[PATCH V8 03/10] powerpc, perf: Re organize BHRB processing
Anshuman Khandual
khandual at linux.vnet.ibm.com
Mon Jun 8 21:38:24 AEST 2015
This patch cleans up some existing indentation problem in code and
re organizes the BHRB processing code with an helper function named
'update_branch_entry' making it more readable. This patch does not
change any functionality.
Signed-off-by: Anshuman Khandual <khandual at linux.vnet.ibm.com>
---
arch/powerpc/perf/core-book3s.c | 107 ++++++++++++++++++++--------------------
1 file changed, 54 insertions(+), 53 deletions(-)
diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
index ae61629..d10d2c1 100644
--- a/arch/powerpc/perf/core-book3s.c
+++ b/arch/powerpc/perf/core-book3s.c
@@ -412,11 +412,19 @@ static __u64 power_pmu_bhrb_to(u64 addr)
return target - (unsigned long)&instr + addr;
}
+void update_branch_entry(struct cpu_hw_events *cpuhw,
+ int index, u64 from, u64 to, int pred)
+{
+ cpuhw->bhrb_entries[index].from = from;
+ cpuhw->bhrb_entries[index].to = to;
+ cpuhw->bhrb_entries[index].mispred = pred;
+ cpuhw->bhrb_entries[index].predicted = ~pred;
+}
+
/* Processing BHRB entries */
static void power_pmu_bhrb_read(struct cpu_hw_events *cpuhw)
{
- u64 val;
- u64 addr;
+ u64 val, addr, tmp;
int r_index, u_index, pred;
r_index = 0;
@@ -427,63 +435,56 @@ static void power_pmu_bhrb_read(struct cpu_hw_events *cpuhw)
if (!val)
/* Terminal marker: End of valid BHRB entries */
break;
- else {
- addr = val & BHRB_EA;
- pred = val & BHRB_PREDICTION;
- if (!addr)
- /* invalid entry */
- continue;
+ addr = val & BHRB_EA;
+ pred = val & BHRB_PREDICTION;
+
+ if (!addr)
+ /* invalid entry */
+ continue;
- /* Branches are read most recent first (ie. mfbhrb 0 is
- * the most recent branch).
- * There are two types of valid entries:
- * 1) a target entry which is the to address of a
- * computed goto like a blr,bctr,btar. The next
- * entry read from the bhrb will be branch
- * corresponding to this target (ie. the actual
- * blr/bctr/btar instruction).
- * 2) a from address which is an actual branch. If a
- * target entry proceeds this, then this is the
- * matching branch for that target. If this is not
- * following a target entry, then this is a branch
- * where the target is given as an immediate field
- * in the instruction (ie. an i or b form branch).
- * In this case we need to read the instruction from
- * memory to determine the target/to address.
+ /* Branches are read most recent first (ie. mfbhrb 0 is
+ * the most recent branch).
+ * There are two types of valid entries:
+ * 1) a target entry which is the to address of a
+ * computed goto like a blr,bctr,btar. The next
+ * entry read from the bhrb will be branch
+ * corresponding to this target (ie. the actual
+ * blr/bctr/btar instruction).
+ * 2) a from address which is an actual branch. If a
+ * target entry proceeds this, then this is the
+ * matching branch for that target. If this is not
+ * following a target entry, then this is a branch
+ * where the target is given as an immediate field
+ * in the instruction (ie. an i or b form branch).
+ * In this case we need to read the instruction from
+ * memory to determine the target/to address.
+ */
+ if (val & BHRB_TARGET) {
+ /* Target branches use two entries
+ * (ie. computed gotos/XL form)
*/
+ tmp = addr;
+
+ /* Get from address in next entry */
+ val = read_bhrb(r_index++);
+ if (!val)
+ break;
+ addr = val & BHRB_EA;
if (val & BHRB_TARGET) {
- /* Target branches use two entries
- * (ie. computed gotos/XL form)
- */
- cpuhw->bhrb_entries[u_index].to = addr;
- cpuhw->bhrb_entries[u_index].mispred = pred;
- cpuhw->bhrb_entries[u_index].predicted = ~pred;
-
- /* Get from address in next entry */
- val = read_bhrb(r_index++);
- if (!val)
- break;
- addr = val & BHRB_EA;
- if (val & BHRB_TARGET) {
- /* Shouldn't have two targets in a
- row.. Reset index and try again */
- r_index--;
- addr = 0;
- }
- cpuhw->bhrb_entries[u_index].from = addr;
- } else {
- /* Branches to immediate field
- (ie I or B form) */
- cpuhw->bhrb_entries[u_index].from = addr;
- cpuhw->bhrb_entries[u_index].to =
- power_pmu_bhrb_to(addr);
- cpuhw->bhrb_entries[u_index].mispred = pred;
- cpuhw->bhrb_entries[u_index].predicted = ~pred;
+ /* Shouldn't have two targets in a
+ row.. Reset index and try again */
+ r_index--;
+ addr = 0;
}
- u_index++;
-
+ update_branch_entry(cpuhw, u_index, addr, tmp, pred);
+ } else {
+ /* Branches to immediate field
+ (ie I or B form) */
+ tmp = power_pmu_bhrb_to(addr);
+ update_branch_entry(cpuhw, u_index, addr, tmp, pred);
}
+ u_index++;
}
cpuhw->bhrb_stack.nr = u_index;
return;
--
2.1.0
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