1. 24 3月, 2011 1 次提交
  2. 21 3月, 2011 1 次提交
    • S
      introduce sys_syncfs to sync a single file system · b7ed78f5
      Sage Weil 提交于
      It is frequently useful to sync a single file system, instead of all
      mounted file systems via sync(2):
      
       - On machines with many mounts, it is not at all uncommon for some of
         them to hang (e.g. unresponsive NFS server).  sync(2) will get stuck on
         those and may never get to the one you do care about (e.g., /).
       - Some applications write lots of data to the file system and then
         want to make sure it is flushed to disk.  Calling fsync(2) on each
         file introduces unnecessary ordering constraints that result in a large
         amount of sub-optimal writeback/flush/commit behavior by the file
         system.
      
      There are currently two ways (that I know of) to sync a single super_block:
      
       - BLKFLSBUF ioctl on the block device: That also invalidates the bdev
         mapping, which isn't usually desirable, and doesn't work for non-block
         file systems.
       - 'mount -o remount,rw' will call sync_filesystem as an artifact of the
         current implemention.  Relying on this little-known side effect for
         something like data safety sounds foolish.
      
      Both of these approaches require root privileges, which some applications
      do not have (nor should they need?) given that sync(2) is an unprivileged
      operation.
      
      This patch introduces a new system call syncfs(2) that takes an fd and
      syncs only the file system it references.  Maybe someday we can
      
       $ sync /some/path
      
      and not get
      
       sync: ignoring all arguments
      
      The syscall is motivated by comments by Al and Christoph at the last LSF.
      syncfs(2) seems like an appropriate name given statfs(2).
      
      A similar ioctl was also proposed a while back, see
      	http://marc.info/?l=linux-fsdevel&m=127970513829285&w=2Signed-off-by: NSage Weil <sage@newdream.net>
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      b7ed78f5
  3. 15 3月, 2011 1 次提交
  4. 09 3月, 2011 1 次提交
    • J
      x86: Separate out entry text section · ea714547
      Jiri Olsa 提交于
      Put x86 entry code into a separate link section: .entry.text.
      
      Separating the entry text section seems to have performance
      benefits - caused by more efficient instruction cache usage.
      
      Running hackbench with perf stat --repeat showed that the change
      compresses the icache footprint. The icache load miss rate went
      down by about 15%:
      
       before patch:
               19417627  L1-icache-load-misses      ( +-   0.147% )
      
       after patch:
               16490788  L1-icache-load-misses      ( +-   0.180% )
      
      The motivation of the patch was to fix a particular kprobes
      bug that relates to the entry text section, the performance
      advantage was discovered accidentally.
      
      Whole perf output follows:
      
       - results for current tip tree:
      
        Performance counter stats for './hackbench/hackbench 10' (500 runs):
      
               19417627  L1-icache-load-misses      ( +-   0.147% )
             2676914223  instructions             #      0.497 IPC     ( +- 0.079% )
             5389516026  cycles                     ( +-   0.144% )
      
            0.206267711  seconds time elapsed   ( +-   0.138% )
      
       - results for current tip tree with the patch applied:
      
        Performance counter stats for './hackbench/hackbench 10' (500 runs):
      
               16490788  L1-icache-load-misses      ( +-   0.180% )
             2717734941  instructions             #      0.502 IPC     ( +- 0.079% )
             5414756975  cycles                     ( +-   0.148% )
      
            0.206747566  seconds time elapsed   ( +-   0.137% )
      Signed-off-by: NJiri Olsa <jolsa@redhat.com>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Nick Piggin <npiggin@kernel.dk>
      Cc: Eric Dumazet <eric.dumazet@gmail.com>
      Cc: masami.hiramatsu.pt@hitachi.com
      Cc: ananth@in.ibm.com
      Cc: davem@davemloft.net
      Cc: 2nddept-manager@sdl.hitachi.co.jp
      LKML-Reference: <20110307181039.GB15197@jolsa.redhat.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      ea714547
  5. 01 3月, 2011 1 次提交
  6. 02 2月, 2011 1 次提交
  7. 18 11月, 2010 1 次提交
  8. 15 10月, 2010 1 次提交
    • L
      Don't dump task struct in a.out core-dumps · 0eead9ab
      Linus Torvalds 提交于
      akiphie points out that a.out core-dumps have that odd task struct
      dumping that was never used and was never really a good idea (it goes
      back into the mists of history, probably the original core-dumping
      code).  Just remove it.
      
