1 Index: linux-stage/fs/ext4/mballoc.c
2 ===================================================================
3 --- linux-stage.orig/fs/ext4/mballoc.c
4 +++ linux-stage/fs/ext4/mballoc.c
5 @@ -2078,6 +2078,21 @@ static int ext4_mb_good_group(struct ext
9 +static u64 available_blocks_count(struct ext4_sb_info *sbi)
11 + ext4_fsblk_t resv_blocks;
13 + struct ext4_super_block *es = sbi->s_es;
15 + resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
16 + bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
17 + percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
19 + bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
20 + return bfree - (ext4_r_blocks_count(es) + resv_blocks);
24 static noinline_for_stack int
25 ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
27 @@ -2087,6 +2102,7 @@ ext4_mb_regular_allocator(struct ext4_al
28 struct ext4_sb_info *sbi;
29 struct super_block *sb;
30 struct ext4_buddy e4b;
31 + ext4_fsblk_t avail_blocks;
35 @@ -2136,6 +2152,21 @@ ext4_mb_regular_allocator(struct ext4_al
37 /* Let's just scan groups to find more-less suitable blocks */
38 cr = ac->ac_2order ? 0 : 1;
40 + /* Choose what loop to pass based on disk fullness */
41 + avail_blocks = available_blocks_count(sbi) ;
43 + if (avail_blocks < sbi->s_mb_c3_blocks) {
45 + atomic64_inc(&sbi->s_bal_cX_skipped[2]);
46 + } else if(avail_blocks < sbi->s_mb_c2_blocks) {
48 + atomic64_inc(&sbi->s_bal_cX_skipped[1]);
49 + } else if(avail_blocks < sbi->s_mb_c1_blocks) {
51 + atomic64_inc(&sbi->s_bal_cX_skipped[0]);
55 * cr == 0 try to get exact allocation,
56 * cr == 3 try to get anything
57 @@ -2193,6 +2224,9 @@ repeat:
58 if (ac->ac_status != AC_STATUS_CONTINUE)
61 + /* Processed all groups and haven't found blocks */
63 + atomic64_inc(&sbi->s_bal_cX_failed[cr]);
66 if (ac->ac_b_ex.fe_len > 0 && ac->ac_status != AC_STATUS_FOUND &&
67 @@ -2316,6 +2350,93 @@ static const struct seq_operations ext4_
68 .show = ext4_mb_seq_groups_show,
71 +static int mb_seq_alloc_show(struct seq_file *seq, void *v)
73 + struct super_block *sb = seq->private;
74 + struct ext4_sb_info *sbi = EXT4_SB(sb);
76 + seq_printf(seq, "mballoc:\n");
77 + seq_printf(seq, "\tblocks: %u\n", atomic_read(&sbi->s_bal_allocated));
78 + seq_printf(seq, "\treqs: %u\n", atomic_read(&sbi->s_bal_reqs));
79 + seq_printf(seq, "\tsuccess: %u\n", atomic_read(&sbi->s_bal_success));
81 + seq_printf(seq, "\textents_scanned: %u\n",
82 + atomic_read(&sbi->s_bal_ex_scanned));
83 + seq_printf(seq, "\t\tgoal_hits: %u\n", atomic_read(&sbi->s_bal_goals));
84 + seq_printf(seq, "\t\t2^n_hits: %u\n", atomic_read(&sbi->s_bal_2orders));
85 + seq_printf(seq, "\t\tbreaks: %u\n", atomic_read(&sbi->s_bal_breaks));
86 + seq_printf(seq, "\t\tlost: %u\n", atomic_read(&sbi->s_mb_lost_chunks));
88 + seq_printf(seq, "\tuseless_c1_loops: %lu\n",
89 + atomic64_read(&sbi->s_bal_cX_failed[0]));
90 + seq_printf(seq, "\tuseless_c2_loops: %lu\n",
91 + atomic64_read(&sbi->s_bal_cX_failed[1]));
