A recent buglet in the <meminfo> interface, where many
delta values could legitimately be negative, suggested
a review of this module where a minus was forced to 0.
As it turns out, there are two delta items that indeed
could be negative. They involve the current processes.
So henceforth, DELTA_PROC_BLOCKED & DELTA_PROC_RUNNING
will now be allowed to go negative. I believe that all
other items can only grow. But, if we find more later,
at least the adaptation approach has been established.
[ this whole business of checking for less than zero ]
[ harks back to an old kernel anomaly where negative ]
[ tics were sometimes experienced. top was affected. ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
When the code for DELTA values (among other stuff) was
stolen from the recently revised <stat> interface, the
concept of ever growing values was propagated too. But
here we must manage both growing and shrinking values.
Thus former protections against a negative delta don't
have any place in this module and are hereby banished.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Thus function returns a pointer, not an int, so if there is
an error return NULL and not -errno.
proc/meminfo.c: In function ‘procps_meminfo_select’:
proc/meminfo.c:994:20: warning: return makes pointer from integer
without a cast [-Wint-conversion]
return -ENOMEM;
References:
commit 407f1b71de
This represents the refinement of this interface after
the <stat> API was redesigned. We now follow a pattern
of 'get' for single item retrieval & 'select' for when
multiple items are desired, with just 1 function call.
And again following the <stat> lead this interface now
provides for delta values encompassing most items. The
reason I went cuckoo nuts with those deltas is because
they are essentially free. At the cost of a little RAM
and just one memcpy there's no other price to be paid.
Signed-off-by: Jim Warner <james.warner@comcast.net>
In the commit referenced below it was acknowledged the
procps_stat_get() function will intentionally restrict
returned values by excluding DELTA items among others.
Upon reflection that decision seemed rather arbitrary,
and so has now been lifted. And, while the initial use
of a DELTA will return 0, subsequent calls to that get
function will now return the difference (providing one
second, at least, has elapsed between any such calls).
Reference(s):
. reference to design decisions
commit abc71a46ad
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit is just my usual tweaking after an initial
submission, once the dust has settled & some more desk
checking was performed. Here are the changes included:
. get function need not check the 'stat_was_read' flag
( first time in save_sec == 0 so branch always taken )
. some table logic appeared outside the proper section
. cleanup_stack's loop made to work like assign_result
. eliminated an include of procps.h from stat.h header
. removed 'ext_numitems' from the stacks_extent struct
. changed the alignment of three prototypes for stat.h
. reorganized the pointers for 'stacks_extents' struct
. improved types indentation in header for readability
. lastly, some really gratuitous changes made to align
- comments within that private 'stacks_alloc' function
Signed-off-by: Jim Warner <james.warner@comcast.net
This commit represents a complete redesign of the stat
interface. Gone are the confusing 8 separate accessors
along with their 2 additional read functions. In their
place we have just 3 accessors, with no read required.
That old interface also suffered an inflexibility with
respect to structures. Now we deal with an unchanging
standard 'result' struct enabling future changes where
the binary interface will no longer need to be broken.
And gone is that former unnecessary typedef, used when
dealing with jiffies. Now the standard C type is used.
Our new API also adds some brand new functionality. If
a caller plans to employ successive 'select' or 'reap'
invocations, then delta values are available (which is
actually only what that top program is interested in).
At some future point a 'sort' function could be easily
introduced to complement the 'reap' function. However,
I saw no need for it at present and so it was omitted.
There were several design decisions which everyone may
not agree with. In support I'll offer these rationals:
. The 'get' function returns a signed long long result
which means a potential loss of some significance. But
I felt the ability to distinguish actual errors (minus
values) from true zero results were worth such a risk.
. The DELTA item enumerators were also made signed and
smaller than their parents. And they are intentionally
grouped as last so as to emphasize those distinctions.
. The SYS type items were excluded from the new 'reap'
function. It would not make sense to duplicate them in
each results stack. They're limited to 'get'/'select'.
. By the same token, some items (DELTA, etc.) will not
be allowed under that 'get' routine. That function was
already open to significant internal overhead (through
subsequent calls like in vmstat.c). That is why it has
been limited via 1 second between reads of /proc/stat.
Lastly, when we finally get around to documenting this
interface there's a real potential toe stubber when it
comes to the numa node portion. The libnuma.so doesn't
really provide any means to retrieve the active nodes.
Thus, any total reported by <stat> is just the highest
node number plus one, as reported by the numa library.
