• O
    uprobes: Kill uprobes_srcu/uprobe_srcu_id · 778b032d
    Oleg Nesterov 提交于
    Kill the no longer needed uprobes_srcu/uprobe_srcu_id code.
    
    It doesn't really work anyway. synchronize_srcu() can only
    synchronize with the code "inside" the
    srcu_read_lock/srcu_read_unlock section, while
    uprobe_pre_sstep_notifier() does srcu_read_lock() _after_ we
    already hit the breakpoint.
    
    I guess this probably works "in practice". synchronize_srcu() is
    slow and it implies synchronize_sched(), and the probed task
    enters the non- preemptible section at the start of exception
    handler. Still this is not right at least in theory, and
    task->uprobe_srcu_id blows task_struct.
    Signed-off-by: NOleg Nesterov <oleg@redhat.com>
    Acked-by: NSrikar Dronamraju <srikar@linux.vnet.ibm.com>
    Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
    Cc: Anton Arapov <anton@redhat.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Link: http://lkml.kernel.org/r/20120529193008.GG8057@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
    778b032d
sched.h 82.0 KB