| Message ID | 20190114125903.24845-8-david@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mm: PG_reserved cleanups and documentation | expand |
Hi David, On Mon, Jan 14, 2019 at 6:30 PM David Hildenbrand <david@redhat.com> wrote: > > The crashkernel is reserved via memblock_reserve(). memblock_free_all() > will call free_low_memory_core_early(), which will go over all reserved > memblocks, marking the pages as PG_reserved. > > So manually marking pages as PG_reserved is not necessary, they are > already in the desired state (otherwise they would have been handed over > to the buddy as free pages and bad things would happen). > > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Will Deacon <will.deacon@arm.com> > Cc: James Morse <james.morse@arm.com> > Cc: Bhupesh Sharma <bhsharma@redhat.com> > Cc: David Hildenbrand <david@redhat.com> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: Dave Kleikamp <dave.kleikamp@oracle.com> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> > Cc: Michal Hocko <mhocko@suse.com> > Cc: Florian Fainelli <f.fainelli@gmail.com> > Cc: Stefan Agner <stefan@agner.ch> > Cc: Laura Abbott <labbott@redhat.com> > Cc: Greg Hackmann <ghackmann@android.com> > Cc: Johannes Weiner <hannes@cmpxchg.org> > Cc: Kristina Martsenko <kristina.martsenko@arm.com> > Cc: CHANDAN VN <chandan.vn@samsung.com> > Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> > Cc: Logan Gunthorpe <logang@deltatee.com> > Reviewed-by: Matthias Brugger <mbrugger@suse.com> > Signed-off-by: David Hildenbrand <david@redhat.com> > --- > arch/arm64/kernel/machine_kexec.c | 2 +- > arch/arm64/mm/init.c | 27 --------------------------- > 2 files changed, 1 insertion(+), 28 deletions(-) > > diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c > index 6f0587b5e941..66b5d697d943 100644 > --- a/arch/arm64/kernel/machine_kexec.c > +++ b/arch/arm64/kernel/machine_kexec.c > @@ -321,7 +321,7 @@ void crash_post_resume(void) > * but does not hold any data of loaded kernel image. > * > * Note that all the pages in crash dump kernel memory have been initially > - * marked as Reserved in kexec_reserve_crashkres_pages(). > + * marked as Reserved as memory was allocated via memblock_reserve(). > * > * In hibernation, the pages which are Reserved and yet "nosave" are excluded > * from the hibernation iamge. crash_is_nosave() does thich check for crash > diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c > index 7205a9085b4d..c38976b70069 100644 > --- a/arch/arm64/mm/init.c > +++ b/arch/arm64/mm/init.c > @@ -118,35 +118,10 @@ static void __init reserve_crashkernel(void) > crashk_res.start = crash_base; > crashk_res.end = crash_base + crash_size - 1; > } > - > -static void __init kexec_reserve_crashkres_pages(void) > -{ > -#ifdef CONFIG_HIBERNATION > - phys_addr_t addr; > - struct page *page; > - > - if (!crashk_res.end) > - return; > - > - /* > - * To reduce the size of hibernation image, all the pages are > - * marked as Reserved initially. > - */ > - for (addr = crashk_res.start; addr < (crashk_res.end + 1); > - addr += PAGE_SIZE) { > - page = phys_to_page(addr); > - SetPageReserved(page); > - } > -#endif > -} > #else > static void __init reserve_crashkernel(void) > { > } > - > -static void __init kexec_reserve_crashkres_pages(void) > -{ > -} > #endif /* CONFIG_KEXEC_CORE */ > > #ifdef CONFIG_CRASH_DUMP > @@ -586,8 +561,6 @@ void __init mem_init(void) > /* this will put all unused low memory onto the freelists */ > memblock_free_all(); > > - kexec_reserve_crashkres_pages(); > - > mem_init_print_info(NULL); > > /* > -- > 2.17.2 LGTM, so: Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>
On Mon, Jan 14, 2019 at 01:59:01PM +0100, David Hildenbrand wrote: > The crashkernel is reserved via memblock_reserve(). memblock_free_all() > will call free_low_memory_core_early(), which will go over all reserved > memblocks, marking the pages as PG_reserved. > > So manually marking pages as PG_reserved is not necessary, they are > already in the desired state (otherwise they would have been handed over > to the buddy as free pages and bad things would happen). > > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Will Deacon <will.deacon@arm.com> > Cc: James Morse <james.morse@arm.com> > Cc: Bhupesh Sharma <bhsharma@redhat.com> > Cc: David Hildenbrand <david@redhat.com> > Cc: Mark Rutland <mark.rutland@arm.com> > Cc: Dave Kleikamp <dave.kleikamp@oracle.com> > Cc: Andrew Morton <akpm@linux-foundation.org> > Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> > Cc: Michal Hocko <mhocko@suse.com> > Cc: Florian Fainelli <f.fainelli@gmail.com> > Cc: Stefan Agner <stefan@agner.ch> > Cc: Laura Abbott <labbott@redhat.com> > Cc: Greg Hackmann <ghackmann@android.com> > Cc: Johannes Weiner <hannes@cmpxchg.org> > Cc: Kristina Martsenko <kristina.martsenko@arm.com> > Cc: CHANDAN VN <chandan.vn@samsung.com> > Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> > Cc: Logan Gunthorpe <logang@deltatee.com> > Reviewed-by: Matthias Brugger <mbrugger@suse.com> > Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c index 6f0587b5e941..66b5d697d943 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -321,7 +321,7 @@ void crash_post_resume(void) * but does not hold any data of loaded kernel image. * * Note that all the pages in crash dump kernel memory have been initially - * marked as Reserved in kexec_reserve_crashkres_pages(). + * marked as Reserved as memory was allocated via memblock_reserve(). * * In hibernation, the pages which are Reserved and yet "nosave" are excluded * from the hibernation iamge. crash_is_nosave() does thich check for crash diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 7205a9085b4d..c38976b70069 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -118,35 +118,10 @@ static void __init reserve_crashkernel(void) crashk_res.start = crash_base; crashk_res.end = crash_base + crash_size - 1; } - -static void __init kexec_reserve_crashkres_pages(void) -{ -#ifdef CONFIG_HIBERNATION - phys_addr_t addr; - struct page *page; - - if (!crashk_res.end) - return; - - /* - * To reduce the size of hibernation image, all the pages are - * marked as Reserved initially. - */ - for (addr = crashk_res.start; addr < (crashk_res.end + 1); - addr += PAGE_SIZE) { - page = phys_to_page(addr); - SetPageReserved(page); - } -#endif -} #else static void __init reserve_crashkernel(void) { } - -static void __init kexec_reserve_crashkres_pages(void) -{ -} #endif /* CONFIG_KEXEC_CORE */ #ifdef CONFIG_CRASH_DUMP @@ -586,8 +561,6 @@ void __init mem_init(void) /* this will put all unused low memory onto the freelists */ memblock_free_all(); - kexec_reserve_crashkres_pages(); - mem_init_print_info(NULL); /*