Commit Graph

20 Commits

Author SHA1 Message Date
Jim Warner
4f2fe6411e library: expand fields and break an ABI, <MEMINFO> api
The immediately prior commit demonstrated how our APIs
might be expanded in at some point in the future while
maintaining binary compatibility in previous programs.

However, since we've yet to release the 1st version of
our new library, there's no need to violate alphabetic
ordering just yet. So, this patch restores that order.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-08-16 21:08:27 +10:00
Jim Warner
09e1886c9e library: expand fields yet maintain ABI, <MEMINFO> api
With the 4.8 kernel, 2 new fields will be added to the
meminfo pseudo file. This commit, soon to be replaced,
is intended as an example of how such changes might be
incorporated plus still maintain binary compatibility.

This actually goes further than is strictly necessary,
by retaining meminfo_item ordering for 'set' functions
and the creation of hash table entries. However, there
is only 1 true requirement, that of Item_table entries
which must always agree exactly with item enumerators.
All of the other changes could be done alphabetically.

Ok, so what happens when an old program encounters the
new expanded meminfo items? Well, if it was thoroughly
tested against an old library, it won't even see those
new fields. On the other hand, if it somehow exceeds a
previous MEMINFO_logical_end, then it will just get an
extra result structure or two, with no real harm done.

[ this patch is being replace by the very next patch ]
[ so that our iniitial newlib release can maintain a ]
[ strict alphabetic ordering in all areas initially! ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-08-16 21:08:27 +10:00
Jim Warner
bef8c7fb70 library: ensure that all those 'GET' macros are robust
When users call the native 'get' functions they have a
responsibility to check that the result struct address
was indeed returned. But when using those 'GET' macros
there was no protection for possible NULL dereference.

So this patch will add some protection for a potential
failure of an underlying 'get' function. And should it
occur then those 'GET' macros will just return a zero.

Plus, we'll also mirror that behavior in the debugging
header should the XTRA_PROCPS_DEBUG #define be active.
And, we might as well add a warning when invalid items
are passed to 'GET' macros, just like we do for 'VAL'.

[ lastly, we added the missing opening parens/braces ]
[ to 2 'GET' macros in that xtra-procps-debug.h file ]
[ which went unnoticed until the qa folks caught up. ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-08-07 21:43:38 +10:00
Jim Warner
6cafe3abec library: expand VAL macros to include the context parm
This patch will set the stage for validating the types
referenced in the result union. For now, the parameter
representing that 'info' structure will remain unused.

[ and while we're at it, let us correct a faulty GET ]
[ macro in the diskstats header. that puppy missed a ]
[ parm which ain't so good if that guy is ever used! ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-08-07 21:40:48 +10:00
Jim Warner
c4d097c709 library: removed all the 'PROCPS_' enumerator prefixes
Many of our item enumerator identifiers are very long,
especially in that <VMSTAT> module. Additionally, they
all contain the exact same universal 'PROCPS_' prefix.

The origins for this are likely found in the desire to
avoid name clashes with other potential include files.
But with procps-ng newlib, we've probably gone way too
far. Did 'PROCPS_PIDS_TICS_SYSTEM' actually offer more
protection against clash than 'PIDS_TICS_SYSTEM' does?

I don't think so. Besides, no matter how big that name
becomes, one can never guarantee they'll never be some
clash. And, conversely, extremely short names will not
always create conflict. Of course, in either case when
some clash occurs, one can always #undef that problem.

Thus, this commit will eliminate that 'PROCPS_' prefix
making all of those enum identifiers a little shorter.
And, we'll still be well above some ridiculously short
(criminally short) names found in some common headers:

- - - - - - - - - - <term.h>
- 'tab', 'TTY', etc
- - - - - - - - - - - - - - - - <search.h>
- 'ENTER', ENTRY', 'FIND', etc

------------------------------------------------------
Finally, with this as a last of the wholesale changes,
we will have established the naming conventions below:

. only functions will begin with that 'procps_' prefix
. exposed structures begin with the module/header name
. item enumerators begin like structs, but capitalized
. other enumerators work exactly like item enumerators
. macros and constants begin just like the enumerators
------------------------------------------------------

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-07-26 20:49:00 +10:00
Jim Warner
82d5661603 library: standardize all the 'context' structure names
This patch attempts to standardize the naming of those
most important (declared not defined) context structs.

The present practice represents a hodge podge of names
only some of which reflect the source /proc file name.
And 2 of those file names embed a literal 'info' which
is likely the origin of that required parm identifier.

