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Kernel enforces the alignment of the bottom of the stack, NFP
deals with positive offsets better so we should align the top
of the stack. Round the stack size to NFP word size (4B).
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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To allow verifier instruction callbacks without any extra locking
NETDEV_UNREGISTER notification would wait on a waitqueue for verifier
to finish. This design decision was made when rtnl lock was providing
all the locking. Use the read/write lock instead and remove the
workqueue.
Verifier will now call into the offload code, so dev_ops are moved
to offload structure. Since verifier calls are all under
bpf_prog_is_dev_bound() we no longer need static inline implementations
to please builds with CONFIG_NET=n.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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After TC offloads were converted to callbacks we have no choice
but keep track of the offloaded filter in the driver.
Since this change came a little late in the release cycle
there were a number of conflicts and allocation of vNIC priv
structure seems to have slipped away in linux-next.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Lots of overlapping changes. Also on the net-next side
the XDP state management is handled more in the generic
layers so undo the 'net' nfp fix which isn't applicable
in net-next.
Include a necessary change by Jakub Kicinski, with log message:
====================
cls_bpf no longer takes care of offload tracking. Make sure
netdevsim performs necessary checks. This fixes a warning
caused by TC trying to remove a filter it has not added.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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After TC offloads were converted to callbacks we have no choice
but keep track of the offloaded filter in the driver.
The check for nn->dp.bpf_offload_xdp was a stop gap solution
to make sure failed TC offload won't disable XDP, it's no longer
necessary. nfp_net_bpf_offload() will return -EBUSY on
TC vs XDP conflicts.
Fixes: 3f7889c4c79b ("net: sched: cls_bpf: call block callbacks for offload")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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cls_bpf used to take care of tracking what offload state a filter
is in, i.e. it would track if offload request succeeded or not.
This information would then be used to issue correct requests to
the driver, e.g. requests for statistics only on offloaded filters,
removing only filters which were offloaded, using add instead of
replace if previous filter was not added etc.
This tracking of offload state no longer functions with the new
callback infrastructure. There could be multiple entities trying
to offload the same filter.
Throw out all the tracking and corresponding commands and simply
pass to the drivers both old and new bpf program. Drivers will
have to deal with offload state tracking by themselves.
Fixes: 3f7889c4c79b ("net: sched: cls_bpf: call block callbacks for offload")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Build bot reported warning about invalid printk formats on 32bit
architectures. Use %zu for size_t and %zd ptr diff.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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If the program is simple and has only one adjust head call
with constant parameters, we can check that the call will
always succeed at translation time. We need to track the
location of the call and make sure parameters are always
the same. We also have to check the parameters against
datapath constraints and ETH_HLEN.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Support bpf_xdp_adjust_head(). We need to check whether the
packet offset after adjustment is within datapath's limits.
We also check if the frame is at least ETH_HLEN long (similar
to the kernel implementation).
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Add skeleton of verifier checks and translation handler
for call instructions. Make sure jump target resolution
will not treat them as jumps.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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BPF FW creates a run time symbol called bpf_capabilities which
contains TLV-formatted capability information. Allocate app
private structure to store parsed capabilities and add a skeleton
of parsing logic.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Since day one of XDP drivers had to remember to free the program
on the remove path. This leads to code duplication and is error
prone. Make the stack query the installed programs on unregister
and if something is installed, remove the program. Freeing of
program attached to XDP generic is moved from free_netdev() as well.
Because the remove will now be called before notifiers are
invoked, BPF offload state of the program will not get destroyed
before uninstall.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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This patch add the optimization frontend, but adding a new eBPF IR scan
pass "nfp_bpf_opt_ldst_gather".
The pass will traverse the IR to recognize the load/store pairs sequences
that come from lowering of memory copy builtins.
The gathered memory copy information will be kept in the meta info
structure of the first load instruction in the sequence and will be
consumed by the optimization backend added in the previous patches.
NOTE: a sequence with cross memory access doesn't qualify this
optimization, i.e. if one load in the sequence will load from place that
has been written by previous store. This is because when we turn the
sequence into single CPP operation, we are reading all contents at once
into NFP transfer registers, then write them out as a whole. This is not
identical with what the original load/store sequence is doing.
Detecting cross memory access for two random pointers will be difficult,
fortunately under XDP/eBPF's restrictied runtime environment, the copy
normally happen among map, packet data and stack, they do not overlap with
each other.
