Remove non-smart scheduler. Don't require setitimer.

This allows the server to call GetTimeInMillis() after each request is
processed to avoid needing setitimer. -dumbSched now turns off the
setitimer.

Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Keith Packard <keithp@keithp.com>

7 files changed, 45 insertions, 48 deletions

diff --git a/configure.ac b/configure.ac
index 14a5bb8dd..2e38efac3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -218,7 +218,7 @@ AC_SUBST(DLOPEN_LIBS)
 dnl Checks for library functions.
 AC_CHECK_FUNCS([backtrace ffs geteuid getuid issetugid getresuid \
 	getdtablesize getifaddrs getpeereid getpeerucred getprogname getzoneid \
-	mmap seteuid shmctl64 strncasecmp vasprintf vsnprintf walkcontext])
+	mmap seteuid shmctl64 strncasecmp vasprintf vsnprintf walkcontext setitimer])
 AC_REPLACE_FUNCS([reallocarray strcasecmp strcasestr strlcat strlcpy strndup])
 
 AC_CHECK_DECLS([program_invocation_short_name], [], [], [[#include <errno.h>]])
diff --git a/dix/dispatch.c b/dix/dispatch.c
index 2c201245a..53032dc64 100644
--- a/dix/dispatch.c
+++ b/dix/dispatch.c
@@ -222,11 +222,11 @@ UpdateCurrentTimeIf(void)
 #define SMART_SCHEDULE_DEFAULT_INTERVAL	5
 #define SMART_SCHEDULE_MAX_SLICE	15
 
-#if defined(WIN32) && !defined(__CYGWIN__)
-Bool SmartScheduleDisable = TRUE;
-#else
-Bool SmartScheduleDisable = FALSE;
+#ifdef HAVE_SETITIMER
+#define SMART_SCHEDULE_DEFAULT_SIGNAL_ENABLE HAVE_SETITIMER
+Bool SmartScheduleSignalEnable = SMART_SCHEDULE_DEFAULT_SIGNAL_ENABLE;
 #endif
+
 long SmartScheduleSlice = SMART_SCHEDULE_DEFAULT_INTERVAL;
 long SmartScheduleInterval = SMART_SCHEDULE_DEFAULT_INTERVAL;
 long SmartScheduleMaxSlice = SMART_SCHEDULE_MAX_SLICE;
@@ -358,7 +358,7 @@ Dispatch(void)
 
         nready = WaitForSomething(clientReady);
 
-        if (nready && !SmartScheduleDisable) {
+        if (nready) {
             clientReady[0] = SmartScheduleClient(clientReady, nready);
             nready = 1;
         }
@@ -386,8 +386,8 @@ Dispatch(void)
                     ProcessInputEvents();
 
                 FlushIfCriticalOutputPending();
-                if (!SmartScheduleDisable &&
-                    (SmartScheduleTime - start_tick) >= SmartScheduleSlice) {
+                if ((SmartScheduleTime - start_tick) >= SmartScheduleSlice)
+                {
                     /* Penalize clients which consume ticks */
                     if (client->smart_priority > SMART_MIN_PRIORITY)
                         client->smart_priority--;
@@ -431,6 +431,9 @@ Dispatch(void)
                             (*client->requestVector[client->majorOp]) (client);
                     XaceHookAuditEnd(client, result);
                 }
+                if (!SmartScheduleSignalEnable)
+                    SmartScheduleTime = GetTimeInMillis();
+
 #ifdef XSERVER_DTRACE
                 if (XSERVER_REQUEST_DONE_ENABLED())
                     XSERVER_REQUEST_DONE(LookupMajorName(client->majorOp),
diff --git a/include/dix-config.h.in b/include/dix-config.h.in
index 112ab952f..940d2b7e2 100644
--- a/include/dix-config.h.in
+++ b/include/dix-config.h.in
@@ -518,4 +518,7 @@
 /* Define if no local socket credentials interface exists */
 #undef NO_LOCAL_CLIENT_CRED
 
