mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-21 20:40:05 +00:00
Update,
* nscd/connections.c: Rewrite handling of incoming connections. All are handled by one thread which then hands of the descriptors for the real work to the worker threads. * nscd/Makefile: Link nscd with librt. * nscd/selinux.c: Pretty printing. * nscd/dbg_log.c (dbg_log): Don't add unnecessary newline to output. Let syslog do the formatting if debug_level == 0.
This commit is contained in:
parent
1507c81f2a
commit
1945c96f2b
10
ChangeLog
10
ChangeLog
@ -1,5 +1,15 @@
|
||||
2004-10-02 Ulrich Drepper <drepper@redhat.com>
|
||||
|
||||
* nscd/connections.c: Rewrite handling of incoming connections. All
|
||||
are handled by one thread which then hands of the descriptors for the
|
||||
real work to the worker threads.
|
||||
* nscd/Makefile: Link nscd with librt.
|
||||
|
||||
* nscd/selinux.c: Pretty printing.
|
||||
|
||||
* nscd/dbg_log.c (dbg_log): Don't add unnecessary newline to
|
||||
output. Let syslog do the formatting if debug_level == 0.
|
||||
|
||||
* nscd/nscd_helper.c (get_mapping): No need to check timestamp if
|
||||
nscd_certainly_running is nonzero.
|
||||
|
||||
|
@ -112,9 +112,11 @@ $(objpfx)nscd: $(nscd-modules:%=$(objpfx)%.o)
|
||||
$(objpfx)nscd_nischeck: $(objpfx)nscd_nischeck.o
|
||||
|
||||
ifeq ($(build-shared),yes)
|
||||
$(objpfx)nscd: $(shared-thread-library) $(common-objpfx)nis/libnsl.so
|
||||
$(objpfx)nscd: $(common-objpfx)rt/librt.so $(shared-thread-library) \
|
||||
$(common-objpfx)nis/libnsl.so
|
||||
$(objpfx)nscd_nischeck: $(common-objpfx)nis/libnsl.so
|
||||
else
|
||||
$(objpfx)nscd: $(static-thread-library) $(common-objpfx)nis/libnsl.a
|
||||
$(objpfx)nscd: $(common-objpfx)rt/librt.a $(static-thread-library) \
|
||||
$(common-objpfx)nis/libnsl.a
|
||||
$(objpfx)nscd_nischeck: $(common-objpfx)nis/libnsl.a
|
||||
endif
|
||||
|
@ -785,91 +785,120 @@ cannot handle old request version %d; current version is %d"),
|
||||
}
|
||||
|
||||
|
||||
/* List of file descriptors. */
|
||||
struct fdlist
|
||||
{
|
||||
int fd;
|
||||
struct fdlist *next;
|
||||
};
|
||||
/* Memory allocated for the list. */
|
||||
static struct fdlist *fdlist;
|
||||
/* List of currently ready-to-read file descriptors. */
|
||||
static struct fdlist *readylist;
|
||||
|
||||
/* Conditional variable and mutex to signal availability of entries in
|
||||
READYLIST. The condvar is initialized dynamically since we might
|
||||
use a different clock depending on availability. */
|
||||
static pthread_cond_t readylist_cond;
|
||||
static pthread_mutex_t readylist_lock = PTHREAD_MUTEX_INITIALIZER;
|
||||
|
||||
/* The clock to use with the condvar. */
|
||||
static clockid_t timeout_clock = CLOCK_REALTIME;
|
||||
|
||||
/* Number of threads ready to handle the READYLIST. */
|
||||
static unsigned long int nready;
|
||||
|
||||
|
||||
/* This is the main loop. It is replicated in different threads but the
|
||||
`poll' call makes sure only one thread handles an incoming connection. */
