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-rw-r--r--Documentation/sysctl/vm.txt28
-rw-r--r--include/linux/writeback.h2
-rw-r--r--kernel/sysctl.c23
-rw-r--r--mm/pdflush.c31
4 files changed, 12 insertions, 72 deletions
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index b716d33912d8..c302ddf629a0 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -39,8 +39,6 @@ Currently, these files are in /proc/sys/vm:
39- nr_hugepages 39- nr_hugepages
40- nr_overcommit_hugepages 40- nr_overcommit_hugepages
41- nr_pdflush_threads 41- nr_pdflush_threads
42- nr_pdflush_threads_min
43- nr_pdflush_threads_max
44- nr_trim_pages (only if CONFIG_MMU=n) 42- nr_trim_pages (only if CONFIG_MMU=n)
45- numa_zonelist_order 43- numa_zonelist_order
46- oom_dump_tasks 44- oom_dump_tasks
@@ -469,32 +467,6 @@ The default value is 0.
469 467
470============================================================== 468==============================================================
471 469
472nr_pdflush_threads_min
473
474This value controls the minimum number of pdflush threads.
475
476At boot time, the kernel will create and maintain 'nr_pdflush_threads_min'
477threads for the kernel's lifetime.
478
479The default value is 2. The minimum value you can specify is 1, and
480the maximum value is the current setting of 'nr_pdflush_threads_max'.
481
482See 'nr_pdflush_threads_max' below for more information.
483
484==============================================================
485
486nr_pdflush_threads_max
487
488This value controls the maximum number of pdflush threads that can be
489created. The pdflush algorithm will create a new pdflush thread (up to
490this maximum) if no pdflush threads have been available for >= 1 second.
491
492The default value is 8. The minimum value you can specify is the
493current value of 'nr_pdflush_threads_min' and the
494maximum is 1000.
495
496==============================================================
497
498overcommit_memory: 470overcommit_memory:
499 471
500This value contains a flag that enables memory overcommitment. 472This value contains a flag that enables memory overcommitment.
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index 9c1ed1fb6ddb..93445477f86a 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -168,8 +168,6 @@ void writeback_set_ratelimit(void);
168/* pdflush.c */ 168/* pdflush.c */
169extern int nr_pdflush_threads; /* Global so it can be exported to sysctl 169extern int nr_pdflush_threads; /* Global so it can be exported to sysctl
170 read-only. */ 170 read-only. */
171extern int nr_pdflush_threads_max; /* Global so it can be exported to sysctl */
172extern int nr_pdflush_threads_min; /* Global so it can be exported to sysctl */
173 171
174 172
175#endif /* WRITEBACK_H */ 173#endif /* WRITEBACK_H */
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index ea78fa101ad6..b2970d56fb76 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -101,7 +101,6 @@ static int __maybe_unused one = 1;
101static int __maybe_unused two = 2; 101static int __maybe_unused two = 2;
102static unsigned long one_ul = 1; 102static unsigned long one_ul = 1;
103static int one_hundred = 100; 103static int one_hundred = 100;
104static int one_thousand = 1000;
105 104
106/* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */ 105/* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
107static unsigned long dirty_bytes_min = 2 * PAGE_SIZE; 106static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
@@ -1034,28 +1033,6 @@ static struct ctl_table vm_table[] = {
1034 .proc_handler = &proc_dointvec, 1033 .proc_handler = &proc_dointvec,
1035 }, 1034 },
1036 { 1035 {
1037 .ctl_name = CTL_UNNUMBERED,
1038 .procname = "nr_pdflush_threads_min",
1039 .data = &nr_pdflush_threads_min,
1040 .maxlen = sizeof nr_pdflush_threads_min,
1041 .mode = 0644 /* read-write */,
1042 .proc_handler = &proc_dointvec_minmax,
1043 .strategy = &sysctl_intvec,
