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charset=us-ascii Content-Disposition: inline In-Reply-To: <20240827190916.34242-1-urezki@gmail.com> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.15 X-Rspamd-Queue-Id: 4A3DF160008 X-Stat-Signature: mhpupo3sxeffpxbj494e6ngecnndcayi X-Rspamd-Server: rspam09 X-Rspam-User: X-HE-Tag: 1724903326-574008 X-HE-Meta: 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 V9Rygwa8 ro0f6opuPotNUabza8YBh1ql+2WNvdFl9VGGP26KGxmMsBN/kQ5Vg+P+ZI9jM1pKiskZt4H4m29N9JAXDBsFUvWImLV7caHYY0e5E2nCrId49aRJ017+w+vyDxnkqiw3q8OMV4DJqS2lSt3FyrwclEa8QFI1Csvkg5FznRyyw8ZKA3SkEDxjiiYmJbRDWBEiKVe4dqS5ykeCxml+RRD/xZjYKlliIxkHxxV3x4Lhar9YnuFOUi6Flqz4VrpZKlZSfs1GhINF/XyueQVB+VfoDQN7D00RcvtmMyNJIPkg5/Tw3igfHgFZ8rYVzqnemXE7urQVS4tbWbldPY9ZWi0/LMwrkjSq+sbaOmCXQHr9YSnSBdJdv/XQp05XVV8gGLDgzclsTrtg1m09YaGU9oUR4jgPBgRgMVQ+V7HYmwmsmOdJoC9RrXtusrr6XWuZd8ZVuo9Us X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 08/27/24 at 09:09pm, Uladzislau Rezki (Sony) wrote: > The aim is to simplify and making the vm_area_alloc_pages() > function less confusing as it became more clogged nowadays: > > - eliminate a "bulk_gfp" variable and do not overwrite a gfp > flag for bulk allocator; > - drop __GFP_NOFAIL flag for high-order-page requests on upper > layer. It becomes less spread between levels when it comes to > __GFP_NOFAIL allocations; > - add a comment about a fallback path if high-order attempt is > unsuccessful because for such cases __GFP_NOFAIL is dropped; > - fix a typo in a commit message. > > Signed-off-by: Uladzislau Rezki (Sony) > --- > mm/vmalloc.c | 37 +++++++++++++++++-------------------- > 1 file changed, 17 insertions(+), 20 deletions(-) > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index 3f9b6bd707d2..57862865e808 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -3531,8 +3531,6 @@ vm_area_alloc_pages(gfp_t gfp, int nid, > unsigned int order, unsigned int nr_pages, struct page **pages) > { > unsigned int nr_allocated = 0; > - gfp_t alloc_gfp = gfp; > - bool nofail = gfp & __GFP_NOFAIL; > struct page *page; > int i; > > @@ -3543,9 +3541,6 @@ vm_area_alloc_pages(gfp_t gfp, int nid, > * more permissive. > */ > if (!order) { > - /* bulk allocator doesn't support nofail req. officially */ > - gfp_t bulk_gfp = gfp & ~__GFP_NOFAIL; > - > while (nr_allocated < nr_pages) { > unsigned int nr, nr_pages_request; > > @@ -3563,12 +3558,11 @@ vm_area_alloc_pages(gfp_t gfp, int nid, > * but mempolicy wants to alloc memory by interleaving. > */ > if (IS_ENABLED(CONFIG_NUMA) && nid == NUMA_NO_NODE) > - nr = alloc_pages_bulk_array_mempolicy_noprof(bulk_gfp, > + nr = alloc_pages_bulk_array_mempolicy_noprof(gfp, > nr_pages_request, > pages + nr_allocated); > - > else > - nr = alloc_pages_bulk_array_node_noprof(bulk_gfp, nid, > + nr = alloc_pages_bulk_array_node_noprof(gfp, nid, > nr_pages_request, > pages + nr_allocated); > > @@ -3582,30 +3576,24 @@ vm_area_alloc_pages(gfp_t gfp, int nid, > if (nr != nr_pages_request) > break; > } > - } else if (gfp & __GFP_NOFAIL) { > - /* > - * Higher order nofail allocations are really expensive and > - * potentially dangerous (pre-mature OOM, disruptive reclaim > - * and compaction etc. > - */ > - alloc_gfp &= ~__GFP_NOFAIL; > } > > /* High-order pages or fallback path if "bulk" fails. */ > while (nr_allocated < nr_pages) { > - if (!nofail && fatal_signal_pending(current)) > + if (!(gfp & __GFP_NOFAIL) && fatal_signal_pending(current)) > break; > > if (nid == NUMA_NO_NODE) > - page = alloc_pages_noprof(alloc_gfp, order); > + page = alloc_pages_noprof(gfp, order); > else > - page = alloc_pages_node_noprof(nid, alloc_gfp, order); > + page = alloc_pages_node_noprof(nid, gfp, order); > + > if (unlikely(!page)) > break; > > /* > * Higher order allocations must be able to be treated as > - * indepdenent small pages by callers (as they can with > + * independent small pages by callers (as they can with > * small-page vmallocs). Some drivers do their own refcounting > * on vmalloc_to_page() pages, some use page->mapping, > * page->lru, etc. > @@ -3666,7 +3654,16 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, > set_vm_area_page_order(area, page_shift - PAGE_SHIFT); > page_order = vm_area_page_order(area); > > - area->nr_pages = vm_area_alloc_pages(gfp_mask | __GFP_NOWARN, > + /* > + * Higher order nofail allocations are really expensive and ~~~~~~~~~~~~ Seems we use both higher-order and high-order to describe the non 0-order pages in many places. I personally would take high-order, higher-order seems to be a little confusing because it's not explicit what is compared with and lower. Surely this is not an issue to this patch, I see a lot of 'higher order' in kernel codes. For this patch, Reviewed-by: Baoquan He > + * potentially dangerous (pre-mature OOM, disruptive reclaim > + * and compaction etc. > + * > + * Please note, the __vmalloc_node_range_noprof() falls-back > + * to order-0 pages if high-order attempt is unsuccessful. > + */ > + area->nr_pages = vm_area_alloc_pages((page_order ? > + gfp_mask & ~__GFP_NOFAIL : gfp_mask) | __GFP_NOWARN, > node, page_order, nr_small_pages, area->pages); > > atomic_long_add(area->nr_pages, &nr_vmalloc_pages); > -- > 2.39.2 >