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minix/servers/rs/main.c
Tomas Hruby 06b6e5624a SMP - Changed prototype of sys_schedule() 
- sys_schedule can change only selected values, -1 means that the
  current value should be kept unchanged. For instance we mostly want
  to change the scheduling quantum and priority but we want to keep
  the process at the current cpu

- RS can hand off its processes to scheduler

- service can read the destination cpu from system.conf

- RS can pass the information farther
2010-09-15 14:10:42 +00:00

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/* Reincarnation Server. This servers starts new system services and detects
* they are exiting. In case of errors, system services can be restarted.
* The RS server periodically checks the status of all registered services
* services to see whether they are still alive. The system services are
* expected to periodically send a heartbeat message.
*
* Changes:
* Nov 22, 2009: rewrite of boot process (Cristiano Giuffrida)
* Jul 22, 2005: Created (Jorrit N. Herder)
*/
#include "inc.h"
#include <fcntl.h>
#include <a.out.h>
#include <minix/crtso.h>
#include "kernel/const.h"
#include "kernel/type.h"
#include "kernel/proc.h"
/* Declare some local functions. */
FORWARD _PROTOTYPE(void boot_image_info_lookup, ( endpoint_t endpoint,
struct boot_image *image,
struct boot_image **ip, struct boot_image_priv **pp,
struct boot_image_sys **sp, struct boot_image_dev **dp) );
FORWARD _PROTOTYPE(void catch_boot_init_ready, (endpoint_t endpoint) );
FORWARD _PROTOTYPE(void get_work, (message *m_ptr, int *status_ptr) );
/* Flag set when memory unmapping can be done. */
EXTERN int unmap_ok;
/* SEF functions and variables. */
FORWARD _PROTOTYPE( void sef_local_startup, (void) );
FORWARD _PROTOTYPE( int sef_cb_init_fresh, (int type, sef_init_info_t *info) );
FORWARD _PROTOTYPE( void sef_cb_signal_handler, (int signo) );
FORWARD _PROTOTYPE( int sef_cb_signal_manager, (endpoint_t target, int signo) );
/*===========================================================================*
* main *
*===========================================================================*/
PUBLIC int main(void)
{
/* This is the main routine of this service. The main loop consists of
* three major activities: getting new work, processing the work, and
* sending the reply. The loop never terminates, unless a panic occurs.
*/
message m; /* request message */
int ipc_status; /* status code */
int call_nr, who_e,who_p; /* call number and caller */
int result; /* result to return */
int s;
/* SEF local startup. */
sef_local_startup();
if (OK != (s=sys_getmachine(&machine)))
panic("couldn't get machine info: %d", s);
/* Main loop - get work and do it, forever. */
while (TRUE) {
/* Wait for request message. */
get_work(&m, &ipc_status);
who_e = m.m_source;
if(rs_isokendpt(who_e, &who_p) != OK) {
panic("message from bogus source: %d", who_e);
}
call_nr = m.m_type;
/* Now determine what to do. Four types of requests are expected:
* - Heartbeat messages (notifications from registered system services)
* - System notifications (synchronous alarm)
* - User requests (control messages to manage system services)
* - Ready messages (reply messages from registered services)
*/
/* Notification messages are control messages and do not need a reply.
* These include heartbeat messages and system notifications.
*/
if (is_ipc_notify(ipc_status)) {
switch (who_p) {
case CLOCK:
do_period(&m); /* check services status */
continue;
default: /* heartbeat notification */
if (rproc_ptr[who_p] != NULL) { /* mark heartbeat time */
rproc_ptr[who_p]->r_alive_tm = m.NOTIFY_TIMESTAMP;
} else {
printf("RS: warning: got unexpected notify message from %d\n",
m.m_source);
}
}
}
/* If we get this far, this is a normal request.
* Handle the request and send a reply to the caller.
