Commit Graph
77 Commits
Author SHA1 Message Date
Denys Vlasenko 2aa362c49c coredump: extend core dump note section to contain file names of mapped files
This note has the following format:

long count     -- how many files are mapped
long page_size -- units for file_ofs
array of [COUNT] elements of
   long start
   long end
   long file_ofs
followed by COUNT filenames in ASCII: "FILE1" NUL "FILE2" NUL...

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Amerigo Wang <amwang@redhat.com>
Cc: "Jonathan M. Foote" <jmfoote@cert.org>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:05:17 +09:00
Denys Vlasenko 49ae4d4b11 coredump: add a new elf note with siginfo of the signal
Existing PRSTATUS note contains only si_signo, si_code, si_errno fields
from the siginfo of the signal which caused core to be dumped.

There are tools which try to analyze crashes for possible security
implications, and they want to use, among other data, si_addr field from
the SIGSEGV.

This patch adds a new elf note, NT_SIGINFO, which contains the complete
siginfo_t of the signal which killed the process.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Amerigo Wang <amwang@redhat.com>
Cc: "Jonathan M. Foote" <jmfoote@cert.org>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:05:16 +09:00
Denys Vlasenko 751f409db6 compat: move compat_siginfo_t definition to asm/compat.h
This is a preparatory patch for the introduction of NT_SIGINFO elf note.

Make the location of compat_siginfo_t uniform across eight architectures
which have it.  Now it can be pulled in by including asm/compat.h or
linux/compat.h.

Most of the copies are verbatim.  compat_uid[32]_t had to be replaced by
__compat_uid[32]_t.  compat_uptr_t had to be moved up before
compat_siginfo_t in asm/compat.h on a several architectures (tile already
had it moved up).  compat_sigval_t had to be relocated from linux/compat.h
to asm/compat.h.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Amerigo Wang <amwang@redhat.com>
Cc: "Jonathan M. Foote" <jmfoote@cert.org>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:05:16 +09:00
Denys Vlasenko 5ab1c309b3 coredump: pass siginfo_t* to do_coredump() and below, not merely signr
This is a preparatory patch for the introduction of NT_SIGINFO elf note.

With this patch we pass "siginfo_t *siginfo" instead of "int signr" to
do_coredump() and put it into coredump_params.  It will be used by the
next patch.  Most changes are simple s/signr/siginfo->si_signo/.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Amerigo Wang <amwang@redhat.com>
Cc: "Jonathan M. Foote" <jmfoote@cert.org>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:05:16 +09:00
Denys Vlasenko f34f9d186d coredump: prevent double-free on an error path in core dumper
In !CORE_DUMP_USE_REGSET case, if elf_note_info_init fails to allocate
memory for info->fields, it frees already allocated stuff and returns
error to its caller, fill_note_info.  Which in turn returns error to its
caller, elf_core_dump.  Which jumps to cleanup label and calls
free_note_info, which will happily try to free all info->fields again.
BOOM.

This is the fix.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Venu Byravarasu <vbyravarasu@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2012-09-26 22:20:21 -04:00
Denys Vlasenko 133fd9f5cd vsprintf: further optimize decimal conversion
Previous code was using optimizations which were developed to work well
even on narrow-word CPUs (by today's standards).  But Linux runs only on
32-bit and wider CPUs.  We can use that.

First: using 32x32->64 multiply and trivial 32-bit shift, we can correctly
divide by 10 much larger numbers, and thus we can print groups of 9 digits
instead of groups of 5 digits.

Next: there are two algorithms to print larger numbers.  One is generic:
divide by 1000000000 and repeatedly print groups of (up to) 9 digits.
It's conceptually simple, but requires an (unsigned long long) /
1000000000 division.

Second algorithm splits 64-bit unsigned long long into 16-bit chunks,
manipulates them cleverly and generates groups of 4 decimal digits.  It so
happens that it does NOT require long long division.

If long is > 32 bits, division of 64-bit values is relatively easy, and we
will use the first algorithm.  If long long is > 64 bits (strange
architecture with VERY large long long), second algorithm can't be used,
and we again use the first one.

Else (if long is 32 bits and long long is 64 bits) we use second one.

And third: there is a simple optimization which takes fast path not only
for zero as was done before, but for all one-digit numbers.

In all tested cases new code is faster than old one, in many cases by 30%,
in few cases by more than 50% (for example, on x86-32, conversion of
12345678).  Code growth is ~0 in 32-bit case and ~130 bytes in 64-bit
case.

This patch is based upon an original from Michal Nazarewicz.