Any unused/inactive nodes are identified through these
. PROCPS_STAT_TIC_ID shows as PROCPS_STAT_NODE_INVALID
By the same token after the STAT_REAP_CPUS_ONLY 'reap'
. PROCPS_STAT_TIC_NUMA_NODE = PROCPS_STAT_NODE_INVALID
Reference(s):
http://www.freelists.org/post/procps/newlib-stat-interface
Signed-off-by: Jim Warner <james.warner@comcast.net>
During work on the new <stat> interface the typedef of
jiffs was eliminated along with the clang warning. The
exact same warning in sysinfo.h now goes bye-bye also.
Reference(s):
./proc/sysinfo.h:16:28: warning: redefinition of typedef 'jiff' is a C11 feature [-Wtypedef-redefinition]
typedef unsigned long long jiff;
Signed-off-by: Jim Warner <james.warner@comcast.net>
The previous commit did not take into account operator evaluation
order so always gave 0. Fixed the macro and added some checks for
the macro.
References:
commit 9abf7d879d
Linux release numbers are x.y.z we assumed but never protected
against x> 0x7fff and y,z > 0xff before.
Linux release in 1991, 1 major release per 6 years so we're fine
until 7452, unless they do way too many minor rels (max being 39)
procps_uptime, previously just plain uptime() used to put the
uptime (as a double) in the first argument and return uptime
(as an int).
It meant if you ran
myuptime2 = procps_uptime(&myuptime1, NULL);
You might get different results for myuptime1 and myuptime2 because
they are different types.
Most library calls use the return value to return the status,
procps_uptime was in the middle.
Until now.
This function will return 0 on success. If you want (for whatever
reason) uptime as an int then cast it.
All of the procps binaries didn't use the return value for uptime
except ps which set a variable to it but never used it anywhere.
While procps_diskstat_ref and procps_diskstat_unref were declared
they actually weren't implemented in the library. Linking some
binary that used these functions gave the following errors:
CCLD vmstat
vmstat.o: In function `disksum_format':
vmstat.c:719: undefined reference to `procps_diskstat_unref'
vmstat.o: In function `diskformat':
vmstat.c:591: undefined reference to `procps_diskstat_unref'
In an attempt to normalize the 'stat' interface, we'll
first shed any reminders of the old readproc interface
by changing file names to be more descriptive & brief.
Signed-off-by: Jim Warner <james.warner@comcast.net>
After the commit referenced below the potential exists
for a SEGV (resulting from an out-of-bounds Item_table
reference if PROCPS_PIDS_physical_end is encountered).
So this patch eliminates that PROCPS_PIDS_physical_end
as no longer necessary and completes the task of using
PROCPS_PIDS_logical_end as a sole necessary fencepost.
Reference(s):
commit e7585992d9
Without breaking either ABI or API just rearrange some
stuff to provide a little more consistent source file.
[ these were prompted by some work on the <stat> API ]
[ in preparation for him borrowing some of our code. ]
Reference(s):
Signed-off-by: Jim Warner <james.warner@comcast.net>
Generalised the library API tests and created a common
test-runner. Instead of copy and pasting the same code in
each time.
First cut of pids API test, for _new so far.
Remove a remnant of this new API's evolution. Here we
no longer fill stacks, rather we reap and select them.
Signed-off-by: Jim Warner <james.warner@comcast.net>
By co-mingling both external/internal identifiers with
actual implementation code, potential future additions
to our API would have been considerably more difficult.
So, this patch will now rely solely on internal/hidden
identifiers serving as fenceposts in validation logic.
And if the following convention is used for new fields
we will maintain that enumerator alphabetic ordering a
a little longer (even though 2 user fields now don't):
. PROCPS_PIDS_XTRA_FOO_A, PROCPS_PIDS_XTRA_FOO_B, etc.
Reference(s):
http://www.freelists.org/post/procps/me-too-newlib,7
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>
escaped_copy(): only appears in ps, moved to ps/output.c
escape_strlist() only used in escape.c made static
escape_command() used in library, made internal
procps.h no longer includes escape.h
escape_str() used by library and ps so needs to be exported
definition put into procps.h including the odd define required.
Far from ideal to have it this way, will look at it another time
to have it all in, all out or split nicer so its not in the API;
perhaps a lib/ file?
readproc still had some of the old API hanging around that
was good while we were trying it out, but its time to say
goodbye:
readproc.h removed from public procps.h header file
enum ns_type - not used - removed
get_ns_name() - not defined - removed
get_ns_id() - not defined - removed
PROCTAB proc_t only used internal to library
readproctab() and 2,3 friends not used - removed
proc_data_t was used by readproctab23() - removed
readtask() - not used - removed
read_cmdline() - copy,renamed and made generic - remove original
freeproc() - not used - removed
get_proc_status - not used - removed, however there should be
a new function created that does this. Given a PID return data
about it instead of scanning the entire procfs. Maybe it already does.
