Commit Graph

14 Commits

Author SHA1 Message Date
Jim Warner
8f1fb67a78 library: <MEMINFO> api, changed that 'get' return type
The following commit message is shared with 4 patches.
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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