diff options
Diffstat (limited to 'kernel/pid.c')
| -rw-r--r-- | kernel/pid.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/kernel/pid.c b/kernel/pid.c index 8387e8c68193..ed89a732432c 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -145,6 +145,23 @@ static int alloc_pidmap(void) return -1; } +static int next_pidmap(int last) +{ + int offset; + pidmap_t *map; + + offset = (last + 1) & BITS_PER_PAGE_MASK; + map = &pidmap_array[(last + 1)/BITS_PER_PAGE]; + for (; map < &pidmap_array[PIDMAP_ENTRIES]; map++, offset = 0) { + if (unlikely(!map->page)) + continue; + offset = find_next_bit((map)->page, BITS_PER_PAGE, offset); + if (offset < BITS_PER_PAGE) + return mk_pid(map, offset); + } + return -1; +} + fastcall void put_pid(struct pid *pid) { if (!pid) @@ -303,6 +320,25 @@ struct pid *find_get_pid(pid_t nr) } /* + * Used by proc to find the first pid that is greater then or equal to nr. + * + * If there is a pid at nr this function is exactly the same as find_pid. + */ +struct pid *find_ge_pid(int nr) +{ + struct pid *pid; + + do { + pid = find_pid(nr); + if (pid) + break; + nr = next_pidmap(nr); + } while (nr > 0); + + return pid; +} + +/* * The pid hash table is scaled according to the amount of memory in the * machine. From a minimum of 16 slots up to 4096 slots at one gigabyte or * more. |