Description of problem:

bdflush(2) is introduced as related man pages, but this syscall is obsolete and man pages don't say about the situation.

This may cause some useless time in tuning process.  Please remove the reference or add some notes like "this system call is obsolete and calling it is ignored, but this man pages is informative for understanding kernel behaviour."  

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
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Actual results:


Expected results:


Additional info:

in linux/fs/buffer.c: 
-----------------------------------
/*
 * There are no bdflush tunables left.  But distributions are
 * still running obsolete flush daemons, so we terminate them here.
 *
 * Use of bdflush() is deprecated and will be removed in a future kernel.
 * The `flush-X' kernel threads fully replace bdflush daemons and this call.
 */
SYSCALL_DEFINE2(bdflush, int, func, long, data)
{
-----------------------------------