diff --git a/kernel/fork.c b/kernel/fork.c index 01038e6f51a8d026dbc108c360b627af1fb55a9d..c7f2e1a4187ae4aa5436b8e384838ee28edcd4eb 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -87,6 +87,16 @@ #define CREATE_TRACE_POINTS #include +/* + * Minimum number of threads to boot the kernel + */ +#define MIN_THREADS 20 + +/* + * Maximum number of threads + */ +#define MAX_THREADS FUTEX_TID_MASK + /* * Protected counters by write_lock_irq(&tasklist_lock) */ @@ -258,18 +268,19 @@ void __init __weak arch_task_cache_init(void) { } */ static void set_max_threads(void) { - /* - * The default maximum number of threads is set to a safe - * value: the thread structures can take up at most one - * eighth of the memory. - */ - max_threads = totalram_pages / (8 * THREAD_SIZE / PAGE_SIZE); + u64 threads; /* - * we need to allow at least 20 threads to boot a system + * The number of threads shall be limited such that the thread + * structures may only consume a small part of the available memory. */ - if (max_threads < 20) - max_threads = 20; + if (fls64(totalram_pages) + fls64(PAGE_SIZE) > 64) + threads = MAX_THREADS; + else + threads = div64_u64((u64) totalram_pages * (u64) PAGE_SIZE, + (u64) THREAD_SIZE * 8UL); + + max_threads = clamp_t(u64, threads, MIN_THREADS, MAX_THREADS); } void __init fork_init(void)