cvs commit: apache-apr/pthreads/src/main http_accept.c http_main.c
manoj 99/05/23 19:10:28
Modified:pthreads/src/include http_main.h
pthreads/src/main http_accept.c http_main.c
Log:
Switch to using a pipe to notify children of graceful shutodwn instead
of a signal. This also naturally solves a problem with graceful shutdown
of children blocked on the accept mutex.
Revision ChangesPath
1.6 +3 -0 apache-apr/pthreads/src/include/http_main.h
Index: http_main.h
===
RCS file: /home/cvs/apache-apr/pthreads/src/include/http_main.h,v
retrieving revision 1.5
retrieving revision 1.6
diff -u -u -r1.5 -r1.6
--- http_main.h 1999/04/09 04:10:35 1.5
+++ http_main.h 1999/05/24 02:10:25 1.6
@@ -58,6 +58,9 @@
#ifndef APACHE_HTTP_MAIN_H
#define APACHE_HTTP_MAIN_H
+/* Pipe used to signal a graceful child shutdown */
+extern int ap_pipe_of_death[2];
+
#ifdef __cplusplus
extern "C" {
#endif
1.15 +19 -15apache-apr/pthreads/src/main/http_accept.c
Index: http_accept.c
===
RCS file: /home/cvs/apache-apr/pthreads/src/main/http_accept.c,v
retrieving revision 1.14
retrieving revision 1.15
diff -u -u -r1.14 -r1.15
--- http_accept.c 1999/05/20 05:00:41 1.14
+++ http_accept.c 1999/05/24 02:10:26 1.15
@@ -331,7 +331,6 @@
*/
static listen_rec *head_listener;
static struct pollfd *listenfds;
-static int pipe_of_death;
void accept_parent_init(pool *pconf, int listener_count)
{
@@ -344,7 +343,6 @@
int worker_threads_per_child)
{
int i;
-int pipe_pair_of_death[2];
listen_rec *lr;
SAFE_ACCEPT(intra_mutex_init(pchild, 1));
@@ -353,15 +351,7 @@
head_listener = ap_listeners;
listenfds = ap_palloc(pchild, sizeof(struct pollfd) * (num_listenfds +
1));
-
-if (pipe(pipe_pair_of_death) == -1) {
-ap_log_error(APLOG_MARK, APLOG_ERR,
- (const server_rec*) ap_get_server_conf(),
- "pipe: (pipe_of_death)");
- clean_child_exit(1);
-}
-pipe_of_death = pipe_pair_of_death[1];
-listenfds[0].fd = pipe_pair_of_death[0];
+listenfds[0].fd = ap_pipe_of_death[0];
listenfds[0].events = POLLIN;
listenfds[0].revents = 0;
for (lr = ap_listeners, i = 1; i <= num_listenfds; lr = lr->next, ++i) {
@@ -380,7 +370,9 @@
int csd = -1;
int sd;
int srv;
+int ret;
listen_rec *lr;
+char pipe_read_char;
size_t len = sizeof(struct sockaddr);
@@ -400,6 +392,21 @@
break;
srv = poll(listenfds, num_listenfds + 1, -1);
+if (listenfds[0].revents & POLLIN) {
+/* A process has gotten a signal on the shutdown pipe.
+ * Check if we're the lucky process to die. */
+ret = read(listenfds[0].fd, &pipe_read_char, 1);
+if (ret == -1 && errno == EAGAIN) {
+/* It lost the lottery. It must continue to suffer
through
+ * a life of servitude */
+continue;
+}
+else {
+/* It won the lottery (or something else is very wrong).
+ * Embrace death with open arms. */
+break;
+}
+}
if (workers_may_exit)
break;
if (srv < 0) {
@@ -472,6 +479,7 @@
break;
}
}
+workers_may_exit = 1;
return -1;
}
@@ -479,15 +487,11 @@
{
int i;
int index = find_child_by_pid(getpid());
-char char_of_death = '!';
parent_score *ss = &ap_scoreboard_image->parent[index];
requests_this_child = 0;
workers_may_exit = 1;
-
-/* Kick threads out of poll */
-(void) write(pipe_of_death, &char_of_death, 1);
for (i = 0; i < ss->worker_threads; i++) {
pthread_join(ap_scoreboard_image->servers[index][i].tid, NULL);
1.81 +26 -9 apache-apr/pthreads/src/main/http_main.c
Index: http_main.c
===
RCS file: /home/cvs/apache-apr/pthreads/src/main/http_main.c,v
retrieving revision 1.80
retrieving revision 1.81
diff -u -u -r1.80 -r1.81
--- http_main.c 1999/05/20 04:33:32 1.80
+++ http_main.c 1999/05/24 02:10:27 1.81
@@ -216,6 +216,7 @@
array_header *ap_server_config_defines;
pool *pchild;/* Pool for httpd child stuff */
+int ap_pipe_of_death[2];
/* thread local storage code that isn't used right now */
@@ -1963,7 +1964,6 @@
/* XXX - Do the appropriate thing for each signal */
switch
cvs commit: apache-apr/pthreads/src/main http_accept.c http_main.c
manoj 99/04/29 12:34:23
Modified:.STATUS
pthreads/src/main http_accept.c http_main.c
Log:
Get rid of thread_starter_thread, and just start all of our worker
threads from child_main. This makes the code simpler, and eliminates
any race conditions involving trying to shutdown a child process while
still starting threads.
