From: Eugeniu Rosca <erosca@de.adit-jv.com>
To: Matthew Wilcox <willy@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Michal Hocko <mhocko@suse.com>,
Catalin Marinas <catalin.marinas@arm.com>,
Ard Biesheuvel <ard.biesheuvel@linaro.org>,
Steven Sistare <steven.sistare@oracle.com>,
AKASHI Takahiro <takahiro.akashi@linaro.org>,
Pavel Tatashin <pasha.tatashin@oracle.com>,
Gioh Kim <gi-oh.kim@profitbricks.com>,
Heiko Carstens <heiko.carstens@de.ibm.com>,
Wei Yang <richard.weiyang@gmail.com>,
Miles Chen <miles.chen@mediatek.com>,
Vlastimil Babka <vbabka@suse.cz>, Mel Gorman <mgorman@suse.de>,
Johannes Weiner <hannes@cmpxchg.org>,
Paul Burton <paul.burton@mips.com>,
James Hartley <james.hartley@mips.com>,
<linux-kernel@vger.kernel.org>, <linux-mm@kvack.org>
Subject: Re: [PATCH v2 1/1] mm: page_alloc: skip over regions of invalid pfns on UMA
Date: Mon, 22 Jan 2018 21:25:30 +0100 [thread overview]
Message-ID: <20180122202530.GA24724@vmlxhi-102.adit-jv.com> (raw)
In-Reply-To: <20180122012156.GA10428@bombadil.infradead.org>
Hi Matthew and thanks for your feedback and review comments!
On Sun, Jan 21, 2018 at 05:21:56PM -0800, Matthew Wilcox wrote:
>
> I like the patch. I think it could be better.
>
> > +++ b/mm/page_alloc.c
> > @@ -5344,7 +5344,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
> > goto not_early;
> >
> > if (!early_pfn_valid(pfn)) {
> > -#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
> > +#ifdef CONFIG_HAVE_MEMBLOCK
> > /*
> > * Skip to the pfn preceding the next valid one (or
> > * end_pfn), such that we hit a valid pfn (or end_pfn)
>
> This ifdef makes me sad. Here's more of the context:
>
> if (!early_pfn_valid(pfn)) {
> #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
> /*
> * Skip to the pfn preceding the next valid one (or
> * end_pfn), such that we hit a valid pfn (or end_pfn)
> * on our next iteration of the loop.
> */
> pfn = memblock_next_valid_pfn(pfn, end_pfn) - 1;
> #endif
> continue;
> }
>
> This is crying out for:
>
> #ifdef CONFIG_HAVE_MEMBLOCK
> unsigned long memblock_next_valid_pfn(unsigned long pfn, unsigned long max_pfn);
> #else
> static inline unsigned long memblock_next_valid_pfn(unsigned long pfn,
> unsigned long max_pfn)
> {
> return pfn + 1;
> }
> #endif
>
> in a header file somewhere.
