On Mon, Oct 20, 2014 at 11:48:37PM +0200, Pieter Smith wrote: > Many embedded systems will not need this syscall, and omitting it > saves space. Add a new EXPERT config option CONFIG_SENDFILE_SYSCALL > (default y) to support compiling it out. Nice work, thanks! If there are no objections, and nobody has a tree they'd rather carry this through, I'll take the series through the tiny tree when it's ready to merge. > bloat-o-meter: > add/remove: 0/4 grow/shrink: 5/0 up/down: 23/-751 (-728) > function old new delta > sys_pwritev 115 122 +7 > sys_preadv 115 122 +7 > fdput_pos 29 36 +7 > sys_pwrite64 115 116 +1 > sys_pread64 115 116 +1 > fdput 11 - -11 > sys_sendfile 122 - -122 > sys_sendfile64 126 - -126 > do_sendfile 492 - -492 Interesting inlining decisions by GCC here. Got a bloat-o-meter for the two-patch series, by any chance? (Also, is this with tinyconfig? In particular, with OPTIMIZE_INLINING and OPTIMIZE_FOR_SIZE?) I'm wondering if moving sendfile to a separate file made GCC put fdput out-of-line, and compiling it out reversed that again. > Signed-off-by: Pieter Smith <pieter@xxxxxxxxxx> Reviewed-by: Josh Triplett <josh@xxxxxxxxxxxxxxxx> > --- > fs/Makefile | 3 ++- > init/Kconfig | 10 ++++++++++ > kernel/sys_ni.c | 4 ++++ > 3 files changed, 16 insertions(+), 1 deletion(-) > > diff --git a/fs/Makefile b/fs/Makefile > index 1e3423f..1bbfea7 100644 > --- a/fs/Makefile > +++ b/fs/Makefile > @@ -5,7 +5,7 @@ > # Rewritten to use lists instead of if-statements. > # > > -obj-y := open.o read_write.o sendfile.o file_table.o super.o \ > +obj-y := open.o read_write.o file_table.o super.o \ > char_dev.o stat.o exec.o pipe.o namei.o fcntl.o \ > ioctl.o readdir.o select.o dcache.o inode.o \ > attr.o bad_inode.o file.o filesystems.o namespace.o \ > @@ -38,6 +38,7 @@ obj-$(CONFIG_COMPAT_BINFMT_ELF) += compat_binfmt_elf.o > obj-$(CONFIG_BINFMT_ELF_FDPIC) += binfmt_elf_fdpic.o > obj-$(CONFIG_BINFMT_SOM) += binfmt_som.o > obj-$(CONFIG_BINFMT_FLAT) += binfmt_flat.o > +obj-$(CONFIG_SENDFILE_SYSCALL) += sendfile.o > > obj-$(CONFIG_FS_MBCACHE) += mbcache.o > obj-$(CONFIG_FS_POSIX_ACL) += posix_acl.o > diff --git a/init/Kconfig b/init/Kconfig > index 782a65b..df6785c 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -1547,6 +1547,16 @@ config ADVISE_SYSCALLS > applications use these syscalls, you can disable this option to save > space. > > +config SENDFILE_SYSCALL > + bool "Enable sendfile syscall" if EXPERT > + default y > + help > + This option enables the sendfile syscall, used by applications to copy > + data between file descriptors. Because sendfile performs the copying > + within the kernel, it is more efficient than the combination of read > + and write. If building an embedded system where no applications use > + the sendfile syscall, you can disable this option to save space. > + I'm thinking of adding a submenu to group config FOO_SYSCALL options. :) I'll probably push that as part of the 3.19 merge window, as a patch on top of all of the individual tinification options. > config PCI_QUIRKS > default y > bool "Enable PCI quirk workarounds" if EXPERT > diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c > index d4709d4..b068de7 100644 > --- a/kernel/sys_ni.c > +++ b/kernel/sys_ni.c > @@ -159,6 +159,10 @@ cond_syscall(sys_uselib); > cond_syscall(sys_fadvise64); > cond_syscall(sys_fadvise64_64); > cond_syscall(sys_madvise); > +cond_syscall(sys_sendfile); > +cond_syscall(sys_sendfile64); > +cond_syscall(compat_sys_sendfile); > +cond_syscall(compat_sys_sendfile64); > > /* arch-specific weak syscall entries */ > cond_syscall(sys_pciconfig_read); > -- > 1.9.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
