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  1. 16 11月, 2017 1 次提交
    • M
      mm: remove __GFP_COLD · 453f85d4
      由 Mel Gorman 提交于 
      As the page free path makes no distinction between cache hot and cold
pages, there is no real useful ordering of pages in the free list that
allocation requests can take advantage of.  Juding from the users of
__GFP_COLD, it is likely that a number of them are the result of copying
other sites instead of actually measuring the impact.  Remove the
__GFP_COLD parameter which simplifies a number of paths in the page
allocator.

This is potentially controversial but bear in mind that the size of the
per-cpu pagelists versus modern cache sizes means that the whole per-cpu
list can often fit in the L3 cache.  Hence, there is only a potential
benefit for microbenchmarks that alloc/free pages in a tight loop.  It's
even worse when THP is taken into account which has little or no chance
of getting a cache-hot page as the per-cpu list is bypassed and the
zeroing of multiple pages will thrash the cache anyway.

The truncate microbenchmarks are not shown as this patch affects the
allocation path and not the free path.  A page fault microbenchmark was
tested but it showed no sigificant difference which is not surprising
given that the __GFP_COLD branches are a miniscule percentage of the
fault path.

Link: http://lkml.kernel.org/r/20171018075952.10627-9-mgorman@techsingularity.netSigned-off-by: NMel Gorman <mgorman@techsingularity.net>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      453f85d4
  3. 05 11月, 2017 2 次提交
  5. 02 11月, 2017 2 次提交
  7. 27 10月, 2017 1 次提交
  9. 11 10月, 2017 1 次提交
  11. 27 9月, 2017 2 次提交
    • D
      bpf, nfp: add meta data support · 65d88fd0
      由 Daniel Borkmann 提交于 
      Implement support for transferring XDP meta data into skb for
nfp driver; before calling into the program, xdp.data_meta points
to xdp.data, where on program return with pass verdict, we call
into skb_metadata_set().
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      65d88fd0
    • D
      bpf: add meta pointer for direct access · de8f3a83
      由 Daniel Borkmann 提交于 
      This work enables generic transfer of metadata from XDP into skb. The
basic idea is that we can make use of the fact that the resulting skb
must be linear and already comes with a larger headroom for supporting
bpf_xdp_adjust_head(), which mangles xdp->data. Here, we base our work
on a similar principle and introduce a small helper bpf_xdp_adjust_meta()
for adjusting a new pointer called xdp->data_meta. Thus, the packet has
a flexible and programmable room for meta data, followed by the actual
packet data. struct xdp_buff is therefore laid out that we first point
to data_hard_start, then data_meta directly prepended to data followed
by data_end marking the end of packet. bpf_xdp_adjust_head() takes into
account whether we have meta data already prepended and if so, memmove()s
this along with the given offset provided there's enough room.

xdp->data_meta is optional and programs are not required to use it. The
rationale is that when we process the packet in XDP (e.g. as DoS filter),
we can push further meta data along with it for the XDP_PASS case, and
give the guarantee that a clsact ingress BPF program on the same device
can pick this up for further post-processing. Since we work with skb
there, we can also set skb->mark, skb->priority or other skb meta data
out of BPF, thus having this scratch space generic and programmable
allows for more flexibility than defining a direct 1:1 transfer of
potentially new XDP members into skb (it's also more efficient as we
don't need to initialize/handle each of such new members). The facility
also works together with GRO aggregation. The scratch space at the head
of the packet can be multiple of 4 byte up to 32 byte large. Drivers not
yet supporting xdp->data_meta can simply be set up with xdp->data_meta
as xdp->data + 1 as bpf_xdp_adjust_meta() will detect this and bail out,
such that the subsequent match against xdp->data for later access is
guaranteed to fail.

The verifier treats xdp->data_meta/xdp->data the same way as we treat
xdp->data/xdp->data_end pointer comparisons. The requirement for doing
the compare against xdp->data is that it hasn't been modified from it's
original address we got from ctx access. It may have a range marking
already from prior successful xdp->data/xdp->data_end pointer comparisons
though.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      de8f3a83
  13. 04 9月, 2017 1 次提交
  15. 26 8月, 2017 1 次提交
  17. 24 8月, 2017 2 次提交
  19. 19 8月, 2017 1 次提交
  21. 02 8月, 2017 1 次提交
  23. 26 7月, 2017 1 次提交
  25. 05 7月, 2017 1 次提交
    • J
      nfp: default to chained metadata prepend format · 64a919a9
      由 Jakub Kicinski 提交于 
      ABI 4.x introduced the chained metadata format and made it the
only one possible.  There are cases, however, where the old
format is preferred - mostly to make interoperation with VFs
using ABI 3.x easier for the datapath.  In ABI 5.x we allowed
for more flexibility by selecting the metadata format based
on capabilities.  The default was left to non-chained.

In case of fallback traffic, there is no capability telling the
driver there may be chained metadata.  With a very stripped-
-down FW the default old metadata format would be selected
making the driver drop all fallback traffic.

This patch changes the default selection in the driver. It
should not hurt with old firmwares, because if they don't
advertise RSS they will not produce metadata anyway.  New
firmwares advertising ABI 5.x, however, can depend on the
driver defaulting to chained format.

Fixes: f9380629 ("nfp: advertise support for NFD ABI 0.5")
Suggested-by: NMichael Rapson <michael.rapson@netronome.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      64a919a9
  27. 01 7月, 2017 2 次提交
  29. 25 6月, 2017 1 次提交
  31. 24 6月, 2017 5 次提交
  33. 19 6月, 2017 1 次提交
  35. 16 6月, 2017 1 次提交
  37. 08 6月, 2017 9 次提交
  39. 01 6月, 2017 3 次提交
  41. 30 5月, 2017 1 次提交