Left as internal-to-library only functions:
readproc(), readeither(), look_up_our_self(), openproc(), closeproc()
Updated libprocps.sym to export only what we use.
Now that the conditional OOMEM_ENABLE has been removed
and, after reviewing current library support, it turns
out we've been using a deprecated /proc/<pid>/oom_adj.
What we should use instead is that more recent tunable
/proc/<pid>/oom_score_adj. This new field will provide
a range of -1000 thru +1000 (former was -17 thru +15).
Reference(s):
. removal of misguided OOMEM_ENABLE
commit 64238730fa
. linux, partial oom_adj revert (Nov, 2012)
commit fa0cbbf145aabbf29c6f28f8a11935c0b0fd86fc
. linux, removal oom_adj (Oct, 2012)
commit 01dc52ebdf472f77cca623ca693ca24cfc0f1bbe
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
Multiple scanf()s use the GNU-permitted %Lu. This is not supported in
other libraries and isn't to the POSIX specification. The L modifier
is only used for floats in POSIX.
Replacing %Lu with %llu is the same for GNU libc (scanf(3) says as much)
but means other libraries will work fine.
From master commit da715e3
References:
http://pubs.opengroup.org/onlinepubs/009695399/functions/fscanf.html
Beginning with linux-4.5, the following new fields are
being added under that /proc/<pid>/status pseudo file:
. RssAnon - size of resident anonymous memory
. RssFile - size of resident file mappings
. RssShmem - size of resident shared memory
This patch just represents the initial library and top
support, sharing a commit message with 2 more patches.
p.s. locked resident memory support was also added but
isn't directly related to the kernel 4.5 enhancements.
Reference(s):
commit 1f8e41d019
Signed-off-by: Jim Warner <james.warner@comcast.net>
Summarized below, miscellany addressed in this commit:
. deleted extraneous newline(s) for consistent spacing
Signed-off-by: Jim Warner <james.warner@comcast.net>
When reference counts were added to some string fields
the 3 true string vector fields were not duplicated as
were those other fields. Instead they were supposed to
disallow a duplicate stack reference beyond the first.
However, the actual implementation gave NULL for every
true vector field whenever such items were duplicated.
More importantly, such true string vector fields never
considered references to the shared proc_t source root
which would have forced the conversion of such vectors
into a single string form via the '_CVT' library flag.
So this commit restores the intended outcome with true
string vectors. There's only 1 valid reference allowed
and duplicates and converted fields will yield a NULL.
Signed-off-by: Jim Warner <james.warner@comcast.net>
While not changing generated code this commit corrects
one free reference from 'str' to a more proper 'strv'.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Ok, here is that rather major internal redesign hinted
at in the three previous commits. Its need was quickly
revealed after adapting top then attempting to display
newly added 'CGNAME' fields and an existing 'CGROUPS'.
That very quickly generated a SEGV. And the reason was
just as quickly recognized. Both fields relied on that
proc_t.cgroup member yet whichever result structure is
first in a stack is the one which assumes ownership of
of the vectored sting by resetting its cgroup to NULL.
So this commit introduces reference counting for a few
of the fields in the proc_t. Specifically there are 17
entries in the Item_table dealing with strings/vectors
where ownership is transferred to newlib. Now whenever
such fields are represented more than once in a stack,
the strings will be duplicated instead of transferred.
In this way we can generally remain optimized avoiding
string copies, yet still accommodate them when needed.
There's an exception to this scheme: those true string
vectors (CGROUP_V, CMDLINE_V and ENVIRON_V). When such
fields are duplicated in a stack the result structures
beyond the first will be set to NULL, which the caller
will (should) already be equipped to deal with anyway.
Signed-off-by: Jim Warner <james.warner@comcast.net>
The ps program was modified to print the control group
names, based on the library provided list of all those
control groups to which a process belongs. But this is
probably something the newlib should be doing for all.
So this commit borrows the ps approach to cg names and
thus will make that available to all future consumers.
[ but stay tuned! there is a commit coming soon that ]
[ represents a rather major internal redesign, which ]
[ was prompted by the ps and top adaptation testing. ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
The above function was the sole public function in the
<pids> interface to use the word 'stacks' in its name.
All of the others dealt exclusively with their duties,
So this commit normalizes that outlier by renaming it.
Signed-off-by: Jim Warner <james.warner@comcast.net>
The above function had been disabled via '#if 0' so as
to prevent a compiler warning. But it really should be
called by that 'procps_pids_read_shut' function rather
than it duplicating/reinventing the same logic itself.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Gosh, just because nobody uses some newlib provision I
guess, since it is being offered, it ought to actually
be tested at some point. Well, that point just arrived
and guess what? A surprise: some bugs were discovered.
