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  1. 16 6月, 2017 4 次提交
  3. 09 5月, 2017 1 次提交
    • M
      treewide: use kv[mz]alloc* rather than opencoded variants · 752ade68
      由 Michal Hocko 提交于 
      There are many code paths opencoding kvmalloc.  Let's use the helper
instead.  The main difference to kvmalloc is that those users are
usually not considering all the aspects of the memory allocator.  E.g.
allocation requests <= 32kB (with 4kB pages) are basically never failing
and invoke OOM killer to satisfy the allocation.  This sounds too
disruptive for something that has a reasonable fallback - the vmalloc.
On the other hand those requests might fallback to vmalloc even when the
memory allocator would succeed after several more reclaim/compaction
attempts previously.  There is no guarantee something like that happens
though.

This patch converts many of those places to kv[mz]alloc* helpers because
they are more conservative.

Link: http://lkml.kernel.org/r/20170306103327.2766-2-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> # Xen bits
Acked-by: NKees Cook <keescook@chromium.org>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Acked-by: Andreas Dilger <andreas.dilger@intel.com> # Lustre
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> # KVM/s390
Acked-by: Dan Williams <dan.j.williams@intel.com> # nvdim
Acked-by: David Sterba <dsterba@suse.com> # btrfs
Acked-by: Ilya Dryomov <idryomov@gmail.com> # Ceph
Acked-by: Tariq Toukan <tariqt@mellanox.com> # mlx4
Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx5
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Santosh Raspatur <santosh@chelsio.com>
Cc: Hariprasad S <hariprasad@chelsio.com>
Cc: Yishai Hadas <yishaih@mellanox.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: "Yan, Zheng" <zyan@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      752ade68
  5. 07 4月, 2017 1 次提交
  7. 10 3月, 2017 2 次提交
  9. 31 1月, 2017 1 次提交
  11. 09 12月, 2016 1 次提交
  13. 25 11月, 2016 1 次提交
    • E
      mlx4: reorganize struct mlx4_en_tx_ring · e3f42f84
      由 Eric Dumazet 提交于 
      Goal is to reorganize this critical structure to increase performance.

ndo_start_xmit() should only dirty one cache line, and access as few
cache lines as possible.

Add sp_ (Slow Path) prefix to fields that are not used in fast path,
to make clear what is going on.

After this patch pahole reports something much better, as all
ndo_start_xmit() needed fields are packed into two cache lines instead
of seven or eight

struct mlx4_en_tx_ring {
	u32                        last_nr_txbb;         /*     0   0x4 */
	u32                        cons;                 /*   0x4   0x4 */
	long unsigned int          wake_queue;           /*   0x8   0x8 */
	struct netdev_queue *      tx_queue;             /*  0x10   0x8 */
	u32                        (*free_tx_desc)(struct mlx4_en_priv *, struct mlx4_en_tx_ring *, int, u8, u64, int); /*  0x18   0x8 */
	struct mlx4_en_rx_ring *   recycle_ring;         /*  0x20   0x8 */

	/* XXX 24 bytes hole, try to pack */

	/* --- cacheline 1 boundary (64 bytes) --- */
	u32                        prod;                 /*  0x40   0x4 */
	unsigned int               tx_dropped;           /*  0x44   0x4 */
	long unsigned int          bytes;                /*  0x48   0x8 */
	long unsigned int          packets;              /*  0x50   0x8 */
	long unsigned int          tx_csum;              /*  0x58   0x8 */
	long unsigned int          tso_packets;          /*  0x60   0x8 */
	long unsigned int          xmit_more;            /*  0x68   0x8 */
	struct mlx4_bf             bf;                   /*  0x70  0x18 */
	/* --- cacheline 2 boundary (128 bytes) was 8 bytes ago --- */
	__be32                     doorbell_qpn;         /*  0x88   0x4 */
	__be32                     mr_key;               /*  0x8c   0x4 */
	u32                        size;                 /*  0x90   0x4 */
	u32                        size_mask;            /*  0x94   0x4 */
	u32                        full_size;            /*  0x98   0x4 */
	u32                        buf_size;             /*  0x9c   0x4 */
	void *                     buf;                  /*  0xa0   0x8 */
	struct mlx4_en_tx_info *   tx_info;              /*  0xa8   0x8 */
	int                        qpn;                  /*  0xb0   0x4 */
	u8                         queue_index;          /*  0xb4   0x1 */
	bool                       bf_enabled;           /*  0xb5   0x1 */
	bool                       bf_alloced;           /*  0xb6   0x1 */
	u8                         hwtstamp_tx_type;     /*  0xb7   0x1 */
	u8 *                       bounce_buf;           /*  0xb8   0x8 */
	/* --- cacheline 3 boundary (192 bytes) --- */
	long unsigned int          queue_stopped;        /*  0xc0   0x8 */
	struct mlx4_hwq_resources  sp_wqres;             /*  0xc8  0x58 */
	/* --- cacheline 4 boundary (256 bytes) was 32 bytes ago --- */
	struct mlx4_qp             sp_qp;                /* 0x120  0x30 */
	/* --- cacheline 5 boundary (320 bytes) was 16 bytes ago --- */
	struct mlx4_qp_context     sp_context;           /* 0x150  0xf8 */
	/* --- cacheline 9 boundary (576 bytes) was 8 bytes ago --- */
	cpumask_t                  sp_affinity_mask;     /* 0x248  0x20 */
	enum mlx4_qp_state         sp_qp_state;          /* 0x268   0x4 */
	u16                        sp_stride;            /* 0x26c   0x2 */
	u16                        sp_cqn;               /* 0x26e   0x2 */

