| 0e0a7e37 | 22-Apr-2025 |
Joshua Washington <joshwash@google.com> |
xdp: create locked/unlocked instances of xdp redirect target setters
Commit 03df156dd3a6 ("xdp: double protect netdev->xdp_flags with
netdev->lock") introduces the netdev lock to xdp_set_features_fl
xdp: create locked/unlocked instances of xdp redirect target setters
Commit 03df156dd3a6 ("xdp: double protect netdev->xdp_flags with
netdev->lock") introduces the netdev lock to xdp_set_features_flag().
The change includes a _locked version of the method, as it is possible
for a driver to have already acquired the netdev lock before calling
this helper. However, the same applies to
xdp_features_(set|clear)_redirect_flags(), which ends up calling the
unlocked version of xdp_set_features_flags() leading to deadlocks in
GVE, which grabs the netdev lock as part of its suspend, reset, and
shutdown processes:
[ 833.265543] WARNING: possible recursive locking detected
[ 833.270949] 6.15.0-rc1 #6 Tainted: G E
[ 833.276271] --------------------------------------------
[ 833.281681] systemd-shutdow/1 is trying to acquire lock:
[ 833.287090] ffff949d2b148c68 (&dev->lock){+.+.}-{4:4}, at: xdp_set_features_flag+0x29/0x90
[ 833.295470]
[ 833.295470] but task is already holding lock:
[ 833.301400] ffff949d2b148c68 (&dev->lock){+.+.}-{4:4}, at: gve_shutdown+0x44/0x90 [gve]
[ 833.309508]
[ 833.309508] other info that might help us debug this:
[ 833.316130] Possible unsafe locking scenario:
[ 833.316130]
[ 833.322142] CPU0
[ 833.324681] ----
[ 833.327220] lock(&dev->lock);
[ 833.330455] lock(&dev->lock);
[ 833.333689]
[ 833.333689] *** DEADLOCK ***
[ 833.333689]
[ 833.339701] May be due to missing lock nesting notation
[ 833.339701]
[ 833.346582] 5 locks held by systemd-shutdow/1:
[ 833.351205] #0: ffffffffa9c89130 (system_transition_mutex){+.+.}-{4:4}, at: __se_sys_reboot+0xe6/0x210
[ 833.360695] #1: ffff93b399e5c1b8 (&dev->mutex){....}-{4:4}, at: device_shutdown+0xb4/0x1f0
[ 833.369144] #2: ffff949d19a471b8 (&dev->mutex){....}-{4:4}, at: device_shutdown+0xc2/0x1f0
[ 833.377603] #3: ffffffffa9eca050 (rtnl_mutex){+.+.}-{4:4}, at: gve_shutdown+0x33/0x90 [gve]
[ 833.386138] #4: ffff949d2b148c68 (&dev->lock){+.+.}-{4:4}, at: gve_shutdown+0x44/0x90 [gve]
Introduce xdp_features_(set|clear)_redirect_target_locked() versions
which assume that the netdev lock has already been acquired before
setting the XDP feature flag and update GVE to use the locked version.
Fixes: 03df156dd3a6 ("xdp: double protect netdev->xdp_flags with netdev->lock")
Tested-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Harshitha Ramamurthy <hramamurthy@google.com>
Signed-off-by: Joshua Washington <joshwash@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20250422011643.3509287-1-joshwash@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
show more ...
|
| 293b4936 | 21-Mar-2025 |
Joshua Washington <joshwash@google.com> |
gve: add XDP DROP and PASS support for DQ
This patch adds support for running XDP programs on DQ, along with
rudimentary processing for XDP_DROP and XDP_PASS. These actions require
very limited driv
gve: add XDP DROP and PASS support for DQ
This patch adds support for running XDP programs on DQ, along with
rudimentary processing for XDP_DROP and XDP_PASS. These actions require
very limited driver functionality when it comes to processing an XDP
buffer, so currently if the XDP action is not XDP_PASS, the packet is
dropped and stats are updated.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Praveen Kaliginedi <pkaligineedi@google.com>
Signed-off-by: Joshua Washington <joshwash@google.com>
Signed-off-by: Harshitha Ramamurthy<hramamurthy@google.com>
Link: https://patch.msgid.link/20250321002910.1343422-7-hramamurthy@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
show more ...
