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From:   Alexandre Ghiti <alex@ghiti.fr>
To:     Andrew Morton <akpm@linux-foundation.org>,
        Vlastimil Babka <vbabka@suse.cz>,
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Cc:     Alexandre Ghiti <alex@ghiti.fr>
Subject: [PATCH v6 1/4] sh: Advertise gigantic page support
Date:   Thu,  7 Mar 2019 08:20:12 -0500
Message-Id: <20190307132015.26970-2-alex@ghiti.fr>
In-Reply-To: <20190307132015.26970-1-alex@ghiti.fr>
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sh actually supports gigantic pages and selecting
ARCH_HAS_GIGANTIC_PAGE allows it to allocate and free
gigantic pages at runtime.

At least sdk7786_defconfig exposes such a configuration with
huge pages of 64MB, pages of 4KB and MAX_ORDER = 11:
HPAGE_SHIFT (26) - PAGE_SHIFT (12) = 14 >= MAX_ORDER (11)

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
---
 arch/sh/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index a9c36f95744a..299a17bed67c 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -53,6 +53,7 @@ config SUPERH
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_NMI
 	select NEED_SG_DMA_LENGTH
+	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
 
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
-- 
2.20.1