From 464763cf1c6df632dccc8f2f4c7e50163154a2c0 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 17 Dec 2009 13:16:29 +0100 Subject: sched: Update task_state_arraypwith new states Neglected because its hidden... (who reads comments anyway) Signed-off-by: Peter Zijlstra LKML-Reference: <20091217121829.970166036@chello.nl> Signed-off-by: Ingo Molnar --- fs/proc/array.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'fs/proc/array.c') diff --git a/fs/proc/array.c b/fs/proc/array.c index 4badde179b1..96361e8fa3a 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -138,9 +138,12 @@ static const char *task_state_array[] = { "S (sleeping)", /* 1 */ "D (disk sleep)", /* 2 */ "T (stopped)", /* 4 */ - "T (tracing stop)", /* 8 */ + "t (tracing stop)", /* 8 */ "Z (zombie)", /* 16 */ - "X (dead)" /* 32 */ + "X (dead)", /* 32 */ + "x (dead)", /* 64 */ + "K (wakekill)", /* 128 */ + "W (waking)", /* 256 */ }; static inline const char *get_task_state(struct task_struct *tsk) -- cgit v1.2.3-70-g09d2 From e1781538cf5c870ab696e9b8f0a5c498d3900f2f Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Thu, 17 Dec 2009 13:16:30 +0100 Subject: sched: Assert task state bits at build time Since everybody is lazy and prone to forgetting things, make the compiler help us a bit. Signed-off-by: Peter Zijlstra LKML-Reference: <20091217121830.060186433@chello.nl> Signed-off-by: Ingo Molnar --- fs/proc/array.c | 18 ++++++++++-------- include/linux/sched.h | 4 ++++ 2 files changed, 14 insertions(+), 8 deletions(-) (limited to 'fs/proc/array.c') diff --git a/fs/proc/array.c b/fs/proc/array.c index 96361e8fa3a..f560325c444 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -134,14 +134,14 @@ static inline void task_name(struct seq_file *m, struct task_struct *p) * simple bit tests. */ static const char *task_state_array[] = { - "R (running)", /* 0 */ - "S (sleeping)", /* 1 */ - "D (disk sleep)", /* 2 */ - "T (stopped)", /* 4 */ - "t (tracing stop)", /* 8 */ - "Z (zombie)", /* 16 */ - "X (dead)", /* 32 */ - "x (dead)", /* 64 */ + "R (running)", /* 0 */ + "S (sleeping)", /* 1 */ + "D (disk sleep)", /* 2 */ + "T (stopped)", /* 4 */ + "t (tracing stop)", /* 8 */ + "Z (zombie)", /* 16 */ + "X (dead)", /* 32 */ + "x (dead)", /* 64 */ "K (wakekill)", /* 128 */ "W (waking)", /* 256 */ }; @@ -151,6 +151,8 @@ static inline const char *get_task_state(struct task_struct *tsk) unsigned int state = (tsk->state & TASK_REPORT) | tsk->exit_state; const char **p = &task_state_array[0]; + BUILD_BUG_ON(1 + ilog2(TASK_STATE_MAX) != ARRAY_SIZE(task_state_array)); + while (state) { p++; state >>= 1; diff --git a/include/linux/sched.h b/include/linux/sched.h index 94858df38a8..37543876ddf 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -192,9 +192,13 @@ print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) #define TASK_DEAD 64 #define TASK_WAKEKILL 128 #define TASK_WAKING 256 +#define TASK_STATE_MAX 512 #define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW" +extern char ___assert_task_state[1 - 2*!!( + sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; + /* Convenience macros for the sake of set_task_state */ #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) -- cgit v1.2.3-70-g09d2 From 1306d603fcf1f6682f8575d1ff23631a24184b21 Mon Sep 17 00:00:00 2001 From: KOSAKI Motohiro Date: Fri, 8 Jan 2010 14:42:56 -0800 Subject: proc: partially revert "procfs: provide stack information for threads" Commit d899bf7b (procfs: provide stack information for threads) introduced to show stack information in /proc/{pid}/status. But it cause large performance regression. Unfortunately /proc/{pid}/status is used ps command too and ps is one of most important component. Because both to take mmap_sem and page table walk are heavily operation. If many process run, the ps performance is, [before d899bf7b] % perf stat ps >/dev/null Performance counter stats for 'ps': 4090.435806 task-clock-msecs # 0.032 CPUs 229 context-switches # 0.000 M/sec 0 CPU-migrations # 0.000 M/sec 234 page-faults # 0.000 M/sec 8587565207 cycles # 2099.425 M/sec 9866662403 instructions # 1.149 IPC 3789415411 cache-references # 926.409 M/sec 30419509 cache-misses # 7.437 M/sec 128.859521955 seconds time elapsed [after d899bf7b] % perf stat ps > /dev/null Performance counter stats for 'ps': 4305.081146 task-clock-msecs # 0.028 CPUs 480 context-switches # 0.000 M/sec 2 CPU-migrations # 0.000 M/sec 