net/smc: Tune the maximum size of virtually contiguous sndbufs or RMBs for SMC-R

euleros inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I76JHC


CVE: NA

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If the receiver application reads data slower than the sender, the sender
may occur sending failures due to a full sndbufs, and the receiver may not
process the rmb timely which results in the sender unable to send data
immediately. Increasing the buffer size appropriately can help reduce the
probability of the above problems and increase throughput. Therefore, tune
the maximum size to 256M of virtually contiguous sndbufs or RMBs for SMC-R.

Signed-off-by: Litao Jiao <jiaolitao@sangfor.com.cn>