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mm/hexagon: Use general page fault accounting

PATCH Superseded Peter Xu 2 participants 2 messages Jun 30, 2020

Subsystems (2)
Memory management Qualcomm hexagon architecture

v4 of 5 Superseded Latest is v5 →

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Peter Xu

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#0 lore raw

PATCH v4 7/26 mm/hexagon: Use general page fault accounting

Use the general page fault accounting by passing regs into handle_mm_fault(). It naturally solve the issue of multiple page fault accounting when page fault retry happened.

Add the missing PERF_COUNT_SW_PAGE_FAULTS perf events too. Note, the other two perf events (PERF_COUNT_SW_PAGE_FAULTS_[MAJ|MIN]) were done in handle_mm_fault().

CC Brian Cain <[email protected]>
CC [email protected]
Signed-off-by Peter Xu <[email protected]>
---
 arch/hexagon/mm/vm_fault.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)
arch/hexagon/mm/vm_fault.c +4 -5
index f12f330e7946..ef32c5a84ff3 100644
@@ -18,6 +18,7 @@
 #include <linux/signal.h>
 #include <linux/extable.h>
 #include <linux/hardirq.h>
+#include <linux/perf_event.h>
 
 /*
  * Decode of hardware exception sends us to one of several

@@ -53,6 +54,8 @@ void do_page_fault(unsigned long address, long cause, struct pt_regs *regs)
 
 	if (user_mode(regs))
 		flags |= FAULT_FLAG_USER;
+
+	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 retry:
 	mmap_read_lock(mm);
 	vma = find_vma(mm, address);

@@ -88,7 +91,7 @@ void do_page_fault(unsigned long address, long cause, struct pt_regs *regs)
 		break;
 	}
 
-	fault = handle_mm_fault(vma, address, flags, NULL);
+	fault = handle_mm_fault(vma, address, flags, regs);
 
 	if (fault_signal_pending(fault, regs))
 		return;

@@ -96,10 +99,6 @@ void do_page_fault(unsigned long address, long cause, struct pt_regs *regs)
 	/* The most common case -- we are done. */
 	if (likely(!(fault & VM_FAULT_ERROR))) {
 		if (flags & FAULT_FLAG_ALLOW_RETRY) {
-			if (fault & VM_FAULT_MAJOR)
-				current->maj_flt++;
-			else
-				current->min_flt++;
 			if (fault & VM_FAULT_RETRY) {
 				flags |= FAULT_FLAG_TRIED;
 				goto retry;
Signature · 1 line
2.26.2
Acked-by on v4 7/26
#1 lore raw
Quoted 3 lines

-----Original Message-----
From: [email protected] <linux-hexagon-

...

Acked-by Brian Cain <[email protected]>
Quoted 53 lines
CC Brian Cain <[email protected]>
CC [email protected]
Signed-off-by Peter Xu <[email protected]>
---
 arch/hexagon/mm/vm_fault.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)
arch/hexagon/mm/vm_fault.c +1 -0
index f12f330e7946..ef32c5a84ff3 100644
@@ -18,6 +18,7 @@
 #include <linux/signal.h>
 #include <linux/extable.h>
 #include <linux/hardirq.h>
+#include <linux/perf_event.h>
 
 /*
  * Decode of hardware exception sends us to one of several @@ -53,6 +54,8

@@ void do_page_fault(unsigned long address, long cause, struct pt_regs *regs)

arch/hexagon/mm/vm_fault.c +3 -1
 	if (user_mode(regs))
 		flags |= FAULT_FLAG_USER;
+
+	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 retry:
 	mmap_read_lock(mm);
 	vma = find_vma(mm, address);

@@ -88,7 +91,7 @@ void do_page_fault(unsigned long address, long cause,
 struct pt_regs *regs)
 		break;
 	}
 
-	fault = handle_mm_fault(vma, address, flags, NULL);
+	fault = handle_mm_fault(vma, address, flags, regs);
 
 	if (fault_signal_pending(fault, regs))
arch/hexagon/mm/vm_fault.c +0 -4
 		return;

@@ -96,10 +99,6 @@ void do_page_fault(unsigned long address, long cause,
 struct pt_regs *regs)
 	/* The most common case -- we are done. */
 	if (likely(!(fault & VM_FAULT_ERROR))) {
 		if (flags & FAULT_FLAG_ALLOW_RETRY) {
-			if (fault & VM_FAULT_MAJOR)
-				current->maj_flt++;
-			else
-				current->min_flt++;
 			if (fault & VM_FAULT_RETRY) {
 				flags |= FAULT_FLAG_TRIED;

goto retry;
--
2.26.2