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Revision d9a047aeffcef5755952d18f2901d8777d84019d authored by Doug Ledford on 09 July 2015, 14:21:08 UTC, committed by Doug Ledford on 14 July 2015, 17:20:15 UTC 
IB/mlx4: Optimize do_slave_init
 
There is little chance our memory allocation will fail, so we can
combine initializing the work structs with allocating them instead of
looping through all of them once to allocate and again to initialize.
Then when we need to actually find out if our device is up or in the
process of going down, have all of our work structs batched up, take the
spin_lock once and only once, and do all of the batch under the one
spin_lock invocation instead of incurring all of the locked memory cycles
we would otherwise incur to take/release the spin_lock over and over
again.

Signed-off-by: Doug Ledford <dledford@redhat.com>
1 parent 9bbf282
Raw File
cmdline-partition.txt 
Embedded device command line partition parsing
=====================================================================

Support for reading the block device partition table from the command line.
It is typically used for fixed block (eMMC) embedded devices.
It has no MBR, so saves storage space. Bootloader can be easily accessed
by absolute address of data on the block device.
Users can easily change the partition.

The format for the command line is just like mtdparts:

blkdevparts=<blkdev-def>[;<blkdev-def>]
  <blkdev-def> := <blkdev-id>:<partdef>[,<partdef>]
    <partdef> := <size>[@<offset>](part-name)

<blkdev-id>
    block device disk name, embedded device used fixed block device,
    it's disk name also fixed. such as: mmcblk0, mmcblk1, mmcblk0boot0.

<size>
    partition size, in bytes, such as: 512, 1m, 1G.

<offset>
    partition start address, in bytes.

(part-name)
    partition name, kernel send uevent with "PARTNAME". application can create
    a link to block device partition with the name "PARTNAME".
    user space application can access partition by partition name.

Example:
    eMMC disk name is "mmcblk0" and "mmcblk0boot0"

  bootargs:
    'blkdevparts=mmcblk0:1G(data0),1G(data1),-;mmcblk0boot0:1m(boot),-(kernel)'

  dmesg:
    mmcblk0: p1(data0) p2(data1) p3()
    mmcblk0boot0: p1(boot) p2(kernel)
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