josh Hunt.

  12) Add smart nagle to tipc, from Jon Maloy.

  13) Support L2 field rewrite by TC offloads in bnxt_en, from Venkat
      Duvvuru.

  14) Add a flow mask cache to OVS, from Tonghao Zhang.

  15) Add XDP support to ice driver, from Maciej Fijalkowski.

  16) Add AF_XDP support to ice driver, from Krzysztof Kazimierczak.

  17) Support UDP GSO offload in atlantic driver, from Igor Russkikh.

  18) Support it in stmmac driver too, from Jose Abreu.

  19) Support TIPC encryption and auth, from Tuong Lien.

  20) Introduce BPF trampolines, from Alexei Starovoitov.

  21) Make page_pool API more numa friendly, from Saeed Mahameed.

  22) Introduce route hints to ipv4 and ipv6, from Paolo Abeni.

  23) Add UDP segmentation offload to cxgb4, Rahul Lakkireddy"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1857 commits)
  libbpf: Fix usage of u32 in userspace code
  mm: Implement no-MMU variant of vmalloc_user_node_flags
  slip: Fix use-after-free Read in slip_open
  net: dsa: sja1105: fix sja1105_parse_rgmii_delays()
  macvlan: schedule bc_work even if error
  enetc: add support Credit Based Shaper(CBS) for hardware offload
  net: phy: add helpers phy_(un)lock_mdio_bus
  mdio_bus: don't use managed reset-controller
  ax88179_178a: add ethtool_op_get_ts_info()
  mlxsw: spectrum_router: Fix use of uninitialized adjacency index
  mlxsw: spectrum_router: After underlay moves, demote conflicting tunnels
  bpf: Simplify __bpf_arch_text_poke poke type handling
  bpf: Introduce BPF_TRACE_x helper for the tracing tests
  bpf: Add bpf_jit_blinding_enabled for !CONFIG_BPF_JIT
  bpf, testing: Add various tail call test cases
  bpf, x86: Emit patchable direct jump as tail call
  bpf: Constant map key tracking for prog array pokes
  bpf: Add poke dependency tracking for prog array maps
  bpf: Add initial poke descriptor table for jit images
  bpf: Move owner type, jited info into array auxiliary data
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'linux-kselftest-5.5-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest</title>
<updated>2019-11-25T22:58:09+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-11-25T22:58:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=db7d275415d774de3d2151d6885bf61c33243419'/>
<id>db7d275415d774de3d2151d6885bf61c33243419</id>
<content type='text'>
Pull kselftest fixes from Shuah Khan:
 "This consists of several fixes to tests and framework.

  Masami Hiramatsu fixed several tests to build and run correctly on arm
  and other 32bit architectures"

* tag 'linux-kselftest-5.5-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests: sync: Fix cast warnings on arm
  selftests: net: Fix printf format warnings on arm
  selftests: net: Use size_t and ssize_t for counting file size
  selftests: vm: Build/Run 64bit tests only on 64bit arch
  selftests: proc: Make va_max 1MB
  kselftest: Fix NULL INSTALL_PATH for TARGETS runlist
  selftests: Move kselftest_module.sh into kselftest/
  selftests: gen_kselftest_tar.sh: Do not clobber kselftest/
  selftests: breakpoints: Fix a typo of function name
  selftests: Fix O= and KBUILD_OUTPUT handling for relative paths
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull kselftest fixes from Shuah Khan:
 "This consists of several fixes to tests and framework.

  Masami Hiramatsu fixed several tests to build and run correctly on arm
  and other 32bit architectures"

* tag 'linux-kselftest-5.5-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests: sync: Fix cast warnings on arm
  selftests: net: Fix printf format warnings on arm
  selftests: net: Use size_t and ssize_t for counting file size
  selftests: vm: Build/Run 64bit tests only on 64bit arch
  selftests: proc: Make va_max 1MB
  kselftest: Fix NULL INSTALL_PATH for TARGETS runlist
  selftests: Move kselftest_module.sh into kselftest/
  selftests: gen_kselftest_tar.sh: Do not clobber kselftest/
  selftests: breakpoints: Fix a typo of function name
  selftests: Fix O= and KBUILD_OUTPUT handling for relative paths
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: forwarding: Add speed and auto-negotiation test</title>
<updated>2019-11-19T01:11:54+00:00</updated>
<author>
<name>Amit Cohen</name>
<email>amitc@mellanox.com</email>
</author>
<published>2019-11-18T07:50:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=64916b57c0b1f5576ae5973d6ff233731b9b3751'/>
<id>64916b57c0b1f5576ae5973d6ff233731b9b3751</id>
<content type='text'>
Check configurations and packets transference with different variations
of autoneg and speed.

