In current implementation, io_channel list will be accessed by
spdk_for_each_channel() and spdk_get_io_channel(). We will try to
accelerate spdk_get_io_channel() in the following change "thread: speed
up io_channel lookup by using rbtree" by changing io_channel from list
into RB tree.
To make it cleaner, we prefer to use ch->dev as the key for the
io_channel RB tree instead of ch->dev->io_device. This patch makes
spdk_for_each_channel() use the i->dev to find the expected io_channel.
And the io_device in structure spdk_io_channel_iter is not needed in
spdk_for_each_channel_continue() but we keep it for the compatibility of
spdk_io_channel_iter_get_io_device().
After this patch, spdk_for_each_channel() has to access both io_device
list and io_channel list, and spdk_for_each_channel_continue() still has
to access only io_channel list.
Both io_device list and io_channel list will become RB tree. Hence
performance degradation will be negligible. spdk_for_each_channel() is
not so performance critical than spdk_get_io_channel().
Signed-off-by: Jiewei Ke <jiewei@smartx.com>
Change-Id: Idd486b0aa1b63b57ede90527dcd1631cbb008a1a
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/8749
Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Community-CI: Mellanox Build Bot
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
e45450d28f