And for cases supported by NFP, cross memory access will only happen on
PTR_TO_PACKET. Fortunately for this, there is ID information that we could
do accurate memory alias check.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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When the gathered copy length is bigger than 32-bytes and within 128-bytes
(the maximum length a single CPP Pull/Push request can finish), the
strategy of read/write are changeed into:
* Read.
- use direct reference mode when length is within 32-bytes.
- use indirect mode when length is bigger than 32-bytes.
* Write.
- length <= 8-bytes
use write8 (direct_ref).
- length <= 32-byte and 4-bytes aligned
use write32 (direct_ref).
- length <= 32-bytes but not 4-bytes aligned
use write8 (indirect_ref).
- length > 32-bytes and 4-bytes aligned
use write32 (indirect_ref).
- length > 32-bytes and not 4-bytes aligned and <= 40-bytes
use write32 (direct_ref) to finish the first 32-bytes.
use write8 (direct_ref) to finish all remaining hanging part.
- length > 32-bytes and not 4-bytes aligned
use write32 (indirect_ref) to finish those 4-byte aligned parts.
use write8 (direct_ref) to finish all remaining hanging part.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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For NFP, we want to re-group a sequence of load/store pairs lowered from
memcpy/memmove into single memory bulk operation which then could be
accelerated using NFP CPP bus.
This patch extends the existing load/store auxiliary information by adding
two new fields:
struct bpf_insn *paired_st;
s16 ldst_gather_len;
Both fields are supposed to be carried by the the load instruction at the
head of the sequence. "paired_st" is the corresponding store instruction at
the head and "ldst_gather_len" is the gathered length.
If "ldst_gather_len" is negative, then the sequence is doing memory
load/store in descending order, otherwise it is in ascending order. We need
this information to detect overlapped memory access.
This patch then optimize memory bulk copy when the copy length is within
32-bytes.
The strategy of read/write used is:
* Read.
Use read32 (direct_ref), always.
* Write.
- length <= 8-bytes
write8 (direct_ref).
- length <= 32-bytes and is 4-byte aligned
write32 (direct_ref).
- length <= 32-bytes but is not 4-byte aligned
write8 (indirect_ref).
NOTE: the optimization should not change program semantics. The destination
register of the last load instruction should contain the same value before
and after this optimization.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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It is usual that we need to check if one BPF insn is for loading/storeing
data from/to memory.
Therefore, it makes sense to factor out related code to become common
helper functions.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Add support for emitting commands with field overwrites.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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When immed is used with No-Dest, the emitter should use reg.dst instead of
reg.areg for the destination, using the latter will actually encode
register zero.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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If any of the shift insns in the ld/shift sequence is jump destination,
don't do combination.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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If the mask insn in the ld/mask pair is jump destination, then don't do
combination.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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NFP eBPF offload JIT engine is doing some instruction combine based
optimizations which however must not be safe if the combined sequences
are across basic block boarders.
Currently, there are post checks during fixing jump destinations. If the
jump destination is found to be eBPF insn that has been combined into
another one, then JIT engine will raise error and abort.
This is not optimal. The JIT engine ought to disable the optimization on
such cross-bb-border sequences instead of abort.
As there is no control flow information in eBPF infrastructure that we
can't do basic block based optimizations, this patch extends the existing
jump destination record pass to also flag the jump destination, then in
instruction combine passes we could skip the optimizations if insns in the
sequence are jump targets.
Suggested-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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eBPF insns are internally organized as dual-list inside NFP offload JIT.
Random access to an insn needs to be done by either forward or backward
traversal along the list.
One place we need to do such traversal is at nfp_fixup_branches where one
traversal is needed for each jump insn to find the destination. Such
traversals could be avoided if jump destinations are collected through a
single travesal in a pre-scan pass, and such information could also be
useful in other places where jump destination info are needed.
This patch adds such jump destination collection in nfp_prog_prepare.
Suggested-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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This patch adds support for backward jump on NFP.
- restrictions on backward jump in various functions have been removed.
- nfp_fixup_branches now supports backward jump.
There is one thing to note, currently an input eBPF JMP insn may generate
several NFP insns, for example,
NFP imm move insn A \
NFP compare insn B --> 3 NFP insn jited from eBPF JMP insn M
NFP branch insn C /
---
NFP insn X --> 1 NFP insn jited from eBPF insn N
---
...
therefore, we are doing sanity check to make sure the last jited insn from
an eBPF JMP is a NFP branch instruction.
