Date: Wed, 1 Jul 2015 17:27:44 +0000 (UTC) From: Andrew Turner <andrew@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r285014 - head/sys/arm64/arm64 Message-ID: <201507011727.t61HRiKB047198@svn.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: andrew Date: Wed Jul 1 17:27:44 2015 New Revision: 285014 URL: https://svnweb.freebsd.org/changeset/base/285014 Log: Fix the logic for when to restore the VFP registers. It should restore them when a different thread last used them, or when the thread was last run on a different cpu. Obtained from: ABT Systems Ltd Sponsored by: The FreeBSD Foundation Modified: head/sys/arm64/arm64/vfp.c Modified: head/sys/arm64/arm64/vfp.c ============================================================================== --- head/sys/arm64/arm64/vfp.c Wed Jul 1 17:19:51 2015 (r285013) +++ head/sys/arm64/arm64/vfp.c Wed Jul 1 17:27:44 2015 (r285014) @@ -95,6 +95,9 @@ vfp_save_state(struct thread *td) */ cpacr = READ_SPECIALREG(cpacr_el1); if ((cpacr & CPACR_FPEN_MASK) == CPACR_FPEN_TRAP_NONE) { + KASSERT(PCPU_GET(fpcurthread) == td, + ("Storing an invalid VFP state")); + vfp_state = td->td_pcb->pcb_vfp; __asm __volatile( "mrs %0, fpcr \n" @@ -142,7 +145,12 @@ vfp_restore_state(void) vfp_enable(); - if (PCPU_GET(fpcurthread) != curthread && cpu != curpcb->pcb_vfpcpu) { + /* + * If the previous thread on this cpu to use the VFP was not the + * current threas, or the current thread last used it on a different + * cpu we need to restore the old state. + */ + if (PCPU_GET(fpcurthread) != curthread || cpu != curpcb->pcb_vfpcpu) { vfp_state = curthread->td_pcb->pcb_vfp; fpcr = curthread->td_pcb->pcb_fpcr;
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201507011727.t61HRiKB047198>