diff options
Diffstat (limited to 'mm/page_alloc.c')
| -rw-r--r-- | mm/page_alloc.c | 28 |
1 files changed, 20 insertions, 8 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 083cbcb5bdde..12fac9084c48 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6853,8 +6853,8 @@ static int sysctl_min_slab_ratio_sysctl_handler(const struct ctl_table *table, i /* * lowmem_reserve_ratio_sysctl_handler - just a wrapper around - * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve() - * whenever sysctl_lowmem_reserve_ratio changes. + * proc_dointvec_minmax() so that we can call + * setup_per_zone_lowmem_reserve() when the sysctl is written. * * The reserve ratio obviously has absolutely no relation with the * minimum watermarks. The lowmem reserve ratio can only make sense @@ -6863,16 +6863,27 @@ static int sysctl_min_slab_ratio_sysctl_handler(const struct ctl_table *table, i static int lowmem_reserve_ratio_sysctl_handler(const struct ctl_table *table, int write, void *buffer, size_t *length, loff_t *ppos) { - int i; + struct ctl_table tmp = *table; + int ratio[ARRAY_SIZE(sysctl_lowmem_reserve_ratio)]; + int rc; - proc_dointvec_minmax(table, write, buffer, length, ppos); + if (!write) + return proc_dointvec_minmax(table, write, buffer, length, ppos); - for (i = 0; i < MAX_NR_ZONES; i++) { - if (sysctl_lowmem_reserve_ratio[i] < 1) - sysctl_lowmem_reserve_ratio[i] = 0; - } + /* + * proc_dointvec_max() works incrementally. Use a buffer and only set + * the values if all of them parse cleanly. + */ + memcpy(ratio, sysctl_lowmem_reserve_ratio, sizeof(ratio)); + tmp.data = ratio; + + rc = proc_dointvec_minmax(&tmp, write, buffer, length, ppos); + if (rc) + return rc; + memcpy(sysctl_lowmem_reserve_ratio, ratio, sizeof(ratio)); setup_per_zone_lowmem_reserve(); + return 0; } @@ -6971,6 +6982,7 @@ static const struct ctl_table page_alloc_sysctl_table[] = { .maxlen = sizeof(sysctl_lowmem_reserve_ratio), .mode = 0644, .proc_handler = lowmem_reserve_ratio_sysctl_handler, + .extra1 = SYSCTL_ZERO, }, #ifdef CONFIG_NUMA { |