]> git.saurik.com Git - apple/xnu.git/blobdiff - osfmk/kern/sched_average.c
xnu-2782.1.97.tar.gz
[apple/xnu.git] / osfmk / kern / sched_average.c
index 2be1fa5b4c01a960ff68a4d811640875c088c236..b3edb3d9cc77acd72e13418bb5f4dda6bb94282d 100644 (file)
@@ -1,14 +1,19 @@
 /*
- * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2007 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ * 
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
  * 
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
@@ -18,7 +23,7 @@
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * 
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /*
  * @OSF_COPYRIGHT@
 #include <kern/assert.h>
 #include <kern/processor.h>
 #include <kern/thread.h>
+#if CONFIG_TELEMETRY
+#include <kern/telemetry.h>
+#endif
        
 uint32_t       avenrun[3] = {0, 0, 0};
 uint32_t       mach_factor[3] = {0, 0, 0};
 
+#if defined(CONFIG_SCHED_TRADITIONAL)
 /*
  * Values are scaled by LOAD_SCALE, defined in processor_info.h
  */
@@ -82,104 +91,147 @@ static uint32_t           fract[3] = {
 #undef base
 #undef frac
 
+#endif /* CONFIG_SCHED_TRADITIONAL */
+
 static unsigned int            sched_nrun;
 
 typedef void   (*sched_avg_comp_t)(
                                        void                    *param);
 
-#define SCHED_AVG_SECS(n)      ((n) << SCHED_TICK_SHIFT)
-
 static struct sched_average {
        sched_avg_comp_t        comp;
-       void                            *param;
-       int                                     period;
-       int                                     tick;                   
+       void                    *param;
+       int                     period; /* in seconds */
+       uint64_t                deadline;
 } sched_average[] = {
-       { compute_averunnable, &sched_nrun, SCHED_AVG_SECS(5), 0 },
-       { compute_stack_target, NULL, SCHED_AVG_SECS(5), 1 },
+       { compute_averunnable, &sched_nrun, 5, 0 },
+       { compute_stack_target, NULL, 5, 1 },
+       { compute_memory_pressure, NULL, 1, 0 },
+       { compute_zone_gc_throttle, NULL, 60, 0 },
+       { compute_pageout_gc_throttle, NULL, 1, 0 },
+       { compute_pmap_gc_throttle, NULL, 60, 0 },
+#if CONFIG_TELEMETRY
+       { compute_telemetry, NULL, 1, 0 },
+#endif
        { NULL, NULL, 0, 0 }
 };
 
 typedef struct sched_average   *sched_average_t;
 
+/* The "stdelta" parameter represents the number of scheduler maintenance
+ * "ticks" that have elapsed since the last invocation, subject to
+ * integer division imprecision.
+ */
+
 void
-compute_averages(void)
+compute_averages(uint64_t stdelta)
 {
-       register processor_set_t        pset = &default_pset;
-       register int                            ncpus;
-       register int                            nthreads, nshared;
-       sched_average_t                         avg;
-       register uint32_t                       factor_now = 0;
-       register uint32_t                       average_now = 0;
-       register uint32_t                       load_now = 0;
-
-       if ((ncpus = pset->processor_count) > 0) {
-               /*
-                *      Retrieve counts, ignoring
-                *      the current thread.
-                */
-               nthreads = pset->run_count - 1;
-               nshared = pset->share_count;
-
-               /*
-                *      Load average and mach factor calculations for
-                *      those which ask about these things.
-                */
-               average_now = nthreads * LOAD_SCALE;
-
-               if (nthreads > ncpus)
-                       factor_now = (ncpus * LOAD_SCALE) / (nthreads + 1);
+       int                     ncpus, nthreads, nshared, nbackground, nshared_non_bg;
+       uint32_t                factor_now, average_now, load_now = 0, background_load_now = 0, combined_fgbg_load_now = 0;
+       sched_average_t         avg;
+       uint64_t                abstime, index;
+
+       /*
+        *      Retrieve counts, ignoring
+        *      the current thread.
+        */
+       ncpus = processor_avail_count;
+       nthreads = sched_run_count - 1;
+       nshared = sched_share_count;
+       nbackground = sched_background_count;
+
+       /*
+        *      Load average and mach factor calculations for
+        *      those which ask about these things.
+        */
+       average_now = nthreads * LOAD_SCALE;
+
+       if (nthreads > ncpus)
+               factor_now = (ncpus * LOAD_SCALE) / (nthreads + 1);
+       else
+               factor_now = (ncpus - nthreads) * LOAD_SCALE;
+
+       /* For those statistics that formerly relied on being recomputed
+        * on timer ticks, advance by the approximate number of corresponding
+        * elapsed intervals, thus compensating for potential idle intervals.
+        */
+       for (index = 0; index < stdelta; index++) {
+               sched_mach_factor = ((sched_mach_factor << 2) + factor_now) / 5;
+               sched_load_average = ((sched_load_average << 2) + average_now) / 5;
+       }
+       /*
+        * Compute the timeshare priority conversion factor based on loading.
+        * Because our counters may be incremented and accessed
+        * concurrently with respect to each other, we may have
+        * windows where the invariant nthreads >= nshared >= nbackground
+        * is broken, so truncate values in these cases.
+        */
+
+       if (nshared > nthreads)
+               nshared = nthreads;
+
+       if (nbackground > nshared)
+               nbackground = nshared;
+
+       nshared_non_bg = nshared - nbackground;
+
+       if (nshared_non_bg > ncpus) {
+               if (ncpus > 1)
+                       load_now = nshared_non_bg / ncpus;
                else
-                       factor_now = (ncpus - nthreads) * LOAD_SCALE;
-
-               pset->mach_factor =     ((pset->mach_factor << 2) + factor_now) / 5;
-               pset->load_average = ((pset->load_average << 2) + average_now) / 5;
-
-               /*
-                *      Compute the timeshare priority
-                *      conversion factor based on loading.
-                */
-               if (nshared > nthreads)
-                       nshared = nthreads;
-
-               if (nshared > ncpus) {
-                       if (ncpus > 1)
-                               load_now = nshared / ncpus;
-                       else
-                               load_now = nshared;
-
-                       if (load_now > NRQS - 1)
-                               load_now = NRQS - 1;
-               }
+                       load_now = nshared_non_bg;
 
