Date: Tue, 19 Sep 2017 09:35:08 +0000 (UTC) From: Andriy Gapon <avg@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Subject: svn commit: r323760 - stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs Message-ID: <201709190935.v8J9Z87t064493@repo.freebsd.org>
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Author: avg Date: Tue Sep 19 09:35:07 2017 New Revision: 323760 URL: https://svnweb.freebsd.org/changeset/base/323760 Log: MFC r323435: MFV r323111: 8569 problem with inline functions in abd.h illumos/illumos-gate@37e84ab74e939caf52150fc3352081786ecc0c29 https://github.com/illumos/illumos-gate/commit/37e84ab74e939caf52150fc3352081786ecc0c29 https://www.illumos.org/issues/8569 C [C99] has peculiar rules for inline functions that are different from the C++ rules. Unlike C++ where inline is "fire and forget", in C a programmer must pay attention to the function's storage class / visibility. The main problem is with the case where a compiler decides to not inline a call to the function declared as inline. Some relevant links: - http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka15831.html - http://www.drdobbs.com/the-new-c-inline-functions/184401540 The summary is that either the inline functions should be declared 'static inline' or one of the compilation units (.c files) must provide a callable externally visible function definition. In the former case, the compiler would automatically create a local non-inlined function instance in every compilation unit where it's needed. In the latter case the single external definition is used to satisfy any non-inlined calls in all compilation units. As things stand right now, we can get an undefined reference error under certain combinations of compilers and compiler options. For example, this is what I get on FreeBSD when compiling with clang 4.0.0 and -O1: In function `abd_free': /usr/src/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/abd.c:385: undefined reference to `abd_is_linear' Reviewed by: Matt Ahrens <mahrens@delphix.com> Approved by: Robert Mustacchi <rm@joyent.com> Author: Andriy Gapon <avg@FreeBSD.org> Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/abd.c Directory Properties: stable/11/ (props changed) Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/abd.c ============================================================================== --- stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/abd.c Tue Sep 19 09:26:13 2017 (r323759) +++ stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/abd.c Tue Sep 19 09:35:07 2017 (r323760) @@ -157,6 +157,13 @@ extern vmem_t *zio_alloc_arena; kmem_cache_t *abd_chunk_cache; static kstat_t *abd_ksp; +extern inline boolean_t abd_is_linear(abd_t *abd); +extern inline void abd_copy(abd_t *dabd, abd_t *sabd, size_t size); +extern inline void abd_copy_from_buf(abd_t *abd, const void *buf, size_t size); +extern inline void abd_copy_to_buf(void* buf, abd_t *abd, size_t size); +extern inline int abd_cmp_buf(abd_t *abd, const void *buf, size_t size); +extern inline void abd_zero(abd_t *abd, size_t size); + static void * abd_alloc_chunk() {
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