From 47fea2adfc9e16846bc57c2f64ff233b354fef39 Mon Sep 17 00:00:00 2001 From: Jaswinder Singh Rajput Date: Mon, 29 Dec 2008 23:39:17 +0530 Subject: sched: sched.c declare variables before they get used Impact: cleanup, avoid sparse warnings In linux/sched.h moved out sysctl_sched_latency, sysctl_sched_min_granularity, sysctl_sched_wakeup_granularity, sysctl_sched_shares_ratelimit and sysctl_sched_shares_thresh from #ifdef CONFIG_SCHED_DEBUG as these variables are common for both. Fixes these sparse warnings: kernel/sched.c:825:14: warning: symbol 'sysctl_sched_shares_ratelimit' was not declared. Should it be static? kernel/sched.c:832:14: warning: symbol 'sysctl_sched_shares_thresh' was not declared. Should it be static? kernel/sched_fair.c:37:14: warning: symbol 'sysctl_sched_latency' was not declared. Should it be static? kernel/sched_fair.c:43:14: warning: symbol 'sysctl_sched_min_granularity' was not declared. Should it be static? kernel/sched_fair.c:72:14: warning: symbol 'sysctl_sched_wakeup_granularity' was not declared. Should it be static? Signed-off-by: Jaswinder Singh Rajput Signed-off-by: Ingo Molnar --- include/linux/sched.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 8395e715809..01d9fd268eb 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1651,16 +1651,16 @@ extern void wake_up_idle_cpu(int cpu); static inline void wake_up_idle_cpu(int cpu) { } #endif -#ifdef CONFIG_SCHED_DEBUG extern unsigned int sysctl_sched_latency; extern unsigned int sysctl_sched_min_granularity; extern unsigned int sysctl_sched_wakeup_granularity; +extern unsigned int sysctl_sched_shares_ratelimit; +extern unsigned int sysctl_sched_shares_thresh; +#ifdef CONFIG_SCHED_DEBUG extern unsigned int sysctl_sched_child_runs_first; extern unsigned int sysctl_sched_features; extern unsigned int sysctl_sched_migration_cost; extern unsigned int sysctl_sched_nr_migrate; -extern unsigned int sysctl_sched_shares_ratelimit; -extern unsigned int sysctl_sched_shares_thresh; int sched_nr_latency_handler(struct ctl_table *table, int write, struct file *file, void __user *buffer, size_t *length, -- cgit v1.2.3-70-g09d2 From c70f22d203fc02c805b6ed4a3483b740dc36786b Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Mon, 5 Jan 2009 19:07:50 +0800 Subject: sched: clean up arch_reinit_sched_domains() - Make arch_reinit_sched_domains() static. It was exported to be used in s390, but now rebuild_sched_domains() is used instead. - Make it return void. Signed-off-by: Li Zefan Signed-off-by: Ingo Molnar --- include/linux/sched.h | 1 - kernel/sched.c | 9 +++------ 2 files changed, 3 insertions(+), 7 deletions(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 38a3f4b1539..91207df702e 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -912,7 +912,6 @@ static inline struct cpumask *sched_domain_span(struct sched_domain *sd) extern void partition_sched_domains(int ndoms_new, struct cpumask *doms_new, struct sched_domain_attr *dattr_new); -extern int arch_reinit_sched_domains(void); /* Test a flag in parent sched domain */ static inline int test_sd_parent(struct sched_domain *sd, int flag) diff --git a/kernel/sched.c b/kernel/sched.c index 9a8e296959c..c5019a5dcaa 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -7987,7 +7987,7 @@ match2: } #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) -int arch_reinit_sched_domains(void) +static void arch_reinit_sched_domains(void) { get_online_cpus(); @@ -7996,13 +7996,10 @@ int arch_reinit_sched_domains(void) rebuild_sched_domains(); put_online_cpus(); - - return 0; } static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt) { - int ret; unsigned int level = 0; if (sscanf(buf, "%u", &level) != 1) @@ -8023,9 +8020,9 @@ static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt) else