+/* Have setitimer support */
+#undef HAVE_SETITIMER
+
 #endif /* _DIX_CONFIG_H_ */
diff --git a/include/dixstruct.h b/include/dixstruct.h
index 757506623..8e70ae1fa 100644
--- a/include/dixstruct.h
+++ b/include/dixstruct.h
@@ -130,7 +130,11 @@ extern long SmartScheduleTime;
 extern long SmartScheduleInterval;
 extern long SmartScheduleSlice;
 extern long SmartScheduleMaxSlice;
-extern Bool SmartScheduleDisable;
+#if HAVE_SETITIMER
+extern Bool SmartScheduleSignalEnable;
+#else
+#define SmartScheduleSignalEnable FALSE
+#endif
 extern void SmartScheduleStartTimer(void);
 extern void SmartScheduleStopTimer(void);
 
diff --git a/os/WaitFor.c b/os/WaitFor.c
index 993c14e52..732543086 100644
--- a/os/WaitFor.c
+++ b/os/WaitFor.c
@@ -175,16 +175,10 @@ WaitForSomething(int *pClientsReady)
         if (workQueue)
             ProcessWorkQueue();
         if (XFD_ANYSET(&ClientsWithInput)) {
-            if (!SmartScheduleDisable) {
-                someReady = TRUE;
-                waittime.tv_sec = 0;
-                waittime.tv_usec = 0;
-                wt = &waittime;
-            }
-            else {
-                XFD_COPYSET(&ClientsWithInput, &clientsReadable);
-                break;
-            }
+            someReady = TRUE;
+            waittime.tv_sec = 0;
+            waittime.tv_usec = 0;
+            wt = &waittime;
         }
         if (someReady) {
             XFD_COPYSET(&AllSockets, &LastSelectMask);
diff --git a/os/io.c b/os/io.c
index 55644eaf3..971fdc951 100644
--- a/os/io.c
+++ b/os/io.c
@@ -462,23 +462,14 @@ ReadRequestFromClient(ClientPtr client)
             )
             FD_SET(fd, &ClientsWithInput);
         else {
-            if (!SmartScheduleDisable)
-                FD_CLR(fd, &ClientsWithInput);
-            else
-                YieldControlNoInput(fd);
+            FD_CLR(fd, &ClientsWithInput);
         }
     }
     else {
         if (!gotnow)
             AvailableInput = oc;
-        if (!SmartScheduleDisable)
-            FD_CLR(fd, &ClientsWithInput);
-        else
-            YieldControlNoInput(fd);
+        FD_CLR(fd, &ClientsWithInput);
     }
-    if (SmartScheduleDisable)
-        if (++timesThisConnection >= MAX_TIMES_PER)
-            YieldControl();
     if (move_header) {
         request = (xReq *) oci->bufptr;
         oci->bufptr += (sizeof(xBigReq) - sizeof(xReq));
diff --git a/os/utils.c b/os/utils.c
index b45719e26..ef7a2cc21 100644
--- a/os/utils.c
+++ b/os/utils.c
@@ -71,7 +71,6 @@ __stdcall unsigned long GetTickCount(void);
 #if !defined(WIN32) || !defined(__MINGW32__)
 #include <sys/time.h>
 #include <sys/resource.h>
-# define SMART_SCHEDULE_POSSIBLE
 #endif
 #include "misc.h"
 #include <X11/X.h>
@@ -1005,10 +1004,11 @@ ProcessCommandLine(int argc, char *argv[])
             i = skip - 1;
         }
 #endif
-#ifdef SMART_SCHEDULE_POSSIBLE
+#if HAVE_SETITIMER
         else if (strcmp(argv[i], "-dumbSched") == 0) {
-            SmartScheduleDisable = TRUE;
+            SmartScheduleSignalEnable = FALSE;
         }
+#endif
         else if (strcmp(argv[i], "-schedInterval") == 0) {
             if (++i < argc) {
                 SmartScheduleInterval = atoi(argv[i]);
@@ -1024,7 +1024,6 @@ ProcessCommandLine(int argc, char *argv[])
             else
                 UseMsg();
         }
-#endif
         else if (strcmp(argv[i], "-render") == 0) {
             if (++i < argc) {
                 int policy = PictureParseCmapPolicy(argv[i]);
@@ -1208,10 +1207,10 @@ XNFstrdup(const char *s)
 void
 SmartScheduleStopTimer(void)
 {
-#ifdef SMART_SCHEDULE_POSSIBLE
+#if HAVE_SETITIMER
     struct itimerval timer;
 