Now we'll append a universal '_info' to such structure
names, while including the names of those /proc pseudo
files where possible. In any case, that context struct
will *always* begin with the actual module/header file
name. And only the following two sound a little weird!

---------> 'meminfo_info' + 'slabinfo_info' <---------

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-07-26 20:47:34 +10:00
Jim Warner
8f1fb67a78 library: <MEMINFO> api, changed that 'get' return type
The following commit message is shared with 4 patches.
------------------------------------------------------

Under the newlib interface most of our 'get' functions
represent a bit of a compromise in that the actual raw
values are coerced into one (probably ok) return type.

That approach creates the possibility of truncation at
best, and wouldn't serve future needs should something
other than numeric data be added to the 'get' results.

This commit trades the current compromise for a return
value guaranteed to satisfy all future needs, namely a
pointer to a particular api's specific results struct.

The impact on existing programs is minimal, especially
when using a new supplied macro. Otherwise, native 'C'
syntax could be used, but may feel somewhat unnatural.

[ as an aside, this new approach allows us to delete ]
[ all 'getsfunc' table entries & the supporting code ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-06-21 20:58:09 +10:00
Jim Warner
4a0e974b7f library: more tweaks for code and/or comments, 3rd gen
Following is a summary of significant changes (if any)
to each of these now upgraded 3rd gen library modules.

<meminfo> ............................................
. eliminated duplicate decl of 'struct procps_meminfo'
. standardized/normalized results struct union members
. added 'std' & 'var' dividers in .c file, like <pids>
. how did i miss relocating all these friggin' #undefs
. cleanup 'get' return logic (remove a redundant 'if')

<pids> ...............................................
. repositioned the procps_pidsinfo structure in header
. removed the extra trailing comma from enum pids_item
. standardized/normalized results struct union members

<slabinfo> ...........................................
. corrected comment typo (jeeze, in an 'aligned' para)
. standardized/normalized results struct union members
. added 'std' & 'var' dividers in .c file, like <pids>
. removed an obsolete #undef from procps_slabinfo_sort
. cleanup 'get' return logic (remove a redundant 'if')

<stat> ...............................................
. how did i miss relocating all these friggin' #undefs
. corrected an initialization fencepost used with numa <=== see Craig, here's a bug fix
. removed the extra trailing comma from enum stat_item
. standardized/normalized results struct union members
. added 'std' & 'var' dividers in .c file, like <pids>
. strengthen those parm checks in procps_stat_get func
. cleanup 'get' return logic (remove a redundant 'if')

<vmstat> .............................................
. standardized/normalized results struct union members
. added 'std' & 'var' dividers in .c file, like <pids>
. cleanup 'get' return logic (remove a redundant 'if')

[ virtually all of these tweaks reflect the author's ]
[ continuing pursuit of an unreasonable goal -- that ]
[ of a 'perfect' (plus 'pretty') C language program! ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-06-17 21:44:29 +10:00
Jim Warner
876ec555c3 library: final tweaks to code and/or comments, 3rd gen
With the dust now settling on all those 3rd generation
upgrades, this patch tries to provide some consistency
among the separate modules involved. Someday we should
consider a 4th generation where all redundant code has
been removed and isolated in a new shared source file.

Following is a summary of significant changes (if any)
to each of these now upgraded 3rd gen library modules.

<meminfo> ............................................
. strictly formatting/comment changes, code unaffected

<pids> ...............................................
. replaced a local mkSTR macro with existing STRINGIFY
. added fetch narrative explaining duplicate addresses

<slabinfo> ...........................................
. rearranged some free logic for procps_slabinfo_unref
. added fetch narrative explaining duplicate addresses

<stat> ...............................................
. added #define ENFORCE_LOGICAL, just as in <slabinfo>
. replaced a local mkSTR macro with existing STRINGIFY
. alphabetized the function declarations in the header

<vmstat> .............................................
. made one coverity concession with read_vmstat_failed

[ several of these changes may reflect this author's ]
[ continuing pursuit of an unreasonable goal -- that ]
[ of a 'perfect' (plus 'pretty') C language program! ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-06-13 10:33:37 +10:00
Jim Warner
90753e2d5b library: remove the ull_int result type, <MEMINFO> api
Because of the vast quantities of virtual memory which
may be allocated, it initially seemed like a good idea
to provide for a widest possible range through the use
of a 'ull_int' result type. However, on second thought
the implementation was a bit flawed for these reasons:

