diff --git a/mm/oom_panic.c b/mm/oom_panic.c new file mode 100644 index 0000000..4230ae5 --- /dev/null +++ b/mm/oom_panic.c @@ -0,0 +1,51 @@ +/* + * Just panic() instead of the default behavior of selecting processes + * for death. + * + * Based on + * Modular OOM handlers for 2.6.4 (C) 2003,2004 Tvrtko A. Ursulin + * and + * linux/mm/oom_kill.c (C) 1998,2000 Rik van Riel. + * + * Mark Huang + * + * $Id: oom_panic.c,v 1.1 2004/10/01 17:54:48 mlhuang Exp $ + */ + +#include +#include +#include + +/** + * out_of_memory - is the system out of memory? + */ +void out_of_memory(int gfp_mask) +{ + /* + * oom_lock protects out_of_memory()'s static variables. + * It's a global lock; this is not performance-critical. + */ + static spinlock_t oom_lock = SPIN_LOCK_UNLOCKED; + static unsigned long count; + + spin_lock(&oom_lock); + + /* + * If we have gotten only a few failures, + * we're not really oom. + */ + if (++count < 10) + goto out_unlock; + + /* + * Ok, really out of memory. Panic. + */ + + printk("oom-killer: gfp_mask=0x%x\n", gfp_mask); + show_free_areas(); + + panic("Out Of Memory"); + +out_unlock: + spin_unlock(&oom_lock); +} diff --git a/init/Kconfig b/init/Kconfig index 87fe242..cc782ea 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -548,6 +548,23 @@ config CGROUP_DEVICE Provides a cgroup implementing whitelists for devices which a process in the cgroup can mknod or open. +config OOM_PANIC + bool "OOM Panic" + default y + ---help--- + This option enables panic() to be called when a system is out of + memory. This feature along with /proc/sys/kernel/panic allows a + different behavior on out-of-memory conditions when the standard + behavior (killing processes in an attempt to recover) does not + make sense. + + If unsure, say N. + +config OOM_KILL + bool + depends on !OOM_PANIC + default y + config CPUSETS bool "Cpuset support" depends on CGROUPS diff --git a/mm/oom_kill.c b/mm/oom_kill.c index e0ba2e1..bb123cf 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -209,6 +209,11 @@ unsigned long badness(struct task_struct *p, unsigned long uptime) return points; } +#if defined(CONFIG_OOM_PANIC) && defined(CONFIG_OOM_KILLER) +#warning Only define OOM_PANIC or OOM_KILLER; not both +#endif + +#ifdef CONFIG_OOM_KILLER /* * Determine the type of allocation constraint. */ @@ -479,6 +484,7 @@ retry: out: read_unlock(&tasklist_lock); } + #endif static BLOCKING_NOTIFIER_HEAD(oom_notify_list); @@ -544,6 +550,7 @@ void clear_zonelist_oom(struct zonelist *zonelist, gfp_t gfp_mask) } spin_unlock(&zone_scan_lock); } +EXPORT_SYMBOL_GPL(clear_zonelist_oom); long vs_oom_action(unsigned int); @@ -675,3 +682,47 @@ void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order) if (!test_thread_flag(TIF_MEMDIE)) schedule_timeout_uninterruptible(1); } +#endif /* CONFIG_OOM_KILLER */ + +#ifdef CONFIG_OOM_PANIC +/** + * out_of_memory - panic if the system out of memory? + */ +void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order) +{ + /* + * oom_lock protects out_of_memory()'s static variables. + * It's a global lock; this is not performance-critical. + */ + static spinlock_t oom_lock = SPIN_LOCK_UNLOCKED; + static unsigned long count; + + spin_lock(&oom_lock); + + /* + * If we have gotten only a few failures, + * we're not really oom. + */ + if (++count >= 10) { + /* + * Ok, really out of memory. Panic. + */ + + printk("oom-killer: gfp_mask=0x%x\n", gfp_mask); + show_free_areas(); + + panic("Out Of Memory"); + } + spin_unlock(&oom_lock); +} + +#ifdef CONFIG_CGROUP_MEM_RES_CTLR +void mem_cgroup_out_of_memory(struct mem_cgroup *mem, gfp_t gfp_mask) +{ + cgroup_lock(); + panic("Memory cgroup out Of Memory"); + cgroup_unlock(); +} + +#endif +#endif /* CONFIG_OOM_PANIC */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 4b70600..4830639 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1642,11 +1642,13 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, { struct page *page; +#ifdef CONFIG_OOM_KILLER /* Acquire the OOM killer lock for the zones in zonelist */ if (!try_set_zone_oom(zonelist, gfp_mask)) { schedule_timeout_uninterruptible(1); return NULL; } +#endif /* * Go through the zonelist yet one more time, keep very high watermark @@ -1668,7 +1670,9 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, out_of_memory(zonelist, gfp_mask, order); out: +#ifdef CONFIG_OOM_KILLER clear_zonelist_oom(zonelist, gfp_mask); +#endif return page; }