      Also do the access_ok() check on dump_write().  It probably doesn't
      matter (since normal filesystems all seem to do it anyway), but he
      points out that it's normally done by the VFS layer, so ...
      
      [ I suspect that we should possibly do "vfs_write()" instead of
        calling ->write directly.  That also does the whole fsnotify and write
        statistics thing, which may or may not be a good idea. ]
      
      And just to be anal, do this all for the x86-64 32-bit a.out emulation
      code too, even though it's not enabled (and won't currently even
      compile)
      Reported-by: Nakiphie <akiphie@lavabit.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0eead9ab
  9. 15 9月, 2010 2 次提交
  10. 14 8月, 2010 1 次提交
  11. 11 8月, 2010 1 次提交
  12. 28 7月, 2010 2 次提交
  13. 16 7月, 2010 1 次提交
  14. 21 4月, 2010 1 次提交
  15. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo 提交于
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
      
      percpu.h is included by sched.h and module.h and thus ends up being
      included when building most .c files.  percpu.h includes slab.h which
      in turn includes gfp.h making everything defined by the two files
      universally available and complicating inclusion dependencies.
      
      percpu.h -> slab.h dependency is about to be removed.  Prepare for
      this change by updating users of gfp and slab facilities include those
      headers directly instead of assuming availability.  As this conversion
      needs to touch large number of source files, the following script is
      used as the basis of conversion.
      
        http://userweb.kernel.org/~tj/misc/slabh-sweep.py
      
      The script does the followings.
      
      * Scan files for gfp and slab usages and update includes such that
        only the necessary includes are there.  ie. if only gfp is used,
        gfp.h, if slab is used, slab.h.
      
      * When the script inserts a new include, it looks at the include
        blocks and try to put the new include such that its order conforms
        to its surrounding.  It's put in the include block which contains
        core kernel includes, in the same order that the rest are ordered -
        alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
        doesn't seem to be any matching order.
      
      * If the script can't find a place to put a new include (mostly
        because the file doesn't have fitting include block), it prints out
        an error message indicating which .h file needs to be added to the
        file.
      
      The conversion was done in the following steps.
      
      1. The initial automatic conversion of all .c files updated slightly
         over 4000 files, deleting around 700 includes and adding ~480 gfp.h
         and ~3000 slab.h inclusions.  The script emitted errors for ~400
         files.
      
      2. Each error was manually checked.  Some didn't need the inclusion,
         some needed manual addition while adding it to implementation .h or
         embedding .c file was more appropriate for others.  This step added
         inclusions to around 150 files.
      
      3. The script was run again and the output was compared to the edits
         from #2 to make sure no file was left behind.
      
      4. Several build tests were done and a couple of problems were fixed.
         e.g. lib/decompress_*.c used malloc/free() wrappers around slab
         APIs requiring slab.h to be added manually.
      
      5. The script was run on all .h files but without automatically
         editing them as sprinkling gfp.h and slab.h inclusions around .h
         files could easily lead to inclusion dependency hell.  Most gfp.h
         inclusion directives were ignored as stuff from gfp.h was usually
         wildly available and often used in preprocessor macros.  Each
         slab.h inclusion directive was examined and added manually as
         necessary.
      
      6. percpu.h was updated not to include slab.h.
      
      7. Build test were done on the following configurations and failures
         were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
         distributed build env didn't work with gcov compiles) and a few
         more options had to be turned off depending on archs to make things
         build (like ipr on powerpc/64 which failed due to missing writeq).
      
         * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
         * powerpc and powerpc64 SMP allmodconfig
         * sparc and sparc64 SMP allmodconfig
         * ia64 SMP allmodconfig
         * s390 SMP allmodconfig
         * alpha SMP allmodconfig
         * um on x86_64 SMP allmodconfig
      
      8. percpu.h modifications were reverted so that it could be applied as
         a separate patch and serve as bisection point.
      
      Given the fact that I had only a couple of failures from tests on step
      6, I'm fairly confident about the coverage of this conversion patch.
      If there is a breakage, it's likely to be something in one of the arch
      headers which should be easily discoverable easily on most builds of
      the specific arch.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  16. 13 3月, 2010 3 次提交
  17. 11 2月, 2010 1 次提交
    • J
      x86, ia32_aout: do not kill argument mapping · 318f6b22
      Jiri Slaby 提交于
      Do not set current->mm->mmap to NULL in 32-bit emulation on 64-bit
      load_aout_binary after flush_old_exec as it would destroy already
      set brpm mapping with arguments.
      
      Introduced by b6a2fea3
      mm: variable length argument support
      where the argument mapping in bprm was added.
      
      [ hpa: this is a regression from 2.6.22... time to kill a.out? ]
      Signed-off-by: NJiri Slaby <jslaby@suse.cz>
      LKML-Reference: <1265831716-7668-1-git-send-email-jslaby@suse.cz>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ollie Wild <aaw@google.com>
      Cc: x86@kernel.org
      Cc: <stable@kernel.org>
      Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
      318f6b22
  18. 30 1月, 2010 2 次提交
    • H
      x86: get rid of the insane TIF_ABI_PENDING bit · 05d43ed8
      H. Peter Anvin 提交于
      Now that the previous commit made it possible to do the personality
      setting at the point of no return, we do just that for ELF binaries.
      And suddenly all the reasons for that insane TIF_ABI_PENDING bit go
      away, and we can just make SET_PERSONALITY() just do the obvious thing
      for a 32-bit compat process.
      
      Everything becomes much more straightforward this way.
      Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
      Cc: stable@kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      05d43ed8
    • L
      Split 'flush_old_exec' into two functions · 221af7f8
      Linus Torvalds 提交于
      'flush_old_exec()' is the point of no return when doing an execve(), and
      it is pretty badly misnamed.  It doesn't just flush the old executable
      environment, it also starts up the new one.
      
      Which is very inconvenient for things like setting up the new
      personality, because we want the new personality to affect the starting
      of the new environment, but at the same time we do _not_ want the new
      personality to take effect if flushing the old one fails.
      
      As a result, the x86-64 '32-bit' personality is actually done using this
      insane "I'm going to change the ABI, but I haven't done it yet" bit
      (TIF_ABI_PENDING), with SET_PERSONALITY() not actually setting the
      personality, but just the "pending" bit, so that "flush_thread()" can do
      the actual personality magic.
      
      This patch in no way changes any of that insanity, but it does split the
      'flush_old_exec()' function up into a preparatory part that can fail
      (still called flush_old_exec()), and a new part that will actually set
      up the new exec environment (setup_new_exec()).  All callers are changed
      to trivially comply with the new world order.
      Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
      Cc: stable@kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      221af7f8
  19. 28 1月, 2010 1 次提交
    • J
      x86: Use helpers for rlimits · 2854e72b
      Jiri Slaby 提交于
      Make sure compiler won't do weird things with limits.  Fetching them
      twice may return 2 different values after writable limits are
      implemented.
      
      We can either use rlimit helpers added in
      3e10e716 or ACCESS_ONCE if not
      applicable; this patch uses the helpers.
      Signed-off-by: NJiri Slaby <jslaby@suse.cz>
      LKML-Reference: <1264609942-24621-1-git-send-email-jslaby@suse.cz>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
      2854e72b
  20. 11 12月, 2009 1 次提交
  21. 06 11月, 2009 1 次提交
  22. 26 10月, 2009 1 次提交
  23. 13 10月, 2009 1 次提交
    • A
      net: Introduce recvmmsg socket syscall · a2e27255
      Arnaldo Carvalho de Melo 提交于
      Meaning receive multiple messages, reducing the number of syscalls and
      net stack entry/exit operations.
      