	/* size: 640, cachelines: 10, members: 36 */
	/* sum members: 600, holes: 1, sum holes: 24 */
	/* padding: 16 */
};

Instead of this silly placement :

struct mlx4_en_tx_ring {
	u32                        last_nr_txbb;         /*     0   0x4 */
	u32                        cons;                 /*   0x4   0x4 */
	long unsigned int          wake_queue;           /*   0x8   0x8 */

	/* XXX 48 bytes hole, try to pack */

	/* --- cacheline 1 boundary (64 bytes) --- */
	u32                        prod;                 /*  0x40   0x4 */

	/* XXX 4 bytes hole, try to pack */

	long unsigned int          bytes;                /*  0x48   0x8 */
	long unsigned int          packets;              /*  0x50   0x8 */
	long unsigned int          tx_csum;              /*  0x58   0x8 */
	long unsigned int          tso_packets;          /*  0x60   0x8 */
	long unsigned int          xmit_more;            /*  0x68   0x8 */
	unsigned int               tx_dropped;           /*  0x70   0x4 */

	/* XXX 4 bytes hole, try to pack */

	struct mlx4_bf             bf;                   /*  0x78  0x18 */
	/* --- cacheline 2 boundary (128 bytes) was 16 bytes ago --- */
	long unsigned int          queue_stopped;        /*  0x90   0x8 */
	cpumask_t                  affinity_mask;        /*  0x98  0x10 */
	struct mlx4_qp             qp;                   /*  0xa8  0x30 */
	/* --- cacheline 3 boundary (192 bytes) was 24 bytes ago --- */
	struct mlx4_hwq_resources  wqres;                /*  0xd8  0x58 */
	/* --- cacheline 4 boundary (256 bytes) was 48 bytes ago --- */
	u32                        size;                 /* 0x130   0x4 */
	u32                        size_mask;            /* 0x134   0x4 */
	u16                        stride;               /* 0x138   0x2 */

	/* XXX 2 bytes hole, try to pack */

	u32                        full_size;            /* 0x13c   0x4 */
	/* --- cacheline 5 boundary (320 bytes) --- */
	u16                        cqn;                  /* 0x140   0x2 */

	/* XXX 2 bytes hole, try to pack */

	u32                        buf_size;             /* 0x144   0x4 */
	__be32                     doorbell_qpn;         /* 0x148   0x4 */
	__be32                     mr_key;               /* 0x14c   0x4 */
	void *                     buf;                  /* 0x150   0x8 */
	struct mlx4_en_tx_info *   tx_info;              /* 0x158   0x8 */
	struct mlx4_en_rx_ring *   recycle_ring;         /* 0x160   0x8 */
	u32                        (*free_tx_desc)(struct mlx4_en_priv *, struct mlx4_en_tx_ring *, int, u8, u64, int); /* 0x168   0x8 */
	u8 *                       bounce_buf;           /* 0x170   0x8 */
	struct mlx4_qp_context     context;              /* 0x178  0xf8 */
	/* --- cacheline 9 boundary (576 bytes) was 48 bytes ago --- */
	int                        qpn;                  /* 0x270   0x4 */
	enum mlx4_qp_state         qp_state;             /* 0x274   0x4 */
	u8                         queue_index;          /* 0x278   0x1 */
	bool                       bf_enabled;           /* 0x279   0x1 */
	bool                       bf_alloced;           /* 0x27a   0x1 */

