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-rw-r--r--native/src/sharedres.cpp322
1 files changed, 3 insertions, 319 deletions
diff --git a/native/src/sharedres.cpp b/native/src/sharedres.cpp
index 935d20f..a3b4ed9 100644
--- a/native/src/sharedres.cpp
+++ b/native/src/sharedres.cpp
@@ -22,7 +22,7 @@
22 22
23#include "blocking.h" 23#include "blocking.h"
24 24
25static const unsigned int UNLIMITED = UINT_MAX; 25const unsigned int UNLIMITED = UINT_MAX;
26 26
27std::ostream& operator<<(std::ostream &os, const TaskInfo &ti) 27std::ostream& operator<<(std::ostream &os, const TaskInfo &ti)
28{ 28{
@@ -78,10 +78,8 @@ unsigned int RequestBound::get_max_num_requests(unsigned long interval) const
78 78
79// ****** non-exported helpers ******* 79// ****** non-exported helpers *******
80 80
81typedef std::vector<const TaskInfo*> Cluster;
82typedef std::vector<Cluster> Clusters;
83 81
84static void split_by_cluster(const ResourceSharingInfo& info, Clusters& clusters) 82void split_by_cluster(const ResourceSharingInfo& info, Clusters& clusters)
85{ 83{
86 foreach(info.get_tasks(), it) 84 foreach(info.get_tasks(), it)
87 { 85 {
@@ -111,7 +109,7 @@ void sort_by_priority(Clusters& clusters)
111} 109}
112 110
113 111
114static void split_by_resource(const ResourceSharingInfo& info, Resources& resources) 112void split_by_resource(const ResourceSharingInfo& info, Resources& resources)
115{ 113{
116 foreach(info.get_tasks(), it) 114 foreach(info.get_tasks(), it)
117 { 115 {
@@ -1720,317 +1718,3 @@ BlockingBounds* part_fmlp_bounds(const ResourceSharingInfo& info, bool preemptiv
1720 return _results; 1718 return _results;
1721} 1719}
1722 1720
1723// *************************** MPCP ******************************************
1724
1725
1726typedef std::vector<unsigned int> PriorityCeilings;
1727
1728static void determine_priority_ceilings(const Resources& resources,
1729 PriorityCeilings& ceilings)
1730{
1731 ceilings.reserve(resources.size());
1732
1733 foreach(resources, it)
1734 {
1735 unsigned int ceiling = UINT_MAX;
1736 const ContentionSet& cs = *it;
1737
1738 foreach(cs, jt)
1739 {
1740 const RequestBound* req = *jt;
1741 ceiling = std::min(ceiling, req->get_task()->get_priority());
1742 }
1743
1744 ceilings.push_back(ceiling);
1745 }
1746}
1747
1748typedef std::vector<unsigned long> ResponseTimes;
1749typedef std::vector<ResponseTimes> TaskResponseTimes;
1750typedef std::vector<TaskResponseTimes> ClusterResponseTimes;
1751
1752static unsigned long get_max_gcs_length(const TaskInfo* tsk,
1753 const PriorityCeilings& ceilings,
1754 unsigned int preempted_ceiling)
1755{
1756 unsigned long gcs_length = 0;
1757
1758 foreach(tsk->get_requests(), it)
1759 {
1760 unsigned int prio = ceilings[it->get_resource_id()];
1761 if (prio < preempted_ceiling)
1762 gcs_length = std::max(gcs_length,
1763 (unsigned long) it->get_request_length());
1764 }
1765
1766 return gcs_length;
1767}
1768
1769static void determine_gcs_response_times(const TaskInfo* tsk,
1770 const Cluster& cluster,
1771 const PriorityCeilings& ceilings,
1772 ResponseTimes& times)
1773{
1774 times.reserve(tsk->get_requests().size());
1775
1776 foreach(tsk->get_requests(), it)
1777 {
1778 unsigned long resp = it->get_request_length();
1779 unsigned int prio = ceilings[it->get_resource_id()];
1780
1781 // Equation (2) in LNR:09.
