On Wed, Sep 13, 2023 at 10:24 AM Lad, Prabhakar
<[email protected]> wrote:
>
> Hi Alexandre,
>
> On Wed, Sep 13, 2023 at 9:04 AM Alexandre Ghiti <[email protected]> wrote:
> >
> > @Lad, Prabhakar Any chance you give a try to this new patchset? So
> > that we make sure Samuel found your issue :)
> >
> I have given the patches a try and not seen the module load failures
> as seen previously. I have some rigorous tests which test the complete
> platform. I'm just waiting for it to complete before I give Tested by.
>
Awesome, thanks for the update! Well done @Samuel Holland
> Cheers,
> Prabhakar
>
> > On Mon, Sep 11, 2023 at 3:16 PM Alexandre Ghiti <[email protected]> wrote:
> > >
> > > This function used to simply flush the whole tlb of all harts, be more
> > > subtile and try to only flush the range.
> > >
> > > The problem is that we can only use PAGE_SIZE as stride since we don't know
> > > the size of the underlying mapping and then this function will be improved
> > > only if the size of the region to flush is < threshold * PAGE_SIZE.
> > >
> > > Signed-off-by: Alexandre Ghiti <[email protected]>
> > > Reviewed-by: Andrew Jones <[email protected]>
> > > ---
> > > arch/riscv/include/asm/tlbflush.h | 11 ++++++-----
> > > arch/riscv/mm/tlbflush.c | 33 ++++++++++++++++++++++---------
> > > 2 files changed, 30 insertions(+), 14 deletions(-)
> > >
> > > diff --git a/arch/riscv/include/asm/tlbflush.h b/arch/riscv/include/asm/tlbflush.h
> > > index 170a49c531c6..8f3418c5f172 100644
> > > --- a/arch/riscv/include/asm/tlbflush.h
> > > +++ b/arch/riscv/include/asm/tlbflush.h
> > > @@ -40,6 +40,7 @@ void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
> > > void flush_tlb_page(struct vm_area_struct *vma, unsigned long addr);
> > > void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
> > > unsigned long end);
> > > +void flush_tlb_kernel_range(unsigned long start, unsigned long end);
> > > #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > > #define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
> > > void flush_pmd_tlb_range(struct vm_area_struct *vma, unsigned long start,
> > > @@ -56,15 +57,15 @@ static inline void flush_tlb_range(struct vm_area_struct *vma,
> > > local_flush_tlb_all();
> > > }
> > >
> > > -#define flush_tlb_mm(mm) flush_tlb_all()
> > > -#define flush_tlb_mm_range(mm, start, end, page_size) flush_tlb_all()
> > > -#endif /* !CONFIG_SMP || !CONFIG_MMU */
> > > -
> > > /* Flush a range of kernel pages */
> > > static inline void flush_tlb_kernel_range(unsigned long start,
> > > unsigned long end)
> > > {
> > > - flush_tlb_all();
> > > + local_flush_tlb_all();
> > > }
> > >
> > > +#define flush_tlb_mm(mm) flush_tlb_all()
> > > +#define flush_tlb_mm_range(mm, start, end, page_size) flush_tlb_all()
> > > +#endif /* !CONFIG_SMP || !CONFIG_MMU */
> > > +
> > > #endif /* _ASM_RISCV_TLBFLUSH_H */
> > > diff --git a/arch/riscv/mm/tlbflush.c b/arch/riscv/mm/tlbflush.c
> > > index 2c1136d73411..28cd8539b575 100644
> > > --- a/arch/riscv/mm/tlbflush.c
> > > +++ b/arch/riscv/mm/tlbflush.c
> > > @@ -97,19 +97,27 @@ static void __flush_tlb_range(struct mm_struct *mm, unsigned long start,
> > > unsigned long size, unsigned long stride)
> > > {
> > > struct flush_tlb_range_data ftd;
> > > - struct cpumask *cmask = mm_cpumask(mm);
> > > + struct cpumask *cmask, full_cmask;
> > > unsigned long asid = FLUSH_TLB_NO_ASID;
> > > - unsigned int cpuid;
> > > bool broadcast;
> > >
> > > - if (cpumask_empty(cmask))
> > > - return;
> > > + if (mm) {
> > > + unsigned int cpuid;
> > > +
> > > + cmask = mm_cpumask(mm);
> > > + if (cpumask_empty(cmask))
> > > + return;
> > >
> > > - cpuid = get_cpu();
> > > - /* check if the tlbflush needs to be sent to other CPUs */
> > > - broadcast = cpumask_any_but(cmask, cpuid) < nr_cpu_ids;
> > > + cpuid = get_cpu();
> > > + /* check if the tlbflush needs to be sent to other CPUs */
> > > + broadcast = cpumask_any_but(cmask, cpuid) < nr_cpu_ids;
> > > + } else {
> > > + cpumask_setall(&full_cmask);
> > > + cmask = &full_cmask;
> > > + broadcast = true;
> > > + }
> > >
> > > - if (static_branch_unlikely(&use_asid_allocator))
> > > + if (static_branch_unlikely(&use_asid_allocator) && mm)
> > > asid = atomic_long_read(&mm->context.id) & asid_mask;
> > >
> > > if (broadcast) {
> > > @@ -128,7 +136,8 @@ static void __flush_tlb_range(struct mm_struct *mm, unsigned long start,
> > > local_flush_tlb_range_asid(start, size, stride, asid);
> > > }
> > >
> > > - put_cpu();
> > > + if (mm)
> > > + put_cpu();
> > > }
> > >
> > > void flush_tlb_mm(struct mm_struct *mm)
> > > @@ -189,6 +198,12 @@ void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
> > >
> > > __flush_tlb_range(vma->vm_mm, start, end - start, stride_size);
> > > }
> > > +
> > > +void flush_tlb_kernel_range(unsigned long start, unsigned long end)
> > > +{
> > > + __flush_tlb_range(NULL, start, end - start, PAGE_SIZE);
> > > +}
> > > +
> > > #ifdef CONFIG_TRANSPARENT_HUGEPAGE
> > > void flush_pmd_tlb_range(struct vm_area_struct *vma, unsigned long start,
> > > unsigned long end)
> > > --
> > > 2.39.2
> > >