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From:   Vlastimil Babka <vbabka@suse.cz>
To:     linux-mm@kvack.org, Christoph Lameter <cl@linux.com>,
        David Rientjes <rientjes@google.com>,
        Pekka Enberg <penberg@kernel.org>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, Mike Galbraith <efault@gmx.de>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Thomas Gleixner <tglx@linutronix.de>,
        Mel Gorman <mgorman@techsingularity.net>,
        Vlastimil Babka <vbabka@suse.cz>
Subject: [PATCH v6 01/33] mm, slub: don't call flush_all() from slab_debug_trace_open()
Date:   Sat,  4 Sep 2021 12:49:31 +0200
Message-Id: <20210904105003.11688-2-vbabka@suse.cz>
In-Reply-To: <20210904105003.11688-1-vbabka@suse.cz>
References: <20210904105003.11688-1-vbabka@suse.cz>
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slab_debug_trace_open() can only be called on caches with SLAB_STORE_USER flag
and as with all slub debugging flags, such caches avoid cpu or percpu partial
slabs altogether, so there's nothing to flush.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Christoph Lameter <cl@linux.com>
---
 mm/slub.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index f77d8cd79ef7..f6063ec97a55 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -5825,9 +5825,6 @@ static int slab_debug_trace_open(struct inode *inode, struct file *filep)
 	if (!alloc_loc_track(t, PAGE_SIZE / sizeof(struct location), GFP_KERNEL))
 		return -ENOMEM;
 
-	/* Push back cpu slabs */
-	flush_all(s);
-
 	for_each_kmem_cache_node(s, node, n) {
 		unsigned long flags;
 		struct page *page;
-- 
2.33.0