Revision ChangesPath
1.23 +1 -9 apache-apr/STATUS
Index: STATUS
===
RCS file: /home/cvs/apache-apr/STATUS,v
retrieving revision 1.22
retrieving revision 1.23
diff -u -u -r1.22 -r1.23
--- STATUS1999/04/27 06:23:04 1.22
+++ STATUS1999/04/29 19:34:19 1.23
@@ -1,5 +1,5 @@
Apache Portable Runtime STATUS:
-Last modified at [$Date: 1999/04/27 06:23:04 $]
+Last modified at [$Date: 1999/04/29 19:34:19 $]
Release:
@@ -42,14 +42,6 @@
Everything
Needs patch:
-
-On Red Hat 5.2, with a very low MaxRequestsPerChild (e.g. 10), when the
-server is banged on with ApacheBench, occasionally, the main thread of a
-process hangs around in pthread_exit_process. The size of that process is
-always around 11M. This bug is also exhibited by sending lots of SIGHUPs
-to the parent process rapidly (but not SIGWINCHes). The suspicion is that
-this is either an error in how pthread calls are used in the server, or a
-libc bug (the last refuge of a desperate programer).
When the server runs at a high load, and the load later drops off,
the server tries to kill off some children. The problem is that the
1.11 +1 -12 apache-apr/pthreads/src/main/http_accept.c
Index: http_accept.c
===
RCS file: /home/cvs/apache-apr/pthreads/src/main/http_accept.c,v
retrieving revision 1.10
retrieving revision 1.11
diff -u -u -r1.10 -r1.11
--- http_accept.c 1999/04/22 05:46:53 1.10
+++ http_accept.c 1999/04/29 19:34:20 1.11
@@ -245,7 +245,7 @@
*/
int i = ap_threads_per_child;
if (lr) {
-while (lr->next != NULL) {
+while (lr != NULL) {
(void) ap_update_child_status(my_child_num, i, SERVER_STARTING,
(request_rec *) NULL);
@@ -277,17 +277,6 @@
/* no listening sockets Kill the server please. */
exit(0);
}
-(void) ap_update_child_status(my_child_num, i, SERVER_STARTING,
- (request_rec *) NULL);
-
-my_info = NULL;
-
-my_info = (proc_info *) malloc(sizeof(proc_info));
-my_info->pid = my_child_num;
-my_info->tid = i;
-my_info->sd = lr->fd;
-
-accept_thread(my_info);
}
int get_connection(struct sockaddr *sa_client)
1.78 +31 -52apache-apr/pthreads/src/main/http_main.c
Index: http_main.c
===
RCS file: /home/cvs/apache-apr/pthreads/src/main/http_main.c,v
retrieving revision 1.77
retrieving revision 1.78
diff -u -u -r1.77 -r1.78
--- http_main.c 1999/04/22 04:14:40 1.77
+++ http_main.c 1999/04/29 19:34:21 1.78
@@ -1884,61 +1884,16 @@
#endif /* ndef WIN32 */
}
-static void *thread_starter_thread(void *thread_arg) {
-int i;
-pthread_t thread;
-int my_child_num = *((int *) thread_arg);
-proc_info *my_info = NULL;
-
-/* Setup worker threads */
-for (i=0; i < ap_threads_per_child; i++) {
-
-my_info = NULL;
-
- my_info = (proc_info *)malloc(sizeof(proc_info));
- my_info->pid = my_child_num;
-my_info->tid = i;
- my_info->sd = 0;
-
- /* We are creating threads right now */
- (void) ap_update_child_status(my_child_num, i, SERVER_STARTING,
- (request_rec *) NULL);
- if (pthread_create(&thread, NULL, worker_thread, my_info)) {
- ap_log_error(APLOG_MARK, APLOG_ALERT, server_conf,
- "pthread_create: unable to create worker thread");
- /*
- * We failed to create a thread. Update the scoreboard,
- * or it will say SERVER_STARTING forever.
