1 /*
2  * (c) 2009 Alexander Warg <warg@os.inf.tu-dresden.de>
3  *     economic rights: Technische Universität Dresden (Germany)
4  *
5  * This file is part of TUD:OS and distributed under the terms of the
6  * GNU General Public License 2.
7  * Please see the COPYING-GPL-2 file for details.
8  */
9 #include "sched_proxy.h"
10 #include "globals.h"
11 #include "debug.h"
12 
13 #include <algorithm>
14 #include <l4/re/env>
15 #include <l4/sys/scheduler>
16 
17 //#include <cstdio>
18 
19 static
20 l4_sched_cpu_set_t
blow_up(l4_sched_cpu_set_t const & src,unsigned char gran)21 blow_up(l4_sched_cpu_set_t const &src, unsigned char gran)
22 {
23   l4_sched_cpu_set_t n;
24   gran &= sizeof(l4_umword_t) * 8 - 1;
25   unsigned char og = src.granularity() & (sizeof(l4_umword_t) * 8 - 1);
26   n.set(gran, src.offset() & (~0UL << og));
27   n.map = 0;
28   for (unsigned i = 0; i < sizeof(l4_umword_t) * 8; ++i)
29     if (src.map & (1UL << (i >> (og - gran))))
30       n.map |= 1UL << i;
31 
32   return n;
33 }
34 
35 static
operator &(l4_sched_cpu_set_t const & a,l4_sched_cpu_set_t const & b)36 l4_sched_cpu_set_t operator & (l4_sched_cpu_set_t const &a, l4_sched_cpu_set_t const &b)
37 {
38   l4_sched_cpu_set_t _a, _b;
39   unsigned char const ga = a.granularity() & (sizeof(l4_umword_t) * 8 - 1);
40   unsigned char const gb = b.granularity() & (sizeof(l4_umword_t) * 8 - 1);
41   if (ga < gb)
42     {
43       _b = blow_up(b, ga);
44       _a = a;
45     }
46   else if (ga == gb)
47     {
48       _a = a;
49       _b = b;
50     }
51   else
52     {
53       _a = blow_up(a, gb);
54       _b = b;
55     }
56 
57   long ofs_dif = _a.offset() - _b.offset();
58   long unsigned abs_ofs_dif;
59   if (ofs_dif < 0)
60     abs_ofs_dif = -ofs_dif;
61   else
62     abs_ofs_dif = ofs_dif;
63 
64   if (abs_ofs_dif >= sizeof(l4_umword_t) * 8)
65     return l4_sched_cpu_set(0, 0, 0);
66 
67   if (ofs_dif < 0)
68     {
69       _b.map &= (_a.map >> abs_ofs_dif);
70       return _b;
71     }
72   else
73     {
74       _a.map &= (_b.map >> abs_ofs_dif);
75       return _a;
76     }
77 }
78 
79 Sched_proxy::List Sched_proxy::_list;
80 
Sched_proxy()81 Sched_proxy::Sched_proxy() :
82   Icu(1, &_scheduler_irq),
83   _real_cpus(l4_sched_cpu_set(0, 0, 0)), _cpu_mask(_real_cpus),
84   _max_cpus(0),
85   _prio_offset(0), _prio_limit(0)
86 {
87   rescan_cpus();
88   _list.push_front(this);
89 }
90 
91 void
rescan_cpus()92 Sched_proxy::rescan_cpus()
93 {
94   l4_sched_cpu_set_t c;
95   l4_umword_t max = 0;
96   c.map = 0;
97   c.gran_offset = 0;
98 
99   int e = l4_error(L4Re::Env::env()->scheduler()->info(&max, &c));
100   if (e < 0)
101     return;
102 
103   _max_cpus = std::min<unsigned>(sizeof(l4_umword_t) * 8, max);
104   _real_cpus = c;
105 
106   _cpus = _real_cpus & _cpu_mask;
107 }
108 
109 int
info(l4_umword_t * cpu_max,l4_sched_cpu_set_t * cpus)110 Sched_proxy::info(l4_umword_t *cpu_max, l4_sched_cpu_set_t *cpus)
111 {
112   *cpu_max = _max_cpus;
113   unsigned char g = cpus->granularity() & (sizeof(l4_umword_t) * 8 - 1);
114   l4_umword_t offs = cpus->offset() & (~0UL << g);
115   if (offs >= _max_cpus)
116     return -L4_ERANGE;
117 
