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dingtianhong 87e09cdec4 PCI: Disable Relaxed Ordering for some Intel processors
According to the Intel spec section 3.9.1 said:

    3.9.1 Optimizing PCIe Performance for Accesses Toward Coherent Memory
          and Toward MMIO Regions (P2P)

    In order to maximize performance for PCIe devices in the processors
    listed in Table 3-6 below, the soft- ware should determine whether the
    accesses are toward coherent memory (system memory) or toward MMIO
    regions (P2P access to other devices). If the access is toward MMIO
    region, then software can command HW to set the RO bit in the TLP
    header, as this would allow hardware to achieve maximum throughput for
    these types of accesses. For accesses toward coherent memory, software
    can command HW to clear the RO bit in the TLP header (no RO), as this
    would allow hardware to achieve maximum throughput for these types of
    accesses.

    Table 3-6. Intel Processor CPU RP Device IDs for Processors Optimizing
               PCIe Performance

    Processor                            CPU RP Device IDs

    Intel Xeon processors based on       6F01H-6F0EH
    Broadwell microarchitecture

    Intel Xeon processors based on       2F01H-2F0EH
    Haswell microarchitecture

It means some Intel processors has performance issue when use the Relaxed
Ordering Attribute, so disable Relaxed Ordering for these root port.

Signed-off-by: Casey Leedom <leedom@chelsio.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-14 22:14:50 -07:00
arch Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc 2017-08-10 09:36:06 -07:00
block
certs
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Documentation Pin control fixes for the v4.13 cycle: 2017-08-09 14:30:34 -07:00
drivers PCI: Disable Relaxed Ordering for some Intel processors 2017-08-14 22:14:50 -07:00
firmware
fs Changes since last update: 2017-08-07 18:16:22 -07:00
include PCI: Disable PCIe Relaxed Ordering if unsupported 2017-08-14 22:14:50 -07:00
init
ipc
kernel futex: Remove unnecessary warning from get_futex_key 2017-08-09 14:00:54 -07:00
lib
mm
net tipc: avoid inheriting msg_non_seq flag when message is returned 2017-08-14 11:20:36 -07:00
samples
scripts parse-maintainers: Move matching sections from MAINTAINERS 2017-08-08 11:16:14 -07:00
security
sound
tools bpf: fix selftest/bpf/test_pkt_md_access on s390x 2017-08-07 10:06:27 -07:00
usr
virt
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
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Kconfig
MAINTAINERS Pin control fixes for the v4.13 cycle: 2017-08-09 14:30:34 -07:00
Makefile Linux 4.13-rc4 2017-08-06 18:44:49 -07:00
README

Linux kernel
============

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.