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alert()-aware revive/select in log device

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This commit is contained in:
Ben Gras 2005-07-27 13:11:03 +00:00
parent e58db8b7f5
commit a1a7ccbd02
2 changed files with 98 additions and 16 deletions
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107
drivers/log/log.c
View file

@ -12,7 +12,7 @@
#include "../../kernel/const.h"
#include "../../kernel/type.h"
#define LOG_DEBUG 0 /* enable/ disable debugging */
#define LOG_DEBUG 1 /* enable/ disable debugging */
#define NR_DEVS 1 /* number of minor devices */
#define MINOR_KLOG 0 /* /dev/klog */
@ -65,9 +65,13 @@ PUBLIC void main(void)
log_geom[i].dv_size = cvul64(LOG_SIZE);
log_geom[i].dv_base = cvul64((long)logdevices[i].log_buffer);
logdevices[i].log_size = logdevices[i].log_read =
logdevices[i].log_write = logdevices[i].log_selected = 0;
logdevices[i].log_write =
logdevices[i].log_select_alerted =
logdevices[i].log_selected =
logdevices[i].log_select_ready_ops = 0;
#if SUSPENDABLE
logdevices[i].log_proc_nr = 0;
logdevices[i].log_revive_alerted = 0;
#endif
}
driver_task(&log_dtab);
@ -130,30 +134,38 @@ subwrite(struct logdevice *log, int count, int proc_nr, vir_bytes user_vir)
}
#if SUSPENDABLE
if(log->log_size > 0 && log->log_proc_nr) {
if(log->log_size > 0 && log->log_proc_nr && !log->log_revive_alerted) {
/* Someone who was suspended on read can now
* be revived.
*/
r = subread(log, log->log_iosize, log->log_proc_nr,
log->log_user_vir);
log_reply(REVIVE, log->log_source, log->log_proc_nr, r);
#if LOG_DEBUG
printf("revived to %d (%d) with %d bytes\n",
log->log_source, log->log_proc_nr, r);
#endif
log->log_proc_nr = 0;
}
log->log_status = subread(log, log->log_iosize,
log->log_proc_nr, log->log_user_vir);
printf("alert for revive %d..\n", log->log_source);
alert(log->log_source);
printf("alert for revive done..\n");
log->log_revive_alerted = 1;
/* log_reply(REVIVE, log->log_source, log->log_proc_nr, r); */
}
if(log->log_size > 0 && log->log_selected) {
if(log->log_size > 0)
log->log_select_ready_ops |= SEL_RD;
if(log->log_size > 0 && log->log_selected &&
!(log->log_select_alerted)) {
/* Someone(s) who was/were select()ing can now
* be awoken. If there was a blocking read (above),
* this can only happen if the blocking read didn't
* swallow all the data (log_size > 0).
*/
if(log->log_selected & SEL_RD) {
/*
log_notify(DEV_SELECTED,
log->log_select_proc, log_device, SEL_RD);
log->log_selected &= ~SEL_RD;
*/
printf("alert select\n");
alert(log->log_select_proc);
printf("alert select done\n");
log->log_select_alerted = 1;
#if LOG_DEBUG
printf("log notified %d\n", log->log_select_proc);
#endif
@ -257,6 +269,7 @@ unsigned nr_req; /* length of request vector */
log->log_proc_nr = proc_nr;
log->log_iosize = count;
log->log_user_vir = user_vir;
log->log_revive_alerted = 0;
/* Device_caller is a global in drivers library. */
log->log_source = device_caller;
@ -360,10 +373,70 @@ message *m_ptr;
if(d < 0 || d >= NR_DEVS)
return EINVAL;
logdevices[d].log_proc_nr = 0;
logdevices[d].log_revive_alerted = 0;
#endif
return(OK);
}
/*============================================================================*
* do_status *
*============================================================================*/
PRIVATE void do_status(message *m_ptr)
{
int d, nr = 0;
message m;
printf("do_status..\n");
/* Caller has requested pending status information, which currently
* can be pending available select()s, or REVIVE events. One message
* is returned for every event, or DEV_NO_STATUS if no (more) events
* are to be returned.
*/
for(d = 0; d < NR_DEVS; d++) {
/* Check for revive callback. */
if(logdevices[d].log_proc_nr && logdevices[d].log_revive_alerted
&& logdevices[d].log_source == m_ptr->m_source) {
m.m_type = DEV_REVIVE;
m.REP_PROC_NR = logdevices[d].log_proc_nr;
m.REP_STATUS = logdevices[d].log_status;
send(m_ptr->m_source, &m);
logdevices[d].log_proc_nr = 0;
logdevices[d].log_revive_alerted = 0;
#if LOG_DEBUG
printf("revived %d with %d bytes\n",
m.REP_PROC_NR, m.REP_STATUS);
#endif
return;
}
/* Check for select callback. */
if(logdevices[d].log_selected && logdevices[d].log_select_proc == m_ptr->m_source
&& logdevices[d].log_select_alerted) {
m.m_type = DEV_IO_READY;
m.DEV_SEL_OPS = logdevices[d].log_select_ready_ops;
m.DEV_MINOR = d;
#if LOG_DEBUG
printf("select sending sent\n");
#endif
send(m_ptr->m_source, &m);
logdevices[d].log_selected &= ~logdevices[d].log_select_ready_ops;
logdevices[d].log_select_alerted = 0;
#if LOG_DEBUG
printf("select send sent\n");
#endif
return;
}
}
/* No event found. */
m.m_type = DEV_NO_STATUS;
send(m_ptr->m_source, &m);
return;
}
/*============================================================================*
* log_other *
*============================================================================*/
@ -389,6 +462,12 @@ message *m_ptr;
r = EDONTREPLY;
break;
}
case DEV_STATUS: {
printf("status..\n");
do_status(m_ptr);
r = EDONTREPLY;
break;
}
default:
r = EINVAL;
break;

7
drivers/log/log.h
View file

@ -20,10 +20,13 @@ struct logdevice {
#if SUSPENDABLE
int log_proc_nr,
log_source,
log_iosize; /* proc that is blocking on read */
log_iosize,
log_revive_alerted,
log_status; /* proc that is blocking on read */
vir_bytes log_user_vir;
#endif
int log_selected, log_select_proc;
int log_selected, log_select_proc,
log_select_alerted, log_select_ready_ops;
};