- */
- (void) ap_update_child_status(my_child_num, i, SERVER_DEAD,
- (request_rec *) NULL);
- exit(1); /* We won't always exit here, but for no this is okay */
- }
-
- /* We let each thread update it's own scoreboard entry. This is done
- * because it let's us deal with tid better.
- */
-}
-
-
-/* Begin accepting requests
- * Design:
- *
- */
-start_accepting_connections(my_child_num);
-return NULL;
-}
-
static void child_main(int c
cvs commit: apache-apr/pthreads/src/main http_accept.c http_main.c
manoj 99/04/16 21:25:57
Modified:pthreads/src/include http_accept.h
pthreads/src/main http_accept.c http_main.c
Log:
An attempt to put SINGLE_LISTEN_UNSERIALIZED_ACCEPT support back in.
This also moves the SAFE_ACCEPT definition from http_accept.h to
http_accept.c since it isn't (and shouldn't be) used in other files
anymore.
Revision ChangesPath
1.6 +0 -2 apache-apr/pthreads/src/include/http_accept.h
Index: http_accept.h
===
RCS file: /home/cvs/apache-apr/pthreads/src/include/http_accept.h,v
retrieving revision 1.5
retrieving revision 1.6
diff -u -u -r1.5 -r1.6
--- http_accept.h 1999/04/17 03:35:53 1.5
+++ http_accept.h 1999/04/17 04:25:55 1.6
@@ -65,8 +65,6 @@
#include "httpd.h"
#include "ap_config.h"
-#define SAFE_ACCEPT(stmt) do {stmt;} while(0)
-
/* The info each server thread needs to start correctly.
*/
typedef struct {
1.9 +16 -0 apache-apr/pthreads/src/main/http_accept.c
Index: http_accept.c
===
RCS file: /home/cvs/apache-apr/pthreads/src/main/http_accept.c,v
retrieving revision 1.8
retrieving revision 1.9
diff -u -u -r1.8 -r1.9
--- http_accept.c 1999/04/17 01:58:58 1.8
+++ http_accept.c 1999/04/17 04:25:56 1.9
@@ -72,6 +72,15 @@
static int num_listenfds;
#if defined (USE_ACCEPT_QUEUE)
+
+#ifdef SINGLE_LISTEN_UNSERIALIZED_ACCEPT
+/* Each thread only listens to one socket in this model, so the starvation
+ * problem described in manual/misc/perf-tuning.html can't occur here */
+#define SAFE_ACCEPT(stmt)
+#else
+#define SAFE_ACCEPT(stmt) do {stmt;} while(0)
+#endif
+
/* The queue of sockets we've accepted */
static FDQueue csd_queue;
@@ -311,6 +320,13 @@
}
#elif defined(USE_MULTI_ACCEPT)
+
+#ifdef SINGLE_LISTEN_UNSERIALIZED_ACCEPT
+#define SAFE_ACCEPT(stmt) do {if(ap_listeners->next != NULL) {stmt;}}
while(0)
+#else
+#define SAFE_ACCEPT(stmt) do {stmt;} while(0)
+#endif
+
/*
* USE_MULTI_ACCEPT
* Worker threads do the accept and process the request.
1.73 +0 -7 apache-apr/pthreads/src/main/http_main.c
Index: http_main.c
===
RCS file: /home/cvs/apache-apr/pthreads/src/main/http_main.c,v
retrieving revision 1.72
retrieving revision 1.73
diff -u -u -r1.72 -r1.73
--- http_main.c 1999/04/15 20:01:40 1.72
+++ http_main.c 1999/04/17 04:25:56 1.73
@@ -416,13 +416,6 @@
}
}
-/* On some architectures it's safe to do unserialized accept()s in the single
- * Listen case. But it's never safe to do it in the case where there's
- * multiple Listen statements. Define SINGLE_LISTEN_UNSERIALIZED_ACCEPT
- * when it's safe in the single Listen case. We haven't defined this yet
- * for the hybrid server. ZZZ
- */
-
static void usage(char *bin)
{
char pad[MAX_STRING_LEN];
cvs commit: apache-apr/pthreads/src/main http_accept.c http_main.c
manoj 99/04/14 14:38:30
Modified:pthreads/src/include http_accept.h
pthreads/src/main http_accept.c http_main.c
Log:
Some tweaking of our http_accept modularization. A call is added to
perform any initialization needed in the parent. With this, we can take
all knowledge about accept serialization out of http_main.c. Also, the
function names were changed as a result of this addition and to keep the
difference between "request" and "connection" straight.
