diff options
| -rw-r--r-- | include/linux/threads.h | 9 | ||||
| -rw-r--r-- | kernel/pid.c | 7 |
2 files changed, 16 insertions, 0 deletions
diff --git a/include/linux/threads.h b/include/linux/threads.h index 052b12bec8bd..383ab9592bec 100644 --- a/include/linux/threads.h +++ b/include/linux/threads.h @@ -33,4 +33,13 @@ #define PID_MAX_LIMIT (CONFIG_BASE_SMALL ? PAGE_SIZE * 8 : \ (sizeof(long) > 4 ? 4 * 1024 * 1024 : PID_MAX_DEFAULT)) +/* + * Define a minimum number of pids per cpu. Heuristically based + * on original pid max of 32k for 32 cpus. Also, increase the + * minimum settable value for pid_max on the running system based + * on similar defaults. See kernel/pid.c:pidmap_init() for details. + */ +#define PIDS_PER_CPU_DEFAULT 1024 +#define PIDS_PER_CPU_MIN 8 + #endif diff --git a/kernel/pid.c b/kernel/pid.c index aebb30d9c233..e9fd8c132d26 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -513,6 +513,13 @@ void __init pidhash_init(void) void __init pidmap_init(void) { + /* bump default and minimum pid_max based on number of cpus */ + pid_max = min(pid_max_max, max_t(int, pid_max, + PIDS_PER_CPU_DEFAULT * num_possible_cpus())); + pid_max_min = max_t(int, pid_max_min, + PIDS_PER_CPU_MIN * num_possible_cpus()); + pr_info("pid_max: default: %u minimum: %u\n", pid_max, pid_max_min); + init_pid_ns.pidmap[0].page = kzalloc(PAGE_SIZE, GFP_KERNEL); /* Reserve PID 0. We never call free_pidmap(0) */ set_bit(0, init_pid_ns.pidmap[0].page); |