|
| 346fb86d | 21-Mar-2025 |
Joshua Washington <joshwash@google.com> |
gve: update XDP allocation path support RX buffer posting
In order to support installing an XDP program on DQ, RX buffers need to
be reposted using 4K buffers, which is larger than the default packe
gve: update XDP allocation path support RX buffer posting
In order to support installing an XDP program on DQ, RX buffers need to
be reposted using 4K buffers, which is larger than the default packet
buffer size of 2K. This is needed to accommodate the extra head and tail
that accompanies the data portion of an XDP buffer. Continuing to use 2K
buffers would mean that the packet buffer size for the NIC would have to
be restricted to 2048 - 320 - 256 = 1472B. However, this is problematic
for two reasons: first, 1472 is not a packet buffer size accepted by
GVE; second, at least 1474B of buffer space is needed to accommodate an
MTU of 1460, which is the default on GCP. As such, we allocate 4K
buffers, and post a 2K section of those 4K buffers (offset relative to
the XDP headroom) to the NIC for DMA to avoid a potential extra copy.
Because the GQ-QPL datapath requires copies regardless, this change was
not needed to support XDP in that case.
To capture this subtlety, a new field, packet_buffer_truesize, has been
added to the rx ring struct to represent size of the allocated buffer,
while packet_buffer_size has been left to represent the portion of the
buffer posted to the NIC.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Praveen Kaligineedi <pkaligineedi@google.com>
Signed-off-by: Joshua Washington <joshwash@google.com>
Signed-off-by: Harshitha Ramamurthy <hramamurthy@google.com>
Link: https://patch.msgid.link/20250321002910.1343422-6-hramamurthy@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
show more ...
|
| 904effd0 | 21-Mar-2025 |
Joshua Washington <joshwash@google.com> |
gve: merge packet buffer size fields
The data_buffer_size_dqo field in gve_priv and the packet_buffer_size
field in gve_rx_ring theoretically have the same meaning, but they are
defined in two diffe
gve: merge packet buffer size fields
The data_buffer_size_dqo field in gve_priv and the packet_buffer_size
field in gve_rx_ring theoretically have the same meaning, but they are
defined in two different places and used in two separate contexts. There
is no good reason for this, so this change merges those fields into the
packet_buffer_size field in the RX ring.
This change also introduces a packet_buffer_size field to struct
gve_rx_queue_config to account for cases where queues are not allocated,
such as when the interface is down.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Joshua Washington <joshwash@google.com>
Signed-off-by: Harshitha Ramamurthy <hramamurthy@google.com>
Link: https://patch.msgid.link/20250321002910.1343422-5-hramamurthy@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
show more ...
|
| 57a070c2 | 21-Mar-2025 |
Joshua Washington <joshwash@google.com> |
gve: update GQ RX to use buf_size
Commit ebdfae0d377b ("gve: adopt page pool for DQ RDA mode") introduced
a buf_size field to the gve_rx_slot_page_info struct, which can be used
in the datapath to t
gve: update GQ RX to use buf_size
Commit ebdfae0d377b ("gve: adopt page pool for DQ RDA mode") introduced
a buf_size field to the gve_rx_slot_page_info struct, which can be used
in the datapath to take the place of the packet_buffer_size field, as it
will already be hot in the cache due to its extensive use. Using the
buf_size field in the datapath frees up the packet_buffer_size field in
the GQ-specific RX cacheline to be generalized for GQ and DQ (in the
next patch), as there is currently no common packet buffer size field
between the two queue formats.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Joshua Washington <joshwash@google.com>
Signed-off-by: Harshitha Ramamurthy <hramamurthy@google.com>
Link: https://patch.msgid.link/20250321002910.1343422-4-hramamurthy@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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|
| 542a58f1 | 21-Mar-2025 |
Joshua Washington <joshwash@google.com> |
gve: introduce config-based allocation for XDP
An earlier patch series[1] introduced RX/TX ring allocation configuration
structs which contained metadata used to allocate and configure new RX
and TX
gve: introduce config-based allocation for XDP
An earlier patch series[1] introduced RX/TX ring allocation configuration
structs which contained metadata used to allocate and configure new RX
and TX rings. This led to a much cleaner and safer allocation pattern
wherein queue resources were not deallocated until new queue resources
were successfully allocated.
Migrate the XDP allocation path to use the same pattern to allow for the
existence of a single allocation path instead of relying on XDP-specific
allocation methods. These extra allocation methods result in the
duplication of many existing behaviors while being prone to error when
configuration changes unrelated to XDP occur.
Link: https://lore.kernel.org/netdev/20240122182632.1102721-1-shailend@google.com/ [1]
Reviewed-by: Praveen Kaligineedi <pkaligineedi@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Joshua Washington <joshwash@google.com>
Signed-off-by: Harshitha Ramamurthy <hramamurthy@google.com>
Link: https://patch.msgid.link/20250321002910.1343422-3-hramamurthy@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
show more ...
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