Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / arch / x86 / events / core.c

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index d0efb5c..d31735f 100644 (file)
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -37,6 +37,7 @@
 #include <asm/timer.h>
 #include <asm/desc.h>
 #include <asm/ldt.h>
+#include <asm/unwind.h>
 
 #include "perf_event.h"
 
@@ -1201,6 +1202,9 @@ static int x86_pmu_add(struct perf_event *event, int flags)
         * If group events scheduling transaction was started,
         * skip the schedulability test here, it will be performed
         * at commit time (->commit_txn) as a whole.
+        *
+        * If commit fails, we'll call ->del() on all events
+        * for which ->add() was called.
         */
        if (cpuc->txn_flags & PERF_PMU_TXN_ADD)
                goto done_collect;
@@ -1223,6 +1227,14 @@ done_collect:
        cpuc->n_added += n - n0;
        cpuc->n_txn += n - n0;
 
+       if (x86_pmu.add) {
+               /*
+                * This is before x86_pmu_enable() will call x86_pmu_start(),
+                * so we enable LBRs before an event needs them etc..
+                */
+               x86_pmu.add(event);
+       }
+
        ret = 0;
 out:
        return ret;
@@ -1346,7 +1358,7 @@ static void x86_pmu_del(struct perf_event *event, int flags)
        event->hw.flags &= ~PERF_X86_EVENT_COMMITTED;
 
        /*
-        * If we're called during a txn, we don't need to do anything.
+        * If we're called during a txn, we only need to undo x86_pmu.add.
         * The events never got scheduled and ->cancel_txn will truncate
         * the event_list.
         *
@@ -1354,7 +1366,7 @@ static void x86_pmu_del(struct perf_event *event, int flags)
         * an event added during that same TXN.
         */
        if (cpuc->txn_flags & PERF_PMU_TXN_ADD)
-               return;
+               goto do_del;
 
        /*
         * Not a TXN, therefore cleanup properly.
@@ -1384,6 +1396,15 @@ static void x86_pmu_del(struct perf_event *event, int flags)
        --cpuc->n_events;
 
        perf_event_update_userpage(event);
+
+do_del:
+       if (x86_pmu.del) {
+               /*
+                * This is after x86_pmu_stop(); so we disable LBRs after any
+                * event can need them etc..
+                */
+               x86_pmu.del(event);
+       }
 }
 
 int x86_pmu_handle_irq(struct pt_regs *regs)
@@ -2247,39 +2268,26 @@ void arch_perf_update_userpage(struct perf_event *event,
        cyc2ns_read_end(data);
 }
 
-/*
- * callchain support
- */
-
-static int backtrace_stack(void *data, char *name)
-{
-       return 0;
-}
-
-static int backtrace_address(void *data, unsigned long addr, int reliable)
-{
-       struct perf_callchain_entry_ctx *entry = data;
-
-       return perf_callchain_store(entry, addr);
-}
-
-static const struct stacktrace_ops backtrace_ops = {
-       .stack                  = backtrace_stack,
-       .address                = backtrace_address,
-       .walk_stack             = print_context_stack_bp,
-};
-
 void
 perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs)
 {
+       struct unwind_state state;
+       unsigned long addr;
+
        if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
                /* TODO: We don't support guest os callchain now */
                return;
        }
 
-       perf_callchain_store(entry, regs->ip);
+       if (perf_callchain_store(entry, regs->ip))
+               return;
 
-       dump_trace(NULL, regs, NULL, 0, &backtrace_ops, entry);
+       for (unwind_start(&state, current, regs, NULL); !unwind_done(&state);
+            unwind_next_frame(&state)) {
+               addr = unwind_get_return_address(&state);
+               if (!addr || perf_callchain_store(entry, addr))
+                       return;
+       }
 }
 
 static inline int