1044 .extra1 = &one,
1045 .extra2 = &nr_pdflush_threads_max,
1046 },
1047 {
1048 .ctl_name = CTL_UNNUMBERED,
1049 .procname = "nr_pdflush_threads_max",
1050 .data = &nr_pdflush_threads_max,
1051 .maxlen = sizeof nr_pdflush_threads_max,
1052 .mode = 0644 /* read-write */,
1053 .proc_handler = &proc_dointvec_minmax,
1054 .strategy = &sysctl_intvec,
1055 .extra1 = &nr_pdflush_threads_min,
1056 .extra2 = &one_thousand,
1057 },
1058 {
1059 .ctl_name = VM_SWAPPINESS, 1036 .ctl_name = VM_SWAPPINESS,
1060 .procname = "swappiness", 1037 .procname = "swappiness",
1061 .data = &vm_swappiness, 1038 .data = &vm_swappiness,
diff --git a/mm/pdflush.c b/mm/pdflush.c
index f2caf96993f8..235ac440c44e 100644
--- a/mm/pdflush.c
+++ b/mm/pdflush.c
@@ -58,14 +58,6 @@ static DEFINE_SPINLOCK(pdflush_lock);
58int nr_pdflush_threads = 0; 58int nr_pdflush_threads = 0;
59 59
60/* 60/*
61 * The max/min number of pdflush threads. R/W by sysctl at
62 * /proc/sys/vm/nr_pdflush_threads_max/min
63 */
64int nr_pdflush_threads_max __read_mostly = MAX_PDFLUSH_THREADS;
65int nr_pdflush_threads_min __read_mostly = MIN_PDFLUSH_THREADS;
66
67
68/*
69 * The time at which the pdflush thread pool last went empty 61 * The time at which the pdflush thread pool last went empty
70 */ 62 */
71static unsigned long last_empty_jifs; 63static unsigned long last_empty_jifs;
@@ -76,7 +68,7 @@ static unsigned long last_empty_jifs;
76 * Thread pool management algorithm: 68 * Thread pool management algorithm:
77 * 69 *
78 * - The minimum and maximum number of pdflush instances are bound 70 * - The minimum and maximum number of pdflush instances are bound
79 * by nr_pdflush_threads_min and nr_pdflush_threads_max. 71 * by MIN_PDFLUSH_THREADS and MAX_PDFLUSH_THREADS.
80 * 72 *
81 * - If there have been no idle pdflush instances for 1 second, create 73 * - If there have been no idle pdflush instances for 1 second, create
82 * a new one. 74 * a new one.
@@ -142,13 +134,14 @@ static int __pdflush(struct pdflush_work *my_work)
142 * To throttle creation, we reset last_empty_jifs. 134 * To throttle creation, we reset last_empty_jifs.
143 */ 135 */
144 if (time_after(jiffies, last_empty_jifs + 1 * HZ)) { 136 if (time_after(jiffies, last_empty_jifs + 1 * HZ)) {
145 if (list_empty(&pdflush_list) && 137 if (list_empty(&pdflush_list)) {
146 nr_pdflush_threads < nr_pdflush_threads_max) { 138 if (nr_pdflush_threads < MAX_PDFLUSH_THREADS) {
147 last_empty_jifs = jiffies; 139 last_empty_jifs = jiffies;
148 nr_pdflush_threads++; 140 nr_pdflush_threads++;
149 spin_unlock_irq(&pdflush_lock); 141 spin_unlock_irq(&pdflush_lock);
150 start_one_pdflush_thread(); 142 start_one_pdflush_thread();
151 spin_lock_irq(&pdflush_lock); 143 spin_lock_irq(&pdflush_lock);
144 }
152 } 145 }
153 } 146 }
154 147
@@ -160,7 +153,7 @@ static int __pdflush(struct pdflush_work *my_work)
160 */ 153 */
161 if (list_empty(&pdflush_list)) 154 if (list_empty(&pdflush_list))
162 continue; 155 continue;
163 if (nr_pdflush_threads <= nr_pdflush_threads_min) 156 if (nr_pdflush_threads <= MIN_PDFLUSH_THREADS)
164 continue; 157 continue;
165 pdf = list_entry(pdflush_list.prev, struct pdflush_work, list); 158 pdf = list_entry(pdflush_list.prev, struct pdflush_work, list);
166 if (time_after(jiffies, pdf->when_i_went_to_sleep + 1 * HZ)) { 159 if (time_after(jiffies, pdf->when_i_went_to_sleep + 1 * HZ)) {
@@ -266,9 +259,9 @@ static int __init pdflush_init(void)
266 * Pre-set nr_pdflush_threads... If we fail to create, 259 * Pre-set nr_pdflush_threads... If we fail to create,
267 * the count will be decremented. 260 * the count will be decremented.
268 */ 261 */
269 nr_pdflush_threads = nr_pdflush_threads_min; 262 nr_pdflush_threads = MIN_PDFLUSH_THREADS;
270 263
271 for (i = 0; i < nr_pdflush_threads_min; i++) 264 for (i = 0; i < MIN_PDFLUSH_THREADS; i++)
272 start_one_pdflush_thread(); 265 start_one_pdflush_thread();
273 return 0; 266 return 0;
274} 267}