diff options
Diffstat (limited to 'usr/src/uts/common/brand/lx/sys/lx_futex.h')
| -rw-r--r-- | usr/src/uts/common/brand/lx/sys/lx_futex.h | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/usr/src/uts/common/brand/lx/sys/lx_futex.h b/usr/src/uts/common/brand/lx/sys/lx_futex.h new file mode 100644 index 0000000000..7eba389218 --- /dev/null +++ b/usr/src/uts/common/brand/lx/sys/lx_futex.h @@ -0,0 +1,143 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License (the "License"). + * You may not use this file except in compliance with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2007 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +/* + * Copyright 2017, Joyent, Inc. + */ + +#ifndef _SYS_LX_FUTEX_H +#define _SYS_LX_FUTEX_H + +#ifdef __cplusplus +extern "C" { +#endif + +#define FUTEX_WAIT 0 +#define FUTEX_WAKE 1 +#define FUTEX_FD 2 +#define FUTEX_REQUEUE 3 +#define FUTEX_CMP_REQUEUE 4 +#define FUTEX_WAKE_OP 5 +#define FUTEX_LOCK_PI 6 +#define FUTEX_UNLOCK_PI 7 +#define FUTEX_TRYLOCK_PI 8 +#define FUTEX_WAIT_BITSET 9 +#define FUTEX_WAKE_BITSET 10 +#define FUTEX_WAIT_REQUEUE_PI 11 +#define FUTEX_CMP_REQUEUE_PI 12 +#define FUTEX_MAX_CMD FUTEX_CMP_REQUEUE_PI + +/* + * Flags that can be OR'd into a futex operation. + */ +#define FUTEX_CMD_MASK 0x007f +#define FUTEX_PRIVATE_FLAG 0x0080 +#define FUTEX_CLOCK_REALTIME 0x0100 + +#define FUTEX_BITSET_MATCH_ANY 0xffffffff +/* + * FUTEX_WAKE_OP operations + */ +#define FUTEX_OP_SET 0 /* *(int *)UADDR2 = OPARG; */ +#define FUTEX_OP_ADD 1 /* *(int *)UADDR2 += OPARG; */ +#define FUTEX_OP_OR 2 /* *(int *)UADDR2 |= OPARG; */ +#define FUTEX_OP_ANDN 3 /* *(int *)UADDR2 &= ~OPARG; */ +#define FUTEX_OP_XOR 4 /* *(int *)UADDR2 ^= OPARG; */ + +/* + * FUTEX_WAKE_OP comparison operations + */ +#define FUTEX_OP_CMP_EQ 0 /* if (oldval == CMPARG) wake */ +#define FUTEX_OP_CMP_NE 1 /* if (oldval != CMPARG) wake */ +#define FUTEX_OP_CMP_LT 2 /* if (oldval < CMPARG) wake */ +#define FUTEX_OP_CMP_LE 3 /* if (oldval <= CMPARG) wake */ +#define FUTEX_OP_CMP_GT 4 /* if (oldval > CMPARG) wake */ +#define FUTEX_OP_CMP_GE 5 /* if (oldval >= CMPARG) wake */ + +/* + * The encoding of the FUTEX_WAKE_OP operation in 32 bits: + * + * +--+-- - --+-- - --+-- - --+-- - --+ + * |S |OP |CMP |OPARG |CMPARG | + * +--+-- - --+-- - --+-- - --+-- - --+ + * |31|30 - 28|27 - 24|23 - 12|11 - 0| + * + * The S bit denotes that the OPARG should be (1 << OPARG) instead of OPARG. + * (Yes, this whole thing is entirely absurd -- see the block comment in + * lx_futex.c for an explanation of this nonsense.) Macros to extract the + * various components from the operation, given the above encoding: + */ +#define FUTEX_OP_OP(x) (((x) >> 28) & 7) +#define FUTEX_OP_CMP(x) (((x) >> 24) & 15) +#define FUTEX_OP_OPARG(x) (((x) >> 31) ? (1 << (((x) << 8) >> 20)) : \ + ((((x) << 8) >> 20))) +#define FUTEX_OP_CMPARG(x) (((x) << 20) >> 20) + +#ifdef _KERNEL + +/* + * This structure is used to track all the threads currently waiting on a + * futex. There is one fwaiter_t for each blocked thread. We store all + * fwaiter_t's in a hash structure, indexed by the memid_t of the integer + * containing the futex's value. + * + * At the moment, all fwaiter_t's for a single futex are simply dumped into + * the hash bucket. If futex contention ever becomes a hot path, we can + * chain a single futex's waiters together. + */ +typedef struct fwaiter { + memid_t fw_memid; /* memid of the user-space futex */ + kcondvar_t fw_cv; /* cond var */ + struct fwaiter *fw_next; /* hash queue */ + struct fwaiter *fw_prev; /* hash queue */ + uint32_t fw_bits; /* bits waiting on */ + pid_t fw_tid; /* for PI futexes; the waiter's tid */ + int fw_opri; /* for PI futexes; original pri. */ + boolean_t fw_pri_up; /* for PI futexes; pri. increased */ + volatile int fw_woken; +} fwaiter_t; + +#define FUTEX_WAITERS 0x80000000 +#define FUTEX_OWNER_DIED 0x40000000 +#define FUTEX_TID_MASK 0x3fffffff + +#define FUTEX_ROBUST_LOCK_PI 1 +#define FUTEX_ROBUST_LIST_LIMIT 2048 + +extern long lx_futex(uintptr_t addr, int cmd, int val, uintptr_t lx_timeout, + uintptr_t addr2, int val2); +extern void lx_futex_init(void); +extern int lx_futex_fini(void); +extern long lx_set_robust_list(void *listp, size_t len); +extern long lx_get_robust_list(pid_t pid, void **listp, size_t *lenp); +extern void lx_futex_robust_exit(uintptr_t addr, uint32_t tid); + +#endif /* _KERNEL */ + +#ifdef __cplusplus +} +#endif + +#endif /* _SYS_LX_FUTEX_H */ |