Once backward jump is allowed, it is possible an eBPF JMP insn is at the
end of the program. This is however causing trouble for the sanity check.
Because the sanity check requires the end index of the NFP insns jited from
one eBPF insn while only the start index is recorded before this patch that
we can only get the end index by:
start_index_of_the_next_eBPF_insn - 1
or for the above example:
start_index_of_eBPF_insn_N (which is the index of NFP insn X) - 1
nfp_fixup_branches was using nfp_for_each_insn_walk2 to expose *next* insn
to each iteration during the traversal so the last index could be
calculated from which. Now, it needs some extra code to handle the last
insn. Meanwhile, the use of walk2 is actually unnecessary, we could simply
use generic single instruction walk to do this, the next insn could be
easily calculated using list_next_entry.
So, this patch migrates the jump fixup traversal method to
*list_for_each_entry*, this simplifies the code logic a little bit.
The other thing to note is a new state variable "last_bpf_off" is
introduced to track the index of the last jited NFP insn. This is necessary
because NFP is generating special purposes epilogue sequences, so the index
of the last jited NFP insn is *not* always nfp_prog->prog_len - 1.
Suggested-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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With TC shared block changes we can't depend on correct netdev
pointer being available in cls_bpf. Move the device validation
to the driver. Core will only make sure that offloaded programs
are always attached in the driver (or in HW by the driver). We
trust that drivers which implement offload callbacks will perform
necessary checks.
Moving the checks to the driver is generally a useful thing,
in practice the check should be against a switchdev instance,
not a netdev, given that most ASICs will probably allow using
the same program on many ports.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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Following steps are taken in the driver to offload an XDP program:
XDP_SETUP_PROG:
* prepare:
- allocate program state;
- run verifier (bpf_analyzer());
- run translation;
* load:
- stop old program if needed;
- load program;
- enable BPF if not enabled;
* clean up:
- free program image.
With new infrastructure the flow will look like this:
BPF_OFFLOAD_VERIFIER_PREP:
- allocate program state;
BPF_OFFLOAD_TRANSLATE:
- run translation;
XDP_SETUP_PROG:
- stop old program if needed;
- load program;
- enable BPF if not enabled;
BPF_OFFLOAD_DESTROY:
- free program image.
Take advantage of the new infrastructure. Allocation of driver
metadata has to be moved from jit.c to offload.c since it's now
done at a different stage. Since there is no separate driver
private data for verification step, move temporary nfp_meta
pointer into nfp_prog. We will now use user space context
offsets.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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struct nfp_prog is currently only used internally by the translator.
This means there is a lot of parameter passing going on, between
the translator and different stages of offload. Simplify things
by allocating nfp_prog in offload.c already.
We will now use kmalloc() to allocate the program area and only
DMA map it for the time of loading (instead of allocating DMA
coherent memory upfront).
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Most of offload/translation prepare logic will be moved to
offload.c. To help git generate more reasonable diffs
move nfp_prog_prepare() and nfp_prog_free() functions
there as a first step.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Firmware supports live replacement of programs for quite some
time now. Remove the software-fallback related logic and
depend on the FW for program replace. Seamless reload will
become a requirement if maps are present, anyway.
Load and start stages have to be split now, since replace
only needs a load, start has already been done on add.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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We currently create a fake cls_bpf offload object when we want
to offload XDP. Simplify and clarify the code by moving the
TC/XDP specific logic out of common offload code. This is easy
now that we don't support legacy TC actions. We only need the
bpf program and state of the skip_sw flag.
Temporarily set @code to NULL in nfp_net_bpf_offload(), compilers
seem to have trouble recognizing it's always initialized. Next
patches will eliminate that variable.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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BPF offload's main header does not need to include nfp_net.h.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The register renumbering was removed and will not be coming back
in its old, naive form, given that it would be fundamentally
incompatible with calling functions. Remove the leftovers.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Only support BPF_PROG_TYPE_SCHED_CLS programs in direct
action mode. This simplifies preparing the offload since
there will now be only one mode of operation for that type
of program. We need to know the attachment mode type of
cls_bpf programs, because exit codes are interpreted
differently for legacy vs DA mode.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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If kernel config does not include BPF just replace the BPF
app handler with the handler for basic NIC. The BPF app
will now be built only if BPF infrastructure is selected
in kernel config.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Recent TC changes dropped the check protecting us from trying
to offload a TC program if XDP programs are already loaded.