sched_mc_power_savings = level; - ret = arch_reinit_sched_domains(); + arch_reinit_sched_domains(); - return ret ? ret : count; + return count; } #ifdef CONFIG_SCHED_MC -- cgit v1.2.3-70-g09d2 From 901608d9045146aec6f14a7777ea4b1501c379f0 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Tue, 6 Jan 2009 14:40:29 -0800 Subject: mm: introduce get_mm_hiwater_xxx(), fix taskstats->hiwater_xxx accounting xacct_add_tsk() relies on do_exit()->update_hiwater_xxx() and uses mm->hiwater_xxx directly, this leads to 2 problems: - taskstats_user_cmd() can call fill_pid()->xacct_add_tsk() at any moment before the task exits, so we should check the current values of rss/vm anyway. - do_exit()->update_hiwater_xxx() calls are racy. An exiting thread can be preempted right before mm->hiwater_xxx = new_val, and another thread can use A_LOT of memory and exit in between. When the first thread resumes it can be the last thread in the thread group, in that case we report the wrong hiwater_xxx values which do not take A_LOT into account. Introduce get_mm_hiwater_rss() and get_mm_hiwater_vm() helpers and change xacct_add_tsk() to use them. The first helper will also be used by rusage->ru_maxrss accounting. Kill do_exit()->update_hiwater_xxx() calls. Unless we are going to decrease rss/vm there is no point to update mm->hiwater_xxx, and nobody can look at this mm_struct when exit_mmap() actually unmaps the memory. Signed-off-by: Oleg Nesterov Acked-by: Hugh Dickins Reviewed-by: KOSAKI Motohiro Acked-by: Balbir Singh Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 3 +++ kernel/exit.c | 5 +---- kernel/tsacct.c | 4 ++-- mm/mmap.c | 2 +- 4 files changed, 7 insertions(+), 7 deletions(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 38a3f4b1539..ea415136ac9 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -386,6 +386,9 @@ extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long); (mm)->hiwater_vm = (mm)->total_vm; \ } while (0) +#define get_mm_hiwater_rss(mm) max((mm)->hiwater_rss, get_mm_rss(mm)) +#define get_mm_hiwater_vm(mm) max((mm)->hiwater_vm, (mm)->total_vm) + extern void set_dumpable(struct mm_struct *mm, int value); extern int get_dumpable(struct mm_struct *mm); diff --git a/kernel/exit.c b/kernel/exit.c index f923724ab3c..c7740fa3252 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -1051,10 +1051,7 @@ NORET_TYPE void do_exit(long code) preempt_count()); acct_update_integrals(tsk); - if (tsk->mm) { - update_hiwater_rss(tsk->mm); - update_hiwater_vm(tsk->mm); - } + group_dead = atomic_dec_and_test(&tsk->signal->live); if (group_dead) { hrtimer_cancel(&tsk->signal->real_timer); diff --git a/kernel/tsacct.c b/kernel/tsacct.c index 2dc06ab3571..43f891b05a4 100644 --- a/kernel/tsacct.c +++ b/kernel/tsacct.c @@ -92,8 +92,8 @@ void xacct_add_tsk(struct taskstats *stats, struct task_struct *p) mm = get_task_mm(p); if (mm) { /* adjust to KB unit */ - stats->hiwater_rss = mm->hiwater_rss * PAGE_SIZE / KB; - stats->hiwater_vm = mm->hiwater_vm * PAGE_SIZE / KB; + stats->hiwater_rss = get_mm_hiwater_rss(mm) * PAGE_SIZE / KB; + stats->hiwater_vm = get_mm_hiwater_vm(mm) * PAGE_SIZE / KB; mmput(mm); } stats->read_char = p->ioac.rchar; diff --git a/mm/mmap.c b/mm/mmap.c index e4507b23e62..1f97d8aa9b0 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2102,7 +2102,7 @@ void exit_mmap(struct mm_struct *mm) lru_add_drain(); flush_cache_mm(mm); tlb = tlb_gather_mmu(mm, 1); - /* Don't update_hiwater_rss(mm) here, do_exit already did */ + /* update_hiwater_rss(mm) here? but nobody should be looking */ /* Use -1 here to ensure all VMAs in the mm are unmapped */ end = unmap_vmas(&tlb, vma, 0, -1, &nr_accounted, NULL); vm_unacct_memory(nr_accounted); -- cgit v1.2.3-70-g09d2