Commit Graph

63 Commits

Author SHA1 Message Date
Jim Warner
63e828fe88 library: minor tweaks of program logic and/or comments
This commit just corrects the oversight wherein 'item'
was being employed when 'these' was actually intended.

Also, it trades some 'item' use for a more descriptive
input parameter which henceforth is known as a 'dest'.

And, there was one leftover 'next' pointer eliminated.

Finally, some logic was made a tad less dependent upon
enumerator names and a few comments were also updated.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2015-07-28 21:51:00 +10:00
Jim Warner
ae4b686745 library: eliminate extra stack header space provisions
With the new perspective on potential uses of a 'noop'
enumerator (or whatever we decide to call it) there is
no longer a need to provide for any extra 'user' space
in the stack header structures used by slab & meminfo.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2015-07-23 22:31:50 +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
74cb6afcc9 library: tweak new interface code and improve comments
With a little help from smatch, this commit eliminates
some inappropriate code. Also some programmer comments
were (barely) improved (i hope) in some small measure.

Reference(s):
smatch: 406 procps_meminfo_chain_fill() warn: variable dereferenced before check 'chain' (see line 403)

Signed-off-by: Jim Warner <james.warner@comcast.net>
2015-07-15 21:25:09 +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
74beff80ff library: make reads & unref logic a little more robust
Since we are not using a higher level standard C fopen
all of the read requests were made signal sensitive as
that can result in a 'temporarily' failed i/o request.

Also, protection against some user calling the 'unref'
function on already free memory has been incorporated.
This will protect us from some nasty 'Abort' surprise.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2015-06-29 21:30:48 +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
7a98cab187 library: add missing meminfo logic, improve efficiency
This patch fills in some missing fields which have top
dependencies. Additionally, I've tried to mirror those
calculations Jaromir added for release 3.3.10. The one
calculation that remains missing is 'available' memory
for some kernels. For this API, we'll use a fall-back.

Lastly the lxc safeguards which were recently added to
the old procps library were incorporated here as well.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2015-06-29 21:29:24 +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