• Steven Rostedt's avatar
    x86: Prepare removal of previous_esp from i386 thread_info structure · 0788aa6a
    Steven Rostedt authored
    The i386 thread_info contains a previous_esp field that is used
    to daisy chain the different stacks for dump_stack()
    (ie. irq, softirq, thread stacks).
    
    The goal is to eventual make i386 handling of thread_info the same
    as x86_64, which means that the thread_info will not be in the stack
    but as a per_cpu variable. We will no longer depend on thread_info
    being able to daisy chain different stacks as it will only exist
    in one location (the thread stack).
    
    By moving previous_esp to the end of thread_info and referencing
    it as an offset instead of using a thread_info field, this becomes
    a stepping stone to moving the thread_info.
    
    The offset to get to the previous stack is rather ugly in this
    patch, but this is only temporary and the prev_esp will be changed
    in the next commit. This commit is more for sanity checks of the
    change.
    
    Cc: Andrew Morton <akpm@linux-foundation.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Brian Gerst <brgerst@gmail.com>
    Cc: Robert Richter <rric@kernel.org>
    Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
    Link: http://lkml.kernel.org/r/20110806012353.891757693@goodmis.org
    Link: http://lkml.kernel.org/r/20140206144321.608754481@goodmis.orgSigned-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
    0788aa6a
thread_info.h 8.54 KB