. that underlying meminfo_data variable 'VmallocTotal'
is 'unsigned long' not a required 'unsigned long long'

. there wasn't a convenient way to value it since each
variable was set with a strtoul() call, not strtoull()

So this patch will standardize on the 'ul_int' results
type (and reduce the associated delta to 's_int' too).
For now, we'll rely on protections under a 64-bit arch
where a 'ull_int' & 'ul_int' yield identical capacity.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-05-12 21:15:01 +10:00
Jim Warner
407f1b71de library: improve/normalize an interface, <MEMINFO> api
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>
2016-05-12 07:51:10 +10:00
Craig Small
ccb6ae8de1 library: cleanup of library includes
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
2016-04-16 17:03:57 +10:00
Jim Warner
b8c688fb36 library: meminfo redesigned to use 'stack' vs. 'chain'
In addition to that text shown below the line which is
common to several commit messages, this patch contains
the following additional change without an API impact:

. The #include header files are ordered alphabetically
now, with all those <sys/??> types separately grouped.

------------------------------------------------------
. The former 'chains' have now become 'stacks' without
the 'next' pointer in each result struct. The pointers
initially seemed to offer some flexibility with memory
allocations and benefits for the library access logic.
However, user access was always via displacement and a
a statically allocated chain was cumbersome to define.

. An enumerator ending in '_noop' will no longer serve
as a fencepost delimiter. Rather, it has become a much
more important and flexible user oriented tool. Adding
one or more such 'items' in any items list passed into
the library becomes the means of extending the 'stack'
to also include user (not just library) data. Any such
data is guaranteed to never be altered by the library.

. Anticipating PID support, where many different types
must be represented in a result structure, we'll adopt
a common naming standard. And, while not every results
structure currently needs to reflect disparate types a
union will be employed so the same dot qualifier ('.')
can be used consistently when accessing all such data.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2015-07-23 22:31:24 +10:00
Jim Warner
aab537bc13 library: refactor meminfo providing dynamic allocation
An earlier approach to meminfo chaining, referenced in
the patch shown below, represents the first baby steps
toward the goal of some generalized approach with PIDs
processing. However, statically allocating a chain for
each task or thread is totally impractical. And, while
a single chain could serve all PIDs, that would mean a
separate call to our library for each running process.

This commit is intended as the next evolutionary step,
dynamically allocating some 'result' chains to contain
as many or as few 'items' as a caller wishes. In other
words, holding only those 'items' of current interest.

This is the kind of service useful for both top and ps
programs if we finally get around to /proc/<PID> data.

Reference(s):
commit c3fd7473c5

Signed-off-by: Jim Warner <james.warner@comcast.net>
2015-07-14 22:32:41 +10:00
Jim Warner
faf6d4dc93 library: the uref functions were insufficiently robust
The earlier attempt at protecting these functions from
already freed memory worked just fine until the memory
was, in fact, reused by the OS. At that point, the ref
count would most likely fail an existing a test for 0.

So this commit will take control of the 'info' pointer
and force it to NULL when a reference count reaches 0.

Plus, since it makes little sense returning an address
that a caller already has, henceforth we will return a
reference count out of the 'ref' and 'unref functions.

Reference(s):
commit 74beff80ff

Signed-off-by: Jim Warner <james.warner@comcast.net>
2015-07-01 21:30:17 +10:00
Jim Warner
a05084f381 library: add chaining provisions to meminfo and vmstat
If a caller chooses to reduce the overhead of repeated
function calls, this commit provides for acquiring all
the desired information in just a single library call.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2015-06-29 21:29:29 +10:00
Jim Warner
500a901475 library: tweak formatting style for meminfo and vmstat
This patch mostly just eliminates darn tab characters.

Plus the library function declarations and definitions
have been standardized. Most visibly, the input params
now have all been indented on their own separate line.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2015-06-29 21:29:19 +10:00
Craig Small
05efbebb66 library: Fix up stat API
Adjusted vmstat to use the new API for memory and CPU statistics
2015-06-26 22:37:28 +10:00
Craig Small
ca4a09c432 library: memory and vmstat API changes
Created new set of functions for meminfo related calls. Liked the
format of that better so changed vmstat around so the look similar.
Missed the makefile change for uptime so added it in now.
2015-06-26 22:37:28 +10:00
Craig Small
a20e88e4e7 library: Add procps_meminfo_* functions
New set of functions that read the /proc/meminfo file. Still needs
work.
2015-06-26 22:37:28 +10:00