      Next patches will introduce mechanisms where protocols that want to
      optimize this operation will provide an unlocked_recvmsg operation.
      
      This takes into account comments made by:
      
      . Paul Moore: sock_recvmsg is called only for the first datagram,
        sock_recvmsg_nosec is used for the rest.
      
      . Caitlin Bestler: recvmmsg now has a struct timespec timeout, that
        works in the same fashion as the ppoll one.
      
        If the underlying protocol returns a datagram with MSG_OOB set, this
        will make recvmmsg return right away with as many datagrams (+ the OOB
        one) it has received so far.
      
      . Rémi Denis-Courmont & Steven Whitehouse: If we receive N < vlen
        datagrams and then recvmsg returns an error, recvmmsg will return
        the successfully received datagrams, store the error and return it
        in the next call.
      
      This paves the way for a subsequent optimization, sk_prot->unlocked_recvmsg,
      where we will be able to acquire the lock only at batch start and end, not at
      every underlying recvmsg call.
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a2e27255
  24. 01 10月, 2009 1 次提交
  25. 21 9月, 2009 1 次提交
    • I
      perf: Do the big rename: Performance Counters -> Performance Events · cdd6c482
      Ingo Molnar 提交于
      Bye-bye Performance Counters, welcome Performance Events!
      
      In the past few months the perfcounters subsystem has grown out its
      initial role of counting hardware events, and has become (and is
      becoming) a much broader generic event enumeration, reporting, logging,
      monitoring, analysis facility.
      
      Naming its core object 'perf_counter' and naming the subsystem
      'perfcounters' has become more and more of a misnomer. With pending
      code like hw-breakpoints support the 'counter' name is less and
      less appropriate.
      
      All in one, we've decided to rename the subsystem to 'performance
      events' and to propagate this rename through all fields, variables
      and API names. (in an ABI compatible fashion)
      
      The word 'event' is also a bit shorter than 'counter' - which makes
      it slightly more convenient to write/handle as well.
      
      Thanks goes to Stephane Eranian who first observed this misnomer and
      suggested a rename.
      
      User-space tooling and ABI compatibility is not affected - this patch
      should be function-invariant. (Also, defconfigs were not touched to
      keep the size down.)
      
      This patch has been generated via the following script:
      
        FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')
      
        sed -i \
          -e 's/PERF_EVENT_/PERF_RECORD_/g' \
          -e 's/PERF_COUNTER/PERF_EVENT/g' \
          -e 's/perf_counter/perf_event/g' \
          -e 's/nb_counters/nb_events/g' \
          -e 's/swcounter/swevent/g' \
          -e 's/tpcounter_event/tp_event/g' \
          $FILES
      
        for N in $(find . -name perf_counter.[ch]); do
          M=$(echo $N | sed 's/perf_counter/perf_event/g')
          mv $N $M
        done
      
        FILES=$(find . -name perf_event.*)
      
        sed -i \
          -e 's/COUNTER_MASK/REG_MASK/g' \
          -e 's/COUNTER/EVENT/g' \
          -e 's/\<event\>/event_id/g' \
          -e 's/counter/event/g' \
          -e 's/Counter/Event/g' \
          $FILES
      
      ... to keep it as correct as possible. This script can also be
      used by anyone who has pending perfcounters patches - it converts
      a Linux kernel tree over to the new naming. We tried to time this
      change to the point in time where the amount of pending patches
      is the smallest: the end of the merge window.
      
      Namespace clashes were fixed up in a preparatory patch - and some
      stylistic fallout will be fixed up in a subsequent patch.
      