[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Douglas W Jones <jones@cs.uiowa.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31 17:49:27 -07:00
Denys Vlasenko ee00560c7d ptrace: remove PTRACE_SEIZE_DEVEL bit
PTRACE_SEIZE code is tested and ready for production use, remove the
code which requires special bit in data argument to make PTRACE_SEIZE
work.

Strace team prepares for a new release of strace, and we would like to
ship the code which uses PTRACE_SEIZE, preferably after this change goes
into released kernel.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:41 -07:00
Denys Vlasenko 5cdf389aee ptrace: renumber PTRACE_EVENT_STOP so that future new options and events can match
PTRACE_EVENT_foo and PTRACE_O_TRACEfoo used to match.

New PTRACE_EVENT_STOP is the first event which has no corresponding
PTRACE_O_TRACE option.  If we will ever want to add another such option,
its PTRACE_EVENT's value will collide with PTRACE_EVENT_STOP's value.

This patch changes PTRACE_EVENT_STOP value to prevent this.

While at it, added a comment - the one atop PTRACE_EVENT block, saying
"Wait extended result codes for the above trace options", is not true
for PTRACE_EVENT_STOP.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Tejun Heo <tj@kernel.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:41 -07:00
Denys Vlasenko aa9147c98f ptrace: make PTRACE_SEIZE set ptrace options specified in 'data' parameter
This can be used to close a few corner cases in strace where we get
unwanted racy behavior after attach, but before we have a chance to set
options (the notorious post-execve SIGTRAP comes to mind), and removes
the need to track "did we set opts for this task" state in strace
internals.

While we are at it:

Make it possible to extend SEIZE in the future with more functionality
by passing non-zero 'addr' parameter.  To that end, error out if 'addr'
is non-zero.  PTRACE_ATTACH did not (and still does not) have such
check, and users (strace) do pass garbage there...  let's avoid
repeating this mistake with SEIZE.

Set all task->ptrace bits in one operation - before this change, we were
adding PT_SEIZED and PT_PTRACE_CAP with task->ptrace |= BIT ops.  This
was probably ok (not a bug), but let's be on a safer side.

Changes since v2: use (unsigned long) casts instead of (long) ones, move
PTRACE_SEIZE_DEVEL-related code to separate lines of code.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Pedro Alves <palves@redhat.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:40 -07:00
Denys Vlasenko 86b6c1f301 ptrace: simplify PTRACE_foo constants and PTRACE_SETOPTIONS code
Exchange PT_TRACESYSGOOD and PT_PTRACE_CAP bit positions, which makes
PT_option bits contiguous and therefore makes code in
ptrace_setoptions() much simpler.

Every PTRACE_O_TRACEevent is defined to (1 << PTRACE_EVENT_event)
instead of using explicit numeric constants, to ensure we don't mess up
relationship between bit positions and event ids.

PT_EVENT_FLAG_SHIFT was not particularly useful, PT_OPT_FLAG_SHIFT with
value of PT_EVENT_FLAG_SHIFT-1 is easier to use.

PT_TRACE_MASK constant is nuked, the only its use is replaced by
(PTRACE_O_MASK << PT_OPT_FLAG_SHIFT).

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:40 -07:00
Denys Vlasenko 8c5cf9e5c5 ptrace: don't modify flags on PTRACE_SETOPTIONS failure
On ptrace(PTRACE_SETOPTIONS, pid, 0, <opts>), we used to set those
option bits which are known, and then fail with -EINVAL if there are
some unknown bits in <opts>.

This is inconsistent with typical error handling, which does not change
any state if input is invalid.

This patch changes PTRACE_SETOPTIONS behavior so that in this case, we
return -EINVAL and don't change any bits in task->ptrace.

It's very unlikely that there is userspace code in the wild which will
be affected by this change: it should have the form

    ptrace(PTRACE_SETOPTIONS, pid, 0, PTRACE_O_BOGUSOPT)

where PTRACE_O_BOGUSOPT is a constant unknown to the kernel.  But kernel
headers, naturally, don't contain any PTRACE_O_BOGUSOPTs, thus the only
way userspace can use one if it defines one itself.  I can't see why
anyone would do such a thing deliberately.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:40 -07:00
Denys Vlasenko 397a21f24d kernel/exit.c: if init dies, log a signal which killed it, if any
I just received another user's pleas for help when their init
mysteriously died.  I again explained that they need to check whether it
died because of bad instruction, a segv, or something else.  Which was
an annoying detour into writing a trivial C program to spawn his init
and print its exit code:

  http://lists.busybox.net/pipermail/busybox/2012-January/077172.html

I hear you saying "just test it under /bin/sh".  Well, the crashing init
_was_ /bin/sh.