|
||||
static void *
|
||||
__attribute__ ((__noreturn__))
|
||||
nscd_run (void *p)
|
||||
{
|
||||
long int my_number = (long int) p;
|
||||
struct pollfd conn;
|
||||
int run_prune = my_number < lastdb && dbs[my_number].enabled;
|
||||
time_t next_prune = run_prune ? time (NULL) + CACHE_PRUNE_INTERVAL : 0;
|
||||
static unsigned long int nready;
|
||||
const long int my_number = (long int) p;
|
||||
const int run_prune = my_number < lastdb && dbs[my_number].enabled;
|
||||
struct timespec prune_ts;
|
||||
int to = 0;
|
||||
char buf[256];
|
||||
|
||||
if (run_prune)
|
||||
setup_thread (&dbs[my_number]);
|
||||
{
|
||||
setup_thread (&dbs[my_number]);
|
||||
|
||||
conn.fd = sock;
|
||||
conn.events = POLLRDNORM;
|
||||
/* We are running. */
|
||||
dbs[my_number].head->timestamp = time (NULL);
|
||||
|
||||
if (clock_gettime (timeout_clock, &prune_ts) == -1)
|
||||
/* Should never happen. */
|
||||
abort ();
|
||||
|
||||
/* Compute timeout time. */
|
||||
prune_ts.tv_sec += CACHE_PRUNE_INTERVAL;
|
||||
}
|
||||
|
||||
/* Initial locking. */
|
||||
pthread_mutex_lock (&readylist_lock);
|
||||
|
||||
/* One more thread available. */
|
||||
++nready;
|
||||
|
||||
while (1)
|
||||
{
|
||||
int nr;
|
||||
time_t now = 0;
|
||||
|
||||
/* One more thread available. */
|
||||
atomic_increment (&nready);
|
||||
|
||||
no_conn:
|
||||
do
|
||||
while (readylist == NULL)
|
||||
{
|
||||
int timeout = -1;
|
||||
if (run_prune)
|
||||
{
|
||||
/* NB: we do not flush the timestamp update using msync since
|
||||
this value doesnot matter on disk. */
|
||||
dbs[my_number].head->timestamp = now = time (NULL);
|
||||
timeout = now < next_prune ? 1000 * (next_prune - now) : 0;
|
||||
/* Wait, but not forever. */
|
||||
to = pthread_cond_timedwait (&readylist_cond, &readylist_lock,
|
||||
&prune_ts);
|
||||
|
||||
/* If we were woken and there is no work to be done,
|
||||
just start pruning. */
|
||||
if (readylist == NULL && to == ETIMEDOUT)
|
||||
{
|
||||
pthread_mutex_unlock (&readylist_lock);
|
||||
goto only_prune;
|
||||
}
|
||||
}
|
||||
|
||||
nr = poll (&conn, 1, timeout);
|
||||
|
||||
if (nr == 0)
|
||||
{
|
||||
/* The `poll' call timed out. It's time to clean up the
|
||||
cache. */
|
||||
atomic_decrement (&nready);
|
||||
assert (my_number < lastdb);
|
||||
prune_cache (&dbs[my_number], time(NULL));
|
||||
now = time (NULL);
|
||||
next_prune = now + CACHE_PRUNE_INTERVAL;
|
||||
|
||||
goto try_get;
|
||||
}
|
||||
}
|
||||
while ((conn.revents & POLLRDNORM) == 0);
|
||||
|
||||
got_data:;
|
||||
/* We have a new incoming connection. Accept the connection. */
|
||||
int fd = TEMP_FAILURE_RETRY (accept (conn.fd, NULL, NULL));
|
||||
request_header req;
|
||||
char buf[256];
|
||||
uid_t uid = -1;
|
||||
#ifdef SO_PEERCRED
|
||||
pid_t pid = 0;
|
||||
#endif
|
||||
|
||||
if (__builtin_expect (fd, 0) < 0)
|
||||
{
|
||||
if (errno != EAGAIN && errno != EWOULDBLOCK)
|
||||
dbg_log (_("while accepting connection: %s"),
