Even though we we had to abandon the master branch top
multi-thread effort and even though the newlib version
of a multi-threaded top provides no real benefit, that
whole exercise was not wasted. Rather, it has revealed
some deficiencies in our library which this addresses.
If two or more threads in the same address space tried
to use procps_loadavg or procps_uptime simultaneously,
there's a chance they would experience problems due to
thread-unsafe functions our library called internally.
So, this patch switches them for thread-safe versions.
[ along the way we will also make that procps_uptime ]
[ initialization of his 'up' & 'idle' variables mean ]
[ something by delaying the -ERANGE return a little. ]
Reference(s):
https://www.freelists.org/post/procps/a-few-more-patches,7
Signed-off-by: Jim Warner <james.warner@comcast.net>
Even though we we had to abandon the master branch top
multi-thread effort and even though the newlib version
of a multi-threaded top provides no real benefit, that
whole exercise was not wasted. Rather, it has revealed
some deficiencies in our library which this addresses.
If two or more threads in the same address space tried
to access the same api simultaneously, there is a good
chance some function-local static variables will yield
some of those renowned unpredictable results. So, this
patch protects them with the '__thread' storage class.
Reference(s):
https://www.freelists.org/post/procps/a-few-more-patches,7
Signed-off-by: Jim Warner <james.warner@comcast.net>
With the 4 header files removed in the previous patch,
this commit just changes all those obsolete references
to that new consolidated 'misc.h' header file instead.
Signed-off-by: Jim Warner <james.warner@comcast.net>
While that old master branch library may utilize those
memory allocation functions found in the alloc module,
it was inappropriate for this newlib branch to subject
callers to a stderr message followed by an early exit.
Of course, the old libprocps offered a message handler
override provision (xalloc_err_handler) but that, too,
would seem to be inappropriate for our modern library.
[ remember the battles fought with that damn libnuma ]
So, this commit will tweak those old inherited sources
setting the stage for standardized return values/errno
settings in connection with a memory allocation error.
------------------------------------------------------
Along the way, we'll address the following miscellany:
. Completely eliminate usage of anything from alloc.h.
This, of course, entails our own error checking of the
alternative allocation calls from stdlib.h & string.h.
. Eliminate use of the strdup function where possible,
as with 'procps_uptime' and 'procps_loadavg' routines.
. Whack some obsolete code (getslabinfo) in sysinfo.c.
Signed-off-by: Jim Warner <james.warner@comcast.net>
[ plus we also play catch up on some earlier changes ]
[ that impacted skill.c, after using --enable-skill! ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
Unfortunately, reading that '/proc/sys/kernel/pid_max'
file returns a newline, which we will now account for.
[ also, we should use the existing dedicated buffer ]
Reference(s):
. original 'procps_pid_length' introduction
commit ccb6ae8de1
Signed-off-by: Jim Warner <james.warner@comcast.net>
The includes used to define a lot of things a library include
should not. It was also a bit messy what was exposed in the library
and what was not.
get_pid_digits -> procps_pid_length and exported correctly
MALLOC attribute move into relevant .c files
NORETURN attribute moved to relevant .c, not used in library
PURE attribute removed, it wasn't used
KLONG/KLF/STRTOUKL were fixed for long, so now just use long
HIDDEN attribute removed. It was for 3 functions. The PROCPS_EXPORT
seems to do the same (opposite) thing.
likely/unlikely removed from most places, its highly debateable
this does anything useful as CPUs have gotten smarter about branches.
Re-arranged the includes, ALL external programs should just #include
<proc/procps.h> then proc/procps.h includes headers for files that
have exported functions. procps.h and the headers it includes should
not use items that are not exportable (e.g. hidden functions or
macros) they go in procps-private.h
[ but most definitely not all of them by a long shot ]
Reference(s):
proc/diskstat.c:186:17: warning: unused variable 'is_disk' [-Wunused-variable]
int retval, is_disk;
^
proc/namespace.c:110:1: warning: control may reach end of non-void function [-Wreturn-type]
}
^
proc/readproc.c:1131:50: warning: address of array 'ent->d_name' will always evaluate to 'true' [-Wpointer-bo
if(unlikely(unlikely(!ent) || unlikely(!ent->d_name))) return 0;
~~~~~~^~~~~~
proc/readproc.c:1158:50: warning: address of array 'ent->d_name' will always evaluate to 'true' [-Wpointer-bo
if(unlikely(unlikely(!ent) || unlikely(!ent->d_name))) return 0;
~~~~~~^~~~~~
proc/sysinfo.c:45:12: warning: unused variable 'stat_fd' [-Wunused-variable]
static int stat_fd = -1;
^
proc/sysinfo.c:49:12: warning: unused variable 'meminfo_fd' [-Wunused-variable]
static int meminfo_fd = -1;
^
proc/sysinfo.c:51:12: warning: unused variable 'vminfo_fd' [-Wunused-variable]
static int vminfo_fd = -1;
^
proc/sysinfo.c:53:12: warning: unused variable 'vm_min_free_fd' [-Wunused-variable]
static int vm_min_free_fd = -1;
^
proc/uptime.c:157:12: warning: unused variable 'realseconds' [-Wunused-variable]
time_t realseconds;
^
proc/uptime.c:158:16: warning: unused variable 'realtime' [-Wunused-variable]
struct tm *realtime;
^
vmstat.c:574:20: warning: format specifies type 'unsigned int' but the argument has type 'unsigned long' [-Wformat]
DSTAT(PROCPS_DISKSTAT_READ_TIME),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
vmstat.c:578:20: warning: format specifies type 'unsigned int' but the argument has type 'unsigned long' [-Wformat]
DSTAT(PROCPS_DISKSTAT_WRITE_TIME),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
watch.c:230:7: warning: variable 'endptr' is uninitialized when used here [-Wuninitialized]
if (*endptr == '\0') set_ansi_attribute(0); /* [m treated as [0m */
^~~~~~
Signed-off-by: Jim Warner <james.warner@comcast.net>
The calls for reading diskstat have been moved out of
sysinfo and into new files diskstat.[ch] These new
library calls follow the standard pattern for the
new libprocps.
