Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756334AbcKWSpP (ORCPT ); Wed, 23 Nov 2016 13:45:15 -0500 Received: from mga09.intel.com ([134.134.136.24]:51500 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933961AbcKWSpM (ORCPT ); Wed, 23 Nov 2016 13:45:12 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,539,1473145200"; d="scan'208";a="904841874" From: Ross Zwisler To: linux-kernel@vger.kernel.org Cc: Ross Zwisler , Alexander Viro , Andrew Morton , Christoph Hellwig , Dan Williams , Dave Chinner , Ingo Molnar , Jan Kara , Matthew Wilcox , Steven Rostedt , linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nvdimm@ml01.01.org Subject: [PATCH 5/6] dax: add tracepoints to dax_pmd_load_hole() Date: Wed, 23 Nov 2016 11:44:21 -0700 Message-Id: <1479926662-21718-6-git-send-email-ross.zwisler@linux.intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1479926662-21718-1-git-send-email-ross.zwisler@linux.intel.com> References: <1479926662-21718-1-git-send-email-ross.zwisler@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3649 Lines: 113 Add tracepoints to dax_pmd_load_hole(), following the same logging conventions as the tracepoints in dax_iomap_pmd_fault(). Here is an example PMD fault showing the new tracepoints: read_big-1393 [007] .... 32.133809: dax_pmd_fault: shared mapping read address 0x10400000 vm_start 0x10200000 vm_end 0x10600000 pgoff 0x200 max_pgoff 0x1400 read_big-1393 [007] .... 32.134067: dax_pmd_load_hole: shared mapping read address 0x10400000 zero_page ffffea0002b98000 radix_entry 0x1e read_big-1393 [007] .... 32.134069: dax_pmd_fault_done: shared mapping read address 0x10400000 vm_start 0x10200000 vm_end 0x10600000 pgoff 0x200 max_pgoff 0x1400 NOPAGE Signed-off-by: Ross Zwisler --- fs/dax.c | 13 +++++++++---- include/trace/events/fs_dax.h | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 41 insertions(+), 4 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index 1aa7616..2824414 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -1269,32 +1269,37 @@ static int dax_pmd_load_hole(struct vm_area_struct *vma, pmd_t *pmd, struct address_space *mapping = vma->vm_file->f_mapping; unsigned long pmd_addr = address & PMD_MASK; struct page *zero_page; + void *ret = NULL; spinlock_t *ptl; pmd_t pmd_entry; - void *ret; zero_page = mm_get_huge_zero_page(vma->vm_mm); if (unlikely(!zero_page)) - return VM_FAULT_FALLBACK; + goto fallback; ret = dax_insert_mapping_entry(mapping, vmf, *entryp, 0, RADIX_DAX_PMD | RADIX_DAX_HZP); if (IS_ERR(ret)) - return VM_FAULT_FALLBACK; + goto fallback; *entryp = ret; ptl = pmd_lock(vma->vm_mm, pmd); if (!pmd_none(*pmd)) { spin_unlock(ptl); - return VM_FAULT_FALLBACK; + goto fallback; } pmd_entry = mk_pmd(zero_page, vma->vm_page_prot); pmd_entry = pmd_mkhuge(pmd_entry); set_pmd_at(vma->vm_mm, pmd_addr, pmd, pmd_entry); spin_unlock(ptl); + trace_dax_pmd_load_hole(vma, address, zero_page, ret); return VM_FAULT_NOPAGE; + +fallback: + trace_dax_pmd_load_hole_fallback(vma, address, zero_page, ret); + return VM_FAULT_FALLBACK; } int dax_iomap_pmd_fault(struct vm_area_struct *vma, unsigned long address, diff --git a/include/trace/events/fs_dax.h b/include/trace/events/fs_dax.h index f9ed4eb..8814b1a 100644 --- a/include/trace/events/fs_dax.h +++ b/include/trace/events/fs_dax.h @@ -54,6 +54,38 @@ DEFINE_EVENT(dax_pmd_fault_class, name, \ DEFINE_PMD_FAULT_EVENT(dax_pmd_fault); DEFINE_PMD_FAULT_EVENT(dax_pmd_fault_done); +DECLARE_EVENT_CLASS(dax_pmd_load_hole_class, + TP_PROTO(struct vm_area_struct *vma, unsigned long address, + struct page *zero_page, void *radix_entry), + TP_ARGS(vma, address, zero_page, radix_entry), + TP_STRUCT__entry( + __field(unsigned long, vm_flags) + __field(unsigned long, address) + __field(struct page *, zero_page) + __field(void *, radix_entry) + ), + TP_fast_assign( + __entry->vm_flags = vma->vm_flags; + __entry->address = address; + __entry->zero_page = zero_page; + __entry->radix_entry = radix_entry; + ), + TP_printk("%s mapping read address %#lx zero_page %p radix_entry %#lx", + __entry->vm_flags & VM_SHARED ? "shared" : "private", + __entry->address, + __entry->zero_page, + (unsigned long)__entry->radix_entry + ) +) + +#define DEFINE_PMD_LOAD_HOLE_EVENT(name) \ +DEFINE_EVENT(dax_pmd_load_hole_class, name, \ + TP_PROTO(struct vm_area_struct *vma, unsigned long address, \ + struct page *zero_page, void *radix_entry), \ + TP_ARGS(vma, address, zero_page, radix_entry)) + +DEFINE_PMD_LOAD_HOLE_EVENT(dax_pmd_load_hole); +DEFINE_PMD_LOAD_HOLE_EVENT(dax_pmd_load_hole_fallback); #endif /* _TRACE_FS_DAX_H */ -- 2.7.4