From 7602bdf2fd14a40dd9b104e516fdc05e1bd17952 Mon Sep 17 00:00:00 2001 From: Ashwin Chaugule Date: Wed, 6 Dec 2006 20:31:57 -0800 Subject: [PATCH] new scheme to preempt swap token The new swap token patches replace the current token traversal algo. The old algo had a crude timeout parameter that was used to handover the token from one task to another. This algo, transfers the token to the tasks that are in need of the token. The urgency for the token is based on the number of times a task is required to swap-in pages. Accordingly, the priority of a task is incremented if it has been badly affected due to swap-outs. To ensure that the token doesnt bounce around rapidly, the token holders are given a priority boost. The priority of tasks is also decremented, if their rate of swap-in's keeps reducing. This way, the condition to check whether to pre-empt the swap token, is a matter of comparing two task's priority fields. [akpm@osdl.org: cleanups] Signed-off-by: Ashwin Chaugule Cc: Rik van Riel Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index eafe4a7b8237..cad6a16260f7 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -344,9 +344,16 @@ struct mm_struct { /* Architecture-specific MM context */ mm_context_t context; - /* Token based thrashing protection. */ - unsigned long swap_token_time; - char recent_pagein; + /* Swap token stuff */ + /* + * Last value of global fault stamp as seen by this process. + * In other words, this value gives an indication of how long + * it has been since this task got the token. + * Look at mm/thrash.c + */ + unsigned int faultstamp; + unsigned int token_priority; + unsigned int last_interval; /* coredumping support */ int core_waiters; -- cgit v1.2.1 From 36de6437866bbb1d37e2312ff4f95ee4ed6d2b61 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Wed, 6 Dec 2006 20:33:42 -0800 Subject: [PATCH] Save some bytes in struct mm_struct Before: [acme@newtoy net-2.6.20]$ pahole --cacheline 32 kernel/sched.o mm_struct /* include2/asm/processor.h:542 */ struct mm_struct { struct vm_area_struct * mmap; /* 0 4 */ struct rb_root mm_rb; /* 4 4 */ struct vm_area_struct * mmap_cache; /* 8 4 */ long unsigned int (*get_unmapped_area)(); /* 12 4 */ void (*unmap_area)(); /* 16 4 */ long unsigned int mmap_base; /* 20 4 */ long unsigned int task_size; /* 24 4 */ long unsigned int cached_hole_size; /* 28 4 */ /* ---------- cacheline 1 boundary ---------- */ long unsigned int free_area_cache; /* 32 4 */ pgd_t * pgd; /* 36 4 */ atomic_t mm_users; /* 40 4 */ atomic_t mm_count; /* 44 4 */ int map_count; /* 48 4 */ struct rw_semaphore mmap_sem; /* 52 64 */ spinlock_t page_table_lock; /* 116 40 */ struct list_head mmlist; /* 156 8 */ mm_counter_t _file_rss; /* 164 4 */ mm_counter_t _anon_rss; /* 168 4 */ long unsigned int hiwater_rss; /* 172 4 */ long unsigned int hiwater_vm; /* 176 4 */ long unsigned int total_vm; /* 180 4 */ long unsigned int locked_vm; /* 184 4 */ long unsigned int shared_vm; /* 188 4 */ /* ---------- cacheline 6 boundary ---------- */ long unsigned int exec_vm; /* 192 4 */ long unsigned int stack_vm; /* 196 4 */ long unsigned int reserved_vm; /* 200 4 */ long unsigned int def_flags; /* 204 4 */ long unsigned int nr_ptes; /* 208 4 */ long unsigned int start_code; /* 212 4 */ long unsigned int end_code; /* 216 4 */ long unsigned int start_data; /* 220 4 */ /* ---------- cacheline 7 boundary ---------- */ long unsigned int end_data; /* 224 4 */ long unsigned int start_brk; /* 228 4 */ long unsigned int brk; /* 232 4 */ long unsigned int start_stack; /* 236 4 */ long unsigned int arg_start; /* 240 4 */ long unsigned int arg_end; /* 244 4 */ long unsigned int env_start; /* 248 4 */ long unsigned int env_end; /* 252 4 */ /* ---------- cacheline 8 boundary ---------- */ long unsigned int saved_auxv[44]; /* 256 176 */ unsigned int dumpable:2; /* 432 4 */ cpumask_t cpu_vm_mask; /* 436 4 */ mm_context_t context; /* 440 68 */ long unsigned int swap_token_time; /* 508 4 */ /* ---------- cacheline 16 boundary ---------- */ char recent_pagein; /* 512 1 */ /* XXX 3 bytes hole, try to pack */ int core_waiters; /* 516 4 */ struct completion * core_startup_done; /* 520 4 */ struct completion core_done; /* 524 52 */ rwlock_t ioctx_list_lock; /* 576 36 */ struct kioctx * ioctx_list; /* 612 4 */ }; /* size: 616, sum members: 613, holes: 1, sum holes: 3, cachelines: 20, last cacheline: 8 bytes */ After: [acme@newtoy net-2.6.20]$ pahole --cacheline 32 kernel/sched.o mm_struct /* include2/asm/processor.h:542 */ struct mm_struct { struct vm_area_struct * mmap; /* 0 4 */ struct rb_root mm_rb; /* 4 4 */ struct vm_area_struct * mmap_cache; /* 8 4 */ long unsigned int (*get_unmapped_area)(); /* 12 4 */ void (*unmap_area)(); /* 16 4 */ long unsigned int mmap_base; /* 20 4 */ long unsigned int task_size; /* 24 4 */ long unsigned int cached_hole_size; /* 28 4 */ /* ---------- cacheline 1 boundary ---------- */ long unsigned int free_area_cache; /* 32 4 */ pgd_t * pgd; /* 36 4 */ atomic_t mm_users; /* 40 4 */ atomic_t mm_count; /* 44 4 */ int map_count; /* 48 4 */ struct rw_semaphore mmap_sem; /* 52 64 */ spinlock_t page_table_lock; /* 116 40 */ struct list_head mmlist; /* 156 8 */ mm_counter_t _file_rss; /* 164 4 */ mm_counter_t _anon_rss; /* 168 4 */ long unsigned int hiwater_rss; /* 172 4 */ long unsigned int hiwater_vm; /* 176 4 */ long unsigned int total_vm; /* 180 4 */ long unsigned int locked_vm; /* 184 4 */ long unsigned int shared_vm; /* 188 4 */ /* ---------- cacheline 6 boundary ---------- */ long unsigned int exec_vm; /* 192 4 */ long unsigned int stack_vm; /* 196 4 */ long unsigned int reserved_vm; /* 200 4 */ long unsigned int def_flags; /* 204 4 */ long unsigned int nr_ptes; /* 208 4 */ long unsigned int start_code; /* 212 4 */ long unsigned int end_code; /* 216 4 */ long unsigned int start_data; /* 220 4 */ /* ---------- cacheline 7 boundary ---------- */ long unsigned int end_data; /* 224 4 */ long unsigned int start_brk; /* 228 4 */ long unsigned int brk; /* 232 4 */ long unsigned int start_stack; /* 236 4 */ long unsigned int arg_start; /* 240 4 */ long unsigned int arg_end; /* 244 4 */ long unsigned int env_start; /* 248 4 */ long unsigned int env_end; /* 252 4 */ /* ---------- cacheline 8 boundary ---------- */ long unsigned int saved_auxv[44]; /* 256 176 */ cpumask_t cpu_vm_mask; /* 432 4 */ mm_context_t context; /* 436 68 */ long unsigned int swap_token_time; /* 504 4 */ char recent_pagein; /* 508 1 */ unsigned char dumpable:2; /* 509 1 */ /* XXX 2 bytes hole, try to pack */ int core_waiters; /* 512 4 */ struct completion * core_startup_done; /* 516 4 */ struct completion core_done; /* 520 52 */ rwlock_t ioctx_list_lock; /* 572 36 */ struct kioctx * ioctx_list; /* 608 4 */ }; /* size: 612, sum members: 610, holes: 1, sum holes: 2, cachelines: 20, last cacheline: 4 bytes */ [acme@newtoy net-2.6.20]$ codiff -V /tmp/sched.o.before kernel/sched.o /pub/scm/linux/kernel/git/acme/net-2.6.20/kernel/sched.c: struct mm_struct | -4 dumpable:2; from: unsigned int /* 432(30) 4(2) */ to: unsigned char /* 509(6) 1(2) */ < SNIP other offset changes > 1 struct changed [acme@newtoy net-2.6.20]$ I'm not aware of any problem about using 2 byte wide bitfields where previously a 4 byte wide one was, holler if there is any, I wouldn't be surprised, bitfields are things from hell. For the curious, 432(30) means: at offset 432 from the struct start, at offset 30 in the bitfield (yeah, it comes backwards, hellish, huh?) ditto for 509(6), while 4(2) and 1(2) means "struct field size(bitfield size)". Now we have a 2 bytes hole and are using only 4 bytes of the last 32 bytes cacheline, any takers? :-) Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index cad6a16260f7..acfd2e15c5f2 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -338,7 +338,6 @@ struct mm_struct { unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */ - unsigned dumpable:2; cpumask_t cpu_vm_mask; /* Architecture-specific MM context */ @@ -355,6 +354,8 @@ struct mm_struct { unsigned int token_priority; unsigned int last_interval; + unsigned char dumpable:2; + /* coredumping support */ int core_waiters; struct completion *core_startup_done, core_done; -- cgit v1.2.1 From 7dfb71030f7636a0d65200158113c37764552f93 Mon Sep 17 00:00:00 2001 From: Nigel Cunningham Date: Wed, 6 Dec 2006 20:34:23 -0800 Subject: [PATCH] Add include/linux/freezer.h and move definitions from sched.h Move process freezing functions from include/linux/sched.h to freezer.h, so that modifications to the freezer or the kernel configuration don't require recompiling just about everything. [akpm@osdl.org: fix ueagle driver] Signed-off-by: Nigel Cunningham Cc: "Rafael J. Wysocki" Cc: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 81 --------------------------------------------------- 1 file changed, 81 deletions(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index acfd2e15c5f2..837a012f573c 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1618,87 +1618,6 @@ extern int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls); extern