perf_counter: Change pctrl() behaviour

Instead of en/dis-abling all counters acting on a particular
task, en/dis- able all counters we created.

[ v2: fix crash on first counter enable ]

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090523163012.916937244@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

3 files changed, 15 insertions, 0 deletions

diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index d87247d2641f..353c0ac7723a 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -108,6 +108,15 @@ extern struct group_info init_groups;
 
 extern struct cred init_cred;
 
+#ifdef CONFIG_PERF_COUNTERS
+# define INIT_PERF_COUNTERS(tsk)                                        \
+        .perf_counter_mutex =                                           \
+                 __MUTEX_INITIALIZER(tsk.perf_counter_mutex),           \
+        .perf_counter_list = LIST_HEAD_INIT(tsk.perf_counter_list),
+#else
+# define INIT_PERF_COUNTERS(tsk)
+#endif
+
 /*
  *  INIT_TASK is used to set up the first task table, touch at
  * your own risk!. Base=0, limit=0x1fffff (=2MB)
@@ -171,6 +180,7 @@ extern struct cred init_cred;
         },                                                              \
         .dirties = INIT_PROP_LOCAL_SINGLE(dirties),                     \
         INIT_IDS                                                        \
+        INIT_PERF_COUNTERS(tsk)                                         \
         INIT_TRACE_IRQFLAGS                                             \
         INIT_LOCKDEP                                                    \
         INIT_FTRACE_GRAPH                                               \
diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index 4ab8050eb9e8..4159ee5940f8 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -469,6 +469,9 @@ struct perf_counter {
         int                             oncpu;
         int                             cpu;
 
+        struct list_head                owner_entry;
+        struct task_struct              *owner;
+
         /* mmap bits */
         struct mutex                    mmap_mutex;
         atomic_t                        mmap_count;
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 9714d450f417..bc9326dcdde1 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1389,6 +1389,8 @@ struct task_struct {
 #endif
 #ifdef CONFIG_PERF_COUNTERS
         struct perf_counter_context *perf_counter_ctxp;
+        struct mutex perf_counter_mutex;
+        struct list_head perf_counter_list;
 #endif
 #ifdef CONFIG_NUMA
         struct mempolicy *mempolicy;