diff options
Diffstat (limited to 'libvmon/vmon.h')
| -rw-r--r-- | libvmon/vmon.h | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/libvmon/vmon.h b/libvmon/vmon.h new file mode 100644 index 0000000..06a062b --- /dev/null +++ b/libvmon/vmon.h @@ -0,0 +1,308 @@ +#ifndef _VMON_H +#define _VMON_H + +#include <sys/types.h> +#include <dirent.h> +#include <stdint.h> +#include <string.h> /* I use strcmp() in the type comparator definitions */ + +#include "bitmap.h" +#include "list.h" + +#define VMON_HTAB_SIZE 128 /* number of buckets in the processes hash table */ +#define VMON_ARRAY_GROWBY 5 /* number of elements to grow the processes array */ + +typedef enum _vmon_flags_t { + VMON_FLAG_NONE = 0, + VMON_FLAG_PROC_ARRAY = 1L, /* maintain a process array (useful if you need to do things like implement top(1) */ + VMON_FLAG_PROC_ALL = 1L << 1, /* monitor all the processes in the system (XXX this has some follow_children implications...) */ + VMON_FLAG_2PASS = 1L << 2, /* perform all sampling/wants in a first pass, then invoke all callbacks in second in vmon_sample(), important if your callbacks are layout-sensitive (vwm) */ +} vmon_flags_t; + +/* store ids, used as indices into the stores array, and shift offsets for the wants mask */ +typedef enum _vmon_sys_store_t { +#define vmon_want(_sym, _name, _func) VMON_STORE_ ## _sym, +#include "defs/sys_wants.def" + VMON_STORE_SYS_NR +} vmon_sys_store_t; + +typedef enum _vmon_sys_wants_t { + VMON_WANT_SYS_NONE = 0, +#define vmon_want(_sym, _name, _func) VMON_WANT_ ## _sym = 1L << VMON_STORE_ ## _sym, +#include "defs/sys_wants.def" +} vmon_sys_wants_t; + +typedef enum _vmon_proc_store_t { +#define vmon_want(_sym, _name, _func) VMON_STORE_ ## _sym, +#include "defs/proc_wants.def" + VMON_STORE_PROC_NR +} vmon_proc_store_t; + +typedef enum _vmon_proc_wants_t { + VMON_WANT_PROC_INHERIT = 0, +#define vmon_want(_sym, _name, _func) VMON_WANT_ ## _sym = 1L << VMON_STORE_ ## _sym, +#include "defs/proc_wants.def" + /* XXX: note proc_wants is internally overloaded in libvmon to communicate when a process is a thread-child of a process, so not all bits are available. */ +} vmon_proc_wants_t; + + +/* we add some new complex types */ +typedef struct _vmon_char_array_t { + char *array; + int len; + int alloc_len; +} vmon_char_array_t; + +typedef struct _vmon_str_array_t { + char **array; + int len; + int alloc_len; +} vmon_str_array_t; + + +/* system stat stuff (/proc/stat...) */ +typedef enum _vmon_sys_stat_sym_t { +#define VMON_ENUM_SYMBOLS +#include "defs/sys_stat.def" + VMON_SYS_STAT_NR /* append this symbol to the end so we have a count */ +} vmon_sys_stat_sym_t; + +typedef struct _vmon_sys_stat_t { + int stat_fd; + + char changed[BITNSLOTS(VMON_SYS_STAT_NR)]; /* bitmap for indicating changed fields */ + +#define VMON_DECLARE_MEMBERS +#include "defs/sys_stat.def" +} vmon_sys_stat_t; + + +/* system vm/mem stuff (/proc/meminfo, /proc/vmstat...) */ +typedef enum _vmon_sys_vm_sym_t { +#define VMON_ENUM_SYMBOLS +#include "defs/sys_vm.def" + VMON_SYS_VM_NR /* append this symbol to the end so we have a count */ +} vmon_sys_vm_sym_t; + +typedef struct _vmon_sys_vm_t { + int meminfo_fd; + + char changed[BITNSLOTS(VMON_SYS_VM_NR)]; /* bitmap for indicating changed fields */ + +#define VMON_DECLARE_MEMBERS +#include "defs/sys_vm.def" +} vmon_sys_vm_t; + + +/* stat things we always monitor for a process, regardless of the caller's wants */ +typedef enum _vmon_proc_stat_sym_t { +#define VMON_ENUM_SYMBOLS +#include "defs/proc_stat.def" + VMON_PROC_STAT_NR /* append this symbol to the end so we have a count */ +} vmon_proc_stat_sym_t; + +typedef struct _vmon_proc_stat_t { + int cmdline_fd, comm_fd, wchan_fd, stat_fd; /* per-process stat monitoring /proc/$pid/{wchan,stat} file handles */ + + char changed[BITNSLOTS(VMON_PROC_STAT_NR)]; /* bitmap for indicating changed fields */ + +#define VMON_DECLARE_MEMBERS +#include "defs/proc_stat.def" +} vmon_proc_stat_t; + + +/* vm-related per-process things we can monitor */ +typedef enum _vmon_proc_vm_sym_t { +#define VMON_ENUM_SYMBOLS +#include "defs/proc_vm.def" + VMON_PROC_VM_NR /* append this symbol to the end so we have a count */ +} vmon_proc_vm_sym_t; + +typedef struct _vmon_proc_vm_t { + int statm_fd; /* per-process vm monitoring /proc/$pid/statm file handle */ + + char changed[BITNSLOTS(VMON_PROC_VM_NR)]; /* bitmap for indicating changed fields */ + +#define VMON_DECLARE_MEMBERS +#include "defs/proc_vm.def" +} vmon_proc_vm_t; + + +/* io-related per-process things we