*/
else {
if (call_nr != COMMON_GETSYSINFO &&
(call_nr < RS_RQ_BASE || call_nr >= RS_RQ_BASE+0x100))
{
/* Ignore invalid requests. Do not try to reply. */
printf("RS: warning: got invalid request %d from endpoint %d\n",
call_nr, m.m_source);
continue;
}
/* Handler functions are responsible for permission checking. */
switch(call_nr) {
/* User requests. */
case RS_UP: result = do_up(&m); break;
case RS_DOWN: result = do_down(&m); break;
case RS_REFRESH: result = do_refresh(&m); break;
case RS_RESTART: result = do_restart(&m); break;
case RS_SHUTDOWN: result = do_shutdown(&m); break;
case RS_UPDATE: result = do_update(&m); break;
case RS_CLONE: result = do_clone(&m); break;
case RS_EDIT: result = do_edit(&m); break;
case COMMON_GETSYSINFO:
result = do_getsysinfo(&m); break;
case RS_LOOKUP: result = do_lookup(&m); break;
/* Ready messages. */
case RS_INIT: result = do_init_ready(&m); break;
case RS_LU_PREPARE: result = do_upd_ready(&m); break;
default:
printf("RS: warning: got unexpected request %d from %d\n",
m.m_type, m.m_source);
result = EINVAL;
}
/* Finally send reply message, unless disabled. */
if (result != EDONTREPLY) {
m.m_type = result;
reply(who_e, NULL, &m);
}
}
}
}
/*===========================================================================*
* sef_local_startup *
*===========================================================================*/
PRIVATE void sef_local_startup()
{
/* Register init callbacks. */
sef_setcb_init_response(do_init_ready);
sef_setcb_init_fresh(sef_cb_init_fresh);
sef_setcb_init_restart(sef_cb_init_fail);
/* Register live update callbacks. */
sef_setcb_lu_response(do_upd_ready);
/* Register signal callbacks. */
sef_setcb_signal_handler(sef_cb_signal_handler);
sef_setcb_signal_manager(sef_cb_signal_manager);
/* Let SEF perform startup. */
sef_startup();
}
/*===========================================================================*
* sef_cb_init_fresh *
*===========================================================================*/
PRIVATE int sef_cb_init_fresh(int type, sef_init_info_t *info)
{
/* Initialize the reincarnation server. */
struct boot_image *ip;
int s,i,j;
int nr_image_srvs, nr_image_priv_srvs, nr_uncaught_init_srvs;
struct rproc *rp;
struct rproc *replica_rp;
struct rprocpub *rpub;
struct boot_image image[NR_BOOT_PROCS];
struct boot_image_priv *boot_image_priv;
struct boot_image_sys *boot_image_sys;
struct boot_image_dev *boot_image_dev;
int pid, replica_pid;
endpoint_t replica_endpoint;
int ipc_to;
int *calls;
int all_c[] = { ALL_C, NULL_C };
int no_c[] = { NULL_C };
/* See if we run in verbose mode. */
env_parse("rs_verbose", "d", 0, &rs_verbose, 0, 1);
if ((s = sys_getinfo(GET_HZ, &system_hz, sizeof(system_hz), 0, 0)) != OK)
panic("Cannot get system timer frequency\n");
/* Initialize the global init descriptor. */
rinit.rproctab_gid = cpf_grant_direct(ANY, (vir_bytes) rprocpub,
sizeof(rprocpub), CPF_READ);
if(!GRANT_VALID(rinit.rproctab_gid)) {
panic("unable to create rprocpub table grant: %d", rinit.rproctab_gid);
}
/* Initialize some global variables. */
rupdate.flags = 0;
shutting_down = FALSE;
/* Get a copy of the boot image table. */
if ((s = sys_getimage(image)) != OK) {
panic("unable to get copy of boot image table: %d", s);
}
/* Determine the number of system services in the boot image table. */
nr_image_srvs = 0;
for(i=0;i<NR_BOOT_PROCS;i++) {
ip = &image[i];
/* System services only. */
if(iskerneln(_ENDPOINT_P(ip->endpoint))) {
continue;
}
nr_image_srvs++;
}
/* Determine the number of entries in the boot image priv table and make sure
* it matches the number of system services in the boot image table.
