plan9fox/sys/include/ape/qlock.h
cinap_lenrek 3794b1c14f libc: improve alignment of QLp structure on amd64, cosmetics
the QLp structure used to occupy 24 bytes on amd64.
with some rearranging the fields we can get it to 16 bytes,
saving 8K in the data section for the 1024 preallocated
structs in the ql arena.

the rest of the changes are of cosmetic nature:

- getqlp() zeros the next pointer, so there is no need to set
  it when queueing the entry.

- always explicitely compare pointers to nil.

- delete unused code from ape's qlock.c
2017-10-28 18:53:27 +02:00

41 lines
507 B
C

#ifndef _PLAN9_SOURCE
This header file is an extension to ANSI/POSIX
#endif
#ifndef __QLOCK_H_
#define __QLOCK_H_
#pragma lib "/$M/lib/ape/lib9.a"
#include <u.h>
#include <lock.h>
typedef struct QLp QLp;
struct QLp
{
int inuse;
int state;
QLp *next;
};
typedef
struct QLock
{
Lock lock;
int locked;
QLp *head;
QLp *tail;
} QLock;
#ifdef __cplusplus
extern "C" {
#endif
extern void qlock(QLock*);
extern void qunlock(QLock*);
extern int canqlock(QLock*);
#ifdef __cplusplus
}
#endif
#endif