237 page-faults # 0.000 M/sec 9021211334 cycles # 2095.480 M/sec 10605887536 instructions # 1.176 IPC 3612650999 cache-references # 839.160 M/sec 23917502 cache-misses # 5.556 M/sec 152.277819582 seconds time elapsed Thus, this patch revert it. Fortunately /proc/{pid}/task/{tid}/smaps provide almost same information. we can use it. Commit d899bf7b introduced two features: 1) Add the annotattion of [thread stack: xxxx] mark to /proc/{pid}/task/{tid}/maps. 2) Add StackUsage field to /proc/{pid}/status. I only revert (2), because I haven't seen (1) cause regression. Signed-off-by: KOSAKI Motohiro Cc: Stefani Seibold Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Alexey Dobriyan Cc: "Eric W. Biederman" Cc: Randy Dunlap Cc: Andrew Morton Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/proc.txt | 2 - fs/proc/array.c | 89 -------------------------------------- 2 files changed, 91 deletions(-) (limited to 'fs/proc/array.c') diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 220cc6376ef..0d07513a67a 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -177,7 +177,6 @@ read the file /proc/PID/status: CapBnd: ffffffffffffffff voluntary_ctxt_switches: 0 nonvoluntary_ctxt_switches: 1 - Stack usage: 12 kB This shows you nearly the same information you would get if you viewed it with the ps command. In fact, ps uses the proc file system to obtain its @@ -231,7 +230,6 @@ Table 1-2: Contents of the statm files (as of 2.6.30-rc7) Mems_allowed_list Same as previous, but in "list format" voluntary_ctxt_switches number of voluntary context switches nonvoluntary_ctxt_switches number of non voluntary context switches - Stack usage: stack usage high water mark (round up to page size) .............................................................................. Table 1-3: Contents of the statm files (as of 2.6.8-rc3) diff --git a/fs/proc/array.c b/fs/proc/array.c index f560325c444..13b5d070817 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -327,94 +327,6 @@ static inline void task_context_switch_counts(struct seq_file *m, p->nivcsw); } -#ifdef CONFIG_MMU - -struct stack_stats { - struct vm_area_struct *vma; - unsigned long startpage; - unsigned long usage; -}; - -static int stack_usage_pte_range(pmd_t *pmd, unsigned long addr, - unsigned long end, struct mm_walk *walk) -{ - struct stack_stats *ss = walk->private; - struct vm_area_struct *vma = ss->vma; - pte_t *pte, ptent; - spinlock_t *ptl; - int ret = 0; - - pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); - for (; addr != end; pte++, addr += PAGE_SIZE) { - ptent = *pte; - -#ifdef CONFIG_STACK_GROWSUP - if (pte_present(ptent) || is_swap_pte(ptent)) - ss->usage = addr - ss->startpage + PAGE_SIZE; -#else - if (pte_present(ptent) || is_swap_pte(ptent)) { - ss->usage = ss->startpage - addr + PAGE_SIZE; - pte++; - ret = 1; - break; - } -#endif - } - pte_unmap_unlock(pte - 1, ptl); - cond_resched(); - return ret; -} - -static inline unsigned long get_stack_usage_in_bytes(struct vm_area_struct *vma, - struct task_struct *task) -{ - struct stack_stats ss; - struct mm_walk stack_walk = { - .pmd_entry = stack_usage_pte_range, - .mm = vma->vm_mm, - .private = &ss, - }; - - if (!vma->vm_mm || is_vm_hugetlb_page(vma)) - return 0; - - ss.vma = vma; - ss.startpage = task->stack_start & PAGE_MASK; - ss.usage = 0; - -#ifdef CONFIG_STACK_GROWSUP - walk_page_range(KSTK_ESP(task) & PAGE_MASK, vma->vm_end, - &stack_walk); -#else - walk_page_range(vma->vm_start, (KSTK_ESP(task) & PAGE_MASK) + PAGE_SIZE, - &stack_walk); -#endif - return ss.usage; -} - -static inline void task_show_stack_usage(struct seq_file *m, - struct task_struct *task) -{ - struct vm_area_struct *vma; - struct mm_struct *mm = get_task_mm(task); - - if (mm) { - down_read(&mm->mmap_sem); - vma = find_vma(mm, task->stack_start); - if (vma) - seq_printf(m, "Stack usage:\t%lu kB\n", - get_stack_usage_in_bytes(vma, task) >> 10); - - up_read(&mm->mmap_sem); - mmput(mm); - } -} -#else -static void task_show_stack_usage(struct seq_file *m, struct task_struct *task) -{ -} -#endif /* CONFIG_MMU */ - static void task_cpus_allowed(struct seq_file *m, struct task_struct *task) { seq_printf(m, "Cpus_allowed:\t"); @@ -445,7 +357,6 @@ int proc_pid_status(struct seq_file *m, struct pid_namespace *ns, task_show_regs(m, task); #endif task_context_switch_counts(m, task); - task_show_stack_usage(m, task); return 0; } -- cgit v1.2.3-70-g09d2