|
||||
strerror_r (errno, buf, sizeof (buf)));
|
||||
goto no_conn;
|
||||
else
|
||||
/* No need to timeout. */
|
||||
pthread_cond_wait (&readylist_cond, &readylist_lock);
|
||||
}
|
||||
|
||||
/* This thread is busy. */
|
||||
atomic_decrement (&nready);
|
||||
struct fdlist *it = readylist->next;
|
||||
if (readylist->next == readylist)
|
||||
/* Just one entry on the list. */
|
||||
readylist = NULL;
|
||||
else
|
||||
readylist->next = it->next;
|
||||
|
||||
/* Extract the information and mark the record ready to be used
|
||||
again. */
|
||||
int fd = it->fd;
|
||||
it->next = NULL;
|
||||
|
||||
/* One more thread available. */
|
||||
--nready;
|
||||
|
||||
/* We are done with the list. */
|
||||
pthread_mutex_unlock (&readylist_lock);
|
||||
|
||||
/* We do not want to block on a short read or so. */
|
||||
int fl = fcntl (fd, F_GETFL);
|
||||
if (fl == -1 || fcntl (fd, F_SETFL, fl | O_NONBLOCK) == -1)
|
||||
goto close_and_out;
|
||||
|
||||
/* Now read the request. */
|
||||
request_header req;
|
||||
if (__builtin_expect (TEMP_FAILURE_RETRY (read (fd, &req, sizeof (req)))
|
||||
!= sizeof (req), 0))
|
||||
{
|
||||
/* We failed to read data. Note that this also might mean we
|
||||
failed because we would have blocked. */
|
||||
if (debug_level > 0)
|
||||
dbg_log (_("short read while reading request: %s"),
|
||||
strerror_r (errno, buf, sizeof (buf)));
|
||||
close (fd);
|
||||
continue;
|
||||
goto close_and_out;
|
||||
}
|
||||
|
||||
/* Check whether this is a valid request type. */
|
||||
@ -878,7 +907,10 @@ nscd_run (void *p)
|
||||
|
||||
/* Some systems have no SO_PEERCRED implementation. They don't
|
||||
care about security so we don't as well. */
|
||||
uid_t uid = -1;
|
||||
#ifdef SO_PEERCRED
|
||||
pid_t pid = 0;
|
||||
|
||||
if (secure_in_use)
|
||||
{
|
||||
struct ucred caller;
|
||||
@ -909,8 +941,9 @@ nscd_run (void *p)
|
||||
|
||||
/* It should not be possible to crash the nscd with a silly
|
||||
request (i.e., a terribly large key). We limit the size to 1kb. */
|
||||
#define MAXKEYLEN 1024
|
||||
if (__builtin_expect (req.key_len, 1) < 0
|
||||
|| __builtin_expect (req.key_len, 1) > 1024)
|
||||
|| __builtin_expect (req.key_len, 1) > MAXKEYLEN)
|
||||
{
|
||||
if (debug_level > 0)
|
||||
dbg_log (_("key length in request too long: %d"), req.key_len);
|
||||
@ -918,17 +951,17 @@ nscd_run (void *p)
|
||||
else
|
||||
{
|
||||
/* Get the key. */
|
||||
char keybuf[req.key_len];
|
||||
char keybuf[MAXKEYLEN];
|
||||
|
||||
if (__builtin_expect (TEMP_FAILURE_RETRY (read (fd, keybuf,
|
||||
req.key_len))
|
||||
!= req.key_len, 0))
|
||||
{
|
||||
/* Again, this can also mean we would have blocked. */
|
||||
if (debug_level > 0)
|
||||
dbg_log (_("short read while reading request key: %s"),
|
||||
strerror_r (errno, buf, sizeof (buf)));
|
||||
close (fd);
|
||||
continue;
|
||||
goto close_and_out;
|
||||
}
|
||||
|
||||
if (__builtin_expect (debug_level, 0) > 0)
|
||||
