From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f198.google.com (mail-pf1-f198.google.com [209.85.210.198]) by kanga.kvack.org (Postfix) with ESMTP id 7A3416B6E08 for ; Tue, 4 Dec 2018 04:59:55 -0500 (EST) Received: by mail-pf1-f198.google.com with SMTP id u20so13619237pfa.1 for ; Tue, 04 Dec 2018 01:59:55 -0800 (PST) Received: from ozlabs.org (ozlabs.org. [2401:3900:2:1::2]) by mx.google.com with ESMTPS id g7si17886829plb.107.2018.12.04.01.59.53 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 04 Dec 2018 01:59:54 -0800 (PST) From: Michael Ellerman Subject: Re: [PATCH v2 1/6] powerpc: prefer memblock APIs returning virtual address In-Reply-To: <1543852035-26634-2-git-send-email-rppt@linux.ibm.com> References: <1543852035-26634-1-git-send-email-rppt@linux.ibm.com> <1543852035-26634-2-git-send-email-rppt@linux.ibm.com> Date: Tue, 04 Dec 2018 20:59:41 +1100 Message-ID: <87woophasy.fsf@concordia.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: Mike Rapoport , Andrew Morton Cc: Arnd Bergmann , Benjamin Herrenschmidt , "David S. Miller" , Guan Xuetao , Greentime Hu , Jonas Bonn , Michal Hocko , Michal Simek , Mark Salter , Paul Mackerras , Rich Felker , Russell King , Stefan Kristiansson , Stafford Horne , Vincent Chen , Yoshinori Sato , linux-arm-kernel@lists.infradead.org, linux-c6x-dev@linux-c6x.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-sh@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, openrisc@lists.librecores.org, sparclinux@vger.kernel.org Hi Mike, Thanks for trying to clean these up. I think a few could be improved though ... Mike Rapoport writes: > diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c > index 913bfca..fa884ad 100644 > --- a/arch/powerpc/kernel/paca.c > +++ b/arch/powerpc/kernel/paca.c > @@ -42,17 +42,15 @@ static void *__init alloc_paca_data(unsigned long size, unsigned long align, > nid = early_cpu_to_node(cpu); > } > > - pa = memblock_alloc_base_nid(size, align, limit, nid, MEMBLOCK_NONE); > - if (!pa) { > - pa = memblock_alloc_base(size, align, limit); > - if (!pa) > - panic("cannot allocate paca data"); > - } > + ptr = memblock_alloc_try_nid_raw(size, align, MEMBLOCK_LOW_LIMIT, > + limit, nid); > + if (!ptr) > + panic("cannot allocate paca data"); The old code doesn't zero, but two of the three callers of alloc_paca_data() *do* zero the whole allocation, so I'd be happy if we did it in here instead. That would mean we could use memblock_alloc_try_nid() avoiding the need to panic() manually. > diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c > index 236c115..d11ee7f 100644 > --- a/arch/powerpc/kernel/setup_64.c > +++ b/arch/powerpc/kernel/setup_64.c > @@ -634,19 +634,17 @@ __init u64 ppc64_bolted_size(void) > > static void *__init alloc_stack(unsigned long limit, int cpu) > { > - unsigned long pa; > + void *ptr; > > BUILD_BUG_ON(STACK_INT_FRAME_SIZE % 16); > > - pa = memblock_alloc_base_nid(THREAD_SIZE, THREAD_SIZE, limit, > - early_cpu_to_node(cpu), MEMBLOCK_NONE); > - if (!pa) { > - pa = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit); > - if (!pa) > - panic("cannot allocate stacks"); > - } > + ptr = memblock_alloc_try_nid_raw(THREAD_SIZE, THREAD_SIZE, > + MEMBLOCK_LOW_LIMIT, limit, > + early_cpu_to_node(cpu)); > + if (!ptr) > + panic("cannot allocate stacks"); Similarly here, several of the callers zero the stack, and I'd rather all of them did. So again we could use memblock_alloc_try_nid() here and remove the memset()s from emergency_stack_init(). > diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c > index 9311560..415a1eb0 100644 > --- a/arch/powerpc/mm/pgtable-radix.c > +++ b/arch/powerpc/mm/pgtable-radix.c > @@ -51,24 +51,18 @@ static int native_register_process_table(unsigned long base, unsigned long pg_sz > static __ref void *early_alloc_pgtable(unsigned long size, int nid, > unsigned long region_start, unsigned long region_end) > { > - unsigned long pa = 0; > + phys_addr_t min_addr = MEMBLOCK_LOW_LIMIT; > + phys_addr_t max_addr = MEMBLOCK_ALLOC_ANYWHERE; > void *pt; > > - if (region_start || region_end) /* has region hint */ > - pa = memblock_alloc_range(size, size, region_start, region_end, > - MEMBLOCK_NONE); > - else if (nid != -1) /* has node hint */ > - pa = memblock_alloc_base_nid(size, size, > - MEMBLOCK_ALLOC_ANYWHERE, > - nid, MEMBLOCK_NONE); > + if (region_start) > + min_addr = region_start; > + if (region_end) > + max_addr = region_end; > > - if (!pa) > - pa = memblock_alloc_base(size, size, MEMBLOCK_ALLOC_ANYWHERE); > - > - BUG_ON(!pa); > - > - pt = __va(pa); > - memset(pt, 0, size); > + pt = memblock_alloc_try_nid_nopanic(size, size, min_addr, max_addr, > + nid); > + BUG_ON(!pt); I don't think there's any reason to BUG_ON() here rather than letting memblock() call panic() for us. So this could also be memblock_alloc_try_nid(). > diff --git a/arch/powerpc/platforms/pasemi/iommu.c b/arch/powerpc/platforms/pasemi/iommu.c > index f297152..f62930f 100644 > --- a/arch/powerpc/platforms/pasemi/iommu.c > +++ b/arch/powerpc/platforms/pasemi/iommu.c > @@ -208,7 +208,9 @@ static int __init iob_init(struct device_node *dn) > pr_debug(" -> %s\n", __func__); > > /* For 2G space, 8x64 pages (2^21 bytes) is max total l2 size */ > - iob_l2_base = (u32 *)__va(memblock_alloc_base(1UL<<21, 1UL<<21, 0x80000000)); > + iob_l2_base = memblock_alloc_try_nid_raw(1UL << 21, 1UL << 21, > + MEMBLOCK_LOW_LIMIT, 0x80000000, > + NUMA_NO_NODE); This isn't equivalent is it? memblock_alloc_base() panics on failure but memblock_alloc_try_nid_raw() doesn't? Same comment for the other locations that do that conversion. cheers