Which prompted me to make kernel do this first step automatically.  We can
print exit code, which makes it possible to see that death was from e.g.
SIGILL without writing test programs.

[akpm@linux-foundation.org: add 0x to hex number output]
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23 16:58:32 -07:00
Denys Vlasenko a46621a3a8 net: Deinline __nlmsg_put and genlmsg_put. -7k code on i386 defconfig.
text	   data	    bss	    dec	    hex	filename
8455963	 532732	1810804	10799499 a4c98b	vmlinux.o.before
8448899	 532732	1810804	10792435 a4adf3	vmlinux.o

This change also removes commented-out copy of __nlmsg_put
which was last touched in 2005 with "Enable once all users
have been converted" comment on top.

Changes in v2: rediffed against net-next.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-30 15:22:06 -05:00
Denys Vlasenko bb188d7e64 ptrace: make former thread ID available via PTRACE_GETEVENTMSG after PTRACE_EVENT_EXEC stop
When multithreaded program execs under ptrace,
all traced threads report WIFEXITED status, except for
thread group leader and the thread which execs.

Unless tracer tracks thread group relationship between tracees,
which is a nontrivial task, it will not detect that
execed thread no longer exists.

This patch allows tracer to figure out which thread
performed this exec, by requesting PTRACE_GETEVENTMSG
in PTRACE_EVENT_EXEC stop.

Another, samller problem which is solved by this patch
is that tracer now can figure out which of the several
concurrent execs in multithreaded program succeeded.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2011-07-01 18:51:49 +02:00
Denys Vlasenko a67ef278e2 drivers/video/fbmem.c: simplify strlen()==0 check in fb_get_options()
Replaced !strlen(str) check with !str[0].  Removed the variable which was
used solely to store strlen result.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11 08:59:09 -07:00
Denys Vlasenko 26c5be3c75 fbcon: uninline four foo_update_attr() functions
This patch uninlines four similar functions, foo_update_attr(), in four
fbcon-related files.

These functions contain loops, two of theam have _nested_ loops, and they
have more than one callsite each.  I think they should not be inlined.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11 08:59:09 -07:00
Denys Vlasenko da909ce4c0 fbcon: uninline large static function get_color()
This function's body is good two screenfuls and it has six callsites.  No
apparent reason why it is marked inline.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11 08:59:09 -07:00
Denys Vlasenko 1ce53adf13 modpost: support objects with more than 64k sections
This patch makes modpost able to process object files with more than
64k sections. Needed for huge kernel builds (allyesconfig, for example)
with -ffunction-sections. 64k sections handling is covered, for example,
by this document:

"IA-64 gABI Proposal 74: Section Indexes"
http://www.codesourcery.com/public/cxx-abi/abi/prop-74-sindex.html

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-08-03 15:05:56 +02:00
Denys Vlasenko e9cfaa9f4c Rename .text.start to .text..start.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:01 +01:00
Denys Vlasenko b6f4e451de Rename special text sections in arch/frv from .text.XXX to .text..XXX.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:01 +01:00
Denys Vlasenko a7df554ea0 Rename .data.lock_aligned to .data..lock_aligned.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:01 +01:00
Denys Vlasenko 2c31c341a8 Rename .data.initvect to .data..initvect.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:01 +01:00
Denys Vlasenko c273fb3b5d Rename .data.init to .data..init.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:01 +01:00
Denys Vlasenko 07b3bb1ef2 Rename .data.nosave to .data..nosave.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:01 +01:00
Denys Vlasenko 9bf5942486 Rename .text.startup to .text..startup.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:01 +01:00
Denys Vlasenko 819d67621e Rename .text.page_aligned to .text..page_aligned.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:00 +01:00
Denys Vlasenko 75ddb0e87d Rename .text.lock to .text..lock.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:00 +01:00
Denys Vlasenko 2b55f3672c Rename .text.ivt to .text..ivt.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:00 +01:00
Denys Vlasenko 041d5f94c4 Rename .rodata.compressed to .rodata..compressed.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:00 +01:00
Denys Vlasenko d56a3c1a9f Rename .data.vmpages and .data.vm0.XXX to .data..vmpages and .data..vm0.XXX.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:00 +01:00
Denys Vlasenko 54cb27a71f Rename .data.read_mostly to .data..read_mostly.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:00 +01:00
Denys Vlasenko 3d9a854c2d Rename .data[.percpu][.XXX] to .data[..percpu][..XXX].
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:26:00 +01:00
Denys Vlasenko dafb932067 Rename .data..patch.XXX to .data..patch.XXX.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:25:59 +01:00
Denys Vlasenko 9d1578a3ba Rename .data.init_irqstack to .data..init_irqstack.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:25:59 +01:00
Denys Vlasenko e1cb14b85f Rename .data.gate to .data..gate.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:25:59 +01:00
Denys Vlasenko 1360e07070 Rename .bss.stack to .bss..stack.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-03-03 11:25:59 +01:00
Denys Vlasenko 1c12718504 parisc: fix find_extend_vma() breakage
The STACK_GROWSUP case of stack expansion was missing a test for 'prev',
which got removed by commit cb8f488c33
("mmap.c: deinline a few functions") by mistake.

