The commit referenced below addressed (some) anomalies
surrounding 'strv' pointers. However, there remained a
couple quirks involving a potential NULL return value.
Any NULL values returned from the old library readproc
guys would cause no real harm for newlib. But they did
produce the misleading "[ duplicate ENUM_ID ]" result.
The following all represent potential NULL results and
suggest shortcomings in testing of that earlier patch.
. kernel threads do not have cgroup, cmdline & environ
. even if present environ could require root to access
So, this patch reverts a portion of the earlier commit
and ensures when some vectored string is not available
a traditional dash ('-') is the 'strv' returned value.
[ and we'll also correct one typo in the header file ]
Reference(s):
. eliminated a final potential NULL, <PIDS> api
commit 09503dc597
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit is intended as a refinement of the patches
mentioned below, where origins/sources of newlib items
were added to the header files for user documentation.
However, if those additions are to be truly effective,
along with kernel documentation (where available), the
following prerequisites must also have been satisfied:
. our identifiers closely align with linux field names
. our derived items are documented or self-documenting
Satisfying those prerequisites prompted this patch and
for these changes, kernel sources were emphasized over
available documentation (shame on me, it should always
have been so). And, while some 'new' fields were found
to be conditional, they were included unconditionally.
These changes appear more extensive than they actually
need be since I have attempted to enforce some spacing
conventions. So, I've summarize the significant things
in the sections that follow. For a proper perspective,
use: 'git diff --ignore-space-change' (good as alias).
___________________________________________ <PIDS> api
This api is unique in that there exists many different
file/directory origins subordinate to /proc/<pid>. And
our item identifiers are sometimes coerced so as to be
able to group related or similar enumerators together.
So, users needed more help relating our identifiers to
an actual documented field. Thus, we will now also add
the field names as with 'stat: delayacct_blkio_ticks'.
Each item ending with a '_C' now consistently includes
both the parent's count/time plus waited for children.
That 'RTPRIO' guy was renamed/relocated as PRIORITY_RT
since its original name is an implementation artifact.
___________________________________________ <STAT> api
The only api change was to correct a typo ('dervied').
_________________________________________ <VMSTAT> api
Even ignoring white space, this interface received the
largest number of changes. Mostly, this was because of
deficiencies in the proc(5) documentation. Recall that
this documentation already sorely lacks any substance.
Usually, just kernel releases are noted, not contents.
When compared to kernel source, that proc(5) contained
many non-existent fields and also omitted many others.
________________________________________ <MEMINFO> api
Sadly, with this api many of the changes were simply a
correction of some earlier 'human error' where several
fields where hashed then tracked but never represented
with an item enumerator in this meminfo.h header file.
_______________________________________ <SLABINFO> api
The 'SLABS' (summary) & 'SLABNODE' items were reversed
since the former are derived from the separate caches.
More significantly, those 'SLABNODE' guys were renamed
to 'SLAB' since they concern individual caches and the
concept of 'nodes' is really an implementation detail.
Also, several enumerators were changed to more closely
agree with official slabinfo(5) documentation referred
to in what we're treating as a base document: proc(5).
Lastly, while those 'SLABS' items are solely a product
of our library and not represented in slabinfo(5), the
names attempt to parallel those found as 'SLAB' items.
______________________________________ <DISKSTATS> api
One enumeration identifier was changed so as to better
reflect its relationship to that actual documentation:
'Documentation/iostats.txt', as referenced in proc(5).
Reference(s):
. 12/2018, item origins added (and commit msg history)
commit 96d59cbf46
. 01/2019, <stat> origins tweaked
commit 201e816b26
Signed-off-by: Jim Warner <james.warner@comcast.net>
A lack of documentation seems to be the major obstacle
to releasing this new library. So, in an effort to get
the ball rolling again, this patch adds the origins of
each item as a comment to six of the new header files.
However, before reviewing how such changes may benefit
that documentation objective, it seemed appropriate to
first reflect on newlib's background & current status.
___________________________________________ BACKGROUND
Discussions about and work on a new library began back
in July 2012 but quickly died. After a lull of 2 years
those discussions were resumed in August 2014 but soon
died also (and no code survived the gitorious demise).
With those early discussions, the recommended approach
was to encapsulate all of the libprocps data offerings
in individual functions. When it came to extensibility
it was suggested we should rely on symbols versioning.
Unfortunately that approach would have made for a huge
Application Programming Interface virtually impossible
to master or even document. And, runtime call overhead
would have been substantial for ps and especially top.
So, an alternative design was sought but there were no
new suggestions/contributions via freelists or gitlab.
Thus, in spite of a lack of library design experience,
the procps-ng team (Craig & Jim) set out to develop an
alternative API, more concise and with lower overhead.