@ -952,18 +985,193 @@ handle_request: request received (Version = %d)"), req.version);
|
||||
/* We are done. */
|
||||
close (fd);
|
||||
|
||||
/* Just determine whether any data is present. We do this to
|
||||
measure whether clients are queued up. */
|
||||
try_get:
|
||||
nr = poll (&conn, 1, 0);
|
||||
if (nr != 0)
|
||||
/* Check whether we should be pruning the cache. */
|
||||
assert (run_prune || to == 0);
|
||||
if (to == ETIMEDOUT)
|
||||
{
|
||||
if (nready == 0)
|
||||
++client_queued;
|
||||
only_prune:
|
||||
/* The pthread_cond_timedwait() call timed out. It is time
|
||||
to clean up the cache. */
|
||||
assert (my_number < lastdb);
|
||||
prune_cache (&dbs[my_number],
|
||||
prune_ts.tv_sec + (prune_ts.tv_nsec >= 500000000));
|
||||
|
||||
atomic_increment (&nready);
|
||||
if (clock_gettime (timeout_clock, &prune_ts) == -1)
|
||||
/* Should never happen. */
|
||||
abort ();
|
||||
|
||||
goto got_data;
|
||||
/* Compute next timeout time. */
|
||||
prune_ts.tv_sec += CACHE_PRUNE_INTERVAL;
|
||||
|
||||
/* In case the list is emtpy we do not want to run the prune
|
||||
code right away again. */
|
||||
to = 0;
|
||||
}
|
||||
|
||||
/* Re-locking. */
|
||||
pthread_mutex_lock (&readylist_lock);
|
||||
|
||||
/* One more thread available. */
|
||||
++nready;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
static void
|
||||
__attribute__ ((__noreturn__))
|
||||
main_loop (void)
|
||||
{
|
||||
/* Determine how much room for descriptors we should initially
|
||||
allocate. This might need to change later if we cap the number
|
||||
with MAXCONN. */
|
||||
const long int nfds = sysconf (_SC_OPEN_MAX);
|
||||
unsigned int nconns;
|
||||
#define MINCONN 32
|
||||
#define MAXCONN 16384
|
||||
if (nfds == -1 || nfds > MAXCONN)
|
||||
nconns = MAXCONN;
|
||||
else if (nfds < MINCONN)
|
||||
nconns = MINCONN;
|
||||
else
|
||||
nconns = nfds;
|
||||
|
||||
struct pollfd *conns = (struct pollfd *) xmalloc (nconns
|
||||
* sizeof (conns[0]));
|
||||
|
||||
/* We need two mirroring arrays filled with the times the connection
|
||||
was accepted and a place to pass descriptors on to the worker
|
||||
threads. We cannot put this in the same data structure as the
|
||||
CONNS data since CONNS is passed as an array to poll(). */
|
||||
time_t *starttime = (time_t *) xmalloc (nconns * sizeof (starttime[0]));
|
||||
fdlist = (struct fdlist *) xcalloc (nconns, sizeof (fdlist[0]));
|
||||
|
||||
conns[0].fd = sock;
|
||||
conns[0].events = POLLRDNORM;
|
||||
size_t nused = 1;
|
||||
size_t firstfree = 1;
|
||||
|
||||
while (1)
|
||||
{
|
||||
/* Wait for any event. We wait at most a couple of seconds so
|
||||
that we can check whether we should close any of the accepted
|
||||
connections since we have not received a request. */
|
||||
#define MAX_ACCEPT_TIMEOUT 30
|
||||
#define MIN_ACCEPT_TIMEOUT 5
|
||||
#define MAIN_THREAD_TIMEOUT \
|
||||
(MAX_ACCEPT_TIMEOUT * 1000 \
|
||||
- ((MAX_ACCEPT_TIMEOUT - MIN_ACCEPT_TIMEOUT) * 1000 * nused) / (2 * nconns))