1782 // One request of each local gcs that can preempt our ceiling,
1783 // but at most one per task (since tasks are sequential).
1784
1785 foreach(cluster, jt)
1786 {
1787 const TaskInfo* t = *jt;
1788
1789 if (t != tsk)
1790 resp += get_max_gcs_length(t, ceilings, prio);
1791 }
1792
1793 times.push_back(resp);
1794 }
1795}
1796
1797static void determine_gcs_response_times(const Cluster& cluster,
1798 const PriorityCeilings& ceilings,
1799 TaskResponseTimes& times)
1800{
1801 times.reserve(cluster.size());
1802 foreach(cluster, it)
1803 {
1804 times.push_back(ResponseTimes());
1805 determine_gcs_response_times(*it, cluster, ceilings,
1806 times.back());
1807 }
1808}
1809
1810static void determine_gcs_response_times(const Clusters& clusters,
1811 const PriorityCeilings& ceilings,
1812 ClusterResponseTimes& times)
1813{
1814 times.reserve(clusters.size());
1815 foreach(clusters, it)
1816 {
1817 times.push_back(TaskResponseTimes());
1818 determine_gcs_response_times(*it, ceilings, times.back());
1819 }
1820}
1821
1822static unsigned long response_time_for(unsigned int res_id,
1823 unsigned long interval,
1824 const TaskInfo* tsk,
1825 const ResponseTimes& resp,
1826 bool multiple)
1827{
1828 const Requests& requests = tsk->get_requests();
1829 unsigned int i = 0;
1830
1831 for (i = 0; i < requests.size(); i++)
1832 if (requests[i].get_resource_id() == res_id)
1833 {
1834 if (multiple)
1835 {
1836 // Equation (3) in LNR:09.
1837 // How many jobs?
1838 unsigned long num_jobs;
1839 num_jobs = divide_with_ceil(interval, tsk->get_period());
1840 num_jobs += 1;
1841
1842 // Note: this may represent multiple gcs, so multiply.
1843 return num_jobs * resp[i] * requests[i].get_num_requests();
1844 }
1845 else
1846 // Just one request.
1847 return resp[i];
1848 }
1849 // if we get here, then the task does not access res_id
1850 return 0;
1851}
1852
1853static unsigned long mpcp_remote_blocking(unsigned int res_id,
1854 unsigned long interval,
1855 const TaskInfo* tsk,
1856 const Cluster& cluster,
1857 const TaskResponseTimes times,
1858 unsigned long& max_lower)
1859{
1860 unsigned int i;
1861 unsigned long blocking = 0;
1862
1863 // consider each task in cluster
1864 for (i = 0; i < cluster.size(); i++)
1865 {
1866 const TaskInfo* t = cluster[i];
1867 if (t != tsk)
1868 {
1869 if (t->get_priority() < tsk->get_priority())
1870 // This is a higher-priority task;
1871 // it can block multiple times.
1872 blocking += response_time_for(res_id, interval,
1873 t, times[i], true);
1874 else
1875 // This is a lower-priority task;
1876 // it can block only once.
1877 max_lower = std::max(max_lower,
1878 response_time_for(res_id, interval,
1879 t, times[i], false));
1880 }
1881 }
1882
1883 return blocking;
1884}
1885
1886static unsigned long mpcp_remote_blocking(unsigned int res_id,
1887 unsigned long interval,
1888 const TaskInfo* tsk,
1889 const Clusters& clusters,
1890 const ClusterResponseTimes times,
1891 unsigned long& max_lower)
1892{
1893 unsigned int i;
1894 unsigned long blocking;
1895
1896 max_lower = 0;
1897 blocking = 0;
1898
1899 for (i = 0; i < clusters.size(); i++)
1900 {
1901 blocking += mpcp_remote_blocking(res_id, interval,
1902 tsk, clusters[i], times[i],
1903 max_lower);
1904 }
1905 return blocking;
1906}
1907
1908static unsigned long mpcp_remote_blocking(unsigned int res_id,
1909 const TaskInfo* tsk,
1910 const Clusters& clusters,
1911 const ClusterResponseTimes times)
1912{
1913 unsigned long interval;
1914 unsigned long blocking = 1;
1915 unsigned long max_lower;
1916
1917 do
1918 {
1919 // last bound
1920 interval = blocking;
1921 // Bail out if it doesn't converge.
