From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id E66536B050B for ; Tue, 1 Aug 2017 05:01:04 -0400 (EDT) Received: by mail-wm0-f69.google.com with SMTP id p17so1663511wmd.5 for ; Tue, 01 Aug 2017 02:01:04 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id k184si824537wmk.115.2017.08.01.02.01.03 for (version=TLS1 cipher=AES128-SHA bits=128/128); Tue, 01 Aug 2017 02:01:03 -0700 (PDT) Date: Tue, 1 Aug 2017 11:01:01 +0200 From: Michal Hocko Subject: Re: [PATCH 3/3] mm:shm: Use new hugetlb size encoding definitions Message-ID: <20170801090100.GE15774@dhcp22.suse.cz> References: <1501527386-10736-1-git-send-email-mike.kravetz@oracle.com> <1501527386-10736-4-git-send-email-mike.kravetz@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1501527386-10736-4-git-send-email-mike.kravetz@oracle.com> Sender: owner-linux-mm@kvack.org List-ID: To: Mike Kravetz Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Matthew Wilcox , akpm@linux-foundation.org, ak@linux.intel.com, mtk.manpages@gmail.com, Davidlohr Bueso , khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, aarcange@redhat.com, Arnd Bergmann On Mon 31-07-17 11:56:26, Mike Kravetz wrote: > Use the common definitions from hugetlb_encode.h header file for > encoding hugetlb size definitions in shmget system call flags. > > In addition, move these definitions from the internal (kernel) to > user (uapi) header file. > > Suggested-by: Matthew Wilcox > Signed-off-by: Mike Kravetz Acked-by: Michal Hocko > --- > include/linux/shm.h | 17 ----------------- > include/uapi/linux/shm.h | 31 +++++++++++++++++++++++++++++-- > 2 files changed, 29 insertions(+), 19 deletions(-) > > diff --git a/include/linux/shm.h b/include/linux/shm.h > index 04e8818..d56285a 100644 > --- a/include/linux/shm.h > +++ b/include/linux/shm.h > @@ -27,23 +27,6 @@ struct shmid_kernel /* private to the kernel */ > /* shm_mode upper byte flags */ > #define SHM_DEST 01000 /* segment will be destroyed on last detach */ > #define SHM_LOCKED 02000 /* segment will not be swapped */ > -#define SHM_HUGETLB 04000 /* segment will use huge TLB pages */ > -#define SHM_NORESERVE 010000 /* don't check for reservations */ > - > -/* Bits [26:31] are reserved */ > - > -/* > - * When SHM_HUGETLB is set bits [26:31] encode the log2 of the huge page size. > - * This gives us 6 bits, which is enough until someone invents 128 bit address > - * spaces. > - * > - * Assume these are all power of twos. > - * When 0 use the default page size. > - */ > -#define SHM_HUGE_SHIFT 26 > -#define SHM_HUGE_MASK 0x3f > -#define SHM_HUGE_2MB (21 << SHM_HUGE_SHIFT) > -#define SHM_HUGE_1GB (30 << SHM_HUGE_SHIFT) > > #ifdef CONFIG_SYSVIPC > struct sysv_shm { > diff --git a/include/uapi/linux/shm.h b/include/uapi/linux/shm.h > index 1fbf24e..cf23c87 100644 > --- a/include/uapi/linux/shm.h > +++ b/include/uapi/linux/shm.h > @@ -3,6 +3,7 @@ > > #include > #include > +#include > #ifndef __KERNEL__ > #include > #endif > @@ -40,11 +41,37 @@ struct shmid_ds { > /* Include the definition of shmid64_ds and shminfo64 */ > #include > > -/* permission flag for shmget */ > +/* > + * shmget() shmflg values. > + */ > +/* The bottom nine bits are the same as open(2) mode flags */ > #define SHM_R 0400 /* or S_IRUGO from */ > #define SHM_W 0200 /* or S_IWUGO from */ > +/* Bits 9 & 10 are IPC_CREAT and IPC_EXCL */ > +#define SHM_HUGETLB 04000 /* segment will use huge TLB pages */ > +#define SHM_NORESERVE 010000 /* don't check for reservations */ > + > +/* > + * Huge page size encoding when SHM_HUGETLB is specified, and a huge page > + * size other than the default is desired. See hugetlb_encode.h > + */ > +#define SHM_HUGE_SHIFT HUGETLB_FLAG_ENCODE_SHIFT > +#define SHM_HUGE_MASK HUGETLB_FLAG_ENCODE_MASK > + > +#define SHM_HUGE_64KB HUGETLB_FLAG_ENCODE_64KB > +#define SHM_HUGE_512KB HUGETLB_FLAG_ENCODE_512KB > +#define SHM_HUGE_1MB HUGETLB_FLAG_ENCODE_1MB > +#define SHM_HUGE_2MB HUGETLB_FLAG_ENCODE_2MB > +#define SHM_HUGE_8MB HUGETLB_FLAG_ENCODE_8MB > +#define SHM_HUGE_16MB HUGETLB_FLAG_ENCODE_16MB > +#define SHM_HUGE_256MB HUGETLB_FLAG_ENCODE_256MB > +#define SHM_HUGE_1GB HUGETLB_FLAG_ENCODE_1GB > +#define SHM_HUGE_2GB HUGETLB_FLAG_ENCODE_2GB > +#define SHM_HUGE_16GB HUGETLB_FLAG_ENCODE_16GB > > -/* mode for attach */ > +/* > + * shmat() shmflg values > + */ > #define SHM_RDONLY 010000 /* read-only access */ > #define SHM_RND 020000 /* round attach address to SHMLBA boundary */ > #define SHM_REMAP 040000 /* take-over region on attach */ > -- > 2.7.5 -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org