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6 Commits

Author SHA1 Message Date
Jim Warner
e41b40e6b0 library: <SLABINFO> api, change 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
6a70466ae5 library: overcome effect of copy/paste, <SLABINFO> api
Needless to say, when one copies and then pastes, it's
always better when those results are refined somewhat.

The qsort callback declarations used the wrong results
type and 2 of their 3 input parameters were wrong too.

So this patch will fix that & generalize declarations.

[ plus add comment guidance about noop & extra enums ]
[ & provide for 'noop' sorting, as is done in <PIDS> ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-06-11 11:50:37 +10:00
Jim Warner
5d5a52a380 library: normalize/standardize the i/f, <SLABINFO> api
Before this major redesign, the slabs interface likely
was our messiest 2nd generation attempt at opaqueness.
Beyond the standard 'new', 'ref' & 'unref', there were
a total of 12 exported functions. Now, there are four.

The 1st step was to remove several of those functions.
These were quick to go since they were not used (yet):
. procps_slabnode_count
. procps_slabnode_getname
. procps_slabnode_getstack

Then, the following were internalized so users needn't
be burdened with implementation details in the future:
. procps_slabinfo_read (renamed: read_slabinfo_failed)
. procps_slabnode_stacks_alloc (renamed: stacks_alloc)

Still others evolved into the minimal interface we had
strived for in the other upgraded 3rd generation APIs:
. procps_slabnode_get -----------> procps_slabinfo_get
. separate stack_alloc/fill --> procps_slabinfo_select
. separate stacks_alloc/fill ---> procps_slabinfo_reap
. procps_slabnode_stacks_sort --> procps_slabinfo_sort

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Beyond those reductions, the major modifications were:

. This API tries to be as forgiving as possible and as
such won't throw errors when a caller request makes no
sense. For example, if a 'get' or 'select' requested a
SLABNODE item (with no current means to id that node),
results will be zero. By the same token, should 'reap'
include a global SLABS item (meaning those values will
be duplicated in *every* node stack) it'll be allowed.

. If the above behavior is undesired, a new #define of
ENFORCE_LOGICAL can be used to restrict certain items.

. Permission problems will now be caught at 'new' time
thanks to a priming 'read' call. That read also serves
to make DELTA values potentially useful at 1st access.

. Separate slab/slabnode enumerators were consolidated
into one, simplifying validation & the results struct.

. Several internal parameter checks were relaxed since
they were already checked by the caller. Besides if we
cannot trust our own code we might as well hang it up.

. That sort provision was made more efficient and will
offer the ascending choice, in addition to descending.

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Lastly, some additional thoughts regarding the future:

. It would not be difficult to expand 'select' to also
accept a nodeid, or to clone it as 'select_node'. And,
should the same be extended to 'get', a results struct
could be returned instead of signed long accommodating
the extra data type(s) like a node name (string data).

. The 'get' function is not currently affected by that
 define ENFORCE_LOGICAL. However, at some future point
perhaps -EINVAL would be more appropriate than a zero.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-06-09 20:51:06 +10:00
Jim Warner
5be4167782 library: rename the 'slab' sources as 'slabinfo' files
Where possible, libprocps files convey the name of the
actual source pseudo file under the '/proc' directory.

This patch brings slab into line with such a standard.

Signed-off-by: Jim Warner <james.warner@comcast.net>
2016-06-09 20:51:06 +10:00