I found my original email in "sent" folder. The patch in that mail
does NOT remove !prev. That change had beed added by someone else.

Ok, I think we are not much interested in who did it, let's
fix it for good.

[ "It looks like this was caused by me fixing rejects.  That was the
  fancy include-lots-of-context-so-it-wont-apply patch." - akpm ]

Reported-and-bisected-by: Helge Deller <deller@gmx.de>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-12 10:37:48 -08:00
Denys Vlasenko 060ae855a8 [SCSI] aic7xxx: update *_shipped files
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-23 11:42:12 -05:00
Denys Vlasenko 7b61ab89f9 [SCSI] aic7xxx: update .reg files
Update .reg files, marking unused registers with dont_generate_debug_code.
Comment explains how to use it.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-23 11:42:12 -05:00
Denys Vlasenko fa25b99a50 [SCSI] aic7xxx: introduce "dont_generate_debug_code" keyword in aicasm parser
aic7xxx still contains ~30kb of dead code if pretty printing of registers
is requested. These patches deal with it.

Size differences:

   text    data     bss     dec     hex filename
DEBUG_ENABLE+PRETTY_PRINT:
 234697    2362    1188  238247   3a2a7 linux-2.6.26-rc8-/drivers/scsi/aic7xxx/built-in.o
 205092    2362    1188  208642   32f02 linux-2.6.26-rc8/drivers/scsi/aic7xxx/built-in.o
NO_DEBUG_ENABLE+PRETTY_PRINT:
 227272    2362    1172  230806   38596 linux-2.6.26-rc8-/drivers/scsi/aic7xxx/built-in.o
 197671    2362    1172  201205   311f5 linux-2.6.26-rc8/drivers/scsi/aic7xxx/built-in.o
DEBUG_ENABLE+NO_PRETTY_PRINT:
 192457    2362    1188  196007   2fda7 linux-2.6.26-rc8-/drivers/scsi/aic7xxx/built-in.o
 192457    2362    1188  196007   2fda7 linux-2.6.26-rc8/drivers/scsi/aic7xxx/built-in.o
NO_DEBUG_ENABLE+NO_PRETTY_PRINT:
 185040    2362    1172  188574   2e09e linux-2.6.26-rc8-/drivers/scsi/aic7xxx/built-in.o
 185040    2362    1172  188574   2e09e linux-2.6.26-rc8/drivers/scsi/aic7xxx/built-in.o

This patch:

Introduce "dont_generate_debug_code" keyword in aicasm parser.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-23 11:42:12 -05:00
Denys Vlasenko cb8f488c33 mmap.c: deinline a few functions
__vma_link_file and expand_downwards functions are not small, yeat they
are marked inline.  They probably had one callsite sometime in the past,
but now they have more.  In order to prevent similar thing, I also
deinlined expand_upwards, despite it having only pne callsite.  Nowadays
gcc auto-inlines such static functions anyway.  In find_extend_vma, I
removed one extra level of indirection.

Patch is deliberately generated with -U $BIGNUM to make
it easier to see that functions are big.

Result:

# size */*/mmap.o */vmlinux
   text    data     bss     dec     hex filename
   9514     188      16    9718    25f6 0.org/mm/mmap.o
   9237     188      16    9441    24e1 deinline/mm/mmap.o
6124402  858996  389480 7372878  70804e 0.org/vmlinux
6124113  858996  389480 7372589  707f2d deinline/vmlinux

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:32 -07:00
Denys Vlasenko b41759cf11 [XFS] Remove unused wbc parameter from xfs_start_page_writeback()
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31057a

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-07-28 16:58:09 +10:00
Denys Vlasenko 4f0e8a9816 [XFS] Remove unused Falgs parameter from xfs_qm_dqpurge()
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31056a

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-07-28 16:58:08 +10:00
Denys Vlasenko f0e2d93c29 [XFS] Remove unused arg from kmem_free()
kmem_free() function takes (ptr, size) arguments but doesn't actually use
second one.

