If I recall correctly, one of the commits that followed this one also added ValidKernelPteLocal and ValidKernelPdeLocal, which are used for PTEs/PDEs that shouldn't be global.
Regards, Alex On Thu, Oct 15, 2015 at 06:55:51PM -0700, Alex Ionescu wrote: > This is wrong, wrong, wrong. > > 1) The feature needs to be enabled on all processors, not just one. There's > a reason for that loop. > > 2) ValidKernelPte/Pde being marked global will make ALL kernel pages > global. This is probably not what you want. > > Best regards, > Alex Ionescu > > On Wed, Oct 14, 2015 at 12:33 PM, <sginsb...@svn.reactos.org> wrote: > > > Author: sginsberg > > Date: Wed Oct 14 19:33:35 2015 > > New Revision: 69528 > > > > URL: http://svn.reactos.org/svn/reactos?rev=69528&view=rev > > Log: > > [NTOS] > > Add super-complicated handling of global pages to KeFlushCurrentTb (pretty > > much the same code which has been in HalpFlushTLB for the past ~6 years). > > This should be all that is required to make this feature work (everything > > else being in place already), and *seems* to work fine but is disabled > > under a switch until tested thoroughly. > > > > Global pages, an important optimization that allows for not flushing the > > whole x86 TLB every time CR3 is changed (typically on context switch to a > > new process, or during process attach/detach), relies on us doing extra > > work whenever we do alter a global page. This is likely where any bugs will > > have to be flushed out! > > > > Fixup Ki386EnableGlobalPage while we are at it -- disable/restore > > interrupts properly, and verify PGE-bit isn't set (nothing should have > > touched it before this routine, which is responsible for initializing it, > > so we shouldn't have to disable it). Fix, but disable, the CPU-sync spin as > > well as there should be no particular reason to do this for PGE-enabling > > during initialization (no other processor will be messing with PTEs at this > > stage, as compared to a call to KeFlushEntireTb). > > > > Everyone, repeat after me: Global pages are awesome! > > > > Modified: > > trunk/reactos/ntoskrnl/include/ntoskrnl.h > > trunk/reactos/ntoskrnl/ke/i386/cpu.c > > trunk/reactos/ntoskrnl/ke/i386/patpge.c > > trunk/reactos/ntoskrnl/mm/ARM3/i386/init.c > > > > Modified: trunk/reactos/ntoskrnl/include/ntoskrnl.h > > URL: > > http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/include/ntoskrnl.h?rev=69528&r1=69527&r2=69528&view=diff > > > > ============================================================================== > > --- trunk/reactos/ntoskrnl/include/ntoskrnl.h [iso-8859-1] (original) > > +++ trunk/reactos/ntoskrnl/include/ntoskrnl.h [iso-8859-1] Wed Oct 14 > > 19:33:35 2015 > > @@ -98,6 +98,14 @@ > > #define ASSERT NT_ASSERT > > #endif > > > > + > > +// > > +// Switch for enabling global page support > > +// > > + > > +//#define _GLOBAL_PAGES_ARE_AWESOME_ > > + > > + > > /* Internal Headers */ > > #include "internal/ntoskrnl.h" > > #include "config.h" > > > > Modified: trunk/reactos/ntoskrnl/ke/i386/cpu.c > > URL: > > http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/ke/i386/cpu.c?rev=69528&r1=69527&r2=69528&view=diff > > > > ============================================================================== > > --- trunk/reactos/ntoskrnl/ke/i386/cpu.c [iso-8859-1] (original) > > +++ trunk/reactos/ntoskrnl/ke/i386/cpu.c [iso-8859-1] Wed Oct 14 > > 19:33:35 2015 > > @@ -878,8 +878,37 @@ > > NTAPI > > KeFlushCurrentTb(VOID) > > { > > + > > +#if !defined(_GLOBAL_PAGES_ARE_AWESOME_) > > + > > /* Flush the TLB by resetting CR3 */ > > __writecr3(__readcr3()); > > + > > +#else > > + > > + /* Check if global pages are enabled */ > > + if (KeFeatureBits & KF_GLOBAL_PAGE) > > + { > > + ULONG Cr4; > > + > > + /* Disable PGE */ > > + Cr4 = __readcr4() & ~CR4_PGE; > > + __writecr4(Cr4); > > + > > + /* Flush everything */ > > + __writecr3(__readcr3()); > > + > > + /* Re-enable PGE */ > > + __writecr4(Cr4 | CR4_PGE); > > + } > > + else > > + { > > + /* No global pages, resetting CR3 is enough */ > > + __writecr3(__readcr3()); > > + } > > + > > +#endif > > + > > } > > > > VOID > > > > Modified: trunk/reactos/ntoskrnl/ke/i386/patpge.c > > URL: > > http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/ke/i386/patpge.c?rev=69528&r1=69527&r2=69528&view=diff > > > > ============================================================================== > > --- trunk/reactos/ntoskrnl/ke/i386/patpge.c [iso-8859-1] (original) > > +++ trunk/reactos/ntoskrnl/ke/i386/patpge.c [iso-8859-1] Wed Oct 14 > > 19:33:35 2015 > > @@ -17,40 +17,41 @@ > > > > /* FUNCTIONS > > *****************************************************************/ > > > > +INIT_SECTION > > ULONG_PTR > > NTAPI > > -INIT_FUNCTION > > Ki386EnableGlobalPage(IN ULONG_PTR Context) > > { > > - PLONG Count = (PLONG)Context; > > - ULONG Cr4, Cr3; > > + //PLONG Count; > > +#if defined(_GLOBAL_PAGES_ARE_AWESOME_) > > + ULONG Cr4; > > +#endif > > + BOOLEAN Enable; > > > > /* Disable interrupts */ > > - _disable(); > > - > > - /* Decrease CPU Count and loop until it's reached 0 */ > > - do {InterlockedDecrement(Count);} while (!*Count); > > - > > - /* Now check if this is the Boot CPU */ > > - if (!KeGetPcr()->Number) > > - { > > - /* It is.FIXME: Patch KeFlushCurrentTb */ > > - } > > - > > - /* Now get CR4 and make sure PGE is masked out */ > > + Enable = KeDisableInterrupts(); > > + > > + /* Spin until other processors are ready */ > > + //Count = (PLONG)Context; > > + //InterlockedDecrement(Count); > > + //while (*Count) YieldProcessor(); > > + > > +#if defined(_GLOBAL_PAGES_ARE_AWESOME_) > > + > > + /* Get CR4 and ensure global pages are disabled */ > > Cr4 = __readcr4(); > > - __writecr4(Cr4 & ~CR4_PGE); > > - > > - /* Flush the TLB */ > > - Cr3 = __readcr3(); > > - __writecr3(Cr3); > > + ASSERT(!(Cr4 & CR4_PGE)); > > + > > + /* Reset CR3 to flush the TLB */ > > + __writecr3(__readcr3()); > > > > /* Now enable PGE */ > > - DPRINT("Global page support detected but not yet taken advantage > > of\n"); > > - //__writecr4(Cr4 | CR4_PGE); > > - > > - /* Restore interrupts */ > > - _enable(); > > + __writecr4(Cr4 | CR4_PGE); > > + > > +#endif > > + > > + /* Restore interrupts and return */ > > + KeRestoreInterrupts(Enable); > > return 0; > > } > > > > > > Modified: trunk/reactos/ntoskrnl/mm/ARM3/i386/init.c > > URL: > > http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/mm/ARM3/i386/init.c?rev=69528&r1=69527&r2=69528&view=diff > > > > ============================================================================== > > --- trunk/reactos/ntoskrnl/mm/ARM3/i386/init.c [iso-8859-1] (original) > > +++ trunk/reactos/ntoskrnl/mm/ARM3/i386/init.c [iso-8859-1] Wed Oct 14 > > 19:33:35 2015 > > @@ -249,15 +249,18 @@ > > PMMPFN Pfn1; > > ULONG Flags; > > > > +#if defined(_GLOBAL_PAGES_ARE_AWESOME_) > > + > > /* Check for global bit */ > > -#if 0 > > if (KeFeatureBits & KF_GLOBAL_PAGE) > > { > > /* Set it on the template PTE and PDE */ > > ValidKernelPte.u.Hard.Global = TRUE; > > ValidKernelPde.u.Hard.Global = TRUE; > > } > > + > > #endif > > + > > /* Now templates are ready */ > > TempPte = ValidKernelPte; > > TempPde = ValidKernelPde; > > > > > > > _______________________________________________ > Ros-dev mailing list > Ros-dev@reactos.org > http://www.reactos.org/mailman/listinfo/ros-dev -- Alexander Andrejevic <thefl...@sdf.lonestar.org> SDF Public Access UNIX System - http://sdf.lonestar.org _______________________________________________ Ros-dev mailing list Ros-dev@reactos.org http://www.reactos.org/mailman/listinfo/ros-dev