>
Here is what I came up with, based on your proposal:
---------------------------------------------------------
diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 7ed0f7782d16..9efd592c5da4 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -187,7 +187,6 @@ int memblock_search_pfn_nid(unsigned long pfn, unsigned long *start_pfn,
unsigned long *end_pfn);
void __next_mem_pfn_range(int *idx, int nid, unsigned long *out_start_pfn,
unsigned long *out_end_pfn, int *out_nid);
-unsigned long memblock_next_valid_pfn(unsigned long pfn, unsigned long max_pfn);
/**
* for_each_mem_pfn_range - early memory pfn range iterator
diff --git a/include/linux/mm.h b/include/linux/mm.h
index ea818ff739cd..b82b30522585 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2064,8 +2064,14 @@ extern int __meminit __early_pfn_to_nid(unsigned long pfn,
#ifdef CONFIG_HAVE_MEMBLOCK
void zero_resv_unavail(void);
+unsigned long memblock_next_valid_pfn(unsigned long pfn, unsigned long max_pfn);
#else
static inline void zero_resv_unavail(void) {}
+static inline unsigned long memblock_next_valid_pfn(unsigned long pfn,
+ unsigned long max_pfn)
+{
+ return pfn + 1;
+}
#endif
extern void set_dma_reserve(unsigned long new_dma_reserve);
diff --git a/mm/memblock.c b/mm/memblock.c
index 46aacdfa4f4d..ad48cf200e3b 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -1100,6 +1100,7 @@ void __init_memblock __next_mem_pfn_range(int *idx, int nid,
if (out_nid)
*out_nid = r->nid;
}
+#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
unsigned long __init_memblock memblock_next_valid_pfn(unsigned long pfn,
unsigned long max_pfn)
@@ -1129,6 +1130,7 @@ unsigned long __init_memblock memblock_next_valid_pfn(unsigned long pfn,
return min(PHYS_PFN(type->regions[right].base), max_pfn);
}
+#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
/**
* memblock_set_node - set node ID on memblock regions
* @base: base of area to set node ID for
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 76c9688b6a0a..4a3d5936a9a0 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5344,14 +5344,12 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
goto not_early;
if (!early_pfn_valid(pfn)) {
-#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
/*
* Skip to the pfn preceding the next valid one (or
* end_pfn), such that we hit a valid pfn (or end_pfn)
* on our next iteration of the loop.
*/
pfn = memblock_next_valid_pfn(pfn, end_pfn) - 1;
-#endif
continue;
}
if (!early_pfn_in_nid(pfn, nid))
---------------------------------------------------------
Here are the sanity checks and tests done (all on v4.15-rc9):
- compiled natively on x86_64
- cross-compiled for ARCH=arm64 (NUMA=y/n), ARCH=tile (for which kbuild
test robot reported a build failure with [PATCH v1])
- no new issues reported by:
- checkpatch --strict
- make W=1
- make CHECK="/path/to/smatch -p=kernel --two-passes --spammy" C=2 mm/
- make C=2 CF="-D__CHECK_ENDIAN__" -Wunused-function mm/
- cppcheck --force --enable=all --inconclusive mm/
- re-tested on H3ULCB and confirmed the same behavior as with [PATCH v2]
If no other comments, I will submit [PATCH v3] in the next days.
Many thanks!
Best regards,
Eugeniu,
next prev parent reply other threads:[~2018-01-22 20:25 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-21 14:47 [PATCH v2 0/1] Skip over regions of invalid pfns with NUMA=n && HAVE_MEMBLOCK=y Eugeniu Rosca
2018-01-21 14:47 ` [PATCH v2 1/1] mm: page_alloc: skip over regions of invalid pfns on UMA Eugeniu Rosca
2018-01-22 1:21 ` Matthew Wilcox
2018-01-22 20:25 ` Eugeniu Rosca [this message]
2018-01-23 0:45 ` Matthew Wilcox
2018-01-23 19:00 ` Eugeniu Rosca
2018-01-23 20:27 ` Matthew Wilcox
2018-01-24 14:51 ` Eugeniu Rosca
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180122202530.GA24724@vmlxhi-102.adit-jv.com \
--to=erosca@de.adit-jv.com \
--cc=akpm@linux-foundation.org \
--cc=ard.biesheuvel@linaro.org \
--cc=catalin.marinas@arm.com \
--cc=gi-oh.kim@profitbricks.com \
--cc=hannes@cmpxchg.org \
--cc=heiko.carstens@de.ibm.com \
--cc=james.hartley@mips.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@suse.de \
--cc=mhocko@suse.com \
--cc=miles.chen@mediatek.com \
--cc=pasha.tatashin@oracle.com \
--cc=paul.burton@mips.com \
--cc=richard.weiyang@gmail.com \
--cc=steven.sistare@oracle.com \
--cc=takahiro.akashi@linaro.org \
--cc=vbabka@suse.cz \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).