This patch removes size argument from all callsites.

SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31050a

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-07-28 16:58:07 +10:00
Denys Vlasenko d2d9648ec6 [PATCH] reuse xxx_fifo_fops for xxx_pipe_fops
Merge fifo and pipe file_operations.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:06 -04:00
Denys Vlasenko 2f0f2a334b module: turn longs into ints for module sizes
This shrinks module.o and each *.ko file.

And finally, structure members which hold length of module
code (four such members there) and count of symbols
are converted from longs to ints.

We cannot possibly have a module where 32 bits won't
be enough to hold such counts.

For one, module loading checks module size for sanity
before loading, so such insanely big module will fail
that test first.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:27 +10:00
Denys Vlasenko f7f5b67557 Shrink struct module: CONFIG_UNUSED_SYMBOLS ifdefs
module.c and module.h conatains code for finding
exported symbols which are declared with EXPORT_UNUSED_SYMBOL,
and this code is compiled in even if CONFIG_UNUSED_SYMBOLS is not set
and thus there can be no EXPORT_UNUSED_SYMBOLs in modules anyway
(because EXPORT_UNUSED_SYMBOL(x) are compiled out to nothing then).

This patch adds required #ifdefs.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-22 19:24:27 +10:00
Denys Vlasenko 980b306a29 [SCSI] aic7xxx: add const
This patch adds more const keywords where appropriate.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-27 12:20:00 -05:00
Denys Vlasenko d1d7b19d43 [SCSI] aic7xxx: add static
This patch adds static (and sometimes const) keywords where appropriate.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-27 12:20:00 -05:00
Denys Vlasenko be0d67680d [SCSI] aic7xxx, aic79xx: deinline functions
Deinlines and moves big functions from .h to .c files.
Adds prototypes for ahc_lookup_scb and ahd_lookup_scb to .h files.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-24 09:09:18 -05:00
Denys Vlasenko 62cef8212f [ALSA] sound/pci/rme9652/hdspm.c: stop inlining largish static functions
sound/pci/rme9652/hdspm.c has unusually large number of static inline
functions - 22.

I looked through them and some of them seem to be too big to warrant inlining.

This patch removes "inline" from these static functions (regardless of number
of callsites - gcc nowadays auto-inlines statics with one callsite).

Size difference on 32bit x86:
   text    data     bss     dec     hex filename
  20437    2160     516   23113    5a49 linux-2.6-ALLYES/sound/pci/rme9652/hdspm.o
  18036    2160     516   20712    50e8 linux-2.6.inline-ALLYES/sound/pci/rme9652/hdspm.o

[coding fix by Takashi Iwai <tiwai@suse.de>]

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2008-04-24 12:00:33 +02:00
Denys Vlasenko 7dd73bbcc9 sb1000.c: make const arrays static
This patch replaces automatic constant arrays a-la

    const unsigned char Command0[6] = {0x80, 0x16, 0x00, 0x00, 0x00, 0x00};

with static ones. Size difference for 32bit x86:

text  data   bss     dec     hex filename
5418   129     0    5547    15ab linux-2.6.inline-ALLYES/drivers/net/sb1000.o
5396   129     0    5525    1595 linux-2.6.followup-ALLYES/drivers/net/sb1000.o

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-04-16 20:41:44 -04:00
Denys Vlasenko a8d06342ba sb1000.c: stop inlining largish static functions
drivers/net/sb1000.c has lots of inlined static functions.

Mst of them are used at initialization, wait for some
hardware register to change (wait using yield, sleep etc),
or do slow port-based I/O. Inlining thse "for speed" makes no sense.

This patch removes "inline" from biggest static function
(regardless of number of callsites - gcc nowadays auto-inlines
statics with one callsite).

Size difference for 32bit x86:

text   data    bss    dec    hex filename
6299    129      0   6428   191c linux-2.6-ALLYES/drivers/net/sb1000.o
5418    129      0   5547   15ab linux-2.6.inline-ALLYES/drivers/net/sb1000.o

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-04-16 20:41:43 -04:00
Denys Vlasenko 2cf83afe90 [ATM] drivers/atm/horizon.c: stop inlining largish static functions
drivers/atm/horizon.c has unusually large number
of static inline functions - 36.

I looked through them. Most of them seems to be small enough,
but a few are big, others are using udelay or busy loop,
and as such are better not be inlined.

This patch removes "inline" from these static functions
(regardless of number of callsites - gcc nowadays auto-inlines
statics with one callsite).

