[mirror_ubuntu-bionic-kernel.git] / include / linux / threads.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_THREADS_H
#define _LINUX_THREADS_H


/*
 * The default limit for the nr of threads is now in
 * /proc/sys/kernel/threads-max.
 */

/*
 * Maximum supported processors.  Setting this smaller saves quite a
 * bit of memory.  Use nr_cpu_ids instead of this except for static bitmaps.
 */
#ifndef CONFIG_NR_CPUS
/* FIXME: This should be fixed in the arch's Kconfig */
#define CONFIG_NR_CPUS	1
#endif

/* Places which use this should consider cpumask_var_t. */
#define NR_CPUS		CONFIG_NR_CPUS

#define MIN_THREADS_LEFT_FOR_ROOT 4

/*
 * This controls the default maximum pid allocated to a process
 */
#define PID_MAX_DEFAULT (CONFIG_BASE_SMALL ? 0x1000 : 0x8000)

/*
 * A maximum of 4 million PIDs should be enough for a while.
 * [NOTE: PID/TIDs are limited to 2^29 ~= 500+ million, see futex.h.]
 */
#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
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
1da177e4 LT	2	#ifndef _LINUX_THREADS_H
	3	#define _LINUX_THREADS_H
	4
1da177e4 LT	5
	6	/*
	7	* The default limit for the nr of threads is now in
	8	* /proc/sys/kernel/threads-max.
	9	*/
	10
	11	/*
278d1ed6 RR	12	* Maximum supported processors. Setting this smaller saves quite a
278d1ed6 RR	13	* bit of memory. Use nr_cpu_ids instead of this except for static bitmaps.
1da177e4	14	*/
278d1ed6 RR	15	#ifndef CONFIG_NR_CPUS
	16	/* FIXME: This should be fixed in the arch's Kconfig */
	17	#define CONFIG_NR_CPUS 1
1da177e4 LT	18	#endif
1da177e4 LT	19
278d1ed6 RR	20	/* Places which use this should consider cpumask_var_t. */
	21	#define NR_CPUS CONFIG_NR_CPUS
	22
1da177e4 LT	23	#define MIN_THREADS_LEFT_FOR_ROOT 4
	24
	25	/*
	26	* This controls the default maximum pid allocated to a process
	27	*/
	28	#define PID_MAX_DEFAULT (CONFIG_BASE_SMALL ? 0x1000 : 0x8000)
	29
	30	/*
0771dfef IM	31	* A maximum of 4 million PIDs should be enough for a while.
0771dfef IM	32	* [NOTE: PID/TIDs are limited to 2^29 ~= 500+ million, see futex.h.]
1da177e4 LT	33	*/
	34	#define PID_MAX_LIMIT (CONFIG_BASE_SMALL ? PAGE_SIZE * 8 : \
	35	(sizeof(long) > 4 ? 4 * 1024 * 1024 : PID_MAX_DEFAULT))
	36
72680a19 HB	37	/*
	38	* Define a minimum number of pids per cpu. Heuristically based
	39	* on original pid max of 32k for 32 cpus. Also, increase the
	40	* minimum settable value for pid_max on the running system based
	41	* on similar defaults. See kernel/pid.c:pidmap_init() for details.
	42	*/
	43	#define PIDS_PER_CPU_DEFAULT 1024
	44	#define PIDS_PER_CPU_MIN 8
	45
1da177e4	46	#endif