*/
nr_image_priv_srvs = 0;
for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
boot_image_priv = &boot_image_priv_table[i];
/* System services only. */
if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
continue;
}
nr_image_priv_srvs++;
}
if(nr_image_srvs != nr_image_priv_srvs) {
panic("boot image table and boot image priv table mismatch");
}
/* Reset the system process table. */
for (rp=BEG_RPROC_ADDR; rp<END_RPROC_ADDR; rp++) {
rp->r_flags = 0;
rp->r_pub = &rprocpub[rp - rproc];
rp->r_pub->in_use = FALSE;
}
/* Initialize the system process table in 4 steps, each of them following
* the appearance of system services in the boot image priv table.
* - Step 1: set priviliges, sys properties, and dev properties (if any)
* for every system service.
*/
for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
boot_image_priv = &boot_image_priv_table[i];
/* System services only. */
if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
continue;
}
/* Lookup the corresponding entries in other tables. */
boot_image_info_lookup(boot_image_priv->endpoint, image,
&ip, NULL, &boot_image_sys, &boot_image_dev);
rp = &rproc[boot_image_priv - boot_image_priv_table];
rpub = rp->r_pub;
/*
* Set privileges.
*/
/* Get label. */
strcpy(rpub->label, boot_image_priv->label);
/* Force a static priv id for system services in the boot image. */
rp->r_priv.s_id = static_priv_id(
_ENDPOINT_P(boot_image_priv->endpoint));
/* Initialize privilege bitmaps and signal manager. */
rp->r_priv.s_flags = boot_image_priv->flags; /* priv flags */
rp->r_priv.s_trap_mask= SRV_OR_USR(rp, SRV_T, USR_T); /* traps */
ipc_to = SRV_OR_USR(rp, SRV_M, USR_M); /* targets */
memcpy(&rp->r_priv.s_ipc_to, &ipc_to, sizeof(rp->r_priv.s_ipc_to));
rp->r_priv.s_sig_mgr= SRV_OR_USR(rp, SRV_SM, USR_SM); /* sig mgr */
rp->r_priv.s_bak_sig_mgr = NONE; /* backup sig mgr */
/* Initialize kernel call mask bitmap. */
calls = SRV_OR_USR(rp, SRV_KC, USR_KC) == ALL_C ? all_c : no_c;
fill_call_mask(calls, NR_SYS_CALLS,
rp->r_priv.s_k_call_mask, KERNEL_CALL, TRUE);
/* Set the privilege structure. */
if(boot_image_priv->endpoint != RS_PROC_NR) {
if ((s = sys_privctl(ip->endpoint, SYS_PRIV_SET_SYS, &(rp->r_priv)))
!= OK) {
panic("unable to set privilege structure: %d", s);
}
}
/* Synch the privilege structure with the kernel. */
if ((s = sys_getpriv(&(rp->r_priv), ip->endpoint)) != OK) {
panic("unable to synch privilege structure: %d", s);
}
/*
* Set sys properties.
*/
rpub->sys_flags = boot_image_sys->flags; /* sys flags */
/*
* Set dev properties.