vmstat is updated to use the new API and also got
the weighted IO time added.
vmstat -p previously would only show partitions, not
disks. There does not appear to be any good reason to
artifically deny a user to use this command on a disk,
rather than a partition so this restriction was lifted.
I also realised using int for devid means you can send
the library negative numbers, the index uses unsigned int.
Other similiar calls will need to be fixed too.
Signed-off-by: Craig Small <csmall@enc.com.au>
This is actually a systemcall getpagesize(2) or it is defined
in configure using a variety of methods, including a default
hard coded value as a last resort.
There is no need to have this in libprocps
Removed the printf_uptime, binaries can do printf easily enough.
sprint_uptime split into two as there wasn't a lot of common
code
sprint_uptime(): old style uptime line
sprint_uptime_short(): short new style "uptime -p"
Hertz_hack needed this, no sane system uses the code (I think)
so just assume 100 like we do in FreeBSD.
Added function procps_linux_version() which used to be an
exported integer instead. Also changed the method of obtaining
the linux version (more correctly the os release) to use a specific
procfs entry. This works for both Linux and FreeBSD.
Under a lxc container, the /proc/meminfo 'MemFree' and
'MemAvailable' amounts will be equal, unless memory is
being limited via cgroups in which case 'MemAvailable'
could exceed that for 'MemTotal'. And when a container
has been nested, there exist additional memory quirks.
A program might then display used or available amounts
greater than total memory (assuming unsigned honored),
or negative values (should a signed cast be employed).
This anomaly primarily impacted the top and free pgms.
Thus, two simple sanity checks have been introduced to
avoid any illogical kb_main_available or kb_main_used.
( Busybox top & free also display anomalous although )
( different results when running in a lxc container. )
Reference(s):
https://bugzilla.redhat.com/show_bug.cgi?id=1153817
Signed-off-by: Jim Warner <james.warner@comcast.net>
Let's not report zero for kb_main_available when older
kernels don't have MemAvailable. Instead, if we simply
duplicate the 'free' amount we can avoid all ancillary
problems, such as those involving top's graphing mode.
Reference(s):
http://www.freelists.org/post/procps/kb-main-available-etc,3
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit just ensures recalculation of some amounts
for iterative processes, like top. It also trades some
repeated runtime calls to sysconf for a one time cost.
Reference(s):
http://www.freelists.org/post/procps/systemd-support-to-library,7
. fall-back calculations
commit b779855cf1
Signed-off-by: Jim Warner <james.warner@comcast.net>
The stderr message regarding ELF notes appears on some
systems (openSUSE-13.1 for example) but I have not yet
isolated why. Since at startup we go on to determine a
Hertz value the old fashion way, this patch just turns
off the useless message until the cause is understood.
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit adds support for fallback calculation
of the MemAvailable field if not exported by the
kernel. The MemAvailable field appeared in kernel
3.14, but it's possible to calculate it from other
fields since 2.6.27 (splitLRU changes).
This commit adds a new switch -a/--available that
appends a new column called 'available' to the
output. The column displays an estimation
of how much memory is available for starting
new applications, without swapping. Unlike the data
provided by the 'cached' or 'free' fields, this
field takes into account page cache and also that
not all reclaimable memory slabs will be reclaimed
due to items being in use.
The subtraction was marked as reinforcing the misconception,
that memory in the page cache can be considered free.
The Cached value is not a sum of page cache and tmpfs,
as the tmpfs memory lives in the page cache and therefore
it's an inseparable part of it.
tmpfs has become much more widely used since distributions use it for
/tmp (Fedora 18+). In /proc/meminfo, memory used by tmpfs is accounted
into "Cached" (aka "NR_FILE_PAGES",
http://lxr.free-electrons.com/source/mm/shmem.c#L301 ).
The tools just pass it on, so what top, free and vmstat report as
"cached" is the sum of page cache and tmpfs.
free has the extremely useful "-/+ buffers/cache" output. However, now
that tmpfs is accounted into "cached", those numbers are way off once
you have big files in /tmp.