can monitor */ +typedef enum _vmon_proc_io_sym_t { +#define VMON_ENUM_SYMBOLS +#include "defs/proc_io.def" + VMON_PROC_IO_NR /* append this symbol to the end so we have a count */ +} vmon_proc_io_sym_t; + +typedef struct _vmon_proc_io_t { + int io_fd; /* per-process io monitoring /proc/$pid/io file handle */ + + char changed[BITNSLOTS(VMON_PROC_IO_NR)]; /* bitmap for indicating changed fields */ + +#define VMON_DECLARE_MEMBERS +#include "defs/proc_io.def" +} vmon_proc_io_t; + + +/* follow children want context */ +typedef struct _vmon_proc_follow_children_t { + int children_fd; /* per-process children following /proc/$pid/task/$pid/children file handle */ +} vmon_proc_follow_children_t; + + +/* follow threads want context */ +typedef struct _vmon_proc_follow_threads_t { + DIR *task_dir; /* per-process threads monitoring /proc/$pid/task handle */ +} vmon_proc_follow_threads_t; + + +/* open files monitoring */ +typedef enum _vmon_proc_files_sym_t { +#define VMON_ENUM_SYMBOLS +#include "defs/proc_files.def" +} vmon_proc_files_sym_t; + +typedef enum _vmon_fobject_type_t { + VMON_FOBJECT_TYPE_UNRECOGNIZED = 0, + /* TODO, enumerate the possible opened fobject types, this should come out of a .def */ + VMON_FOBJECT_TYPE_PIPE, + VMON_FOBJECT_TYPE_SOCKET, + VMON_FOBJECT_TYPE_ANON, + VMON_FOBJECT_TYPE_NR +} vmon_fobject_type_t; + +typedef struct _vmon_fobject_t { + list_head_t bucket; /* fobjects hash table bucket this fobject belongs to */ + uint64_t inum; /* inode number */ + list_head_t ref_fds; /* referring fds list, this is a list of proc_fd_t's which appear to have this object open */ + int refcnt; /* reference count, this may be greater than the # of nodes in ref_fds, for instance the + monitoring of /proc/net/unix will maintain references to fobjects for every row, without + maintaing nodes on ref_fds. But there are certain fobjects which simply emerge due to + processes having them open (pipes) which are not explicitly monitored elsewhere, in those + cases the refcnt and number of nodes in ref_fds shall match. */ + vmon_fobject_type_t type; /* type for this fobject */ + + + /* TODO: possibly hook into the object-type-specific information here, if so, it should come out of .defs */ + /* XXX the question is do I want to introduce that resource allocation here as part of the fobject, or do I want + * it elsewhere and potentially optional? I think it makes sense to make it optional and triggered by asking for + * fobject detail monitoring, so instead of a union here we should have a pointer, and that pointer becomes useful + * when fobject-type monitors become active */ + void *foo; /* hook for caller's data, if needed (expected to be used together with fobject_[cd]tor_cb) */ +} vmon_fobject_t; + +typedef struct _vmon_proc_fd_t { + list_head_t fds; /* per-process files list node */ + int generation; /* generation number, for convenient detection of closed files */ + struct _vmon_proc_t *process; /* process this fd belongs to (annoying, but enables linking processes with fobject refs) */ + list_head_t ref_fds; /* ref_fds list node */ + vmon_fobject_t *object; /* the object instance this fd refers to (this object also contains the head for the refs list) */ + +#define VMON_DECLARE_MEMBERS +#include "defs/proc_files.def" +} vmon_proc_fd_t; + +typedef struct _vmon_proc_files_t { + int refcnt; /* reference count for dealing with sharing of open files (like threads...) */ + DIR *fd_dir; /* per-process files /proc/$pid/fd handle */ + list_head_t fds; /* per-process files linked list head */ +} vmon_proc_files_t; + + +/* TODO per-process VM stats monitoring */ + +struct _vmon_t; + + +/* list of callbacks is maintained for the per-process callbacks, it's convenient to do things like update multiple dynamic contexts associated with a given process monitor (think multiple windows) */ +typedef struct _vmon_proc_callback_t { + void (*func)(struct _vmon_t *, struct _vmon_proc_t *, void *); + void *arg; + list_head_t callbacks; +} vmon_proc_callback_t; + +typedef struct _vmon_proc_t { + list_head_t bucket; /* processes hash table bucket this process belongs to */ + + list_head_t children; /* head of the children of this process, empty when no children */ + list_head_t siblings; /* node in siblings list */ + list_head_t threads; /* head or node for the threads list, empty when process has no threads */ + + struct _vmon_proc_t *parent; /* reference to the parent */ + + int array_hint_pos; /* hint for the process's position in the array (when array