From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751520AbdBXVcQ (ORCPT ); Fri, 24 Feb 2017 16:32:16 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:54610 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751219AbdBXVbz (ORCPT ); Fri, 24 Feb 2017 16:31:55 -0500 Smtp-Origin-Hostprefix: devbig From: Shaohua Li Smtp-Origin-Hostname: devbig638.prn2.facebook.com To: , CC: , , , , , , , Smtp-Origin-Cluster: prn2c22 Subject: [PATCH V5 1/6] mm: delete unnecessary TTU_* flags Date: Fri, 24 Feb 2017 13:31:44 -0800 Message-ID: <4be3ea1bc56b26fd98a54d0a6f70bec63f6d8980.1487965799.git.shli@fb.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: References: X-FB-Internal: Safe MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-02-24_13:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Johannes pointed out TTU_LZFREE is unnecessary. It's true because we always have the flag set if we want to do an unmap. For cases we don't do an unmap, the TTU_LZFREE part of code should never run. Also the TTU_UNMAP is unnecessary. If no other flags set (for example, TTU_MIGRATION), an unmap is implied. The patch includes Johannes's cleanup and dead TTU_ACTION macro removal code Cc: Michal Hocko Cc: Hugh Dickins Cc: Rik van Riel Cc: Mel Gorman Cc: Andrew Morton Suggested-by: Johannes Weiner Acked-by: Johannes Weiner Acked-by: Minchan Kim Acked-by: Hillf Danton Signed-off-by: Shaohua Li --- include/linux/rmap.h | 22 +++++++++------------- mm/memory-failure.c | 2 +- mm/rmap.c | 2 +- mm/vmscan.c | 11 ++++------- 4 files changed, 15 insertions(+), 22 deletions(-) diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 8c89e90..7a39414 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -83,19 +83,17 @@ struct anon_vma_chain { }; enum ttu_flags { - TTU_UNMAP = 1, /* unmap mode */ - TTU_MIGRATION = 2, /* migration mode */ - TTU_MUNLOCK = 4, /* munlock mode */ - TTU_LZFREE = 8, /* lazy free mode */ - TTU_SPLIT_HUGE_PMD = 16, /* split huge PMD if any */ - - TTU_IGNORE_MLOCK = (1 << 8), /* ignore mlock */ - TTU_IGNORE_ACCESS = (1 << 9), /* don't age */ - TTU_IGNORE_HWPOISON = (1 << 10),/* corrupted page is recoverable */ - TTU_BATCH_FLUSH = (1 << 11), /* Batch TLB flushes where possible + TTU_MIGRATION = 0x1, /* migration mode */ + TTU_MUNLOCK = 0x2, /* munlock mode */ + + TTU_SPLIT_HUGE_PMD = 0x4, /* split huge PMD if any */ + TTU_IGNORE_MLOCK = 0x8, /* ignore mlock */ + TTU_IGNORE_ACCESS = 0x10, /* don't age */ + TTU_IGNORE_HWPOISON = 0x20, /* corrupted page is recoverable */ + TTU_BATCH_FLUSH = 0x40, /* Batch TLB flushes where possible * and caller guarantees they will * do a final flush if necessary */ - TTU_RMAP_LOCKED = (1 << 12) /* do not grab rmap lock: + TTU_RMAP_LOCKED = 0x80 /* do not grab rmap lock: * caller holds it */ }; @@ -193,8 +191,6 @@ static inline void page_dup_rmap(struct page *page, bool compound) int page_referenced(struct page *, int is_locked, struct mem_cgroup *memcg, unsigned long *vm_flags); -#define TTU_ACTION(x) ((x) & TTU_ACTION_MASK) - int try_to_unmap(struct page *, enum ttu_flags flags); /* Avoid racy checks */ diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 3d0f2fd..b78d080 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -906,7 +906,7 @@ EXPORT_SYMBOL_GPL(get_hwpoison_page); static int hwpoison_user_mappings(struct page *p, unsigned long pfn, int trapno, int flags, struct page **hpagep) { - enum ttu_flags ttu = TTU_UNMAP | TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS; + enum ttu_flags ttu = TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS; struct address_space *mapping; LIST_HEAD(tokill); int ret; diff --git a/mm/rmap.c b/mm/rmap.c index 8774791..96eb85c 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1418,7 +1418,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, */ VM_BUG_ON_PAGE(!PageSwapCache(page), page); - if (!PageDirty(page) && (flags & TTU_LZFREE)) { + if (!PageDirty(page)) { /* It's a freeable page by MADV_FREE */ dec_mm_counter(mm, MM_ANONPAGES); rp->lazyfreed++; diff --git a/mm/vmscan.c