linux-kernel - [PATCH v4 15/26] mm/parisc: Use general page fault accounting

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-Id: <20200630204540.39197-1-peterx@redhat.com>
Date:   Tue, 30 Jun 2020 16:45:40 -0400
From:   Peter Xu <peterx@...hat.com>
To:     linux-mm@...ck.org, linux-kernel@...r.kernel.org
Cc:     Andrew Morton <akpm@...ux-foundation.org>, peterx@...hat.com,
        John Hubbard <jhubbard@...dia.com>,
        Michael Ellerman <mpe@...erman.id.au>,
        Gerald Schaefer <gerald.schaefer@...ibm.com>,
        Andrea Arcangeli <aarcange@...hat.com>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Will Deacon <will@...nel.org>,
        "James E . J . Bottomley" <James.Bottomley@...senPartnership.com>,
        Helge Deller <deller@....de>, linux-parisc@...r.kernel.org
Subject: [PATCH v4 15/26] mm/parisc: 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: James E.J. Bottomley <James.Bottomley@...senPartnership.com>
CC: Helge Deller <deller@....de>
CC: linux-parisc@...r.kernel.org
Signed-off-by: Peter Xu <peterx@...hat.com>
---
 arch/parisc/mm/fault.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c
index e32d06928c24..4bfe2da9fbe3 100644
--- a/arch/parisc/mm/fault.c
+++ b/arch/parisc/mm/fault.c
@@ -18,6 +18,7 @@
 #include <linux/extable.h>
 #include <linux/uaccess.h>
 #include <linux/hugetlb.h>
+#include <linux/perf_event.h>
 
 #include <asm/traps.h>
 
@@ -281,6 +282,7 @@ void do_page_fault(struct pt_regs *regs, unsigned long code,
 	acc_type = parisc_acctyp(code, regs->iir);
 	if (acc_type & VM_WRITE)
 		flags |= FAULT_FLAG_WRITE;
+	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 retry:
 	mmap_read_lock(mm);
 	vma = find_vma_prev(mm, address, &prev_vma);
@@ -302,7 +304,7 @@ void do_page_fault(struct pt_regs *regs, unsigned long code,
 	 * fault.
 	 */
 
-	fault = handle_mm_fault(vma, address, flags, NULL);
+	fault = handle_mm_fault(vma, address, flags, regs);
 
 	if (fault_signal_pending(fault, regs))
 		return;
@@ -323,10 +325,6 @@ void do_page_fault(struct pt_regs *regs, unsigned long code,
 		BUG();
 	}
 	if (flags & FAULT_FLAG_ALLOW_RETRY) {
-		if (fault & VM_FAULT_MAJOR)
-			current->maj_flt++;
-		else
-			current->min_flt++;
 		if (fault & VM_FAULT_RETRY) {
 			/*
 			 * No need to mmap_read_unlock(mm) as we would
-- 
2.26.2