92 + seq_printf(seq, "\tuseless_c3_loops: %lu\n",
93 + atomic64_read(&sbi->s_bal_cX_failed[2]));
94 + seq_printf(seq, "\tskipped_c1_loops: %lu\n",
95 + atomic64_read(&sbi->s_bal_cX_skipped[0]));
96 + seq_printf(seq, "\tskipped_c2_loops: %lu\n",
97 + atomic64_read(&sbi->s_bal_cX_skipped[1]));
98 + seq_printf(seq, "\tskipped_c3_loops: %lu\n",
99 + atomic64_read(&sbi->s_bal_cX_skipped[2]));
100 + seq_printf(seq, "\tbuddies_generated: %lu\n",
101 + sbi->s_mb_buddies_generated);
102 + seq_printf(seq, "\tbuddies_time_used: %llu\n", sbi->s_mb_generation_time);
103 + seq_printf(seq, "\tpreallocated: %u\n",
104 + atomic_read(&sbi->s_mb_preallocated));
105 + seq_printf(seq, "\tdiscarded: %u\n",
106 + atomic_read(&sbi->s_mb_discarded));
110 +static ssize_t mb_seq_alloc_write(struct file *file,
111 + const char __user *buf,
112 + size_t cnt, loff_t *pos)
114 + struct ext4_sb_info *sbi = EXT4_SB(PDE_DATA(file_inode(file)));
116 + atomic_set(&sbi->s_bal_allocated, 0),
117 + atomic_set(&sbi->s_bal_reqs, 0),
118 + atomic_set(&sbi->s_bal_success, 0);
120 + atomic_set(&sbi->s_bal_ex_scanned, 0),
121 + atomic_set(&sbi->s_bal_goals, 0),
122 + atomic_set(&sbi->s_bal_2orders, 0),
123 + atomic_set(&sbi->s_bal_breaks, 0),
124 + atomic_set(&sbi->s_mb_lost_chunks, 0);
126 + atomic64_set(&sbi->s_bal_cX_failed[0], 0),
127 + atomic64_set(&sbi->s_bal_cX_failed[1], 0),
128 + atomic64_set(&sbi->s_bal_cX_failed[2], 0);
130 + atomic64_set(&sbi->s_bal_cX_skipped[0], 0),
131 + atomic64_set(&sbi->s_bal_cX_skipped[1], 0),
132 + atomic64_set(&sbi->s_bal_cX_skipped[2], 0);
135 + sbi->s_mb_buddies_generated = 0;
136 + sbi->s_mb_generation_time = 0;
138 + atomic_set(&sbi->s_mb_preallocated, 0),
139 + atomic_set(&sbi->s_mb_discarded, 0);
144 +static int mb_seq_alloc_open(struct inode *inode, struct file *file)
146 + return single_open(file, mb_seq_alloc_show, PDE_DATA(inode));
149 +static const struct file_operations ext4_mb_seq_alloc_fops = {
150 + .owner = THIS_MODULE,
151 + .open = mb_seq_alloc_open,
153 + .llseek = seq_lseek,
154 + .release = single_release,
155 + .write = mb_seq_alloc_write,
158 #define EXT4_MB_PREALLOC_TABLE "prealloc_table"
160 static int ext4_mb_check_and_update_prealloc(struct ext4_sb_info *sbi,
161 @@ -2730,6 +2851,7 @@ static int ext4_groupinfo_create_slab(si
165 +#define THRESHOLD_BLOCKS(ts) (ext4_blocks_count(sbi->s_es) / 100 * ts)
166 int ext4_mb_init(struct super_block *sb)
168 struct ext4_sb_info *sbi = EXT4_SB(sb);
169 @@ -2781,6 +2903,9 @@ int ext4_mb_init(struct super_block *sb)
170 sbi->s_mb_min_to_scan = MB_DEFAULT_MIN_TO_SCAN;
171 sbi->s_mb_stats = MB_DEFAULT_STATS;
172 sbi->s_mb_order2_reqs = MB_DEFAULT_ORDER2_REQS;
173 + sbi->s_mb_c1_blocks = THRESHOLD_BLOCKS(MB_DEFAULT_C1_THRESHOLD);
174 + sbi->s_mb_c2_blocks = THRESHOLD_BLOCKS(MB_DEFAULT_C2_THRESHOLD);
175 + sbi->s_mb_c3_blocks = THRESHOLD_BLOCKS(MB_DEFAULT_C3_THRESHOLD);
177 * The default group preallocation is 512, which for 4k block
178 * sizes translates to 2 megabytes. However for bigalloc file