void normalize_rt_tasks(void); -#ifdef CONFIG_PM -/* - * Check if a process has been frozen - */ -static inline int frozen(struct task_struct *p) -{ - return p->flags & PF_FROZEN; -} - -/* - * Check if there is a request to freeze a process - */ -static inline int freezing(struct task_struct *p) -{ - return p->flags & PF_FREEZE; -} - -/* - * Request that a process be frozen - * FIXME: SMP problem. We may not modify other process' flags! - */ -static inline void freeze(struct task_struct *p) -{ - p->flags |= PF_FREEZE; -} - -/* - * Sometimes we may need to cancel the previous 'freeze' request - */ -static inline void do_not_freeze(struct task_struct *p) -{ - p->flags &= ~PF_FREEZE; -} - -/* - * Wake up a frozen process - */ -static inline int thaw_process(struct task_struct *p) -{ - if (frozen(p)) { - p->flags &= ~PF_FROZEN; - wake_up_process(p); - return 1; - } - return 0; -} - -/* - * freezing is complete, mark process as frozen - */ -static inline void frozen_process(struct task_struct *p) -{ - p->flags = (p->flags & ~PF_FREEZE) | PF_FROZEN; -} - -extern void refrigerator(void); -extern int freeze_processes(void); -extern void thaw_processes(void); - -static inline int try_to_freeze(void) -{ - if (freezing(current)) { - refrigerator(); - return 1; - } else - return 0; -} -#else -static inline int frozen(struct task_struct *p) { return 0; } -static inline int freezing(struct task_struct *p) { return 0; } -static inline void freeze(struct task_struct *p) { BUG(); } -static inline int thaw_process(struct task_struct *p) { return 1; } -static inline void frozen_process(struct task_struct *p) { BUG(); } - -static inline void refrigerator(void) {} -static inline int freeze_processes(void) { BUG(); return 0; } -static inline void thaw_processes(void) {} - -static inline int try_to_freeze(void) { return 0; } - -#endif /* CONFIG_PM */ #endif /* __KERNEL__ */ #endif -- cgit v1.2.1 From e59e2ae2c29700117a54e85c106017c24837119f Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Wed, 6 Dec 2006 20:35:59 -0800 Subject: [PATCH] SysRq-X: show blocked tasks Add SysRq-X support: show blocked (TASK_UNINTERRUPTIBLE) tasks only. Useful for debugging IO stalls. Signed-off-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 837a012f573c..0a90cefb0b0d 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -194,7 +194,16 @@ extern void init_idle(struct task_struct *idle, int cpu); extern cpumask_t nohz_cpu_mask; -extern void show_state(void); +/* + * Only dump TASK_* tasks. (-1 for all tasks) + */ +extern void show_state_filter(unsigned long state_filter); + +static inline void show_state(void) +{ + show_state_filter(-1); +} + extern void show_regs(struct pt_regs *); /* -- cgit v1.2.1 From d3228a887cae75ef2b8b1211c31c539bef5a5698 Mon Sep 17 00:00:00 2001 From: Adrian Bunk Date: Wed, 6 Dec 2006 20:38:22 -0800 Subject: [PATCH] make kernel/signal.c:kill_proc_info() static Signed-off-by: Adrian Bunk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 0a90cefb0b0d..3a767242e72f 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1305,7 +1305,6 @@ extern int kill_pgrp(struct pid *pid, int sig, int priv); extern int kill_pid(struct pid *pid, int sig, int priv); extern int __kill_pg_info(int sig, struct siginfo *info, pid_t pgrp); extern int kill_pg_info(int, struct siginfo *, pid_t); -extern int kill_proc_info(int, struct siginfo *, pid_t); extern void do_notify_parent(struct task_struct *, int); extern void force_sig(int, struct task_struct *); extern void force_sig_specific(int, struct task_struct *); -- cgit v1.2.1 From 15ad7cdcfd76450d4beebc789ec646664238184d Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Wed, 6 Dec 2006 20:40:36 -0800 Subject: [PATCH] struct seq_operations and struct file_operations constification - move some file_operations structs into the .rodata section - move static strings from policy_types[] array into the .rodata section - fix generic seq_operations usages, so that those structs may be defined as "const" as well [akpm@osdl.org: couple of fixes] Signed-off-by: Helge Deller Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 3a767242e72f..dede82c63445 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -573,7 +573,7 @@ struct sched_info { #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */ #ifdef CONFIG_SCHEDSTATS -extern struct file_operations proc_schedstat_operations; +extern const struct file_operations proc_schedstat_operations; #endif /* CONFIG_SCHEDSTATS */ #ifdef CONFIG_TASK_DELAY_ACCT -- cgit v1.2.1