	/* XXX 5 bytes hole, try to pack */

	/* --- cacheline 10 boundary (640 bytes) --- */
	struct netdev_queue *      tx_queue;             /* 0x280   0x8 */
	int                        hwtstamp_tx_type;     /* 0x288   0x4 */

	/* size: 704, cachelines: 11, members: 36 */
	/* sum members: 587, holes: 6, sum holes: 65 */
	/* padding: 52 */
};
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reviewed-by: NTariq Toukan <tariqt@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      e3f42f84
  15. 03 11月, 2016 2 次提交
    • T
      net/mlx4_en: Add ethtool statistics for XDP cases · 15fca2c8
      由 Tariq Toukan 提交于 
      XDP statistics are reported in ethtool, in total and per ring,
as follows:
- xdp_drop: the number of packets dropped by xdp.
- xdp_tx: the number of packets forwarded by xdp.
- xdp_tx_full: the number of times an xdp forward failed
	due to a full tx xdp ring.

In addition, all packets that are dropped/forwarded by XDP
are no longer accounted in rx_packets/rx_bytes of the ring,
so that they count traffic that is passed to the stack.
Signed-off-by: NTariq Toukan <tariqt@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      15fca2c8
    • T
      net/mlx4_en: Refactor the XDP forwarding rings scheme · 67f8b1dc
      由 Tariq Toukan 提交于 
      Separately manage the two types of TX rings: regular ones, and XDP.
Upon an XDP set, do not borrow regular TX rings and convert them
into XDP ones, but allocate new ones, unless we hit the max number
of rings.
Which means that in systems with smaller #cores we will not consume
the current TX rings for XDP, while we are still in the num TX limit.

XDP TX rings counters are not shown in ethtool statistics.
Instead, XDP counters will be added to the respective RX rings
in a downstream patch.

This has no performance implications.
Signed-off-by: NTariq Toukan <tariqt@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      67f8b1dc
  17. 12 9月, 2016 1 次提交
  19. 20 7月, 2016 2 次提交
    • B
      net/mlx4_en: add xdp forwarding and data write support · 9ecc2d86
      由 Brenden Blanco 提交于 
      A user will now be able to loop packets back out of the same port using
a bpf program attached to xdp hook. Updates to the packet contents from
the bpf program is also supported.

For the packet write feature to work, the rx buffers are now mapped as
bidirectional when the page is allocated. This occurs only when the xdp
hook is active.

When the program returns a TX action, enqueue the packet directly to a
dedicated tx ring, so as to avoid completely any locking. This requires
the tx ring to be allocated 1:1 for each rx ring, as well as the tx
completion running in the same softirq.

Upon tx completion, this dedicated tx ring recycles pages without
unmapping directly back to the original rx ring. In steady state tx/drop
workload, effectively 0 page allocs/frees will occur.

In order to separate out the paths between free and recycle, a
free_tx_desc func pointer is introduced that is optionally updated
whenever recycle_ring is activated. By default the original free
function is always initialized.
Signed-off-by: NBrenden Blanco <bblanco@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      9ecc2d86
    • B
      net/mlx4_en: break out tx_desc write into separate function · 224e92e0
      由 Brenden Blanco 提交于 
      In preparation for writing the tx descriptor from multiple functions,
create a helper for both normal and blueflame access.
Signed-off-by: NBrenden Blanco <bblanco@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      224e92e0
  21. 26 5月, 2016 1 次提交
  23. 06 5月, 2016 1 次提交
    • H
      net/mlx4: Avoid wrong virtual mappings · 73898db0
      由 Haggai Abramovsky 提交于 
      The dma_alloc_coherent() function returns a virtual address which can
be used for coherent access to the underlying memory.  On some
architectures, like arm64, undefined behavior results if this memory is
also accessed via virtual mappings that are not coherent.  Because of
their undefined nature, operations like virt_to_page() return garbage
when passed virtual addresses obtained from dma_alloc_coherent().  Any
subsequent mappings via vmap() of the garbage page values are unusable
and result in bad things like bus errors (synchronous aborts in ARM64
speak).

The mlx4 driver contains code that does the equivalent of:
vmap(virt_to_page(dma_alloc_coherent)), this results in an OOPs when the
device is opened.

