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Fix and comment a race in SEF Init

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This commit is contained in:
Cristiano Giuffrida 2010-06-27 09:01:15 +00:00
parent f200f53a0b
commit 377f4e7e31
1 changed files with 16 additions and 10 deletions
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26
lib/libsys/sef.c
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@ -50,6 +50,7 @@ PUBLIC void sef_startup()
#if INTERCEPT_SEF_INIT_REQUESTS
/* Intercept SEF Init requests. */
if(sef_self_endpoint == RS_PROC_NR) {
/* RS initialization is special. */
if((r = do_sef_rs_init()) != OK) {
panic("unable to complete init: %d", r);
}
@ -57,17 +58,22 @@ PUBLIC void sef_startup()
else {
message m;
r = receive(RS_PROC_NR, &m, &status);
if(r != OK) {
panic("unable to receive from RS: %d", r);
}
if(IS_SEF_INIT_REQUEST(&m)) {
if((r = do_sef_init_request(&m)) != OK) {
panic("unable to process init request: %d", r);
/* Wait for an initialization message from RS. We need this to learn the
* initialization type and parameters. When restarting after a crash, we
* may get some spurious IPC messages from RS (e.g. update request) that
* were originally meant to be delivered to the old instance. We discard
* these messages and block till a proper initialization request arrives.
*/
do {
r = receive(RS_PROC_NR, &m, &status);
if(r != OK) {
panic("unable to receive from RS: %d", r);
}
}
else {
panic("got an unexpected message type %d", m.m_type);
} while(!IS_SEF_INIT_REQUEST(&m));
/* Process initialization request for this system service. */
if((r = do_sef_init_request(&m)) != OK) {
panic("unable to process init request: %d", r);
}
}
#endif