Fixes: 90d97315b3e7 ("nfp: bpf: Convert ndo_setup_tc offloads to block callbacks")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch supports BPF_NEG under both BPF_ALU64 and BPF_ALU. LLVM recently
starts to generate it.
NOTE: BPF_NEG takes single operand which is an register and serve as both
input and output.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The current ALU_OP_NEG is Op encoding 0x4 for NPF ALU instruction. It is
actually performing "~B" operation which is bitwise NOT.
The using naming ALU_OP_NEG is misleading as NEG is -B which is not the
same as ~B.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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phase
This restores the original behaviour before the block callbacks were
introduced. Allow the drivers to do binding of block always, no matter
if the NETIF_F_HW_TC feature is on or off. Move the check to the block
callback which is called for rule insertion.
Reported-by: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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the verifier got progressively smarter over time and size of its internal
state grew as well. Time to reduce the memory consumption.
Before:
sizeof(struct bpf_verifier_state) = 6520
After:
sizeof(struct bpf_verifier_state) = 896
It's done by observing that majority of BPF programs use little to
no stack whereas verifier kept all of 512 stack slots ready always.
Instead dynamically reallocate struct verifier state when stack
access is detected.
Runtime difference before vs after is within a noise.
The number of processed instructions stays the same.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Simon Horman <simon.horman@netronome.com>
Cc: oss-drivers@netronome.com
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Loading 64bit constants require up to 4 load immediates, since
we can only load 16 bits at a time. If the 32bit halves of
the 64bit constant are the same, however, we can save a cycle
by doing a register move instead of two loads of 16 bits.
Note that we don't optimize the normal ALU64 load because even
though it's a 64 bit load the upper half of the register is
a coming from sign extension so we can load it in one cycle
anyway.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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If stack pointer has a different value on different paths
but the alignment to words (4B) remains the same, we can
set a new LMEM access pointer to the calculated value and
access whichever word it's pointing to.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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To access beyond 64th byte of the stack we need to set a new
stack pointer register (LMEM is accessed indirectly through
those pointers). Add a function for encoding local CSR access
instruction. Use stack pointer number 3.
Note that stack pointer registers allow us to index into 32
bytes of LMEM (with shift operations i.e. when operands are
restricted). This means if access is crossing 32 byte boundary
we must not use offsetting, we have to set the pointer to the
exact address and move it with post-increments.
We depend on the datapath placing the stack base address in
GPR A22 for our use.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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As long as the verifier tells us the stack offset exactly we
can render the LMEM reads quite easily. Simply make sure that
the offset is constant for a given instruction and add it to
the instruction's offset.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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When we are performing unaligned stack accesses in the 32-64B window
we have to do a read-modify-write cycle. E.g. for reading 8 bytes
from address 17:
0: tmp = stack[16]
1: gprLo = tmp >> 8
2: tmp = stack[20]
3: gprLo |= tmp << 24
4: tmp = stack[20]
5: gprHi = tmp >> 8
6: tmp = stack[24]
7: gprHi |= tmp << 24
The load on line 4 is unnecessary, because tmp already contains data
from stack[20].
For write we can optimize both loads and writebacks away.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Add simple stack read support, similar to write in every aspect,
but data flowing the other way. Note that unlike write which can
be done in smaller than word quantities, if registers are loaded
with less-than-word of stack contents - the values have to be
zero extended.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Stack is implemented by the LMEM register file. Unaligned accesses
to LMEM are not allowed. Accesses also have to be 4B wide.
To support stack we need to make sure offsets of pointers are known
at translation time (for now) and perform correct load/mask/shift
operations.
Since we can access first 64B of LMEM without much effort support
only stacks not bigger than 64B. Following commits will extend
the possible sizes beyond that.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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nfp_bpf_check_ptr() mostly looks at the pointer register.
Add a temporary variable to shorten the code.
While at it make sure we print error messages if translation
fails to help users identify the problem (to be carried in
ext_ack in due course).
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The need to emitting a few nops will become more common soon
as we add stack and map support. Add a helper. This allows
for code to be shorter but also may be handy for marking the
nops with a "reason" to ease applying optimizations.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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All drivers are converted to use block callbacks for TC_SETUP_CLS*.
So it is now safe to remove the calls to ndo_setup_tc from cls_*
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Benefit from the newly introduced block callback infrastructure and
convert ndo_setup_tc calls for bpf offloads to block callbacks.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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