Prevent Ethernet driver to run this problematic code by forcing it to
allocate contiguous memory. As for the Infiniband driver, at first we
are trying to allocate contiguous memory, but in case of failure roll
back to work with fragmented memory.
Signed-off-by: NHaggai Abramovsky <hagaya@mellanox.com>
Signed-off-by: NYishai Hadas <yishaih@mellanox.com>
Reported-by: NDavid Daney <david.daney@cavium.com>
Tested-by: NSinan Kaya <okaya@codeaurora.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      73898db0
  25. 05 5月, 2016 1 次提交
    • A
      net/mlx4_en: Add support for inner IPv6 checksum offloads and TSO · 09067122
      由 Alexander Duyck 提交于 
      >From what I can tell the ConnectX-3 will support an inner IPv6 checksum and
segmentation offload, however it cannot support outer IPv6 headers.  This
assumption is based on the fact that I could see the checksum being
offloaded for inner header on IPv4 tunnels, but not on IPv6 tunnels.

For this reason I am adding the feature to the hw_enc_features and adding
an extra check to the features_check call that will disable GSO and
checksum offload in the case that the encapsulated frame has an outer IP
version of that is not 4.  The check in mlx4_en_features_check could be
removed if at some point in the future a fix is found that allows the
hardware to offload segmentation/checksum on tunnels with an outer IPv6
header.
Signed-off-by: NAlexander Duyck <aduyck@mirantis.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      09067122
  27. 26 4月, 2016 1 次提交
  29. 14 3月, 2016 1 次提交
    • J
      mlx4: use napi_consume_skb API to get bulk free operations · b4a53379
      由 Jesper Dangaard Brouer 提交于 
      Bulk free of SKBs happen transparently by the API call napi_consume_skb().
The napi budget parameter is usually needed by napi_consume_skb()
to detect if called from netpoll.  In this patch it has an extra meaning.

For mlx4 driver, the mlx4_en_stop_port() call is done outside
NAPI/softirq context, and cleanup the entire TX ring via
mlx4_en_free_tx_buf().  The code mlx4_en_free_tx_desc() for
freeing SKBs are shared with NAPI calls.

To handle this shared use the zero budget indication is reused,
and handled appropriately in napi_consume_skb(). To reflect this,
variable is called napi_mode for the function call that needed
this distinction.
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      b4a53379
  31. 17 2月, 2016 1 次提交
    • H
      net/mlx4_core: Set UAR page size to 4KB regardless of system page size · 85743f1e
      由 Huy Nguyen 提交于 
      problem description:

The current code sets UAR page size equal to system page size.
The ConnectX-3 and ConnectX-3 Pro HWs require minimum 128 UAR pages.
The mlx4 kernel drivers are not loaded if there is less than 128 UAR pages.

solution:

Always set UAR page to 4KB. This allows more UAR pages if the OS
has PAGE_SIZE larger than 4KB. For example, PowerPC kernel use 64KB
system page size, with 4MB uar region, there are 4MB/2/64KB = 32
uars (half for uar, half for blueflame). This does not meet minimum 128
UAR pages requirement. With 4KB UAR page, there are 4MB/2/4KB = 512 uars
which meet the minimum requirement.

Note that only codes in mlx4_core that deal with firmware know that uar
page size is 4KB. Codes that deal with usr page in cq and qp context
(mlx4_ib, mlx4_en and part of mlx4_core) still have the same assumption
that uar page size equals to system page size.

Note that with this implementation, on 64KB system page size kernel, there
are 16 uars per system page but only one uars is used. The other 15
uars are ignored because of the above assumption.

Regarding SR-IOV, mlx4_core in hypervisor will set the uar page size
to 4KB and mlx4_core code in virtual OS will obtain the uar page size from
firmware.

Regarding backward compatibility in SR-IOV, if hypervisor has this new code,
the virtual OS must be updated. If hypervisor has old code, and the virtual
OS has this new code, the new code will be backward compatible with the
old code. If the uar size is big enough, this new code in VF continues to
work with 64 KB uar page size (on PowerPc kernel). If the uar size does not
meet 128 uars requirement, this new code not loaded in VF and print the same
error message as the old code in Hypervisor.
Signed-off-by: NHuy Nguyen <huyn@mellanox.com>
Reviewed-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      85743f1e
  33. 28 10月, 2015 1 次提交
  35. 28 7月, 2015 2 次提交
  37. 25 6月, 2015 2 次提交
  39. 28 5月, 2015 1 次提交
    • R
      cpumask_set_cpu_local_first => cpumask_local_spread, lament · f36963c9
      由 Rusty Russell 提交于 
      da91309e (cpumask: Utility function to set n'th cpu...) created a
genuinely weird function.  I never saw it before, it went through DaveM.
(He only does this to make us other maintainers feel better about our own
mistakes.)

cpumask_set_cpu_local_first's purpose is say "I need to spread things
across N online cpus, choose the ones on this numa node first"; you call
it in a loop.

