Author: markj Date: Tue Jan 10 21:52:48 2017 New Revision: 311902 URL: https://svnweb.freebsd.org/changeset/base/311902
Log: Coalesce TLB shootdowns of global PTEs in pmap_advise() on x86. We would previously invalidate such entries individually, resulting in more IPIs than necessary. Reviewed by: alc, kib MFC after: 3 weeks Differential Revision: https://reviews.freebsd.org/D9094 Modified: head/sys/amd64/amd64/pmap.c head/sys/i386/i386/pmap.c Modified: head/sys/amd64/amd64/pmap.c ============================================================================== --- head/sys/amd64/amd64/pmap.c Tue Jan 10 21:41:28 2017 (r311901) +++ head/sys/amd64/amd64/pmap.c Tue Jan 10 21:52:48 2017 (r311902) @@ -6010,7 +6010,7 @@ pmap_advise(pmap_t pmap, vm_offset_t sva pdp_entry_t *pdpe; pd_entry_t oldpde, *pde; pt_entry_t *pte, PG_A, PG_G, PG_M, PG_RW, PG_V; - vm_offset_t va_next; + vm_offset_t va, va_next; vm_page_t m; boolean_t anychanged; @@ -6090,11 +6090,11 @@ pmap_advise(pmap_t pmap, vm_offset_t sva } if (va_next > eva) va_next = eva; + va = va_next; for (pte = pmap_pde_to_pte(pde, sva); sva != va_next; pte++, sva += PAGE_SIZE) { - if ((*pte & (PG_MANAGED | PG_V)) != (PG_MANAGED | - PG_V)) - continue; + if ((*pte & (PG_MANAGED | PG_V)) != (PG_MANAGED | PG_V)) + goto maybe_invlrng; else if ((*pte & (PG_M | PG_RW)) == (PG_M | PG_RW)) { if (advice == MADV_DONTNEED) { /* @@ -6109,12 +6109,22 @@ pmap_advise(pmap_t pmap, vm_offset_t sva } else if ((*pte & PG_A) != 0) atomic_clear_long(pte, PG_A); else - continue; - if ((*pte & PG_G) != 0) - pmap_invalidate_page(pmap, sva); - else + goto maybe_invlrng; + + if ((*pte & PG_G) != 0) { + if (va == va_next) + va = sva; + } else anychanged = TRUE; + continue; +maybe_invlrng: + if (va != va_next) { + pmap_invalidate_range(pmap, va, sva); + va = va_next; + } } + if (va != va_next) + pmap_invalidate_range(pmap, va, sva); } if (anychanged) pmap_invalidate_all(pmap); Modified: head/sys/i386/i386/pmap.c ============================================================================== --- head/sys/i386/i386/pmap.c Tue Jan 10 21:41:28 2017 (r311901) +++ head/sys/i386/i386/pmap.c Tue Jan 10 21:52:48 2017 (r311902) @@ -4905,7 +4905,7 @@ pmap_advise(pmap_t pmap, vm_offset_t sva { pd_entry_t oldpde, *pde; pt_entry_t *pte; - vm_offset_t pdnxt; + vm_offset_t va, pdnxt; vm_page_t m; boolean_t anychanged, pv_lists_locked; @@ -4966,11 +4966,11 @@ resume: } if (pdnxt > eva) pdnxt = eva; + va = pdnxt; for (pte = pmap_pte_quick(pmap, sva); sva != pdnxt; pte++, sva += PAGE_SIZE) { - if ((*pte & (PG_MANAGED | PG_V)) != (PG_MANAGED | - PG_V)) - continue; + if ((*pte & (PG_MANAGED | PG_V)) != (PG_MANAGED | PG_V)) + goto maybe_invlrng; else if ((*pte & (PG_M | PG_RW)) == (PG_M | PG_RW)) { if (advice == MADV_DONTNEED) { /* @@ -4985,12 +4985,21 @@ resume: } else if ((*pte & PG_A) != 0) atomic_clear_int((u_int *)pte, PG_A); else - continue; - if ((*pte & PG_G) != 0) - pmap_invalidate_page(pmap, sva); - else + goto maybe_invlrng; + if ((*pte & PG_G) != 0) { + if (va == pdnxt) + va = sva; + } else anychanged = TRUE; + continue; +maybe_invlrng: + if (va != pdnxt) { + pmap_invalidate_range(pmap, va, sva); + va = pdnxt; + } } + if (va != pdnxt) + pmap_invalidate_range(pmap, va, sva); } if (anychanged) pmap_invalidate_all(pmap); _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