-               /*
-                *      The conversion factor consists of
-                *      two components: a fixed value based
-                *      on the absolute time unit, and a
-                *      dynamic portion based on loading.
-                *
-                *      Zero loading results in a out of range
-                *      shift count.  Accumulated usage is ignored
-                *      during conversion and new usage deltas
-                *      are discarded.
-                */
-               pset->pri_shift = sched_pri_shift - sched_load_shifts[load_now];
+               if (load_now > NRQS - 1)
+                       load_now = NRQS - 1;
        }
-       else {
-               pset->mach_factor = pset->load_average = 0;
-               pset->pri_shift = INT8_MAX;
-               nthreads = pset->run_count;
+
+       if (nbackground > ncpus) {
+               if (ncpus > 1)
+                       background_load_now = nbackground / ncpus;
+               else
+                       background_load_now = nbackground;
+
+               if (background_load_now > NRQS - 1)
+                       background_load_now = NRQS - 1;
+       }
+
+       if (nshared > ncpus) {
+               if (ncpus > 1)
+                       combined_fgbg_load_now = nshared / ncpus;
+               else
+                       combined_fgbg_load_now = nshared;
+
+               if (combined_fgbg_load_now > NRQS - 1)
+                       combined_fgbg_load_now = NRQS - 1;
        }
 
        /*
         *      Sample total running threads.
         */
        sched_nrun = nthreads;
+       
+#if defined(CONFIG_SCHED_TRADITIONAL)
+
+       /*
+        *      The conversion factor consists of
+        *      two components: a fixed value based
+        *      on the absolute time unit, and a
+        *      dynamic portion based on loading.
+        *
+        *      Zero loading results in a out of range
+        *      shift count.  Accumulated usage is ignored
+        *      during conversion and new usage deltas
+        *      are discarded.
+        */
+       sched_pri_shift = sched_fixed_shift - sched_load_shifts[load_now];
+       sched_background_pri_shift = sched_fixed_shift - sched_load_shifts[background_load_now];
+       sched_combined_fgbg_pri_shift = sched_fixed_shift - sched_load_shifts[combined_fgbg_load_now];
 
        /*
         * Compute old-style Mach load averages.
         */
-       {
+
+       for (index = 0; index < stdelta; index++) {
                register int            i;
 
                for (i = 0; i < 3; i++) {
@@ -190,14 +242,24 @@ compute_averages(void)
                                                (average_now * (LOAD_SCALE - fract[i]))) / LOAD_SCALE;
                }
        }
+#endif /* CONFIG_SCHED_TRADITIONAL */
 
        /*
         *      Compute averages in other components.
         */
+       abstime = mach_absolute_time();
        for (avg = sched_average; avg->comp != NULL; ++avg) {
-               if (++avg->tick >= avg->period) {
-                       (*avg->comp)(avg->param);
-                       avg->tick = 0;
+               if (abstime >= avg->deadline) {
+                       uint64_t period_abs = (avg->period * sched_one_second_interval);
+                       uint64_t ninvokes = 1;
+
+                       ninvokes += (abstime - avg->deadline) / period_abs;
+                       ninvokes = MIN(ninvokes, SCHED_TICK_MAX_DELTA);
+
+                       for (index = 0; index < ninvokes; index++) {
+                               (*avg->comp)(avg->param);
+                       }
+                       avg->deadline = abstime + period_abs;
                }
        }
 }