Size difference for 32bit x86:
   text    data     bss     dec     hex filename
   8201     180       6    8387    20c3 linux-2.6-ALLYES/drivers/atm/horizon.o
   7840     180       6    8026    1f5a linux-2.6.inline-ALLYES/drivers/atm/horizon.o

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-13 21:54:34 -07:00
Denys Vlasenko 2aee82de52 wavelan_cs: stop inlining largish static functions
Hi John,

Can you please take a look at this patch?

drivers/net/wireless/wavelan_cs.c has unusually large number
of static inline functions - 27.

I looked through them and 20 of them do not seem to warrant inlining.
Some are really big; others call mdelay(1) or busy-wait for a bit
to be set in a hardware register - it's pointless
to optimize such functions for speed.

This patch removes "inline" from these static function
(regardless of number of callsites - gcc nowadays auto-inlines
statics with one callsite).

Size difference for 32bit x86:

   text    data     bss     dec     hex filename
  17020     372       8   17400    43f8 linux-2.6-ALLYES/drivers/net/wireless/wavelan_cs.o
  14032     356       8   14396    383c linux-2.6.inline-ALLYES/drivers/net/wireless/wavelan_cs.o

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
--
vda
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-04-08 15:05:57 -04:00
Denys Vlasenko a5b2db6713 [ATM] drivers/atm/ambassador.c: stop inlining largish static functions
drivers/atm/ambassador.c has unusually large number
of static inline functions - 22.

I looked through them and half of them seem to be too big
to warrant inlining.

This patch removes "inline" from these static functions
(regardless of number of callsites - gcc nowadays auto-inlines
statics with one callsite).

Size difference for 32bit x86:
   text    data     bss     dec     hex filename
  10209    8488       4   18701    490d linux-2.6-ALLYES/drivers/atm/ambassador.o
   9462    8488       4   17954    4622 linux-2.6.inline-ALLYES/drivers/atm/ambassador.o

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-03 14:59:55 -07:00
Denys Vlasenko 1483b8744e [NET]: Add inline intent commentary to dev_alloc_skb().
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-28 15:57:39 -07:00
Denys Vlasenko 9b706aee7d x86: trivial printk optimizations
In arch/x86/boot/printf.c gets rid of unused tail of digits: const char
*digits = "0123456789abcdefghijklmnopqrstuvwxyz"; (we are using 0-9a-f
only)

Uses smaller/faster lowercasing (by ORing with 0x20)
if we know that we work on numbers/digits. Makes
strtoul smaller, and also we are getting rid of

  static const char small_digits[] = "0123456789abcdefx";
  static const char large_digits[] = "0123456789ABCDEFX";

since this works equally well:

  static const char digits[16] = "0123456789ABCDEF";

Size savings:

$ size vmlinux.org vmlinux
   text    data     bss     dec     hex filename
 877320  112252   90112 1079684  107984 vmlinux.org
 877048  112252   90112 1079412  107874 vmlinux

It may be also a tiny bit faster because code has less
branches now, but I doubt it is measurable.

[ hugh@veritas.com: uppercase pointers fix ]

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-09 23:24:09 +01:00
Denys Vlasenko eed4a2aba7 printk.c: use unsigned ints instead of longs for logbuf index
Stop using unsigned _longs_ for printk buffer indexes.  Log buffer is way
smaller than 2 gigabytes and unsigned ints will work too .  Indeed, they do
work nicely on all 32-bit platforms where longs and ints are the same.

With this patch, we have following size savings on amd64:

   text    data     bss     dec     hex filename
   5997     313   17736   24046    5dee 2.6.23.1.t64/kernel/printk.o
   5858     313   17700   23871    5d3f 2.6.23.1.printk.t64/kernel/printk.o

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 10:41:04 -08:00
Denys Vlasenko 9ba99b0d3f [NETFILTER]: ipt_REJECT: properly handle IP options
The current TCP RST construction reuses the old packet and can't
deal with IP options as a consequence of that. Construct the
RST from scratch instead.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:02:30 -08:00
Denys Vlasenko 022748a935 [NETFILTER]: {ip,ip6}_tables: remove some inlines
This patch removes inlines except those which are used
by packet matching code and thus are performance-critical.