*/
rpub->dev_flags = boot_image_dev->flags; /* device flags */
rpub->dev_nr = boot_image_dev->dev_nr; /* major device number */
rpub->dev_style = boot_image_dev->dev_style; /* device style */
rpub->dev_style2 = boot_image_dev->dev_style2; /* device style 2 */
/* Get process name. */
strcpy(rpub->proc_name, ip->proc_name);
/* Build command settings. */
rp->r_cmd[0]= '\0';
rp->r_script[0]= '\0';
build_cmd_dep(rp);
/* Initialize vm call mask bitmap. */
calls = SRV_OR_USR(rp, SRV_VC, USR_VC) == ALL_C ? all_c : no_c;
fill_call_mask(calls, NR_VM_CALLS, rpub->vm_call_mask, VM_RQ_BASE, TRUE);
/* Scheduling parameters. */
rp->r_scheduler = SRV_OR_USR(rp, SRV_SCH, USR_SCH);
rp->r_priority = SRV_OR_USR(rp, SRV_Q, USR_Q);
rp->r_quantum = SRV_OR_USR(rp, SRV_QT, USR_QT);
/* Get some settings from the boot image table. */
rpub->endpoint = ip->endpoint;
/* Set some defaults. */
rp->r_old_rp = NULL; /* no old version yet */
rp->r_new_rp = NULL; /* no new version yet */
rp->r_prev_rp = NULL; /* no prev replica yet */
rp->r_next_rp = NULL; /* no next replica yet */
rp->r_uid = 0; /* root */
rp->r_check_tm = 0; /* not checked yet */
getuptime(&rp->r_alive_tm); /* currently alive */
rp->r_stop_tm = 0; /* not exiting yet */
rp->r_restarts = 0; /* no restarts so far */
rp->r_period = 0; /* no period yet */
rp->r_exec = NULL; /* no in-memory copy yet */
rp->r_exec_len = 0;
/* Mark as in use and active. */
rp->r_flags = RS_IN_USE | RS_ACTIVE;
rproc_ptr[_ENDPOINT_P(rpub->endpoint)]= rp;
rpub->in_use = TRUE;
}
/* - Step 2: allow every system service in the boot image to run. */
nr_uncaught_init_srvs = 0;
for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
boot_image_priv = &boot_image_priv_table[i];
/* System services only. */
if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
continue;
}
/* Lookup the corresponding slot in the system process table. */
rp = &rproc[boot_image_priv - boot_image_priv_table];
rpub = rp->r_pub;
/* RS is already running as we speak. */
if(boot_image_priv->endpoint == RS_PROC_NR) {
if ((s = init_service(rp, SEF_INIT_FRESH)) != OK) {
panic("unable to initialize RS: %d", s);
}
continue;
}
/* Allow the service to run. */
if ((s = sched_init_proc(rp)) != OK) {
panic("unable to initialize scheduling: %d", s);
}
if ((s = sys_privctl(rpub->endpoint, SYS_PRIV_ALLOW, NULL)) != OK) {
panic("unable to initialize privileges: %d", s);
}
/* Initialize service. We assume every service will always get
* back to us here at boot time.
*/
if(boot_image_priv->flags & SYS_PROC) {
if ((s = init_service(rp, SEF_INIT_FRESH)) != OK) {
panic("unable to initialize service: %d", s);
}
if(rpub->sys_flags & SF_SYNCH_BOOT) {
/* Catch init ready message now to synchronize. */
catch_boot_init_ready(rpub->endpoint);
}
else {
/* Catch init ready message later. */
nr_uncaught_init_srvs++;
}
}
}
/* - Step 3: let every system service complete initialization by
* catching all the init ready messages left.
*/
while(nr_uncaught_init_srvs) {
catch_boot_init_ready(ANY);
nr_uncaught_init_srvs--;
}
/* - Step 4: all the system services in the boot image are now running.
* Complete the initialization of the system process table in collaboration
* with other system services.
*/
for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
boot_image_priv = &boot_image_priv_table[i];
/* System services only. */
if(iskerneln(_ENDPOINT_P(boot_image_priv->endpoint))) {
continue;
}
/* Lookup the corresponding slot in the system process table. */
rp = &rproc[boot_image_priv - boot_image_priv_table];
rpub = rp->r_pub;
/* Get pid from PM. */
rp->r_pid = getnpid(rpub->endpoint);
if(rp->r_pid == -1) {
panic("unable to get pid");
}
}
/* Set alarm to periodically check service status. */
if (OK != (s=sys_setalarm(RS_DELTA_T, 0)))
panic("couldn't set alarm: %d", s);
/* Now create a new RS instance with a private page table and let the current
* instance live update into the replica. Clone RS' own slot first.
