Re: [Xen-devel] [PATCH v9 01/28] linkage: Introduce new macros for assembler symbols
On Fri, Oct 11, 2019 at 1:53 PM Jiri Slaby wrote: > > Introduce new C macros for annotations of functions and data in > assembly. There is a long-standing mess in macros like ENTRY, END, > ENDPROC and similar. They are used in different manners and sometimes > incorrectly. > > So introduce macros with clear use to annotate assembly as follows: > > a) Support macros for the ones below >SYM_T_FUNC -- type used by assembler to mark functions >SYM_T_OBJECT -- type used by assembler to mark data >SYM_T_NONE -- type used by assembler to mark entries of unknown type > >They are defined as STT_FUNC, STT_OBJECT, and STT_NOTYPE >respectively. According to the gas manual, this is the most portable >way. I am not sure about other assemblers, so this can be switched >back to %function and %object if this turns into a problem. >Architectures can also override them by something like ", @function" >if they need. > >SYM_A_ALIGN, SYM_A_NONE -- align the symbol? >SYM_L_GLOBAL, SYM_L_WEAK, SYM_L_LOCAL -- linkage of symbols > > b) Mostly internal annotations, used by the ones below >SYM_ENTRY -- use only if you have to (for non-paired symbols) >SYM_START -- use only if you have to (for paired symbols) >SYM_END -- use only if you have to (for paired symbols) > > c) Annotations for code >SYM_INNER_LABEL_ALIGN -- only for labels in the middle of code >SYM_INNER_LABEL -- only for labels in the middle of code > >SYM_FUNC_START_LOCAL_ALIAS -- use where there are two local names for > one function >SYM_FUNC_START_ALIAS -- use where there are two global names for one > function >SYM_FUNC_END_ALIAS -- the end of LOCAL_ALIASed or ALIASed function > >SYM_FUNC_START -- use for global functions >SYM_FUNC_START_NOALIGN -- use for global functions, w/o alignment >SYM_FUNC_START_LOCAL -- use for local functions >SYM_FUNC_START_LOCAL_NOALIGN -- use for local functions, w/o > alignment >SYM_FUNC_START_WEAK -- use for weak functions >SYM_FUNC_START_WEAK_NOALIGN -- use for weak functions, w/o alignment >SYM_FUNC_END -- the end of SYM_FUNC_START_LOCAL, SYM_FUNC_START, > SYM_FUNC_START_WEAK, ... > >For functions with special (non-C) calling conventions: >SYM_CODE_START -- use for non-C (special) functions >SYM_CODE_START_NOALIGN -- use for non-C (special) functions, w/o > alignment >SYM_CODE_START_LOCAL -- use for local non-C (special) functions >SYM_CODE_START_LOCAL_NOALIGN -- use for local non-C (special) > functions, w/o alignment >SYM_CODE_END -- the end of SYM_CODE_START_LOCAL or SYM_CODE_START > > d) For data >SYM_DATA_START -- global data symbol >SYM_DATA_START_LOCAL -- local data symbol >SYM_DATA_END -- the end of the SYM_DATA_START symbol >SYM_DATA_END_LABEL -- the labeled end of SYM_DATA_START symbol >SYM_DATA -- start+end wrapper around simple global data >SYM_DATA_LOCAL -- start+end wrapper around simple local data > > == > > The macros allow to pair starts and ends of functions and mark functions > correctly in the output ELF objects. > > All users of the old macros in x86 are converted to use these in further > patches. > > Signed-off-by: Jiri Slaby > Cc: Andrew Morton > Cc: Boris Ostrovsky > Cc: h...@zytor.com > Cc: Ingo Molnar > Cc: jpoim...@redhat.com > Cc: Juergen Gross > Cc: Len Brown > Cc: Linus Torvalds > Cc: linux-ker...@vger.kernel.org > Cc: linux...@vger.kernel.org > Cc: Borislav Petkov > Cc: mi...@redhat.com > Cc: Pavel Machek > Cc: Peter Zijlstra > Cc: "Rafael J. Wysocki" > Cc: Thomas Gleixner > Cc: xen-devel@lists.xenproject.org > Cc: x...@kernel.org Acked-by: Rafael J. Wysocki for all the changes in the series affecting the power management code maintained by me. Thanks! > --- > > Notes: > [v2] > * use SYM_ prefix and sane names > * add SYM_START and SYM_END and parametrize all the macros > > [v3] > * add SYM_DATA, SYM_DATA_LOCAL, and SYM_DATA_END_LABEL > > [v4] > * add _NOALIGN versions of some macros > * add _CODE_ derivates of _FUNC_ macros > > [v5] > * drop "SIMPLE" from data annotations > * switch NOALIGN and ALIGN variants of inner labels > * s/visibility/linkage/; s@SYM_V_@SYM_L_@ > * add Documentation > > [v6] > * fixed typos found by Randy Dunlap > * remove doubled INNER_LABEL macros, one pair was unused > > [v8] > * use lkml.kernel.org for links > * link the docs from index.rst (by Boris) > * fixed typos on the docs > > [v9] > * updated the docs as requested by Boris > > Documentation/asm-annotations.rst | 216 ++ > Documentation/index.rst | 8 + > arch/x86/include/asm/linkage.h| 10 +- > include/linux/linkage.h | 245 +- > 4 files changed, 468 insertions(+), 11 deletions(-) > create mode 100644 Documentation/asm-annotation