Before:

$ size */*/*/ip*tables*.o
   text    data     bss     dec     hex filename
   6402     500      16    6918    1b06 net/ipv4/netfilter/ip_tables.o
   7130     500      16    7646    1dde net/ipv6/netfilter/ip6_tables.o

After:

$ size */*/*/ip*tables*.o
   text    data     bss     dec     hex filename
   6307     500      16    6823    1aa7 net/ipv4/netfilter/ip_tables.o
   7010     500      16    7526    1d66 net/ipv6/netfilter/ip6_tables.o

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:02:29 -08:00
Denys Vlasenko ff85a8082f [CRYPTO] camellia: Move more common code into camellia_setup_tail
Analogously to camellia7 patch, move
"absorb kw2 to other subkeys" and "absorb kw4 to other subkeys"
code parts into camellia_setup_tail(). This further reduces
source and object code size at the cost of two brances
in key setup code.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:22 +11:00
Denys Vlasenko dedcf8b064 [CRYPTO] camellia: Move common code into camellia_setup_tail
Move "key XOR is end of F-function" code part into
camellia_setup_tail(), it is sufficiently similar
between camellia_setup128 and camellia_setup256.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:21 +11:00
Denys Vlasenko acca79a664 [CRYPTO] camellia: Merge encrypt/decrypt routines for all key lengths
unifies encrypt/decrypt routines for different key lengths.
This reduces module size by ~25%, with tiny (less than 1%)
speed impact.
Also collapses encrypt/decrypt into more readable
(visually shorter) form using macros.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:21 +11:00
Denys Vlasenko 2ddae4a644 [CRYPTO] camellia: Code shrink
Remove unused macro params.
Use (u8)(expr) instead of (expr) & 0xff,
helps gcc to realize how to use simpler commands.
Move CAMELLIA_FLS macro closer to encrypt/decrypt routines.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:20 +11:00
Denys Vlasenko d3e7480572 [CRYPTO] camellia: De-unrolling
Move huge unrolled pieces of code (3 screenfuls) at the end of
128/256 key setup routines into common camellia_setup_tail(),
convert it to loop there.
Loop is still unrolled six times, so performance hit is very small,
code size win is big.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:08 +11:00
Denys Vlasenko 1ce73e8d6d [CRYPTO] camellia: Code cleanup
Optimize GETU32 to use 4-byte memcpy (modern gcc will convert
such memcpy to single move instruction on i386).
Original GETU32 did four byte fetches, and shifted/XORed those.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:07 +11:00
Denys Vlasenko 3a5e5f8108 [CRYPTO] camellia: Code cleanup
Rename some macros to shorter names: CAMELLIA_RR8 -> ROR8,
making it easier to understand that it is just a right rotation,
nothing camellia-specific in it.
CAMELLIA_SUBKEY_L() -> SUBKEY_L() - just shorter.

Move be32 <-> cpu conversions out of en/decrypt128/256 and into
camellia_en/decrypt - no reason to have that code duplicated twice.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:07 +11:00
Denys Vlasenko 1721a81256 [CRYPTO] camellia: Code cleanup
Move code blocks around so that related pieces are closer together:
e.g. CAMELLIA_ROUNDSM macro does not need to be separated
from the rest of the code by huge array of constants.

Remove unused macros (COPY4WORD, SWAP4WORD, XOR4WORD[2])

Drop SUBL(), SUBR() macros which only obscure things.
Same for CAMELLIA_SP1110() macro and KEY_TABLE_TYPE typedef.

Remove useless comments:
/* encryption */ -- well it's obvious enough already!
void camellia_encrypt128(...)

Combine swap with copying at the beginning/end of encrypt/decrypt.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:06 +11:00
Denys Vlasenko e2b21b5002 [CRYPTO] twofish: Do not unroll big stuff in twofish key setup
Currently twofish cipher key setup code
has unrolled loops - approximately 70-100
instructions are repeated 40 times.

As a result, twofish module is the biggest module
in crypto/*.

Unrolling produces x2.5 more code (+18k on i386), and speeds up key
setup by 7%:

	unrolled: twofish_setkey/sec: 41128
	    loop: twofish_setkey/sec: 38148
	CALC_K256: ~100 insns each
	CALC_K192: ~90 insns
	   CALC_K: ~70 insns

Attached patch removes this unrolling.

$ size */twofish_common.o
   text    data     bss     dec     hex filename
  37920       0       0   37920    9420 crypto.org/twofish_common.o
  13209       0       0   13209    3399 crypto/twofish_common.o

Run tested (modprobe tcrypt reports ok). Please apply.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:06 +11:00
Denys Vlasenko b9ec0339d8 add consts where appropriate in fs/nls/*
Add const modifiers to a few struct nls_table's member pointers in
include/linux/nls.h and adds a lot of const's in fs/nls/*.c files.

Resulting changes as visible by size:

   text    data     bss     dec     hex filename
 113612  481216    2368  597196   91ccc nls.org/built-in.o
 593548    3296     288  597132   91c8c nls/built-in.o

Apparently compiler managed to optimize code a bit better
because of const-ness.

