Messages in this thread | | | Subject | Re: [PATCH 8/8] membarrier: Rewrite sync_core_before_usermode() and improve documentation | From | Christophe Leroy <> | Date | Fri, 18 Jun 2021 17:27:21 +0200 |
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Le 16/06/2021 à 20:52, Andy Lutomirski a écrit : > On 6/15/21 9:45 PM, Nicholas Piggin wrote: >> Excerpts from Andy Lutomirski's message of June 16, 2021 1:21 pm: >>> The old sync_core_before_usermode() comments suggested that a non-icache-syncing >>> return-to-usermode instruction is x86-specific and that all other >>> architectures automatically notice cross-modified code on return to >>> userspace. > >>> +/* >>> + * XXX: can a powerpc person put an appropriate comment here? >>> + */ >>> +static inline void membarrier_sync_core_before_usermode(void) >>> +{ >>> +} >>> + >>> +#endif /* _ASM_POWERPC_SYNC_CORE_H */ >> >> powerpc's can just go in asm/membarrier.h > > $ ls arch/powerpc/include/asm/membarrier.h > ls: cannot access 'arch/powerpc/include/asm/membarrier.h': No such file > or directory
https://github.com/torvalds/linux/blob/master/arch/powerpc/include/asm/membarrier.h
Was added by https://github.com/torvalds/linux/commit/3ccfebedd8cf54e291c809c838d8ad5cc00f5688
> > >> >> /* >> * The RFI family of instructions are context synchronising, and >> * that is how we return to userspace, so nothing is required here. >> */ > > Thanks! >
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