accept_parent_init (NEW)
init_accept -> accept_child_init
start_accepting_requests -> start_accepting_connections
get_request -> get_connection
stop_accepting_requests -> stop_accepting_connections
Revision ChangesPath
1.3 +5 -13 apache-apr/pthreads/src/include/http_accept.h
Index: http_accept.h
===
RCS file: /home/cvs/apache-apr/pthreads/src/include/http_accept.h,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -u -r1.2 -r1.3
--- http_accept.h 1999/04/14 21:03:18 1.2
+++ http_accept.h 1999/04/14 21:38:28 1.3
@@ -79,19 +79,11 @@
#define USE_ACCEPT_QUEUE
/*#define USE_MULTI_ACCEPT*/
-#if defined (USE_ACCEPT_QUEUE)
-void init_accept(pool*, int, int);
-void start_accepting_requests(int);
-int get_request(struct sockaddr *);
-void stop_accepting_requests(pool*);
-
-#elif defined (USE_MULTI_ACCEPT)
-void init_accept(pool*,int, int);
-void start_accepting_requests(int);
-int get_request(struct sockaddr *);
-void stop_accepting_requests(pool *);
-#endif
-
+void accept_parent_init(pool*);
+void accept_child_init(pool*, int, int);
+void start_accepting_connections(int);
+int get_connection(struct sockaddr *);
+void stop_accepting_connections(pool*);
#ifdef __cplusplus
}
1.5 +17 -8 apache-apr/pthreads/src/main/http_accept.c
Index: http_accept.c
===
RCS file: /home/cvs/apache-apr/pthreads/src/main/http_accept.c,v
retrieving revision 1.4
retrieving revision 1.5
diff -u -u -r1.4 -r1.5
--- http_accept.c 1999/04/14 21:03:26 1.4
+++ http_accept.c 1999/04/14 21:38:28 1.5
@@ -181,6 +181,11 @@
}
}
+void accept_parent_init(pool *pconf)
+{
+SAFE_ACCEPT(accept_mutex_init(pconf));
+}
+
/*
* Description:
* Do any setup or initialization required before worker threads begin
@@ -191,7 +196,7 @@
* 3. Pass in server_conf?
* 4. Simply access the globals (yech...)
*/
-void init_accept(pool* pchild,
+void accept_child_init(pool* pchild,
int worker_threads_per_child,
int acceptor_threads_per_child)
{
@@ -202,7 +207,7 @@
}
-void start_accepting_requests(int my_child_num)
+void start_accepting_connections(int my_child_num)
{
proc_info *my_info;
pthread_t thread;
@@ -275,7 +280,7 @@
accept_thread(my_info);
}
-int get_request(struct sockaddr *sa_client)
+int get_connection(struct sockaddr *sa_client)
{
int csd = -1;
int block_if_empty = 1;
@@ -295,7 +300,7 @@
return csd;
}
-void stop_accepting_requests(pool* pconf)
+void stop_accepting_connections(pool* pconf)
{
requests_this_child = 0;
/* The two functions to get all of our other threads to die off. */
@@ -313,8 +318,12 @@
static int num_listenfds;
static struct pollfd *listenfds;
+void accept_parent_init(pool *pconf)
+{
+SAFE_ACCEPT(accept_mutex_init(pconf));
+}
-void init_accept(pool* pchild,
+void accept_child_init(pool* pchild,
int worker_threads_per_child,
int acceptors_per_child)
{
@@ -336,10 +345,10 @@
}
}
-void start_accepting_requests(int my_child_num)
+void start_accepting_connections(int my_child_num)
{
}
-int get_request(struct sockaddr *sa_client)
+int get_connection(struct sockaddr *sa_client)
{
int csd = -1;
int sd;
@@ -446,7 +455,7 @@
return -1;
}
-void stop_accepting_requests(pool* pconf)
+void stop_accepting_connections(pool* pconf)
{
listen_rec *lr;
1.70 +5 -9 apache-apr/pthreads/src/main/http_main.c
Index: http_main.c
===
RCS file: /home/cvs/apache-apr/pthreads/src/main/http_main.c,v
retrieving revision 1.69
retrieving revision 1.70
diff -u -u -r1.69 -r1.70
--- http_main.c 1999/04/14 21:03:29 1.69
+++ http_main.c 1999/04/14 21:38:29 1.70
@@ -92,9 +92,6 @@
#include "util_script.h" /* to force util_script.c linking */
#include "util_uri.h"
#include "scoreboard.h"
-/* XXX - the accept_mutex_init call should be moved to http_accept.c. Until
- * that...
