From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Carstens Subject: Re: [PATCH V3 2/5] mm: mlock: Add new mlock, munlock, and munlockall system calls Date: Wed, 8 Jul 2015 08:46:07 +0200 Message-ID: <20150708064607.GB7079@osiris> References: <1436288623-13007-1-git-send-email-emunson@akamai.com> <1436288623-13007-3-git-send-email-emunson@akamai.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1436288623-13007-3-git-send-email-emunson@akamai.com> Sender: linux-m68k-owner@vger.kernel.org To: Eric B Munson Cc: Andrew Morton , Michal Hocko , Vlastimil Babka , linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, adi-buildroot-devel@lists.sourceforge.net, linux-cris-kernel@axis.com, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@linux-mips.org, linux-am33-list@redhat.com, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-xtensa@linux-xtensa.org, linux-api@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org List-Id: linux-api@vger.kernel.org On Tue, Jul 07, 2015 at 01:03:40PM -0400, Eric B Munson wrote: > With the refactored mlock code, introduce new system calls for mlock, > munlock, and munlockall. The new calls will allow the user to specify > what lock states are being added or cleared. mlock2 and munlock2 are > trivial at the moment, but a follow on patch will add a new mlock state > making them useful. > > munlock2 addresses a limitation of the current implementation. If a > user calls mlockall(MCL_CURRENT | MCL_FUTURE) and then later decides > that MCL_FUTURE should be removed, they would have to call munlockall() > followed by mlockall(MCL_CURRENT) which could potentially be very > expensive. The new munlockall2 system call allows a user to simply > clear the MCL_FUTURE flag. > > Signed-off-by: Eric B Munson ... > diff --git a/arch/s390/kernel/syscalls.S b/arch/s390/kernel/syscalls.S > index 1acad02..f6d81d6 100644 > --- a/arch/s390/kernel/syscalls.S > +++ b/arch/s390/kernel/syscalls.S > @@ -363,3 +363,6 @@ SYSCALL(sys_bpf,compat_sys_bpf) > SYSCALL(sys_s390_pci_mmio_write,compat_sys_s390_pci_mmio_write) > SYSCALL(sys_s390_pci_mmio_read,compat_sys_s390_pci_mmio_read) > SYSCALL(sys_execveat,compat_sys_execveat) > +SYSCALL(sys_mlock2,compat_sys_mlock2) /* 355 */ > +SYSCALL(sys_munlock2,compat_sys_munlock2) > +SYSCALL(sys_munlockall2,compat_sys_munlockall2) FWIW, you would also need to add matching lines to the two files arch/s390/include/uapi/asm/unistd.h arch/s390/kernel/compat_wrapper.c so that the system call would be wired up on s390.