118   cpus->map = 0;
119   unsigned b = 0;
120   for (unsigned i = offs; i < _max_cpus && b < sizeof(l4_umword_t) * 8;)
121     {
122       if (_cpus.map & (1UL << i))
123 	cpus->map |= 1UL << b;
124 
125       ++i;
126 
127       if (!(i & ~(~0UL << g)))
128 	++b;
129     }
130 
131   return L4_EOK;
132 }
133 
134 
135 int
run_thread(L4::Cap<L4::Thread> thread,l4_sched_param_t const & sp)136 Sched_proxy::run_thread(L4::Cap<L4::Thread> thread, l4_sched_param_t const &sp)
137 {
138   l4_sched_param_t s = sp;
139   s.prio = std::min(sp.prio + _prio_offset, (l4_umword_t)_prio_limit);
140   s.affinity = sp.affinity & _cpus;
141   if (0)
142     {
143       printf("loader[%p] run_thread: o=%u scheduler affinity = %lx "
144              "sp.m=%lx sp.o=%u sp.g=%u\n",
145              this, _cpus.offset(), _cpus.map, sp.affinity.map,
146              sp.affinity.offset(), sp.affinity.granularity());
147       printf("loader[%p]                                      "
148              " s.m=%lx  s.o=%u  s.g=%u\n",
149              this, s.affinity.map, s.affinity.offset(),
150              s.affinity.granularity());
151     }
152   return l4_error(L4Re::Env::env()->scheduler()->run_thread(thread, s));
153 }
154 
155 int
idle_time(l4_sched_cpu_set_t const &,l4_kernel_clock_t &)156 Sched_proxy::idle_time(l4_sched_cpu_set_t const &, l4_kernel_clock_t &)
157 { return -L4_ENOSYS; }
158 
159 
160 L4::Cap<L4::Thread>
received_thread(L4::Ipc::Snd_fpage const & fp)161 Sched_proxy::received_thread(L4::Ipc::Snd_fpage const &fp)
162 {
163   if (!fp.cap_received())
164     return L4::Cap<L4::Thread>::Invalid;
165 
166   return L4::Cap<L4::Thread>(Rcv_cap << L4_CAP_SHIFT);
167 }
168 
169 void
restrict_cpus(l4_umword_t cpus)170 Sched_proxy::restrict_cpus(l4_umword_t cpus)
171 {
172   _cpu_mask = l4_sched_cpu_set(0, 0, cpus);
173   _cpus = _real_cpus & _cpu_mask;
174 }
175 
176 
177 class Cpu_hotplug_server :
178   public L4::Irqep_t<Cpu_hotplug_server, Moe::Server_object>
179 {
180 public:
handle_irq()181   void handle_irq()
182   {
183     for (auto i : Sched_proxy::_list)
184       {
185         i->rescan_cpus();
186         i->hotplug_event();
187       }
188   }
189 
Cpu_hotplug_server()190   Cpu_hotplug_server()
191   {
192     L4::Cap<L4::Irq> irq = object_pool.cap_alloc()->alloc<L4::Irq>();
193     if (!irq)
194       {
195         Err(Err::Fatal).printf("Could not allocate capability for CPU hotplug\n");
196         return;
197       }
198 
199     if (l4_error(L4::Cap<L4::Factory>(L4_BASE_FACTORY_CAP)->create(irq)) < 0)
200       {
201         Err(Err::Fatal).printf("Could not allocate IRQ for CPU hotplug\n");
202         return;
203       }
204 
205     if (l4_error(irq->bind_thread(L4::Cap<L4::Thread>(L4_BASE_THREAD_CAP), l4_umword_t(this))) < 0)
206       {
207         Err(Err::Fatal).printf("Could not attach to CPU hotplug IRQ\n");
208         return;
209       }
210 
211     if (l4_error(L4Re::Env::env()->scheduler()->bind(0, irq)) < 0)
212       {
213         Err(Err::Fatal).printf("Could not bind CPU hotplug IRQ to scheduler\n");
214         return;
215       }
216   }
217 };
218 
219 static Cpu_hotplug_server _cpu_hotplug_server;
220