2015-05-27 2:17 GMT+02:00 Wu, Feng <feng...@intel.com>: >> Sent: Wednesday, May 27, 2015 2:19 AM >> To: Wu, Feng >> Cc: Valentin Rothberg; Paul Bolle; Andreas Ruprecht; t...@linutronix.de; >> x...@kernel.org; linux-kernel@vger.kernel.org; ru...@rustcorp.com.au; >> mi...@redhat.com >> Subject: unnecessary #ifdefs >> >> Hi Feng Wu, >> >> your commits >> >> f6b3c72c23661e55 ("x86/irq: Define a global vector for VT-d >> Posted-Interrupts") >> 501b32653ebf49114c ("x86/irq: Show statistics information for >> posted-interrupts") >> >> showed up in linux-next today (i.e. next-20150526). >> >> Both commits add "#ifdef CONFIG_HAVE_KVM" blocks to either >> arch/x86/kernel/irq.c or arch/x86/include/asm/irq.h >> >> However, HAVE_KVM is always enabled in x86, since the root option X86 >> always selects HAVE_KVM. >> >> How is the policy here, are these blocks inserted in case the "select >> HAVE_KVM" is removed from X86 someday or did you mean to use >> CONFIG_KVM? >> > > In fact, some of the "#ifdef CONFIG_HAVE_KVM" have been there for a while, > it was introduced for a special IPI for posted-interrupts used for KVM. Now we > need to add other similar IPI for posted-interrupts for KVM, so I just follow > the > existing infrastructure. You can refer to commit " > d78f2664832f8d70e36422af9a10e44276dced48 ", > where "#ifdef CONFIG_HAVE_KVM" was original used. > > Thanks, > Feng
Yes, so i've noticed. However, that doesn't change, that these #ifdefs and the #ifdefs introduced with d78f2664832f8d70e3642 are unnecessary since CONFIG_HAVE_KVM is always enabled in X86. Maybe Yang Zhang can give some insights why they were introduced in the first place? Since both files are beneath arch/x86/ they shouldn't be used in another architecture than X86 and even UML has its own arch/x86/kernel/irq.c and arch/x86/include/asm/irq.h Best Regards, Stefan > >> >> I detected the issue with undertaker-checkpatch [1, 2] running on a >> bot in Erlangen [3] to make daily checks of commits in linux-next for >> #ifdef related defects. >> >> Best Regards, >> Stefan >> >> [1] https://undertaker.cs.fau.de >> [2] http://www.linuxplumbersconf.org/2014/ocw/proposals/1863 >> [3] https://cados.cs.fau.de -- 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/