Test plan:
1. Test force of same speed with autoneg off
2. Test force of different speeds with autoneg off (should fail)
3. One side is autoneg on and other side sets force of common speeds
4. One side is autoneg on and other side only advertises a subset of the
   common speeds (one speed of the subset)
5. One side is autoneg on and other side only advertises a subset of the
   common speeds. Check that highest speed is negotiated
6. Test autoneg on, but each side advertises different speeds (should
   fail)

Signed-off-by: Amit Cohen &lt;amitc@mellanox.com&gt;
Signed-off-by: Ido Schimmel &lt;idosch@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Check configurations and packets transference with different variations
of autoneg and speed.

Test plan:
1. Test force of same speed with autoneg off
2. Test force of different speeds with autoneg off (should fail)
3. One side is autoneg on and other side sets force of common speeds
4. One side is autoneg on and other side only advertises a subset of the
   common speeds (one speed of the subset)
5. One side is autoneg on and other side only advertises a subset of the
   common speeds. Check that highest speed is negotiated
6. Test autoneg on, but each side advertises different speeds (should
   fail)

Signed-off-by: Amit Cohen &lt;amitc@mellanox.com&gt;
Signed-off-by: Ido Schimmel &lt;idosch@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: forwarding: lib.sh: Add wait for dev with timeout</title>
<updated>2019-11-19T01:11:54+00:00</updated>
<author>
<name>Amit Cohen</name>
<email>amitc@mellanox.com</email>
</author>
<published>2019-11-18T07:50:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8f72a9cf369090c3b94101a11cc4546f13f94925'/>
<id>8f72a9cf369090c3b94101a11cc4546f13f94925</id>
<content type='text'>
Add a function that waits for device with maximum number of iterations.
It enables to limit the waiting and prevent infinite loop.

This will be used by the subsequent patch which will set two ports to
different speeds in order to make sure they cannot negotiate a link.

Waiting for all the setup is limited with 10 minutes for each device.

Signed-off-by: Amit Cohen &lt;amitc@mellanox.com&gt;
Signed-off-by: Ido Schimmel &lt;idosch@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add a function that waits for device with maximum number of iterations.
It enables to limit the waiting and prevent infinite loop.

This will be used by the subsequent patch which will set two ports to
different speeds in order to make sure they cannot negotiate a link.

Waiting for all the setup is limited with 10 minutes for each device.

Signed-off-by: Amit Cohen &lt;amitc@mellanox.com&gt;
Signed-off-by: Ido Schimmel &lt;idosch@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: forwarding: Add ethtool_lib.sh</title>
<updated>2019-11-19T01:11:54+00:00</updated>
<author>
<name>Amit Cohen</name>
<email>amitc@mellanox.com</email>
</author>
<published>2019-11-18T07:50:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=646cf7ed9abba7cc1a45f70243cd94808d4c8b6b'/>
<id>646cf7ed9abba7cc1a45f70243cd94808d4c8b6b</id>
<content type='text'>
Functions:
1. speeds_arr_get
	The function returns an array of speed values from
        /usr/include/linux/ethtool.h The array looks as follows:
	[10baseT/Half] = 0,
	[10baseT/Full] = 1,
	...

2. ethtool_set:
	params: cmd
	The function runs ethtool by cmd (ethtool -s cmd) and checks if
	there was an error in configuration

3. dev_speeds_get:
	params: dev, with_mode (0 or 1), adver (0 or 1)
	return value: Array of supported/Advertised link modes
	with/without mode

	* Example 1:
	speeds_get swp1 0 0
	return: 1000 10000 40000
	* Example 2:
	speeds_get swp1 1 1
	return: 1000baseKX/Full 10000baseKR/Full 40000baseCR4/Full

4. common_speeds_get:
	params: dev1, dev2, with_mode (0 or 1), adver (0 or 1)
	return value: Array of common speeds of dev1 and dev2

	* Example:
	common_speeds_get swp1 swp2 0 0
	return: 1000 10000
	Assuming that swp1 supports 1000 10000 40000 and swp2 supports
	1000 10000

Signed-off-by: Amit Cohen &lt;amitc@mellanox.com&gt;
Signed-off-by: Ido Schimmel &lt;idosch@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Functions:
1. speeds_arr_get
	The function returns an array of speed values from
        /usr/include/linux/ethtool.h The array looks as follows:
	[10baseT/Half] = 0,
	[10baseT/Full] = 1,
	...