*/
rp = rproc_ptr[_ENDPOINT_P(RS_PROC_NR)];
if((s = clone_slot(rp, &replica_rp)) != OK) {
panic("unable to clone current RS instance: %d", s);
}
/* Fork a new RS instance. */
pid = srv_fork();
if(pid == -1) {
panic("unable to fork a new RS instance");
}
replica_pid = pid ? pid : getpid();
replica_endpoint = getnprocnr(replica_pid);
replica_rp->r_pid = replica_pid;
replica_rp->r_pub->endpoint = replica_endpoint;
if(pid == 0) {
/* New RS instance running. */
/* Live update the old instance into the new one. */
s = update_service(&rp, &replica_rp, RS_SWAP);
if(s != OK) {
panic("unable to live update RS: %d", s);
}
cpf_reload();
/* Clean up the old RS instance, the new instance will take over. */
cleanup_service(rp);
/* Map out our own text and data. */
unmap_ok = 1;
_minix_unmapzero();
/* Ask VM to pin memory for the new RS instance. */
if((s = vm_memctl(RS_PROC_NR, VM_RS_MEM_PIN)) != OK) {
panic("unable to pin memory for the new RS instance: %d", s);
}
}
else {
/* Old RS instance running. */
/* Set up privileges for the new instance and let it run. */
s = sys_privctl(replica_endpoint, SYS_PRIV_SET_SYS, &(replica_rp->r_priv));
if(s != OK) {
panic("unable to set privileges for the new RS instance: %d", s);
}
if ((s = sched_init_proc(replica_rp)) != OK) {
panic("unable to initialize RS replica scheduling: %d", s);
}
s = sys_privctl(replica_endpoint, SYS_PRIV_YIELD, NULL);
if(s != OK) {
panic("unable to yield control to the new RS instance: %d", s);
}
NOT_REACHABLE;
}
return(OK);
}
/*===========================================================================*
* sef_cb_signal_handler *
*===========================================================================*/
PRIVATE void sef_cb_signal_handler(int signo)
{
/* Check for known signals, ignore anything else. */
switch(signo) {
case SIGCHLD:
do_sigchld();
break;
case SIGTERM:
do_shutdown(NULL);
break;
}
}
/*===========================================================================*
* sef_cb_signal_manager *
*===========================================================================*/
PRIVATE int sef_cb_signal_manager(endpoint_t target, int signo)
{
/* Process system signal on behalf of the kernel. */
int target_p;
struct rproc *rp;
struct rprocpub *rpub;
message m;
/* Lookup slot. */
if(rs_isokendpt(target, &target_p) != OK || rproc_ptr[target_p] == NULL) {
if(rs_verbose)
printf("RS: ignoring spurious signal %d for process %d\n",
signo, target);
return OK; /* clear the signal */
}
rp = rproc_ptr[target_p];
rpub = rp->r_pub;
/* Don't bother if a termination signal has already been processed. */
if((rp->r_flags & RS_TERMINATED) && !(rp->r_flags & RS_EXITING)) {
return EDEADEPT; /* process is gone */
}
/* Ignore external signals for inactive service instances. */
if( !(rp->r_flags & RS_ACTIVE) && !(rp->r_flags & RS_EXITING)) {
if(rs_verbose)
printf("RS: ignoring signal %d for inactive %s\n",
signo, srv_to_string(rp));
return OK; /* clear the signal */
}
if(rs_verbose)
printf("RS: %s got %s signal %d\n", srv_to_string(rp),
SIGS_IS_TERMINATION(signo) ? "termination" : "non-termination",signo);
/* Print stacktrace if necessary. */
if(SIGS_IS_STACKTRACE(signo)) {
sys_sysctl_stacktrace(target);
}
/* In case of termination signal handle the event. */
if(SIGS_IS_TERMINATION(signo)) {
rp->r_flags |= RS_TERMINATED;
terminate_service(rp);
return EDEADEPT; /* process is now gone */
}
/* Translate every non-termination signal into a message. */
m.m_type = SIGS_SIGNAL_RECEIVED;
m.SIGS_SIG_NUM = signo;
asynsend3(rpub->endpoint, &m, AMF_NOREPLY);
return OK; /* signal has been delivered */
}
/*===========================================================================*
* boot_image_info_lookup *
*===========================================================================*/
PRIVATE void boot_image_info_lookup(endpoint, image, ip, pp, sp, dp)
endpoint_t endpoint;
struct boot_image *image;
struct boot_image **ip;
struct boot_image_priv **pp;
struct boot_image_sys **sp;
struct boot_image_dev **dp;
{
/* Lookup entries in boot image tables. */
int i;
/* When requested, locate the corresponding entry in the boot image table
* or panic if not found.