It can fail.  One of the two callers ignores this, the other aborts and
fails the device open.

It can fail in two ways: allocating the off-stack cpumask, or through a
convoluted codepath which AFAICT can only occur if cpu_online_mask
changes.  Which shouldn't happen, because if cpu_online_mask can change
while you call this, it could return a now-offline cpu anyway.

It contains a nonsensical test "!cpumask_of_node(numa_node)".  This was
drawn to my attention by Geert, who said this causes a warning on Sparc.
It sets a single bit in a cpumask instead of returning a cpu number,
because that's what the callers want.

It could be made more efficient by passing the previous cpu rather than
an index, but that would be more invasive to the callers.

Fixes: da91309e
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (then rebased)
Tested-by: NAmir Vadai <amirv@mellanox.com>
Acked-by: NAmir Vadai <amirv@mellanox.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
      f36963c9
  41. 30 4月, 2015 1 次提交
  43. 10 4月, 2015 1 次提交
    • A
      mlx4/mlx5: Use dma_wmb/rmb where appropriate · 12b3375f
      由 Alexander Duyck 提交于 
      This patch should help to improve the performance of the mlx4 and mlx5 on a
number of architectures.  For example, on x86 the dma_wmb/rmb equates out
to a barrer() call as the architecture is already strong ordered, and on
PowerPC the call works out to a lwsync which is significantly less expensive
than the sync call that was being used for wmb.

I placed the new barriers between any spots that seemed to be trying to
order memory/memory reads or writes, if there are any spots that involved
MMIO I left the existing wmb in place as the new barriers cannot order
transactions between coherent and non-coherent memories.

v2: Reduced the replacments to just the spots where I could clearly
    identify the usage pattern.

Cc: Amir Vadai <amirv@mellanox.com>
Cc: Ido Shamay <idos@mellanox.com>
Cc: Eli Cohen <eli@mellanox.com>
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      12b3375f
  45. 26 1月, 2015 1 次提交
  47. 14 1月, 2015 1 次提交
  49. 23 12月, 2014 1 次提交
  51. 12 12月, 2014 1 次提交
    • E
      net/mlx4: Change QP allocation scheme · ddae0349
      由 Eugenia Emantayev 提交于 
      When using BF (Blue-Flame), the QPN overrides the VLAN, CV, and SV fields
in the WQE. Thus, BF may only be used for QPNs with bits 6,7 unset.

The current Ethernet driver code reserves a Tx QP range with 256b alignment.

This is wrong because if there are more than 64 Tx QPs in use,
QPNs >= base + 65 will have bits 6/7 set.

This problem is not specific for the Ethernet driver, any entity that
tries to reserve more than 64 BF-enabled QPs should fail. Also, using
ranges is not necessary here and is wasteful.

The new mechanism introduced here will support reservation for
"Eth QPs eligible for BF" for all drivers: bare-metal, multi-PF, and VFs
(when hypervisors support WC in VMs). The flow we use is:

1. In mlx4_en, allocate Tx QPs one by one instead of a range allocation,
   and request "BF enabled QPs" if BF is supported for the function

2. In the ALLOC_RES FW command, change param1 to:
a. param1[23:0]  - number of QPs
b. param1[31-24] - flags controlling QPs reservation

Bit 31 refers to Eth blueflame supported QPs. Those QPs must have
bits 6 and 7 unset in order to be used in Ethernet.

Bits 24-30 of the flags are currently reserved.

When a function tries to allocate a QP, it states the required attributes
for this QP. Those attributes are considered "best-effort". If an attribute,
such as Ethernet BF enabled QP, is a must-have attribute, the function has
to check that attribute is supported before trying to do the allocation.

In a lower layer of the code, mlx4_qp_reserve_range masks out the bits
which are unsupported. If SRIOV is used, the PF validates those attributes
and masks out unsupported attributes as well. In order to notify VFs which
attributes are supported, the VF uses QUERY_FUNC_CAP command. This command's
mailbox is filled by the PF, which notifies which QP allocation attributes
it supports.
Signed-off-by: NEugenia Emantayev <eugenia@mellanox.co.il>
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ddae0349
  53. 31 10月, 2014 2 次提交
  55. 09 10月, 2014 1 次提交
  57. 08 10月, 2014 1 次提交
  59. 06 10月, 2014 2 次提交