b/mm/vmscan.c index 26c3b40..68ea50d 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -971,7 +971,6 @@ static unsigned long shrink_page_list(struct list_head *page_list, int may_enter_fs; enum page_references references = PAGEREF_RECLAIM_CLEAN; bool dirty, writeback; - bool lazyfree = false; int ret = SWAP_SUCCESS; cond_resched(); @@ -1125,7 +1124,6 @@ static unsigned long shrink_page_list(struct list_head *page_list, goto keep_locked; if (!add_to_swap(page, page_list)) goto activate_locked; - lazyfree = true; may_enter_fs = 1; /* Adding to swap updated mapping */ @@ -1143,9 +1141,8 @@ static unsigned long shrink_page_list(struct list_head *page_list, * processes. Try to unmap it here. */ if (page_mapped(page) && mapping) { - switch (ret = try_to_unmap(page, lazyfree ? - (ttu_flags | TTU_BATCH_FLUSH | TTU_LZFREE) : - (ttu_flags | TTU_BATCH_FLUSH))) { + switch (ret = try_to_unmap(page, + ttu_flags | TTU_BATCH_FLUSH)) { case SWAP_FAIL: nr_unmap_fail++; goto activate_locked; @@ -1353,7 +1350,7 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, } ret = shrink_page_list(&clean_pages, zone->zone_pgdat, &sc, - TTU_UNMAP|TTU_IGNORE_ACCESS, NULL, true); + TTU_IGNORE_ACCESS, NULL, true); list_splice(&clean_pages, page_list); mod_node_page_state(zone->zone_pgdat, NR_ISOLATED_FILE, -ret); return ret; @@ -1760,7 +1757,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, if (nr_taken == 0) return 0; - nr_reclaimed = shrink_page_list(&page_list, pgdat, sc, TTU_UNMAP, + nr_reclaimed = shrink_page_list(&page_list, pgdat, sc, 0, &stat, false); spin_lock_irq(&pgdat->lru_lock); -- 2.9.3 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-f71.google.com (mail-it0-f71.google.com [209.85.214.71]) by kanga.kvack.org (Postfix) with ESMTP id E443D6B0389 for ; Fri, 24 Feb 2017 16:31:53 -0500 (EST) Received: by mail-it0-f71.google.com with SMTP id h10so8064204ith.2 for ; Fri, 24 Feb 2017 13:31:53 -0800 (PST) Received: from mx0a-00082601.pphosted.com (mx0b-00082601.pphosted.com. [67.231.153.30]) by mx.google.com with ESMTPS id o124si2733430itc.71.2017.02.24.13.31.53 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 24 Feb 2017 13:31:53 -0800 (PST) Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.16.0.20/8.16.0.20) with SMTP id v1OLMA6p031393 for ; Fri, 24 Feb 2017 13:31:52 -0800 Received: from mail.thefacebook.com ([199.201.64.23]) by m0001303.ppops.net with ESMTP id 28tuhrg8hv-3 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT) for ; Fri, 24 Feb 2017 13:31:52 -0800 Received: from facebook.com (2401:db00:21:603d:face:0:19:0) by mx-out.facebook.com (10.222.219.45) with ESMTP id a723b9c4fad811e687ba24be05904660-6d9fda00 for ; Fri, 24 Feb 2017 13:31:51 -0800 From: Shaohua Li Subject: [PATCH V5 1/6] mm: delete unnecessary TTU_* flags Date: Fri, 24 Feb 2017 13:31:44 -0800 Message-ID: <4be3ea1bc56b26fd98a54d0a6f70bec63f6d8980.1487965799.git.shli@fb.com> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: Kernel-team@fb.com, mhocko@suse.com, minchan@kernel.org, hughd@google.com, hannes@cmpxchg.org, riel@redhat.com, mgorman@techsingularity.net, akpm@linux-foundation.org Johannes pointed out TTU_LZFREE is unnecessary. It's true because we always have the flag set if we want to do an unmap. For cases we don't do an unmap, the TTU_LZFREE part of code should never run. Also the TTU_UNMAP is unnecessary. If no other flags set (for example, TTU_MIGRATION), an unmap is implied. The patch includes Johannes's cleanup and dead TTU_ACTION macro removal code Cc: Michal Hocko Cc: Hugh Dickins Cc: Rik van Riel Cc: Mel Gorman Cc: Andrew Morton Suggested-by: Johannes Weiner Acked-by: Johannes Weiner Acked-by: Minchan Kim Acked-by: Hillf Danton Signed-off-by: Shaohua Li --- include/linux/rmap.h | 22 +++++++++------------- mm/memory-failure.c | 2 +- mm/rmap.c | 2 +- mm/vmscan.c | 11 ++++------- 4 files changed, 15 insertions(+), 22 deletions(-) diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 8c89e90..7a39414 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -83,19 +83,17 @@ struct anon_vma_chain { }; enum ttu_flags { - TTU_UNMAP = 1, /* unmap mode */ - TTU_MIGRATION = 2, /* migration mode */ - TTU_MUNLOCK = 4, /* munlock mode */ - TTU_LZFREE = 8, /* lazy free mode */ - TTU_SPLIT_HUGE_PMD = 16, /* split huge PMD if any */ - - TTU_IGNORE_MLOCK = (1 << 8), /* ignore mlock */ - TTU_IGNORE_ACCESS = (1 << 9), /* don't age */ - TTU_IGNORE_HWPOISON = (1 << 10),/* corrupted page is recoverable */ - TTU_BATCH_FLUSH = (1 << 11), /* Batch TLB flushes where possible + TTU_MIGRATION = 0x1, /* migration mode */ + TTU_MUNLOCK = 0x2, /* munlock mode */ + + TTU_SPLIT_HUGE_PMD = 0x4, /* split huge PMD if any */ + TTU_IGNORE_MLOCK = 0x8, /* ignore mlock */ + TTU_IGNORE_ACCESS = 0x10, /* don't age */ + TTU_IGNORE_HWPOISON = 0x20, /* corrupted page is recoverable */ + TTU_BATCH_FLUSH = 0x40, /* Batch TLB flushes where possible * and caller guarantees they will * do a final flush if necessary */ - TTU_RMAP_LOCKED = (1 << 12) /* do not grab rmap lock: + TTU_RMAP_LOCKED = 0x80 /* do not grab rmap lock: * caller holds it */ }; @@ -193,8 +191,6 @@ static inline void page_dup_rmap(struct page *page, bool compound) int page_referenced(struct page *, int is_locked, struct mem_cgroup *memcg, unsigned long *vm_flags); -#define TTU_ACTION(x) ((x) & TTU_ACTION_MASK) - int try_to_unmap(struct page *, enum ttu_flags flags); /* Avoid racy checks */ diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 3d0f2fd..b78d080 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -906,7 +906,7 @@ EXPORT_SYMBOL_GPL(get_hwpoison_page); static int hwpoison_user_mappings(struct page *p, unsigned long pfn, int trapno, int flags, struct page **hpagep) { - enum ttu_flags ttu = TTU_UNMAP | TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS; + enum ttu_flags ttu = TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS; struct address_space *mapping; LIST_HEAD(tokill); int ret; diff --git a/mm/rmap.c b/mm/rmap.c index 8774791..96eb85c 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1418,7 +1418,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, */ VM_BUG_ON_PAGE(!PageSwapCache(page), page); - if (!PageDirty(page) && (flags & TTU_LZFREE)) { + if (!PageDirty(page)) { /* It's a freeable page by MADV_FREE */ dec_mm_counter(mm, MM_ANONPAGES); rp->lazyfreed++; diff --git a/mm/vmscan.c b/mm/vmscan.c index 26c3b40..68ea50d 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -971,7 +971,6 @@ static unsigned long shrink_page_list(struct list_head *page_list, int may_enter_fs; enum page_references references = PAGEREF_RECLAIM_CLEAN; bool dirty, writeback; - bool lazyfree = false; int ret = SWAP_SUCCESS; cond_resched(); @@ -1125,7 +1124,6 @@ static unsigned long shrink_page_list(struct list_head *page_list, goto keep_locked; if (!add_to_swap(page, page_list)) goto activate_locked; - lazyfree = true; may_enter_fs = 1; /* Adding to swap updated mapping */ @@ -1143,9 +1141,8 @@ static unsigned long shrink_page_list(struct list_head *page_list, * processes. Try to unmap it here. */ if (page_mapped(page) && mapping) { - switch (ret = try_to_unmap(page, lazyfree ? - (ttu_flags | TTU_BATCH_FLUSH | TTU_LZFREE) : - (ttu_flags | TTU_BATCH_FLUSH))) { + switch (ret = try_to_unmap(page, + ttu_flags | TTU_BATCH_FLUSH)) { case SWAP_FAIL: nr_unmap_fail++; goto activate_locked; @@ -1353,7 +1350,7 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone, } ret = shrink_page_list(&clean_pages, zone->zone_pgdat, &sc, - TTU_UNMAP|TTU_IGNORE_ACCESS, NULL, true); + TTU_IGNORE_ACCESS, NULL, true); list_splice(&clean_pages, page_list); mod_node_page_state(zone->zone_pgdat, NR_ISOLATED_FILE, -ret); return ret; @@ -1760,7 +1757,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, if (nr_taken == 0) return 0; - nr_reclaimed = shrink_page_list(&page_list, pgdat, sc, TTU_UNMAP, + nr_reclaimed = shrink_page_list(&page_list, pgdat, sc, 0, &stat, false); spin_lock_irq(&pgdat->lru_lock); -- 2.9.3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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