[Xen-devel] [PATCH v9 01/28] linkage: Introduce new macros for assembler symbols
Introduce new C macros for annotations of functions and data in assembly. There is a long-standing mess in macros like ENTRY, END, ENDPROC and similar. They are used in different manners and sometimes incorrectly. So introduce macros with clear use to annotate assembly as follows: a) Support macros for the ones below SYM_T_FUNC -- type used by assembler to mark functions SYM_T_OBJECT -- type used by assembler to mark data SYM_T_NONE -- type used by assembler to mark entries of unknown type They are defined as STT_FUNC, STT_OBJECT, and STT_NOTYPE respectively. According to the gas manual, this is the most portable way. I am not sure about other assemblers, so this can be switched back to %function and %object if this turns into a problem. Architectures can also override them by something like ", @function" if they need. SYM_A_ALIGN, SYM_A_NONE -- align the symbol? SYM_L_GLOBAL, SYM_L_WEAK, SYM_L_LOCAL -- linkage of symbols b) Mostly internal annotations, used by the ones below SYM_ENTRY -- use only if you have to (for non-paired symbols) SYM_START -- use only if you have to (for paired symbols) SYM_END -- use only if you have to (for paired symbols) c) Annotations for code SYM_INNER_LABEL_ALIGN -- only for labels in the middle of code SYM_INNER_LABEL -- only for labels in the middle of code SYM_FUNC_START_LOCAL_ALIAS -- use where there are two local names for one function SYM_FUNC_START_ALIAS -- use where there are two global names for one function SYM_FUNC_END_ALIAS -- the end of LOCAL_ALIASed or ALIASed function SYM_FUNC_START -- use for global functions SYM_FUNC_START_NOALIGN -- use for global functions, w/o alignment SYM_FUNC_START_LOCAL -- use for local functions SYM_FUNC_START_LOCAL_NOALIGN -- use for local functions, w/o alignment SYM_FUNC_START_WEAK -- use for weak functions SYM_FUNC_START_WEAK_NOALIGN -- use for weak functions, w/o alignment SYM_FUNC_END -- the end of SYM_FUNC_START_LOCAL, SYM_FUNC_START, SYM_FUNC_START_WEAK, ... For functions with special (non-C) calling conventions: SYM_CODE_START -- use for non-C (special) functions SYM_CODE_START_NOALIGN -- use for non-C (special) functions, w/o alignment SYM_CODE_START_LOCAL -- use for local non-C (special) functions SYM_CODE_START_LOCAL_NOALIGN -- use for local non-C (special) functions, w/o alignment SYM_CODE_END -- the end of SYM_CODE_START_LOCAL or SYM_CODE_START d) For data SYM_DATA_START -- global data symbol SYM_DATA_START_LOCAL -- local data symbol SYM_DATA_END -- the end of the SYM_DATA_START symbol SYM_DATA_END_LABEL -- the labeled end of SYM_DATA_START symbol SYM_DATA -- start+end wrapper around simple global data SYM_DATA_LOCAL -- start+end wrapper around simple local data == The macros allow to pair starts and ends of functions and mark functions correctly in the output ELF objects. All users of the old macros in x86 are converted to use these in further patches. Signed-off-by: Jiri Slaby Cc: Andrew Morton Cc: Boris Ostrovsky Cc: h...@zytor.com Cc: Ingo Molnar Cc: jpoim...@redhat.com Cc: Juergen Gross Cc: Len Brown Cc: Linus Torvalds Cc: linux-ker...@vger.kernel.org Cc: linux...@vger.kernel.org Cc: Borislav Petkov Cc: mi...@redhat.com Cc: Pavel Machek Cc: Peter Zijlstra Cc: "Rafael J. Wysocki" Cc: Thomas Gleixner Cc: xen-devel@lists.xenproject.org Cc: x...@kernel.org --- Notes: [v2] * use SYM_ prefix and sane names * add SYM_START and SYM_END and parametrize all the macros [v3] * add SYM_DATA, SYM_DATA_LOCAL, and SYM_DATA_END_LABEL [v4] * add _NOALIGN versions of some macros * add _CODE_ derivates of _FUNC_ macros [v5] * drop "SIMPLE" from data annotations * switch NOALIGN and ALIGN variants of inner labels * s/visibility/linkage/; s@SYM_V_@SYM_L_@ * add Documentation [v6] * fixed typos found by Randy Dunlap * remove doubled INNER_LABEL macros, one pair was unused [v8] * use lkml.kernel.org for links * link the docs from index.rst (by Boris) * fixed typos on the docs [v9] * updated the docs as requested by Boris Documentation/asm-annotations.rst | 216 ++ Documentation/index.rst | 8 + arch/x86/include/asm/linkage.h| 10 +- include/linux/linkage.h | 245 +- 4 files changed, 468 insertions(+), 11 deletions(-) create mode 100644 Documentation/asm-annotations.rst diff --git a/Documentation/asm-annotations.rst b/Documentation/asm-annotations.rst new file mode 100644 index ..29ccd6e61fe5 --- /dev/null +++ b/Documentation/asm-annotations.rst @@ -0,0 +1,216 @@ +Assembler Annotations += + +Copyright (c) 2017-2019 Jiri Slaby + +This document describes the new macros for annotation of data and code in +assembly. In pa