-    if (SmartScheduleDisable)
+    if (!SmartScheduleSignalEnable)
         return;
     timer.it_interval.tv_sec = 0;
     timer.it_interval.tv_usec = 0;
@@ -1224,10 +1223,10 @@ SmartScheduleStopTimer(void)
 void
 SmartScheduleStartTimer(void)
 {
-#ifdef SMART_SCHEDULE_POSSIBLE
+#if HAVE_SETITIMER
     struct itimerval timer;
 
-    if (SmartScheduleDisable)
+    if (!SmartScheduleSignalEnable)
         return;
     timer.it_interval.tv_sec = 0;
     timer.it_interval.tv_usec = SmartScheduleInterval * 1000;
@@ -1237,6 +1236,7 @@ SmartScheduleStartTimer(void)
 #endif
 }
 
+#if HAVE_SETITIMER
 static void
 SmartScheduleTimer(int sig)
 {
@@ -1247,10 +1247,9 @@ static int
 SmartScheduleEnable(void)
 {
     int ret = 0;
-#ifdef SMART_SCHEDULE_POSSIBLE
     struct sigaction act;
 
-    if (SmartScheduleDisable)
+    if (!SmartScheduleSignalEnable)
         return 0;
 
     memset((char *) &act, 0, sizeof(struct sigaction));
@@ -1261,7 +1260,6 @@ SmartScheduleEnable(void)
     sigemptyset(&act.sa_mask);
     sigaddset(&act.sa_mask, SIGALRM);
     ret = sigaction(SIGALRM, &act, 0);
-#endif
     return ret;
 }
 
@@ -1269,10 +1267,9 @@ static int
 SmartSchedulePause(void)
 {
     int ret = 0;
-#ifdef SMART_SCHEDULE_POSSIBLE
     struct sigaction act;
 
-    if (SmartScheduleDisable)
+    if (!SmartScheduleSignalEnable)
         return 0;
 
     memset((char *) &act, 0, sizeof(struct sigaction));
@@ -1280,20 +1277,19 @@ SmartSchedulePause(void)
     act.sa_handler = SIG_IGN;
     sigemptyset(&act.sa_mask);
     ret = sigaction(SIGALRM, &act, 0);
-#endif
     return ret;
 }
+#endif
 
 void
 SmartScheduleInit(void)
 {
-    if (SmartScheduleDisable)
-        return;
-
+#if HAVE_SETITIMER
     if (SmartScheduleEnable() < 0) {
         perror("sigaction for smart scheduler");
-        SmartScheduleDisable = TRUE;
+        SmartScheduleSignalEnable = FALSE;
     }
+#endif
 }
 
 #ifdef SIG_BLOCK
@@ -1490,6 +1486,7 @@ Popen(const char *command, const char *type)
     }
 
     /* Ignore the smart scheduler while this is going on */
+#if HAVE_SETITIMER
     if (SmartSchedulePause() < 0) {
         close(pdes[0]);
         close(pdes[1]);
@@ -1497,14 +1494,17 @@ Popen(const char *command, const char *type)
         perror("signal");
         return NULL;
     }
+#endif
 
     switch (pid = fork()) {
     case -1:                   /* error */
         close(pdes[0]);
         close(pdes[1]);
         free(cur);
+#if HAVE_SETITIMER
         if (SmartScheduleEnable() < 0)
             perror("signal");
+#endif
         return NULL;
     case 0:                    /* child */
         if (setgid(getgid()) == -1)
@@ -1678,10 +1678,12 @@ Pclose(void *iop)
     /* allow EINTR again */
     OsReleaseSignals();
 
+#if HAVE_SETITIMER
     if (SmartScheduleEnable() < 0) {
         perror("signal");
         return -1;
     }
+#endif
 
     return pid == -1 ? -1 : pstat;
 }