|
||||
|
||||
int n = poll (conns, nused, MAIN_THREAD_TIMEOUT);
|
||||
|
||||
time_t now = time (NULL);
|
||||
|
||||
/* If there is a descriptor ready for reading or there is a new
|
||||
connection, process this now. */
|
||||
if (n > 0)
|
||||
{
|
||||
if (conns[0].revents != 0)
|
||||
{
|
||||
/* We have a new incoming connection. Accept the connection. */
|
||||
int fd = TEMP_FAILURE_RETRY (accept (sock, NULL, NULL));
|
||||
|
||||
if (fd >= 0)
|
||||
{
|
||||
/* We have a new file descriptor. Keep it around
|
||||
and wait until data becomes available. */
|
||||
if (firstfree == nconns)
|
||||
{
|
||||
// XXX Maybe extend array. For now, reject
|
||||
close (fd);
|
||||
goto reject_out;
|
||||
}
|
||||
|
||||
conns[firstfree].fd = fd;
|
||||
conns[firstfree].events = POLLRDNORM;
|
||||
starttime[firstfree] = now;
|
||||
if (firstfree >= nused)
|
||||
nused = firstfree + 1;
|
||||
|
||||
do
|
||||
++firstfree;
|
||||
while (firstfree < nused && conns[firstfree].fd != -1);
|
||||
}
|
||||
|
||||
reject_out:
|
||||
--n;
|
||||
}
|
||||
|
||||
for (size_t cnt = 1; cnt < nused && n > 0; ++cnt)
|
||||
if (conns[cnt].revents != 0)
|
||||
{
|
||||
pthread_mutex_lock (&readylist_lock);
|
||||
|
||||
/* Find an empty entry in FDLIST. */
|
||||
size_t inner;
|
||||
for (inner = 0; inner < nconns; ++inner)
|
||||
if (fdlist[inner].next == NULL)
|
||||
break;
|
||||
assert (inner < nconns);
|
||||
|
||||
fdlist[inner].fd = conns[cnt].fd;
|
||||
|
||||
if (readylist == NULL)
|
||||
readylist = fdlist[inner].next = &fdlist[inner];
|
||||
else
|
||||
{
|
||||
fdlist[inner].next = readylist->next;
|
||||
readylist = readylist->next = &fdlist[inner];
|
||||
}
|
||||
|
||||
bool do_signal = true;
|
||||
if (__builtin_expect (nready == 0, 0))
|
||||
{
|
||||
++client_queued;
|
||||
do_signal = false;
|
||||
}
|
||||
|
||||
pthread_mutex_unlock (&readylist_lock);
|
||||
|
||||
/* Tell one of the worker threads there is work to do. */
|
||||
if (do_signal)
|
||||
pthread_cond_signal (&readylist_cond);
|
||||
|
||||
/* Clean up the CONNS array. */
|
||||
conns[cnt].fd = -1;
|
||||
if (cnt < firstfree)
|
||||
firstfree = cnt;
|
||||
if (cnt == nused - 1)
|
||||
do
|
||||
--nused;
|
||||
while (conns[nused - 1].fd == -1);
|
||||
|
||||
--n;
|
||||
}
|
||||
}
|
||||
|
||||
/* Now find entries which have timed out. */
|
||||
assert (nused > 0);
|
||||
for (size_t cnt = nused - 1; cnt > 0; --cnt)
|
||||
{
|
||||
/* We make the timeout length depend on the number of file
|
||||
descriptors currently used. */
|
||||
#define ACCEPT_TIMEOUT \
|
||||
(MAX_ACCEPT_TIMEOUT \
|
||||
- ((MAX_ACCEPT_TIMEOUT - MIN_ACCEPT_TIMEOUT) * nused) / nconns)
|
||||
|
||||
time_t laststart = now - ACCEPT_TIMEOUT;
|
||||
if (conns[cnt].fd != -1 && starttime[cnt] < laststart)
|
||||
{
|
||||
/* Remove the entry, it timed out. */
|
||||
(void) close (conns[cnt].fd);
|
||||
conns[cnt].fd = -1;
|
||||
|
||||
if (cnt < firstfree)
|
||||
firstfree = cnt;
|