No other changes are made.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:58 -07:00
Denys Vlasenko 8336793baf [ZLIB]: Move bnx2 driver gzip unpacker into zlib.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:53:57 -07:00
Denys Vlasenko b3448b0bde [BNX2]: factor out gzip unpacker
This patch modifies gzip unpacking code in bnx2 driver so that
it does not depend on bnx2 internals. I will move this code
out of the driver and into zlib in follow-on patch.

It can be useful in other drivers which need to store firmwares
or any other relatively big binary blobs - fonts, cursor bitmaps,
whatever.

Patch is run tested by Michael Chan (driver author).

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:53:57 -07:00
Denis Vlasenko 4277eedd79 vsprintf.c: optimizing, part 2: base 10 conversion speedup, v2
Optimize integer-to-string conversion in vsprintf.c for base 10.  This is
by far the most used conversion, and in some use cases it impacts
performance.  For example, top reads /proc/$PID/stat for every process, and
with 4000 processes decimal conversion alone takes noticeable time.

Using code from

http://www.cs.uiowa.edu/~jones/bcd/decimal.html
(with permission from the author, Douglas W. Jones)

binary-to-decimal-string conversion is done in groups of five digits at
once, using only additions/subtractions/shifts (with -O2; -Os throws in
some multiply instructions).

On i386 arch gcc 4.1.2 -O2 generates ~500 bytes of code.

This patch is run tested. Userspace benchmark/test is also attached.
I tested it on PIII and AMD64 and new code is generally ~2.5 times
faster. On AMD64:

# ./vsprintf_verify-O2
Original decimal conv: .......... 151 ns per iteration
Patched decimal conv:  .......... 62 ns per iteration
Testing correctness
12895992590592 ok...        [Ctrl-C]
# ./vsprintf_verify-O2
Original decimal conv: .......... 151 ns per iteration
Patched decimal conv:  .......... 62 ns per iteration
Testing correctness
26025406464 ok...        [Ctrl-C]

More realistic test: top from busybox project was modified to
report how many us it took to scan /proc (this does not account
any processing done after that, like sorting process list),
and then I test it with 4000 processes:

#!/bin/sh
i=4000
while test $i != 0; do
    sleep 30 &
    let i--
done
busybox top -b -n3 >/dev/null

on unpatched kernel:

top: 4120 processes took 102864 microseconds to scan
top: 4120 processes took 91757 microseconds to scan
top: 4120 processes took 92517 microseconds to scan
top: 4120 processes took 92581 microseconds to scan

on patched kernel:

top: 4120 processes took 75460 microseconds to scan
top: 4120 processes took 66451 microseconds to scan
top: 4120 processes took 67267 microseconds to scan
top: 4120 processes took 67618 microseconds to scan

The speedup comes from much faster generation of /proc/PID/stat
by sprintf() calls inside the kernel.

Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:52 -07:00
Denis Vlasenko b39a734097 vsprintf.c: optimizing, part 1 (easy and obvious stuff)
* There is no point in having full "0...9a...z" constant vector,
  if we use only "0...9a...f" (and "x" for "0x").

* Post-decrement usually needs a few more instructions, so use
  pre decrement instead where makes sense:
-       while (i < precision--) {
+       while (i <= --precision) {

* if base != 10 (=> base 8 or 16), we can avoid using division
  in a loop and use mask/shift, obtaining much faster conversion.
  (More complex optimization for base 10 case is in the second patch).

Overall, size vsprintf.o shows ~80 bytes smaller text section
with this patch applied.

Signed-off-by: Douglas W Jones <jones@cs.uiowa.edu>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:52 -07:00
Denis Vlasenko 7b75b990e3 [SCSI] aic7xxx: fix byte I/O order in ahd_inw
Comment says "Read high byte first as some registers increment..."
but code doesn't guarantee that, I think:
	return ((ahd_inb(ahd, port+1) << 8) | ahd_inb(ahd, port));
Compiler can reorder it.

Make the order explicit.

Signed-off-by: Denis Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>

Fixed rejections and added aic7xxx code
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-10-01 15:03:38 -05:00
Denis Vlasenko c7aed17902 drm: i810_dma.c: fix pointer arithmetic for 64-bit target
First warning result from open-coded PTR_ERR,
the rest is caused by code like this:

*(u32 *) ((u32) buf_priv->kernel_virtual + used)

I've also fixed a missing PTR_ERR in i830_dma.c

Signed-off-by: Dave Airlie <airlied@linux.ie>
2006-09-22 05:32:33 +10:00