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    init.h: remove __cpuinit sections from the kernel · 22f0a273
    Paul Gortmaker authored
    The __cpuinit type of throwaway sections might have made sense
    some time ago when RAM was more constrained, but now the savings
    do not offset the cost and complications.  For example, the fix in
    commit 5e427ec2 ("x86: Fix bit corruption at CPU resume time")
    is a good example of the nasty type of bugs that can be created
    with improper use of the various __init prefixes.
    
    After a discussion on LKML[1] it was decided that cpuinit should go
    the way of devinit and be phased out.  Once all the users are gone,
    we can then finally remove the macros themselves from linux/init.h.
    
    As an interim step, we can dummy out the macros to be no-ops, and
    this will allow us to avoid a giant tree-wide patch, and instead
    we can feed in smaller chunks mainly via the arch/ trees.  This
    is in keeping with commit 78d86c21
    ("init.h: Remove __dev* sections from the kernel")
    
    We don't strictly need to dummy out the macros to do this, but if
    we don't then some harmless section mismatch warnings may temporarily
    result.  For example, notify_cpu_starting() and cpu_up() are arch
    independent (kernel/cpu.c) and are flagged as __cpuinit.  And hence
    the calling functions in the arch specific code are also expected
    to be __cpuinit -- if not, then we get the section mismatch warning.
    
    Two of the three __CPUINIT variants are not used whatsoever, and
    so they are simply removed directly at this point in time.
    
    [1] https://lkml.org/lkml/2013/5/20/589
    
    
    
    Signed-off-by: default avatarPaul Gortmaker <paul.gortmaker@windriver.com>
    22f0a273