On Tue, 28 Jan 2025, Andrew Morton wrote:
From: "Ritesh Harjani (IBM)" ritesh.list@gmail.com Subject: mm/hugetlb: fix hugepage allocation for interleaved memory nodes Date: Sat, 11 Jan 2025 16:36:55 +0530
gather_bootmem_prealloc() assumes the start nid as 0 and size as num_node_state(N_MEMORY). That means in case if memory attached numa nodes are interleaved, then gather_bootmem_prealloc_parallel() will fail to scan few of these nodes.
Since memory attached numa nodes can be interleaved in any fashion, hence ensure that the current code checks for all numa node ids (.size = nr_node_ids). Let's still keep max_threads as N_MEMORY, so that it can distributes all nr_node_ids among the these many no. threads.
e.g. qemu cmdline
numa_cmd="-numa node,nodeid=1,memdev=mem1,cpus=2-3 -numa node,nodeid=0,cpus=0-1 -numa dist,src=0,dst=1,val=20" mem_cmd="-object memory-backend-ram,id=mem1,size=16G"
w/o this patch for cmdline (default_hugepagesz=1GB hugepagesz=1GB hugepages=2):
~ # cat /proc/meminfo |grep -i huge AnonHugePages: 0 kB ShmemHugePages: 0 kB FileHugePages: 0 kB HugePages_Total: 0 HugePages_Free: 0 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 1048576 kB Hugetlb: 0 kB
with this patch for cmdline (default_hugepagesz=1GB hugepagesz=1GB hugepages=2):
~ # cat /proc/meminfo |grep -i huge AnonHugePages: 0 kB ShmemHugePages: 0 kB FileHugePages: 0 kB HugePages_Total: 2 HugePages_Free: 2 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 1048576 kB Hugetlb: 2097152 kB
Link: https://lkml.kernel.org/r/f8d8dad3a5471d284f54185f65d575a6aaab692b.173659253... Fixes: b78b27d02930 ("hugetlb: parallelize 1G hugetlb initialization") Signed-off-by: Ritesh Harjani (IBM) ritesh.list@gmail.com Reported-by: Pavithra Prakash pavrampu@linux.ibm.com Suggested-by: Muchun Song muchun.song@linux.dev Tested-by: Sourabh Jain sourabhjain@linux.ibm.com Reviewed-by: Luiz Capitulino luizcap@redhat.com Cc: Donet Tom donettom@linux.ibm.com Cc: Gang Li gang.li@linux.dev Cc: Daniel Jordan daniel.m.jordan@oracle.com Cc: David Rientjes rientjes@google.com
Acked-by: David Rientjes rientjes@google.com
Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org