Fortunately, kernel 2.6.32 introduces "Shmem", which makes tmpfs memory
usage accessible from userspace (
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=4b02108ac1b3354a22b0d83c684797692efdc395 ).
This patch substracts Shmem from Cached to get the actual page cache
memory. This makes both issues mentioned above disappear. For older
kernels, Shmem is not available (hence zero) and this patch is no-op.
Additionally:
* Update the man pages of free and vmstat to explain what is happening
* Finally drop "MemShared" from the /proc/meminfo parser, it has been
dead for 10+ years and is only causing confusion ( removed in kernel
2.5.54, see
https://git.kernel.org/cgit/linux/kernel/git/tglx/history.git/commit/?id=fe04e9451e5a159247cf9f03c615a4273ac0c571 )
vmstat -d or vmstat -p would crash mysteriously under different
circumstances. The problem was eventually tracked down to /sys not
being mounted which meant is_disk() always returned false.
The partition would then be attempted to be linked to a non-existent
disk causing a segfault.
vmstat will now not link to a disk if none exists.
The change in testing will skip those tests when /sys/block doesn't
exist.
Many thanks to Daniel Schepler for his analysis and suggestions.
Bug-Debian: http://bugs.debian.org/736628
Previously the shared memory column was always zero
for 2.6 series kernels (and later) due to the fact,
that the value was taken from the MemShared entry
that disappeared with 2.6 series kernels.
Later a new Shmem entry appeared in the /proc/meminfo
file and the 'shared' column now displays either
the MemShared or the Shmem value (depending on their
presence - the presence is mutually exclusive).
If none of the two entries is exported by the kernel,
then the column is zero.
An unpleasant thing happened when I comitted the shmem support
for the 'free' tool. We already had a merge request from
Adrian Brzezinski in the queue, doing exactly the same.
As Adrian deserves credits, I'm reverting the change
and re-applying with the next commit in order to make
him a part of the project history.
Previously the shared memory column was always zero
for 2.6 series kernels (and later) due to the fact,
that the value was taken from the MemShared entry
that disappeared with 2.6 series kernels.
Later a new Shmem entry appeared in the /proc/meminfo
file and the 'shared' column now displays either
the MemShared or the Shmem value (depending on their
presence - the presence is mutually exclusive).
If none of the two entries is exported by the kernel,
then the column is zero.
It seems in some cases procs_running field of /proc/stat can contain 0 even if vmstat itself is running. At least this can be reproduced on Linux 3.9.3 compiled with BFS scheduler.
Since getstat() decrements value of procs_running by 1, we get overflow:
$ vmstat 1
procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu----
r b swpd free buff cache si so bi bo in cs us sy id wa
0 0 667732 918996 57376 911260 21 30 36 40 98 45 14 82 4 1
4294967295 0 667728 916716 57376 911264 8 0 8 0 1958 3733 28 7 65 1
0 0 667700 915996 57376 911416 24 0 152 0 1735 3600 23 5 71 1
4294967295 0 667700 915872 57376 911392 0 0 0 0 1528 3165 21 4 76 0
Function getbtime() currently makes the assumption that btime==0 equals
btime not being present in /proc/stat. This is not quite accurate, as
timestamp 0 is, in fact, also a valid time (Epoch), and /proc/stat may
report it as such.
We introduce a flag to indicate whether btime was found in /proc/stat.
In this way, btime==0 becomes a valid case, provided /proc/stat
actually reports this as the boot time.
procps can still detect the case of btime actually not being reported
by the kernel.
Signed-off-by: Markus Mayer <mmayer@broadcom.com>
An earlier commit attempted to cleanse our environment
of all useless trailing whitespace. But the effort did
not catch 'empty' lines with a single space before ^J.
This commit hopefully finishes off the earlier effort.
In the meantime, let's pray that contributors' editors
are configured so that such wasted crap is disallowed!
Reference(s):
commit fe75e26ab6
Signed-off-by: Jim Warner <james.warner@comcast.net>
The entire tree's polluted with inappropriate trailing
whitespace. This commit rids our environment of all of
those useless keystrokes. Unfortunately, it sure ain't
a permanent solution and requires every contributor to
instruct their editor(s) to prevent or eliminate them.
Plus it's strongly recommended we all insert something
like what's shown below to our '.gitconfig' file so as
to provide at least some warnings when we try to apply
any patches (git am) that do contain the #@!%& things!
References(s):
~/.gitconfig excerpt ---------------------------------
[core]
whitespace = trailing-space, space-before-tab, blank-at-eof
[apply]
whitespace = warn
--------------------------------- ~/.gitconfig excerpt
Signed-off-by: Jim Warner <james.warner@comcast.net>
The problem is that in ./proc/sysinfo.c uptime(), it is not
considered that the "savelocale" string is overwritten by the
subsequent call to setlocale(). Hence restoring the locale later on
won't work this way. "savelocale" ought to be a copy of the string
pointed to by setlocale()'s return-value.
Bug-Redhat: https://bugzilla.redhat.com/show_bug.cgi?id=548711
Backported-by: Sami Kerola <kerolasa@iki.fi>
