Linus,

Please pull the latest perf-urgent-for-linus git tree from:

   git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 
perf-urgent-for-linus

   # HEAD: f67b15037a7a50c57f72e69a6d59941ad90a0f0f perf/hwbp: Simplify the 
perf-hwbp code, fix documentation

Two fixlets.

 Thanks,

        Ingo

------------------>
Linus Torvalds (1):
      perf/hwbp: Simplify the perf-hwbp code, fix documentation

Stephane Eranian (1):
      perf/x86/intel: Fix linear IP of PEBS real_ip on Haswell and later CPUs


 arch/x86/events/intel/ds.c    | 25 +++++++++++++++++--------
 kernel/events/hw_breakpoint.c | 30 +++++++-----------------------
 2 files changed, 24 insertions(+), 31 deletions(-)

diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index d8015235ba76..5e526c54247e 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -1153,6 +1153,7 @@ static void setup_pebs_sample_data(struct perf_event 
*event,
        if (pebs == NULL)
                return;
 
+       regs->flags &= ~PERF_EFLAGS_EXACT;
        sample_type = event->attr.sample_type;
        dsrc = sample_type & PERF_SAMPLE_DATA_SRC;
 
@@ -1197,7 +1198,6 @@ static void setup_pebs_sample_data(struct perf_event 
*event,
         */
        *regs = *iregs;
        regs->flags = pebs->flags;
-       set_linear_ip(regs, pebs->ip);
 
        if (sample_type & PERF_SAMPLE_REGS_INTR) {
                regs->ax = pebs->ax;
@@ -1233,13 +1233,22 @@ static void setup_pebs_sample_data(struct perf_event 
*event,
 #endif
        }
 
-       if (event->attr.precise_ip > 1 && x86_pmu.intel_cap.pebs_format >= 2) {
-               regs->ip = pebs->real_ip;
-               regs->flags |= PERF_EFLAGS_EXACT;
-       } else if (event->attr.precise_ip > 1 && intel_pmu_pebs_fixup_ip(regs))
-               regs->flags |= PERF_EFLAGS_EXACT;
-       else
-               regs->flags &= ~PERF_EFLAGS_EXACT;
+       if (event->attr.precise_ip > 1) {
+               /* Haswell and later have the eventing IP, so use it: */
+               if (x86_pmu.intel_cap.pebs_format >= 2) {
+                       set_linear_ip(regs, pebs->real_ip);
+                       regs->flags |= PERF_EFLAGS_EXACT;
+               } else {
+                       /* Otherwise use PEBS off-by-1 IP: */
+                       set_linear_ip(regs, pebs->ip);
+
+                       /* ... and try to fix it up using the LBR entries: */
+                       if (intel_pmu_pebs_fixup_ip(regs))
+                               regs->flags |= PERF_EFLAGS_EXACT;
+               }
+       } else
+               set_linear_ip(regs, pebs->ip);
+
 
        if ((sample_type & (PERF_SAMPLE_ADDR | PERF_SAMPLE_PHYS_ADDR)) &&
            x86_pmu.intel_cap.pebs_format >= 1)
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index 3f8cb1e14588..253ae2da13c3 100644
--- a/kernel/events/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
@@ -427,16 +427,9 @@ EXPORT_SYMBOL_GPL(register_user_hw_breakpoint);
  * modify_user_hw_breakpoint - modify a user-space hardware breakpoint
  * @bp: the breakpoint structure to modify
  * @attr: new breakpoint attributes
- * @triggered: callback to trigger when we hit the breakpoint
- * @tsk: pointer to 'task_struct' of the process to which the address belongs
  */
 int modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr 
*attr)
 {
-       u64 old_addr = bp->attr.bp_addr;
-       u64 old_len = bp->attr.bp_len;
-       int old_type = bp->attr.bp_type;
-       int err = 0;
-
        /*
         * modify_user_hw_breakpoint can be invoked with IRQs disabled and 
hence it
         * will not be possible to raise IPIs that invoke __perf_event_disable.
@@ -451,27 +444,18 @@ int modify_user_hw_breakpoint(struct perf_event *bp, 
struct perf_event_attr *att
        bp->attr.bp_addr = attr->bp_addr;
        bp->attr.bp_type = attr->bp_type;
        bp->attr.bp_len = attr->bp_len;
+       bp->attr.disabled = 1;
 
-       if (attr->disabled)
-               goto end;
-
-       err = validate_hw_breakpoint(bp);
-       if (!err)
-               perf_event_enable(bp);
+       if (!attr->disabled) {
+               int err = validate_hw_breakpoint(bp);
 
-       if (err) {
-               bp->attr.bp_addr = old_addr;
-               bp->attr.bp_type = old_type;
-               bp->attr.bp_len = old_len;
-               if (!bp->attr.disabled)
-                       perf_event_enable(bp);
+               if (err)
+                       return err;
 
-               return err;
+               perf_event_enable(bp);
+               bp->attr.disabled = 0;
        }
 
-end:
-       bp->attr.disabled = attr->disabled;
-
        return 0;
 }
 EXPORT_SYMBOL_GPL(modify_user_hw_breakpoint);

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