||||
if (cnt == nused - 1)
|
||||
do
|
||||
--nused;
|
||||
while (conns[nused - 1].fd == -1);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -973,10 +1181,26 @@ handle_request: request received (Version = %d)"), req.version);
|
||||
void
|
||||
start_threads (void)
|
||||
{
|
||||
long int i;
|
||||
pthread_attr_t attr;
|
||||
pthread_t th;
|
||||
/* Initialize the conditional variable we will use. The only
|
||||
non-standard attribute we might use is the clock selection. */
|
||||
pthread_condattr_t condattr;
|
||||
pthread_condattr_init (&condattr);
|
||||
|
||||
#if _POSIX_CLOCK_SELECTION >= 0 && _POSIX_MONOTONIC_CLOCK >= 0
|
||||
/* Determine whether the monotonous clock is available. */
|
||||
struct timespec dummy;
|
||||
if (clock_getres (CLOCK_MONOTONIC, &dummy) == 0
|
||||
&& pthread_condattr_setclock (&condattr, CLOCK_MONOTONIC) == 0)
|
||||
timeout_clock = CLOCK_MONOTONIC;
|
||||
#endif
|
||||
|
||||
pthread_cond_init (&readylist_cond, &condattr);
|
||||
pthread_condattr_destroy (&condattr);
|
||||
|
||||
|
||||
/* Create the attribute for the threads. They are all created
|
||||
detached. */
|
||||
pthread_attr_t attr;
|
||||
pthread_attr_init (&attr);
|
||||
pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
|
||||
|
||||
@ -984,12 +1208,17 @@ start_threads (void)
|
||||
if (debug_level == 0)
|
||||
nthreads = MAX (nthreads, lastdb);
|
||||
|
||||
for (i = 1; i < nthreads; ++i)
|
||||
pthread_create (&th, &attr, nscd_run, (void *) i);
|
||||
for (long int i = 0; i < nthreads; ++i)
|
||||
{
|
||||
pthread_t th;
|
||||
pthread_create (&th, &attr, nscd_run, (void *) i);
|
||||
}
|
||||
|
||||
pthread_attr_destroy (&attr);
|
||||
|
||||
nscd_run ((void *) 0);
|
||||
/* In the main thread we execute the loop which handles incoming
|
||||
connections. */
|
||||
main_loop ();
|
||||
}
|
||||
|
||||
|
||||
|
@ -61,7 +61,8 @@ dbg_log (const char *fmt,...)
|
||||
|
||||
if (debug_level > 0)
|
||||
{
|
||||
snprintf (msg, sizeof (msg), "%d: %s\n", getpid (), msg2);
|
||||
snprintf (msg, sizeof (msg), "%d: %s%s", getpid (), msg2,
|
||||
msg2[strlen (msg2) - 1] == '\n' ? "" : "\n");
|
||||
if (dbgout)
|
||||
{
|
||||
fputs (msg, dbgout);
|
||||
@ -71,9 +72,7 @@ dbg_log (const char *fmt,...)
|
||||
fputs (msg, stderr);
|
||||
}
|
||||
else
|
||||
{
|
||||
snprintf (msg, sizeof (msg), "%d: %s", getpid (), msg2);
|
||||
syslog (LOG_NOTICE, "%s", msg);
|
||||
}
|
||||
syslog (LOG_NOTICE, "%d %s", getpid (), msg2);
|
||||
|
||||
va_end (ap);
|
||||
}
|
||||
|
@ -207,8 +207,8 @@ nscd_request_avc_has_perm (int fd, request_type req)
|
||||
dbg_log (_("Error getting context of nscd"));
|
||||
goto out;
|
||||
}
|
||||
if (avc_context_to_sid (scon, &ssid) < 0 ||
|
||||
avc_context_to_sid (tcon, &tsid) < 0)
|
||||
if (avc_context_to_sid (scon, &ssid) < 0
|
||||
|| avc_context_to_sid (tcon, &tsid) < 0)
|
||||
{
|
||||
dbg_log (_("Error getting sid from context"));
|
||||
goto out;
|
||||
|
Loading…
Reference in New Issue
Block a user