1922 if (interval > tsk->get_response())
1923 return UNLIMITED;
1924
1925 blocking = mpcp_remote_blocking(res_id, interval,
1926 tsk, clusters, times,
1927 max_lower);
1928
1929 // Account for the maximum lower-priority gcs
1930 // that could get in the way.
1931 blocking += max_lower;
1932
1933 // Loop until it converges.
1934 } while ( interval != blocking );
1935
1936 return blocking;
1937}
1938
1939static unsigned long mpcp_remote_blocking(const TaskInfo* tsk,
1940 const Clusters& clusters,
1941 const ClusterResponseTimes times)
1942{
1943 unsigned long blocking = 0;
1944
1945
1946 const Requests& requests = tsk->get_requests();
1947 unsigned int i = 0;
1948
1949 for (i = 0; i < requests.size(); i++)
1950 {
1951 unsigned int b;
1952 b = mpcp_remote_blocking(requests[i].get_resource_id(),
1953 tsk, clusters, times);
1954 if (b != UNLIMITED)
1955 // may represent multiple, multiply accordingly
1956 blocking += b * requests[i].get_num_requests();
1957 else
1958 // bail out if it didn't converge
1959 return b;
1960 }
1961
1962 return blocking;
1963}
1964
1965static unsigned long mpcp_arrival_blocking(const TaskInfo* tsk,
1966 const Cluster& cluster,
1967 bool virtual_spinning)
1968{
1969 unsigned int prio = tsk->get_priority();
1970 unsigned int blocking = 0;
1971 unsigned int i;
1972
1973 for (i = 0; i < cluster.size(); i++)
1974 if (cluster[i] != tsk && cluster[i]->get_priority() >= prio)
1975 blocking += cluster[i]->get_max_request_length();
1976
1977 if (virtual_spinning)
1978 // Equation (4) in LNR:09.
1979 return blocking;
1980 else
1981 // Equation (1) in LNR:09.
1982 return blocking * tsk->get_num_arrivals();
1983}
1984
1985BlockingBounds* mpcp_bounds(const ResourceSharingInfo& info,
1986 bool use_virtual_spinning)
1987{
1988 Resources resources;
1989 Clusters clusters;
1990
1991 split_by_resource(info, resources);
1992 split_by_cluster(info, clusters);
1993
1994 // 2) Determine priority ceiling for each request.
1995 PriorityCeilings gc;
1996 determine_priority_ceilings(resources, gc);
1997
1998
1999 // 3) For each request, determine response time. This only depends on the
2000 // priority ceiling for each request.
2001 ClusterResponseTimes responses;
2002 determine_gcs_response_times(clusters, gc, responses);
2003
2004 unsigned int i;
2005
2006 BlockingBounds* _results = new BlockingBounds(info);
2007 BlockingBounds& results = *_results;
2008
2009 for (i = 0; i < info.get_tasks().size(); i++)
2010 {
2011 const TaskInfo& tsk = info.get_tasks()[i];
2012
2013 unsigned long remote, local = 0;
2014
2015 // 4) Determine remote blocking for each request. This depends on the
2016 // response times for each remote request.
2017 remote = mpcp_remote_blocking(&tsk, clusters, responses);
2018
2019 // 5) Determine arrival blocking for each task.
2020 if (remote != UNLIMITED)
2021 local = mpcp_arrival_blocking(&tsk, clusters[tsk.get_cluster()],
2022 use_virtual_spinning);
2023
2024 // 6) Sum up blocking: remote blocking + arrival blocking.
2025 results[i].total_length = remote + local;
2026
2027
2028 Interference inf;
2029 inf.total_length = remote;
2030 results.set_remote_blocking(i, inf);
2031 }
2032
2033 return _results;
2034}
2035
2036