maintenance has been requested) */ + + int pid; /* the PID of the process being monitored */ + + int generation; /* generation number, for convenient detection of exited processes */ + int refcnt; /* reference count on this node */ + vmon_proc_wants_t wants; /* wants @ this node */ + + vmon_proc_wants_t activity; /* bits updated when there's activity on the respective wants (stores have changes) */ + void *stores[VMON_STORE_PROC_NR]; /* pointers to the per-want per-monitored-process storage space */ + + /* callbacks invoked after sampling wants at and below this node */ + list_head_t sample_callbacks; /* list of callbacks to invoke sample_cb on behalf of (and supply as parameteres to) */ + void *foo; /* another per-process hook for whatever per-process uses the caller may have, but not managed by the api */ + + int children_changed:1; /* gets set when any of my immediate children have had is_new or is_stale set in the last sample */ + int threads_changed:1; /* gets set when any of my threads have had is_new or is_stale set in the last sample */ + int is_new:1; /* process is new in the most recent sample, automatically cleared on subsequent sample */ + int is_stale:1; /* process became stale in the most recent sample, automatically cleared on subsequent sample (process will be discarded) */ + int is_thread:1; /* process is a thread belonging to parent */ +} vmon_proc_t; + + +typedef struct _vmon_t { + DIR *proc_dir; /* /proc is opened @ vmon_init() */ + + /* TODO: rename this to something more contextually processes-specific */ + /* these array members are only relevant when array maintenance has been requested via VMON_FLAG_PROC_ARRAY @ vmon_init() */ + vmon_proc_t **array; /* array of processes being monitored (flat) */ + int array_allocated_nr; /* number of entries in the table */ + int array_active_nr; /* number of processes present in the table (including stale) */ + int array_hint_free; /* hint for a free element in the list */ + + list_head_t htab[VMON_HTAB_SIZE]; /* hash table for quickly finding processes being monitored */ + list_head_t processes; /* top of the processes heirarchy */ + list_head_t orphans; /* ephemeral list of processes orphaned this sample, orphans wind up becoming top-level processes */ + int processes_changed:1; /* flag set when the toplevel processes list changes */ + + list_head_t fobjects; /* XXX TODO: temporary single fobjects table, in the future this will be an array of type-indexed + * fobject hash tables */ + int fobjects_nr; /* XXX TODO: temporary simple counter of number of fobjects, this will change into something + * more like we have for the proceses array */ + vmon_flags_t flags; /* instance flags */ + vmon_sys_wants_t sys_wants; /* system-wide wants mask */ + vmon_proc_wants_t proc_wants; /* inherited per-process wants mask */ + + /* function tables for mapping of wants bits to functions (sys-wide and per-process) */ + int (*sys_funcs[VMON_STORE_SYS_NR])(struct _vmon_t *, void **); + int (*proc_funcs[VMON_STORE_PROC_NR])(struct _vmon_t *, vmon_proc_t *, void **); + + vmon_sys_wants_t activity; /* bits updated when there's activity on the respective wants (stores have changes) */ + void *stores[VMON_STORE_SYS_NR]; /* stores for the sys-wide wants */ + void (*sample_cb)(struct _vmon_t *); /* callback invoked after executing the selected sys wants (once per vmon_sample() call)) */ + + char buf[8192]; /* scratch buffer for private use XXX: it may make sense to dynamically size these... */ + char buf_bis[8192]; /* secondary scratch buffer for private use */ + int generation; /* generation counter for whatever might need it, increments with vmon_sample() calls */ + + /* callbacks we'll invoke in response to processes becoming instantiated and destroyed, when set */ + void (*proc_ctor_cb)(struct _vmon_t *, vmon_proc_t *); + void (*proc_dtor_cb)(struct _vmon_t *, vmon_proc_t *); + + /* callbacks we'll invoke in response to fobjects becoming instantiated and destroyed, when set */ + void (*fobject_ctor_cb)(struct _vmon_t *, vmon_fobject_t *); + void (*fobject_dtor_cb)(struct _vmon_t *, vmon_fobject_t *); +} vmon_t; + + +int vmon_init(vmon_t *, vmon_flags_t, vmon_sys_wants_t, vmon_proc_wants_t); +void vmon_destroy(vmon_t *); +vmon_proc_t * vmon_proc_monitor(vmon_t *, vmon_proc_t *, int, vmon_proc_wants_t, void (*)(vmon_t *, vmon_proc_t *, void *), void *); +void vmon_proc_unmonitor(vmon_t *, vmon_proc_t *, void (*)(vmon_t *, vmon_proc_t *, void *), void *); +int vmon_sample(vmon_t *); + +#endif |