minix/lib/syslib/sef.c
Cristiano Giuffrida d1fd04e72a Initialization protocol for system services.
SYSLIB CHANGES:
- SEF framework now supports a new SEF Init request type from RS. 3 different
callbacks are available (init_fresh, init_lu, init_restart) to specify
initialization code when a service starts fresh, starts after a live update,
or restarts.

SYSTEM SERVICE CHANGES:
- Initialization code for system services is now enclosed in a callback SEF will
automatically call at init time. The return code of the callback will
tell RS whether the initialization completed successfully.
- Each init callback can access information passed by RS to initialize. As of
now, each system service has access to the public entries of RS's system process
table to gather all the information required to initialize. This design
eliminates many existing or potential races at boot time and provides a uniform
initialization interface to system services. The same interface will be reused
for the upcoming publish/subscribe model to handle dynamic 
registration / deregistration of system services.

VM CHANGES:
- Uniform privilege management for all system services. Every service uses the
same call mask format. For boot services, VM copies the call mask from init
data. For dynamic services, VM still receives the call mask via rs_set_priv
call that will be soon replaced by the upcoming publish/subscribe model.

RS CHANGES:
- The system process table has been reorganized and split into private entries
and public entries. Only the latter ones are exposed to system services.
- VM call masks are now entirely configured in rs/table.c
- RS has now its own slot in the system process table. Only kernel tasks and
user processes not included in the boot image are now left out from the system
process table.
- RS implements the initialization protocol for system services.
- For services in the boot image, RS blocks till initialization is complete and
panics when failure is reported back. Services are initialized in their order of
appearance in the boot image priv table and RS blocks to implements synchronous
initialization for every system service having the flag SF_SYNCH_BOOT set.
- For services started dynamically, the initialization protocol is implemented
as though it were the first ping for the service. In this case, if the
system service fails to report back (or reports failure), RS brings the service
down rather than trying to restart it.
2010-01-08 01:20:42 +00:00

182 lines
5 KiB
C

#include "syslib.h"
#include <assert.h>
#include <minix/sysutil.h>
#include <stdio.h>
/* Self variables. */
#define SEF_SELF_NAME_MAXLEN 20
PRIVATE char sef_self_name[SEF_SELF_NAME_MAXLEN];
PRIVATE endpoint_t sef_self_endpoint;
/* Debug. */
#define SEF_DEBUG_HEADER_MAXLEN 32
PRIVATE time_t sef_debug_boottime = 0;
PRIVATE u32_t sef_debug_system_hz = 0;
PRIVATE time_t sef_debug_time_sec = 0;
PRIVATE time_t sef_debug_time_us = 0;
PRIVATE char sef_debug_header_buff[SEF_DEBUG_HEADER_MAXLEN];
FORWARD _PROTOTYPE( void sef_debug_refresh_params, (void) );
PUBLIC _PROTOTYPE( char* sef_debug_header, (void) );
/* SEF Init prototypes. */
EXTERN _PROTOTYPE( int do_sef_rs_init, (void) );
EXTERN _PROTOTYPE( int do_sef_init_request, (message *m_ptr) );
/* SEF Live update prototypes. */
EXTERN _PROTOTYPE( void do_sef_lu_before_receive, (void) );
EXTERN _PROTOTYPE( int do_sef_lu_request, (message *m_ptr) );
/* SEF Ping prototypes. */
EXTERN _PROTOTYPE( int do_sef_ping_request, (message *m_ptr) );
/*===========================================================================*
* sef_startup *
*===========================================================================*/
PUBLIC void sef_startup()
{
/* SEF startup interface for system processes. */
int r;
/* Get information about self. */
r = sys_whoami(&sef_self_endpoint, sef_self_name, SEF_SELF_NAME_MAXLEN);
if ( r != OK) {
sef_self_endpoint = SELF;
sprintf(sef_self_name, "%s", "Unknown");
}
#if INTERCEPT_SEF_INIT_REQUESTS
/* Intercept SEF Init requests. */
if(sef_self_endpoint == RS_PROC_NR) {
if((r = do_sef_rs_init()) != OK) {
panic("SEF", "unable to complete init", r);
}
}
else {
message m;
if((r = receive(RS_PROC_NR, &m)) != OK) {
panic("SEF", "unable to receive from RS", r);
}
if(IS_SEF_INIT_REQUEST(&m)) {
if((r = do_sef_init_request(&m)) != OK) {
panic("SEF", "unable to process init request", r);
}
}
else {
panic("SEF", "unable to receive init request", NO_NUM);
}
}
#endif
}
/*===========================================================================*
* sef_receive *
*===========================================================================*/
PUBLIC int sef_receive(endpoint_t src, message *m_ptr)
{
/* SEF receive() interface for system processes. */
int r;
while(TRUE) {
#if INTERCEPT_SEF_LU_REQUESTS
/* Handle SEF Live update before receive events. */
do_sef_lu_before_receive();
#endif
/* Receive and return in case of error. */
r = receive(src, m_ptr);
if(r != OK) {
return r;
}
#if INTERCEPT_SEF_PING_REQUESTS
/* Intercept SEF Ping requests. */
if(IS_SEF_PING_REQUEST(m_ptr)) {
if(do_sef_ping_request(m_ptr) == OK) {
continue;
}
}
#endif
#if INTERCEPT_SEF_LU_REQUESTS
/* Intercept SEF Live update requests. */
if(IS_SEF_LU_REQUEST(m_ptr)) {
if(do_sef_lu_request(m_ptr) == OK) {
continue;
}
}
#endif
/* If we get this far, this is not a valid SEF request, return and
* let the caller deal with that.
*/
break;
}
return r;
}
/*===========================================================================*
* sef_debug_refresh_params *
*===========================================================================*/
PRIVATE void sef_debug_refresh_params(void)
{
/* Refresh SEF debug params. */
clock_t uptime;
endpoint_t endpoint;
int r;
/* Get boottime the first time. */
if(!sef_debug_boottime) {
r = sys_times(NONE, NULL, NULL, NULL, &sef_debug_boottime);
if ( r != OK) {
sef_debug_boottime = -1;
}
}
/* Get system hz the first time. */
if(!sef_debug_system_hz) {
r = sys_getinfo(GET_HZ, &sef_debug_system_hz,
sizeof(sef_debug_system_hz), 0, 0);
if ( r != OK) {
sef_debug_system_hz = -1;
}
}
/* Get uptime. */
uptime = -1;
if(sef_debug_boottime!=-1 && sef_debug_system_hz!=-1) {
r = sys_times(NONE, NULL, NULL, &uptime, NULL);
if ( r != OK) {
uptime = -1;
}
}
/* Compute current time. */
if(sef_debug_boottime==-1 || sef_debug_system_hz==-1 || uptime==-1) {
sef_debug_time_sec = 0;
sef_debug_time_us = 0;
}
else {
sef_debug_time_sec = (time_t) (sef_debug_boottime
+ (uptime/sef_debug_system_hz));
sef_debug_time_us = (uptime%sef_debug_system_hz)
* 1000000/sef_debug_system_hz;
}
}
/*===========================================================================*
* sef_debug_header *
*===========================================================================*/
PUBLIC char* sef_debug_header(void)
{
/* Build and return a SEF debug header. */
sef_debug_refresh_params();
sprintf(sef_debug_header_buff, "%s: time = %ds %06dus",
sef_self_name, sef_debug_time_sec, sef_debug_time_us);
return sef_debug_header_buff;
}