From 3218ae14b1e3ee2ab81df30ed690c8e864d23316 Mon Sep 17 00:00:00 2001 From: Yasunori Goto Date: Tue, 27 Jun 2006 02:53:33 -0700 Subject: [PATCH] [PATCH] pgdat allocation for new node add (export kswapd start func) When node is hot-added, kswapd for the node should start. This export kswapd start function as kswapd_run() to use at add_memory(). [akpm@osdl.org: daemonize() isn't needed when using the kthread API] Signed-off-by: Yasunori Goto Signed-off-by: KAMEZAWA Hiroyuki Cc: Dave Hansen Cc: "Brown, Len" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/swap.h | 2 ++ mm/vmscan.c | 37 ++++++++++++++++++++++++++----------- 2 files changed, 28 insertions(+), 11 deletions(-) diff --git a/include/linux/swap.h b/include/linux/swap.h index dc3f3aa0c83e..c41e2d6d1acc 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -199,6 +199,8 @@ static inline int zone_reclaim(struct zone *z, gfp_t mask, unsigned int order) } #endif +extern int kswapd_run(int nid); + #ifdef CONFIG_MMU /* linux/mm/shmem.c */ extern int shmem_unuse(swp_entry_t entry, struct page *page); diff --git a/mm/vmscan.c b/mm/vmscan.c index 72babac71dea..f03da33d9147 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -34,6 +34,7 @@ #include #include #include +#include #include #include @@ -1223,7 +1224,6 @@ static int kswapd(void *p) }; cpumask_t cpumask; - daemonize("kswapd%d", pgdat->node_id); cpumask = node_to_cpumask(pgdat->node_id); if (!cpus_empty(cpumask)) set_cpus_allowed(tsk, cpumask); @@ -1468,20 +1468,35 @@ static int cpu_callback(struct notifier_block *nfb, } #endif /* CONFIG_HOTPLUG_CPU */ +/* + * This kswapd start function will be called by init and node-hot-add. + * On node-hot-add, kswapd will moved to proper cpus if cpus are hot-added. + */ +int kswapd_run(int nid) +{ + pg_data_t *pgdat = NODE_DATA(nid); + int ret = 0; + + if (pgdat->kswapd) + return 0; + + pgdat->kswapd = kthread_run(kswapd, pgdat, "kswapd%d", nid); + if (IS_ERR(pgdat->kswapd)) { + /* failure at boot is fatal */ + BUG_ON(system_state == SYSTEM_BOOTING); + printk("Failed to start kswapd on node %d\n",nid); + ret = -1; + } + return ret; +} + static int __init kswapd_init(void) { - pg_data_t *pgdat; + int nid; swap_setup(); - for_each_online_pgdat(pgdat) { - pid_t pid; - - pid = kernel_thread(kswapd, pgdat, CLONE_KERNEL); - BUG_ON(pid < 0); - read_lock(&tasklist_lock); - pgdat->kswapd = find_task_by_pid(pid); - read_unlock(&tasklist_lock); - } + for_each_online_node(nid) + kswapd_run(nid); hotcpu_notifier(cpu_callback, 0); return 0; } -- 2.39.5