2. ethtool_set:
	params: cmd
	The function runs ethtool by cmd (ethtool -s cmd) and checks if
	there was an error in configuration

3. dev_speeds_get:
	params: dev, with_mode (0 or 1), adver (0 or 1)
	return value: Array of supported/Advertised link modes
	with/without mode

	* Example 1:
	speeds_get swp1 0 0
	return: 1000 10000 40000
	* Example 2:
	speeds_get swp1 1 1
	return: 1000baseKX/Full 10000baseKR/Full 40000baseCR4/Full

4. common_speeds_get:
	params: dev1, dev2, with_mode (0 or 1), adver (0 or 1)
	return value: Array of common speeds of dev1 and dev2

	* Example:
	common_speeds_get swp1 swp2 0 0
	return: 1000 10000
	Assuming that swp1 supports 1000 10000 40000 and swp2 supports
	1000 10000

Signed-off-by: Amit Cohen &lt;amitc@mellanox.com&gt;
Signed-off-by: Ido Schimmel &lt;idosch@mellanox.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: net: avoid ptl lock contention in tcp_mmap</title>
<updated>2019-11-16T21:12:46+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2019-11-16T01:55:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=597b01edafac57aafdbf1ca51e26ceb41c371912'/>
<id>597b01edafac57aafdbf1ca51e26ceb41c371912</id>
<content type='text'>
tcp_mmap is used as a reference program for TCP rx zerocopy,
so it is important to point out some potential issues.

If multiple threads are concurrently using getsockopt(...
TCP_ZEROCOPY_RECEIVE), there is a chance the low-level mm
functions compete on shared ptl lock, if vma are arbitrary placed.

Instead of letting the mm layer place the chunks back to back,
this patch enforces an alignment so that each thread uses
a different ptl lock.

Performance measured on a 100 Gbit NIC, with 8 tcp_mmap clients
launched at the same time :

$ for f in {1..8}; do ./tcp_mmap -H 2002:a05:6608:290:: &amp; done

In the following run, we reproduce the old behavior by requesting no alignment :

$ tcp_mmap -sz -C $((128*1024)) -a 4096
received 32768 MB (100 % mmap'ed) in 9.69532 s, 28.3516 Gbit
  cpu usage user:0.08634 sys:3.86258, 120.511 usec per MB, 171839 c-switches
received 32768 MB (100 % mmap'ed) in 25.4719 s, 10.7914 Gbit
  cpu usage user:0.055268 sys:21.5633, 659.745 usec per MB, 9065 c-switches
received 32768 MB (100 % mmap'ed) in 28.5419 s, 9.63069 Gbit
  cpu usage user:0.057401 sys:23.8761, 730.392 usec per MB, 14987 c-switches
received 32768 MB (100 % mmap'ed) in 28.655 s, 9.59268 Gbit
  cpu usage user:0.059689 sys:23.8087, 728.406 usec per MB, 18509 c-switches
received 32768 MB (100 % mmap'ed) in 28.7808 s, 9.55074 Gbit
  cpu usage user:0.066042 sys:23.4632, 718.056 usec per MB, 24702 c-switches
received 32768 MB (100 % mmap'ed) in 28.8259 s, 9.5358 Gbit
  cpu usage user:0.056547 sys:23.6628, 723.858 usec per MB, 23518 c-switches
received 32768 MB (100 % mmap'ed) in 28.8808 s, 9.51767 Gbit
  cpu usage user:0.059357 sys:23.8515, 729.703 usec per MB, 14691 c-switches
received 32768 MB (100 % mmap'ed) in 28.8879 s, 9.51534 Gbit
  cpu usage user:0.047115 sys:23.7349, 725.769 usec per MB, 21773 c-switches

New behavior (automatic alignment based on Hugepagesize),
we can see the system overhead being dramatically reduced.

$ tcp_mmap -sz -C $((128*1024))
received 32768 MB (100 % mmap'ed) in 13.5339 s, 20.3103 Gbit
  cpu usage user:0.122644 sys:3.4125, 107.884 usec per MB, 168567 c-switches
received 32768 MB (100 % mmap'ed) in 16.0335 s, 17.1439 Gbit
  cpu usage user:0.132428 sys:3.55752, 112.608 usec per MB, 188557 c-switches
received 32768 MB (100 % mmap'ed) in 17.5506 s, 15.6621 Gbit
  cpu usage user:0.155405 sys:3.24889, 103.891 usec per MB, 226652 c-switches
received 32768 MB (100 % mmap'ed) in 19.1924 s, 14.3222 Gbit
  cpu usage user:0.135352 sys:3.35583, 106.542 usec per MB, 207404 c-switches
received 32768 MB (100 % mmap'ed) in 22.3649 s, 12.2906 Gbit
  cpu usage user:0.142429 sys:3.53187, 112.131 usec per MB, 250225 c-switches
received 32768 MB (100 % mmap'ed) in 22.5336 s, 12.1986 Gbit
  cpu usage user:0.140654 sys:3.61971, 114.757 usec per MB, 253754 c-switches
received 32768 MB (100 % mmap'ed) in 22.5483 s, 12.1906 Gbit
  cpu usage user:0.134035 sys:3.55952, 112.718 usec per MB, 252997 c-switches
received 32768 MB (100 % mmap'ed) in 22.6442 s, 12.139 Gbit
  cpu usage user:0.126173 sys:3.71251, 117.147 usec per MB, 253728 c-switches

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Soheil Hassas Yeganeh &lt;soheil@google.com&gt;
Cc: Arjun Roy &lt;arjunroy@google.com&gt;
Acked-by: Soheil Hassas Yeganeh &lt;soheil@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
tcp_mmap is used as a reference program for TCP rx zerocopy,
so it is important to point out some potential issues.

