Re: [PATCH v7 6/6] mm/page_isolation: remove migratetype parameter from more functions.
From: David Hildenbrand
Date: Mon Jun 02 2025 - 16:59:32 EST
On 02.06.25 18:59, Zi Yan wrote:
On 2 Jun 2025, at 11:18, Zi Yan wrote:
migratetype is no longer overwritten during pageblock isolation,
start_isolate_page_range(), has_unmovable_pages(), and
set_migratetype_isolate() no longer need which migratetype to restore
during isolation failure.
For has_unmoable_pages(), it needs to know if the isolation is for CMA
allocation, so adding PB_ISOLATE_MODE_CMA_ALLOC provide the information.
At the same time change isolation flags to enum pb_isolate_mode
(PB_ISOLATE_MODE_MEM_OFFLINE, PB_ISOLATE_MODE_CMA_ALLOC,
PB_ISOLATE_MODE_OTHER). Remove REPORT_FAILURE and check
PB_ISOLATE_MODE_MEM_OFFLINE, since only PB_ISOLATE_MODE_MEM_OFFLINE
reports isolation failures.
alloc_contig_range() no longer needs migratetype. Replace it with
PB_ISOLATE_MODE_CMA_ALLOC to tell if an allocation is for CMA. So does
__alloc_contig_migrate_range().
This paragraph should be changed to:
alloc_contig_range() no longer needs migratetype. Replace it with
a newly defined acr_flags_t to tell if an allocation is for CMA. So does
__alloc_contig_migrate_range(). Add ACR_OTHER (set to 0) to indicate
other cases.
Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>
---
drivers/virtio/virtio_mem.c | 4 +-
include/linux/gfp.h | 18 ++++++++-
include/linux/page-isolation.h | 7 +---
include/trace/events/kmem.h | 14 ++++---
mm/cma.c | 3 +-
mm/memory_hotplug.c | 6 +--
mm/page_alloc.c | 27 ++++++-------
mm/page_isolation.c | 70 +++++++++++++++-------------------
8 files changed, 79 insertions(+), 70 deletions(-)
The fixup to restore acr_flags_t:
From d0205580ab70aaf93f3f7c04b53dc595ee387bac Mon Sep 17 00:00:00 2001
From: Zi Yan <ziy@xxxxxxxxxx>
Date: Mon, 2 Jun 2025 12:53:58 -0400
Subject: [PATCH] restore acr_flags_t.
Signed-off-by: Zi Yan <ziy@xxxxxxxxxx>
---
drivers/virtio/virtio_mem.c | 4 ++--
include/linux/gfp.h | 21 +++++----------------
include/linux/page-isolation.h | 15 +++++++++++++++
include/trace/events/kmem.h | 12 ++++++------
mm/cma.c | 3 +--
mm/page_alloc.c | 24 ++++++++++++------------
6 files changed, 41 insertions(+), 38 deletions(-)
diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
index 535680a54ff5..6bce70b139b2 100644
--- a/drivers/virtio/virtio_mem.c
+++ b/drivers/virtio/virtio_mem.c
@@ -1243,8 +1243,8 @@ static int virtio_mem_fake_offline(struct virtio_mem *vm, unsigned long pfn,
if (atomic_read(&vm->config_changed))
return -EAGAIN;
- rc = alloc_contig_range(pfn, pfn + nr_pages,
- PB_ISOLATE_MODE_OTHER, GFP_KERNEL);
+ rc = alloc_contig_range(pfn, pfn + nr_pages, ACR_OTHER,
+ GFP_KERNEL);
if (rc == -ENOMEM)
/* whoops, out of memory */
return rc;
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 17b92888d6de..95065cec85e5 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -423,25 +423,14 @@ static inline bool gfp_compaction_allowed(gfp_t gfp_mask)
extern gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma);
#ifdef CONFIG_CONTIG_ALLOC
-/*
- * Pageblock isolation modes:
- * PB_ISOLATE_MODE_MEM_OFFLINE - isolate to offline (!allocate) memory
- * e.g., skip over PageHWPoison() pages and
- * PageOffline() pages. Unmovable pages will be
- * reported in this mode.
- * PB_ISOLATE_MODE_CMA_ALLOC - isolate for CMA allocations
- * PB_ISOLATE_MODE_OTHER - isolate for other purposes
- */
-enum pb_isolate_mode {
- PB_ISOLATE_MODE_MEM_OFFLINE,
- PB_ISOLATE_MODE_CMA_ALLOC,
- PB_ISOLATE_MODE_OTHER,
-};
+
+typedef unsigned int __bitwise acr_flags_t;
+#define ACR_OTHER ((__force acr_flags_t)0) // other allocations
+#define ACR_CMA ((__force acr_flags_t)BIT(0)) // allocate for CMA
For FPI I called that "FPI_NONE" -- no special request -- and similarly
for RMAP "RMAP_NONE".
So if ACR_CMA is set, it's a CMA allocation, otherwise just an ordinary one.
Apart from that LGTM.
--
Cheers,
David / dhildenb