mirror of
https://github.com/torvalds/linux.git
synced 2025-12-07 20:06:24 +00:00
e93a977367
This change reverts aba3a882a1: "mtd: spi-nor: intel: provide a range
for poll_timout". That change introduces a performance regression when
reading sequentially from flash. Logging calls to intel_spi_read without
this change we get:
Start MTD read
[ 20.045527] intel_spi_read(from=1800000, len=400000)
[ 20.045527] intel_spi_read(from=1800000, len=400000)
[ 282.199274] intel_spi_read(from=1c00000, len=400000)
[ 282.199274] intel_spi_read(from=1c00000, len=400000)
[ 544.351528] intel_spi_read(from=2000000, len=400000)
[ 544.351528] intel_spi_read(from=2000000, len=400000)
End MTD read
With this change:
Start MTD read
[ 21.942922] intel_spi_read(from=1c00000, len=400000)
[ 21.942922] intel_spi_read(from=1c00000, len=400000)
[ 23.784058] intel_spi_read(from=2000000, len=400000)
[ 23.784058] intel_spi_read(from=2000000, len=400000)
[ 25.625006] intel_spi_read(from=2400000, len=400000)
[ 25.625006] intel_spi_read(from=2400000, len=400000)
End MTD read
Signed-off-by: Luis Alberto Herrera <luisalberto@google.com>
Tested-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Link: https://lore.kernel.org/r/20200610224652.64336-1-luisalberto@google.com
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
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.