(2013/12/12 3:11), Oleg Nesterov wrote: > On 12/11, Masami Hiramatsu wrote: >> >> (2013/12/11 0:57), Oleg Nesterov wrote: >>> On 12/10, Masami Hiramatsu wrote: >>>> >>>> and isn't it better to increment >>>> miss-hit counter of the uprobe? >>> >>> What do you mean? This is not miss-hit and ->utask == NULL is quite normal. >> >> But it could skip the handler_chain silently. It could confuse users >> why their probe doesn't hit as expected. > > No, we will restart the same (probed) instruction, handle_swbp() > will be called again, get_utask() will be called again.
Hmm, in that case, how would you avoid infinite recursive loop?? Would you repeat it until get_utask() != NULL? > Not to mention that (in practice) if GFP_KERNEL fails the task is > already killed. > >>> For example, on ppc it can be always NULL because ppc likely emulates the >>> probed insn. >> >> Hmm, in that case, should uprobes handlers never be called on ppc with >> this change? > > Why? With this change ppc will have ->utask != NULL even if it doesn't > need it at all. Ah, I see. This changes that. Thank you, -- Masami HIRAMATSU IT Management Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: masami.hiramatsu...@hitachi.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