179 @@ -2853,6 +2978,8 @@ int ext4_mb_init(struct super_block *sb)
180 proc_create_data(EXT4_MB_PREALLOC_TABLE, S_IFREG | S_IRUGO |
181 S_IWUSR, sbi->s_proc,
182 &ext4_mb_prealloc_seq_fops, sb);
183 + proc_create_data("mb_alloc_stats", S_IFREG | S_IRUGO | S_IWUSR,
184 + sbi->s_proc, &ext4_mb_seq_alloc_fops, sb);
185 proc_create_data("mb_last_group", S_IFREG | S_IRUGO |
186 S_IWUSR, sbi->s_proc,
187 &ext4_mb_seq_last_group_fops, sb);
188 @@ -2906,6 +3033,7 @@ int ext4_mb_release(struct super_block *
189 remove_proc_entry("mb_last_group", sbi->s_proc);
190 remove_proc_entry("mb_last_start", sbi->s_proc);
191 remove_proc_entry(EXT4_MB_PREALLOC_TABLE, sbi->s_proc);
192 + remove_proc_entry("mb_alloc_stats", sbi->s_proc);
195 if (sbi->s_group_info) {
196 @@ -2936,6 +3064,16 @@ int ext4_mb_release(struct super_block *
197 atomic_read(&sbi->s_bal_reqs),
198 atomic_read(&sbi->s_bal_success));
199 ext4_msg(sb, KERN_INFO,
200 + "mballoc: (%lu, %lu, %lu) useless c(0,1,2) loops",
201 + atomic64_read(&sbi->s_bal_cX_failed[0]),
202 + atomic64_read(&sbi->s_bal_cX_failed[1]),
203 + atomic64_read(&sbi->s_bal_cX_failed[2]));
204 + ext4_msg(sb, KERN_INFO,
205 + "mballoc: (%lu, %lu, %lu) skipped c(0,1,2) loops",
206 + atomic64_read(&sbi->s_bal_cX_skipped[0]),
207 + atomic64_read(&sbi->s_bal_cX_skipped[1]),
208 + atomic64_read(&sbi->s_bal_cX_skipped[2]));
209 + ext4_msg(sb, KERN_INFO,
210 "mballoc: %u extents scanned, %u goal hits, "
211 "%u 2^N hits, %u breaks, %u lost",
212 atomic_read(&sbi->s_bal_ex_scanned),
213 Index: linux-stage/fs/ext4/ext4.h
214 ===================================================================
215 --- linux-stage.orig/fs/ext4/ext4.h
216 +++ linux-stage/fs/ext4/ext4.h
217 @@ -1409,6 +1409,9 @@ struct ext4_sb_info {
218 unsigned int s_mb_min_to_scan;
219 unsigned int s_mb_stats;
220 unsigned int s_mb_order2_reqs;
221 + ext4_fsblk_t s_mb_c1_blocks;
222 + ext4_fsblk_t s_mb_c2_blocks;
223 + ext4_fsblk_t s_mb_c3_blocks;
224 unsigned long *s_mb_prealloc_table;
225 unsigned int s_mb_group_prealloc;
226 unsigned int s_max_dir_size_kb;
227 @@ -1425,6 +1428,9 @@ struct ext4_sb_info {
228 atomic_t s_bal_goals; /* goal hits */
229 atomic_t s_bal_breaks; /* too long searches */
230 atomic_t s_bal_2orders; /* 2^order hits */
231 + /* cX loop didn't find blocks */
232 + atomic64_t s_bal_cX_failed[3];
233 + atomic64_t s_bal_cX_skipped[3];
234 spinlock_t s_bal_lock;
235 unsigned long s_mb_buddies_generated;
236 unsigned long long s_mb_generation_time;
237 Index: linux-stage/fs/ext4/super.c
238 ===================================================================
239 --- linux-stage.orig/fs/ext4/super.c
240 +++ linux-stage/fs/ext4/super.c
241 @@ -2734,6 +2734,73 @@ static ssize_t sbi_deprecated_show(struc
242 return snprintf(buf, PAGE_SIZE, "%d\n", a->u.deprecated_val);
245 +static int save_threshold(struct ext4_sb_info *sbi, const char *buf,
246 + ext4_fsblk_t *blocks) {
247 + unsigned long long val;
249 + if (!parse_strtoull(buf, 100, &val)) {