If multiple threads are concurrently using getsockopt(...
TCP_ZEROCOPY_RECEIVE), there is a chance the low-level mm
functions compete on shared ptl lock, if vma are arbitrary placed.

Instead of letting the mm layer place the chunks back to back,
this patch enforces an alignment so that each thread uses
a different ptl lock.

Performance measured on a 100 Gbit NIC, with 8 tcp_mmap clients
launched at the same time :

$ for f in {1..8}; do ./tcp_mmap -H 2002:a05:6608:290:: &amp; done

In the following run, we reproduce the old behavior by requesting no alignment :

$ tcp_mmap -sz -C $((128*1024)) -a 4096
received 32768 MB (100 % mmap'ed) in 9.69532 s, 28.3516 Gbit
  cpu usage user:0.08634 sys:3.86258, 120.511 usec per MB, 171839 c-switches
received 32768 MB (100 % mmap'ed) in 25.4719 s, 10.7914 Gbit
  cpu usage user:0.055268 sys:21.5633, 659.745 usec per MB, 9065 c-switches
received 32768 MB (100 % mmap'ed) in 28.5419 s, 9.63069 Gbit
  cpu usage user:0.057401 sys:23.8761, 730.392 usec per MB, 14987 c-switches
received 32768 MB (100 % mmap'ed) in 28.655 s, 9.59268 Gbit
  cpu usage user:0.059689 sys:23.8087, 728.406 usec per MB, 18509 c-switches
received 32768 MB (100 % mmap'ed) in 28.7808 s, 9.55074 Gbit
  cpu usage user:0.066042 sys:23.4632, 718.056 usec per MB, 24702 c-switches
received 32768 MB (100 % mmap'ed) in 28.8259 s, 9.5358 Gbit
  cpu usage user:0.056547 sys:23.6628, 723.858 usec per MB, 23518 c-switches
received 32768 MB (100 % mmap'ed) in 28.8808 s, 9.51767 Gbit
  cpu usage user:0.059357 sys:23.8515, 729.703 usec per MB, 14691 c-switches
received 32768 MB (100 % mmap'ed) in 28.8879 s, 9.51534 Gbit
  cpu usage user:0.047115 sys:23.7349, 725.769 usec per MB, 21773 c-switches

New behavior (automatic alignment based on Hugepagesize),
we can see the system overhead being dramatically reduced.

$ tcp_mmap -sz -C $((128*1024))
received 32768 MB (100 % mmap'ed) in 13.5339 s, 20.3103 Gbit
  cpu usage user:0.122644 sys:3.4125, 107.884 usec per MB, 168567 c-switches
received 32768 MB (100 % mmap'ed) in 16.0335 s, 17.1439 Gbit
  cpu usage user:0.132428 sys:3.55752, 112.608 usec per MB, 188557 c-switches
received 32768 MB (100 % mmap'ed) in 17.5506 s, 15.6621 Gbit
  cpu usage user:0.155405 sys:3.24889, 103.891 usec per MB, 226652 c-switches
received 32768 MB (100 % mmap'ed) in 19.1924 s, 14.3222 Gbit
  cpu usage user:0.135352 sys:3.35583, 106.542 usec per MB, 207404 c-switches
received 32768 MB (100 % mmap'ed) in 22.3649 s, 12.2906 Gbit
  cpu usage user:0.142429 sys:3.53187, 112.131 usec per MB, 250225 c-switches
received 32768 MB (100 % mmap'ed) in 22.5336 s, 12.1986 Gbit
  cpu usage user:0.140654 sys:3.61971, 114.757 usec per MB, 253754 c-switches
received 32768 MB (100 % mmap'ed) in 22.5483 s, 12.1906 Gbit
  cpu usage user:0.134035 sys:3.55952, 112.718 usec per MB, 252997 c-switches
received 32768 MB (100 % mmap'ed) in 22.6442 s, 12.139 Gbit
  cpu usage user:0.126173 sys:3.71251, 117.147 usec per MB, 253728 c-switches

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Soheil Hassas Yeganeh &lt;soheil@google.com&gt;
Cc: Arjun Roy &lt;arjunroy@google.com&gt;
Acked-by: Soheil Hassas Yeganeh &lt;soheil@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
</feed>