The procps_pids_select function established a for loop
wherein readproc is called until the passed 'maxthese'
limit. Unfortunately this was incorrect for 2 reasons:
1. For PROCPS_FILL_PID results are limited by what the
oldlib finds, having established the pid list at open.
Total found already cannot exceed a passed 'maxthese';
2. With PROCPS_FILL_UID, returned results could exceed
a 'maxthese' thus making the for loop incorrect again.
[ plus yours truly neglected to forward the required ]
[ UIDs total to our old library, another oops biggie ]
In summary: the loop should have been forever, exiting
only when all those identified procs had been located.
So, while addressing those bugs, I've consolidated all
the retrieval code (initialize, iterate, summarize) in
a single helper function which will now serve both the
procps_pids_reap and select functions. And as a result
those guys were reduced to quite trivial housekeeping.
This patch, hopefully, completes the normalization for
reap/select (fill), which began with references shown.
Reference(s):
commit 0c953eccc5
commit 747dfc5987
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch contains the following minor modifications:
. When assigning to boot_seconds from a double, a cast
to 'unsigned long' was employed that in reality should
have been 'unsigned long long'. But, on second thought
it's probably best if the compiler makes the decision.
. Results for ID_TGID do not require an 'f_status' flg
since both tid and tgid will be available by virtue of
the 'simple_nextpid' function normal operations. Thus,
that flag has been removed from the <pids> Item_table.
. When the pids_stacks structure was eliminated with a
change to the alloc/dealloc functions in the reference
below, several casts became redundant and are removed.
Reference(s):
commit 747dfc5987.
Signed-off-by: Jim Warner <james.warner@comcast.net>
After simplifying that select/fill interface, there is
no longer a need for public 'alloc' & 'dealloc' stacks
functions. There is now only one instance of stacks as
an input parameter found in procps_pids_stacks_sort().
But sorting 'empty' stacks serves no possible purpose.
So this commit retains both functions, since they will
still be needed, but designates them private (static).
Additionally, with their demise we will eliminate that
pids_stacks structure from the header file, internally
using what always was the true 'stacks_extent' struct.
Signed-off-by: Jim Warner <james.warner@comcast.net>
After wrestling with the conversion of both top and ps
the differences between reap (all) & fill (select) has
become increasingly inconvenient. So this patch simply
normalizes that API making returned results identical.
The former procps_pids_stacks_fill identifier will now
be known as procps_pids_select which serves as logical
counterpart to the existing procps_pids_reap function.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Shoot, here's yet another bow to ps needs. But it's ok
because it makes a lot of sense. Rather than force all
users into their own calculations do but it once here.
As an aside this need arose during ps testing when the
sorts were using TIME_START or TICS_ALL. That was just
fine for almost every need except 'etime' plus 'time'.
That 'etime' was sorting the opposite of what's wanted
when using TIME_START (of course) while 'time' yielded
some weird ordering because TICS_ALL was too granular.
Signed-off-by: Jim Warner <james.warner@comcast.net>
While not documented in the man page, ps allows 'tty4'
as a valid output specifier complimenting 'tty8' & its
derivatives. So, in order to eliminate a dev_to_name()
call in the ps program the library will now offer this
abbreviated tty version (consisting of a number only).
Signed-off-by: Jim Warner <james.warner@comcast.net>
The 'PROCPS_PIDS_extra' enumerator already enjoys some
special place wherein it's zeroed with each iteration.
This patch simply extends the special handling to also
include support for sorting. It will be treated as the
'ull_int' data type, since that encompasses the entire
scope of that union within all pids_result structures.
[ plus, we've also corrected the actual 'extra' name ]
This change was prompted by the conversion of ps which
needs that enumerator to store the former 'pcpu' data,
so it will be available for sorting (not for display).
Signed-off-by: Jim Warner <james.warner@comcast.net>
The way that the passed sort order was validated would
allow the invalid 0 to fall between the sofa cushions.
So this patch will simply close that former oversight.
Signed-off-by: Jim Warner <james.warner@comcast.net>
As part of the push to remove the old API, 3 more old calls were
deleted from the library. Now all someone needs to do is fix ps
and we're largely done.
The values of PROCPS_SORT_ASCEND & PROCPS_SORT_DESCEND
were a tad unintuitive. This patch will just make them
a more natural +1 for ascending and -1 for descending.
[ plus it still allows that fast path multiplication ]
[ instead of a comparison for signed numbers/strings ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
After peeking at possible conversion of the ps program
it appeared that we may ultimately need the concept of
a 'static' pids_stack in suport of look_up_our_self().
In other words, one not impacted by procps_pids_reset.
This patch simply sets the stage for that possibility.
Signed-off-by: Jim Warner <james.warner@comcast.net>