250 + *blocks = val * ext4_blocks_count(sbi->s_es) / 100;
257 +#define THRESHOLD_PERCENT(ts) (ts * 100 / ext4_blocks_count(sbi->s_es))
258 +static ssize_t mb_c1_threshold_store(struct ext4_attr *a,
259 + struct ext4_sb_info *sbi,
260 + const char *buf, size_t count)
264 + ret = save_threshold(sbi, buf, &sbi->s_mb_c1_blocks);
266 + return ret ? ret : count;
269 +static ssize_t mb_c1_threshold_show(struct ext4_attr *a,
270 + struct ext4_sb_info *sbi, char *buf)
272 + return snprintf(buf, PAGE_SIZE, "%llu\n",
273 + THRESHOLD_PERCENT(sbi->s_mb_c1_blocks));
276 +static ssize_t mb_c2_threshold_store(struct ext4_attr *a,
277 + struct ext4_sb_info *sbi,
278 + const char *buf, size_t count)
282 + ret = save_threshold(sbi, buf, &sbi->s_mb_c2_blocks);
283 + return ret ? ret : count;
286 +static ssize_t mb_c2_threshold_show(struct ext4_attr *a,
287 + struct ext4_sb_info *sbi, char *buf)
289 + return snprintf(buf, PAGE_SIZE, "%llu\n",
290 + THRESHOLD_PERCENT(sbi->s_mb_c2_blocks));
293 +static ssize_t mb_c3_threshold_store(struct ext4_attr *a,
294 + struct ext4_sb_info *sbi,
295 + const char *buf, size_t count)
299 + ret = save_threshold(sbi, buf, &sbi->s_mb_c3_blocks);
301 + return ret ? ret : count;
304 +static ssize_t mb_c3_threshold_show(struct ext4_attr *a,
305 + struct ext4_sb_info *sbi, char *buf)
307 + return snprintf(buf, PAGE_SIZE, "%llu\n",
308 + THRESHOLD_PERCENT(sbi->s_mb_c3_blocks));
312 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
313 static struct ext4_attr ext4_attr_##_name = { \
314 .attr = {.name = __stringify(_name), .mode = _mode }, \
315 @@ -2790,6 +2857,9 @@ EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats
316 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
317 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
318 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
319 +EXT4_RW_ATTR(mb_c1_threshold);
320 +EXT4_RW_ATTR(mb_c2_threshold);
321 +EXT4_RW_ATTR(mb_c3_threshold);
322 EXT4_RW_ATTR_SBI_UI(mb_small_req, s_mb_small_req);
323 EXT4_RW_ATTR_SBI_UI(mb_large_req, s_mb_large_req);
324 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
325 @@ -2820,6 +2890,9 @@ static struct attribute *ext4_attrs[] =
326 ATTR_LIST(mb_max_to_scan),
327 ATTR_LIST(mb_min_to_scan),
328 ATTR_LIST(mb_order2_req),
329 + ATTR_LIST(mb_c1_threshold),
330 + ATTR_LIST(mb_c2_threshold),
331 + ATTR_LIST(mb_c3_threshold),
332 ATTR_LIST(mb_small_req),
333 ATTR_LIST(mb_large_req),
334 ATTR_LIST(mb_group_prealloc),
335 Index: linux-stage/fs/ext4/mballoc.h
336 ===================================================================
337 --- linux-stage.orig/fs/ext4/mballoc.h
338 +++ linux-stage/fs/ext4/mballoc.h
339 @@ -84,6 +84,9 @@ extern ushort ext4_mballoc_debug;
340 * for which requests use 2^N search using buddies
342 #define MB_DEFAULT_ORDER2_REQS 8
343 +#define MB_DEFAULT_C1_THRESHOLD 25
344 +#define MB_DEFAULT_C2_THRESHOLD 15
345 +#define MB_DEFAULT_C3_THRESHOLD 5
348 * default group prealloc size 512 blocks