      ( NOTE: 'counters' are still the proper terminology when we deal
        with hardware registers - and these sed scripts are a bit
        over-eager in renaming them. I've undone some of that, but
        in case there's something left where 'counter' would be
        better than 'event' we can undo that on an individual basis
        instead of touching an otherwise nicely automated patch. )
      Suggested-by: NStephane Eranian <eranian@google.com>
      Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Acked-by: NPaul Mackerras <paulus@samba.org>
      Reviewed-by: NArjan van de Ven <arjan@linux.intel.com>
      Cc: Mike Galbraith <efault@gmx.de>
      Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: David Howells <dhowells@redhat.com>
      Cc: Kyle McMartin <kyle@mcmartin.ca>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: <linux-arch@vger.kernel.org>
      LKML-Reference: <new-submission>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      cdd6c482
  26. 09 8月, 2009 1 次提交
  27. 01 5月, 2009 1 次提交
  28. 21 4月, 2009 1 次提交
  29. 03 4月, 2009 1 次提交
    • G
      preadv/pwritev: Add preadv and pwritev system calls. · f3554f4b
      Gerd Hoffmann 提交于
      This patch adds preadv and pwritev system calls.  These syscalls are a
      pretty straightforward combination of pread and readv (same for write).
      They are quite useful for doing vectored I/O in threaded applications.
      Using lseek+readv instead opens race windows you'll have to plug with
      locking.
      
      Other systems have such system calls too, for example NetBSD, check
      here: http://www.daemon-systems.org/man/preadv.2.html
      
      The application-visible interface provided by glibc should look like
      this to be compatible to the existing implementations in the *BSD family:
      
        ssize_t preadv(int d, const struct iovec *iov, int iovcnt, off_t offset);
        ssize_t pwritev(int d, const struct iovec *iov, int iovcnt, off_t offset);
      
      This prototype has one problem though: On 32bit archs is the (64bit)
      offset argument unaligned, which the syscall ABI of several archs doesn't
      allow to do.  At least s390 needs a wrapper in glibc to handle this.  As
      we'll need a wrappers in glibc anyway I've decided to push problem to
      glibc entriely and use a syscall prototype which works without
      arch-specific wrappers inside the kernel: The offset argument is
      explicitly splitted into two 32bit values.
      
      The patch sports the actual system call implementation and the windup in
      the x86 system call tables.  Other archs follow as separate patches.
      Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: <linux-api@vger.kernel.org>
      Cc: <linux-arch@vger.kernel.org>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      f3554f4b
  30. 28 3月, 2009 1 次提交
    • C
      generic compat_sys_ustat · 2b1c6bd7
      Christoph Hellwig 提交于
      Due to a different size of ino_t ustat needs a compat handler, but
      currently only x86 and mips provide one.  Add a generic compat_sys_ustat
      and switch all architectures over to it.  Instead of doing various
      user copy hacks compat_sys_ustat just reimplements sys_ustat as
      it's trivial.  This was suggested by Arnd Bergmann.
      
      Found by Eric Sandeen when running xfstests/017 on ppc64, which causes
      stack smashing warnings on RHEL/Fedora due to the too large amount of
      data writen by the syscall.
      Signed-off-by: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      2b1c6bd7
  31. 23 2月, 2009 3 次提交
  32. 07 2月, 2009 1 次提交
    • R
      x86-64: fix int $0x80 -ENOSYS return · c09249f8
      Roland McGrath 提交于
      One of my past fixes to this code introduced a different new bug.
      When using 32-bit "int $0x80" entry for a bogus syscall number,
      the return value is not correctly set to -ENOSYS.  This only happens
      when neither syscall-audit nor syscall tracing is enabled (i.e., never
      seen if auditd ever started).  Test program:
      
      	/* gcc -o int80-badsys -m32 -g int80-badsys.c
      	   Run on x86-64 kernel.
      	   Note to reproduce the bug you need auditd never to have started.  */
      
      	#include <errno.h>
      	#include <stdio.h>
      
      	int
      	main (void)
      	{
      	  long res;
      	  asm ("int $0x80" : "=a" (res) : "0" (99999));
      	  printf ("bad syscall returns %ld\n", res);
      	  return res != -ENOSYS;
      	}
      
      The fix makes the int $0x80 path match the sysenter and syscall paths.
      Reported-by: NDmitry V. Levin <ldv@altlinux.org>
      Signed-off-by: NRoland McGrath <roland@redhat.com>
      c09249f8
  33. 24 1月, 2009 1 次提交