Oleg Nesterov 3247343118 uprobes: Add uprobe_task->dup_xol_work/dup_xol_addr ... uprobe_task->vaddr is a bit strange. The generic code uses it only to pass the additional argument to arch_uprobe_pre_xol(), and since it is always equal to instruction_pointer() this looks even more strange. And both utask->vaddr and and utask->autask have the same scope, they only have the meaning when the task executes the probed insn out-of-line, so it is safe to reuse both in UTASK_RUNNING state. This all means that logically ->vaddr belongs to arch_uprobe_task and we should probably move it there, arch_uprobe_pre_xol() can record instruction_pointer() itself. OTOH, it is also used by uprobe_copy_process() and dup_xol_work() for another purpose, this doesn't look clean and doesn't allow to move this member into arch_uprobe_task. This patch adds the union with 2 anonymous structs into uprobe_task. The first struct is autask + vaddr, this way we "almost" move vaddr into autask. The second struct has 2 new members for uprobe_copy_process() paths: ->dup_xol_addr which can be used instead ->vaddr, and ->dup_xol_work which can be used to avoid kmalloc() and simplify the code. Note that this union will likely have another member(s), we need something like "private_data_for_handlers" so that the tracing handlers could use it to communicate with call_fetch() methods. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>		2013-11-20 16:30:57 +01:00
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callchain.c
core.c	perf: Factor out strncpy() in perf_event_mmap_event()	2013-11-06 12:34:28 +01:00
hw_breakpoint.c
internal.h
Makefile
ring_buffer.c
uprobes.c	uprobes: Add uprobe_task->dup_xol_work/dup_xol_addr	2013-11-20 16:30:57 +01:00