*/
if(ip) {
for (i=0; i < NR_BOOT_PROCS; i++) {
if(image[i].endpoint == endpoint) {
*ip = &image[i];
break;
}
}
if(i == NR_BOOT_PROCS) {
panic("boot image table lookup failed");
}
}
/* When requested, locate the corresponding entry in the boot image priv table
* or panic if not found.
*/
if(pp) {
for (i=0; boot_image_priv_table[i].endpoint != NULL_BOOT_NR; i++) {
if(boot_image_priv_table[i].endpoint == endpoint) {
*pp = &boot_image_priv_table[i];
break;
}
}
if(i == NULL_BOOT_NR) {
panic("boot image priv table lookup failed");
}
}
/* When requested, locate the corresponding entry in the boot image sys table
* or resort to the default entry if not found.
*/
if(sp) {
for (i=0; boot_image_sys_table[i].endpoint != DEFAULT_BOOT_NR; i++) {
if(boot_image_sys_table[i].endpoint == endpoint) {
*sp = &boot_image_sys_table[i];
break;
}
}
if(boot_image_sys_table[i].endpoint == DEFAULT_BOOT_NR) {
*sp = &boot_image_sys_table[i]; /* accept the default entry */
}
}
/* When requested, locate the corresponding entry in the boot image dev table
* or resort to the default entry if not found.
*/
if(dp) {
for (i=0; boot_image_dev_table[i].endpoint != DEFAULT_BOOT_NR; i++) {
if(boot_image_dev_table[i].endpoint == endpoint) {
*dp = &boot_image_dev_table[i];
break;
}
}
if(boot_image_dev_table[i].endpoint == DEFAULT_BOOT_NR) {
*dp = &boot_image_dev_table[i]; /* accept the default entry */
}
}
}
/*===========================================================================*
* catch_boot_init_ready *
*===========================================================================*/
PRIVATE void catch_boot_init_ready(endpoint)
endpoint_t endpoint;
{
/* Block and catch an init ready message from the given source. */
int r;
int ipc_status;
message m;
struct rproc *rp;
int result;
/* Receive init ready message. */
if ((r = sef_receive_status(endpoint, &m, &ipc_status)) != OK) {
panic("unable to receive init reply: %d", r);
}
if(m.m_type != RS_INIT) {
panic("unexpected reply from service: %d", m.m_source);
}
result = m.RS_INIT_RESULT;
rp = rproc_ptr[_ENDPOINT_P(m.m_source)];
/* Check result. */
if(result != OK) {
panic("unable to complete init for service: %d", m.m_source);
}
/* Send a reply to unblock the service. */
m.m_type = OK;
reply(m.m_source, rp, &m);
/* Mark the slot as no longer initializing. */
rp->r_flags &= ~RS_INITIALIZING;
rp->r_check_tm = 0;
getuptime(&rp->r_alive_tm);
}
/*===========================================================================*
* get_work *
*===========================================================================*/
PRIVATE void get_work(m_ptr, status_ptr)
message *m_ptr; /* pointer to message */
int *status_ptr; /* pointer to status */
{
int r;
if (OK != (r=sef_receive_status(ANY, m_ptr, status_ptr)))
panic("sef_receive_status failed: %d", r);
}
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