Messages in this thread | | | Date | Fri, 8 Mar 2019 11:09:23 +1100 | From | David Gibson <> | Subject | Re: [PATCH] powerpc/mm: move warning from resize_hpt_for_hotplug() |
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On Thu, Mar 07, 2019 at 03:50:50PM +0100, Laurent Vivier wrote: > resize_hpt_for_hotplug() reports a warning when it cannot > resize the hash page table ("Unable to resize hash page > table to target order") but in some cases it's not a problem > and can make user thinks something has not worked properly. > > This patch moves the warning to arch_remove_memory() to > only report the problem when it is needed. > > Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Looks ok, but apart from the H_PTEG_FULL case this does allow for some error paths that previously warned to pass without error, which I don't think is wise.
Specifically that will happen the prepare hcall returns H_PARAMETER or H_RESOURCE. Thse will result in -EINVAL or -EPERM from pseries_lpar_resize_hpt() which previously would have tripped the warning in resize_hpt_for_hotplug() but now will be silently ignored.
> --- > arch/powerpc/include/asm/sparsemem.h | 4 ++-- > arch/powerpc/mm/hash_utils_64.c | 17 ++++++----------- > arch/powerpc/mm/mem.c | 3 ++- > arch/powerpc/platforms/pseries/lpar.c | 1 - > 4 files changed, 10 insertions(+), 15 deletions(-) > > diff --git a/arch/powerpc/include/asm/sparsemem.h b/arch/powerpc/include/asm/sparsemem.h > index 68da49320592..3192d454a733 100644 > --- a/arch/powerpc/include/asm/sparsemem.h > +++ b/arch/powerpc/include/asm/sparsemem.h > @@ -17,9 +17,9 @@ extern int create_section_mapping(unsigned long start, unsigned long end, int ni > extern int remove_section_mapping(unsigned long start, unsigned long end); > > #ifdef CONFIG_PPC_BOOK3S_64 > -extern void resize_hpt_for_hotplug(unsigned long new_mem_size); > +extern int resize_hpt_for_hotplug(unsigned long new_mem_size); > #else > -static inline void resize_hpt_for_hotplug(unsigned long new_mem_size) { } > +static inline int resize_hpt_for_hotplug(unsigned long new_mem_size) { return 0; } > #endif > > #ifdef CONFIG_NUMA > diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c > index 0cc7fbc3bd1c..40bb2a8326bb 100644 > --- a/arch/powerpc/mm/hash_utils_64.c > +++ b/arch/powerpc/mm/hash_utils_64.c > @@ -755,12 +755,12 @@ static unsigned long __init htab_get_table_size(void) > } > > #ifdef CONFIG_MEMORY_HOTPLUG > -void resize_hpt_for_hotplug(unsigned long new_mem_size) > +int resize_hpt_for_hotplug(unsigned long new_mem_size) > { > unsigned target_hpt_shift; > > if (!mmu_hash_ops.resize_hpt) > - return; > + return 0; > > target_hpt_shift = htab_shift_for_mem_size(new_mem_size); > > @@ -773,15 +773,10 @@ void resize_hpt_for_hotplug(unsigned long new_mem_size) > * current shift > */ > if ((target_hpt_shift > ppc64_pft_size) > - || (target_hpt_shift < (ppc64_pft_size - 1))) { > - int rc; > - > - rc = mmu_hash_ops.resize_hpt(target_hpt_shift); > - if (rc && (rc != -ENODEV)) > - printk(KERN_WARNING > - "Unable to resize hash page table to target order %d: %d\n", > - target_hpt_shift, rc); > - } > + || (target_hpt_shift < (ppc64_pft_size - 1))) > + return mmu_hash_ops.resize_hpt(target_hpt_shift); > + > + return 0; > } > > int hash__create_section_mapping(unsigned long start, unsigned long end, int nid) > diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c > index 33cc6f676fa6..0d40d970cf4a 100644 > --- a/arch/powerpc/mm/mem.c > +++ b/arch/powerpc/mm/mem.c > @@ -169,7 +169,8 @@ int __meminit arch_remove_memory(int nid, u64 start, u64 size, > */ > vm_unmap_aliases(); > > - resize_hpt_for_hotplug(memblock_phys_mem_size()); > + if (resize_hpt_for_hotplug(memblock_phys_mem_size()) == -ENOSPC) > + pr_warn("Hash collision while resizing HPT\n"); > > return ret; > } > diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c > index f2a9f0adc2d3..b407034a80ba 100644 > --- a/arch/powerpc/platforms/pseries/lpar.c > +++ b/arch/powerpc/platforms/pseries/lpar.c > @@ -918,7 +918,6 @@ static int pseries_lpar_resize_hpt(unsigned long shift) > if (rc != 0) { > switch (state.commit_rc) { > case H_PTEG_FULL: > - pr_warn("Hash collision while resizing HPT\n"); > return -ENOSPC; > > default:
-- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson [unhandled content-type:application/pgp-signature] | |