Reference(s):
. 07/01/2012, begin library design discussion
https://www.freelists.org/post/procps/Old-library-calls
. 08/12/2014, revival of library design discussion
https://www.freelists.org/post/procps/libprocs-redesign
_____________________________________ DESIGN EVOLUTION
Our newlib branch first appeared on June 14, 2015. And
our current API actually represents the 4th generation
during the past 3 years of evolution. First, there was
a basic 'new', 'get' and 'unref' approach, using enums
to minimize the proliferation of 'get' function calls.
Then, in anticipation of other programs like ps, where
multiple fields times multiple processes would greatly
increase the number of 'get' function calls, a concept
of 'chains' was introduced. This became generation #2.
Such 'chains' proved unnecessarily complex so 'stacks'
replaced them. This was considered the 3rd generation,
but too many implementation details were still exposed
requiring those users to 'alloc', 'read', 'fill', etc.
Finally, a 4th generation emerged representing several
refinements to standardize and minimize those exported
functions, thus hiding all implementation details from
the users. Lastly, handling of 'errno' was normalized.
Reference(s):
. 06/14/2015, revival of new API discussion
https://www.freelists.org/post/procps/The-library-API-again
. 06/24/2015, birth of the newlib branch
https://www.freelists.org/post/procps/new-library
. 06/29/2015, 2nd generation introduced 'chains'
https://www.freelists.org/post/procps/new-library,8
. 07/22/2015, 3rd generation introduced 'stacks'
https://www.freelists.org/post/procps/newlib-stacks-vs-chains
. 06/18/2016, 4th generation refinements begin
https://www.freelists.org/post/procps/newlib-generation-35
. 11/10/2017, 4th generation standardized 'errno'
https://www.freelists.org/post/procps/some-more-master-newlib-stuff
_______________________________________ CURRENT DESIGN
Central to this new design is a simple 'result' struct
reflecting an item plus its value (thanks to a union).
As a user option, these item structures can be grouped
into 'stacks', yielding many results with just 1 call.
Such a 'stack' can be seen as a variable length record
whose content/order is determined solely by the users.
Within that 'result' structure, the union has standard
C language types so there is never a doubt how a value
should be used in a printf statement. Given that linux
requires a least a 32-bit platform the only difference
in capacity surrounds 'long' integers. And, where such
types might be used, the 32-bit maximums are adequate.
The items themselves are simply enumerators defined in
the respective header files. A user can name any items
of interest then the library magically provides result
structure(s). The approach was proven to be extensible
without breaking the ABI (in commit referenced below).
The 6 major APIs each provide for the following calls:
. 'new' ---------> always required as the first call .
. 'ref' -------------------------> strictly optional .
. 'unref' --------> optional, if ill-behaved program .
. 'get' --------------------> retrieve a single item .
. 'select' ----------------> retrieve multiple items .
And the 'get' and 'select' functions provide for delta
results representing the difference between successive
get/select calls (or a 'new' then 'get/select' call).
For the <diskstats>, <pids>, <slabinfo> & <stat> APIs,
where results are unpredictable, a 'reap' function can
return multiple result structures for multiple stacks.
The <pids> API differs from others in that those items
of interest must be provided at 'new' or 'reset' time,
a function unique to this API. And the <pids> 'select'
function requires PIDs or UIDs which are to be fetched
which then operates as a subset of 'reap'. Lastly, the
'get' function is an iterator for successive PIDs/TIDs
returning items previously identified via 'new/reset'.
To provide assistance to users during development, the
special header 'proc/xtra-procps-debug.h' is available
to check type usage against library expectations. That
check is activated by including this header explicitly
or via build using: ./configure '-DXTRA_PROCPS_DEBUG'.
Reference(s):
. 08/05/2016, type validation introduced
https://www.freelists.org/post/procps/newlib-types-validation
commit e3270d463d
. 08/11/2016, extensibility while preserving ABI example
https://www.freelists.org/post/procps/new-meminfo-fields
commit 09e1886c9e
_________________________ INITIAL DOCUMENTATION EFFORT
The initial attempt, referenced below, dealt primarily
with the <pids> interface. Separate man pages for each
exported function were created. Plus there was another
document describing the items, among other miscellany.
Adopting such an approach encounters several problems:
1. In order to use these man pages, users are required
to already know how to use the library. Or alternately
one could randomly search each of them while trying to
ascertain which function call satisfies their need and
what exactly was the proper compliment/order required.
2. While we can explain what all of those <pids> items
represent, that certainly isn't true for all the APIs.
See the gaps in kernel documentation for <meminfo> and
complete lack of documentation with that <vmstat> API.
3. Our documentation effort should take pains to avoid
unnecessary implementation details. Here's an example:
. "The pointer to info will have memory"
. "allocated and a structure created."
Alternatively, the following conveys user requirements
while not offering any internal implementation detail:
. "You must provide the address of a NULL"
. "info structure pointer."
Reference(s):
. 01/04/2017, initial documentation offering
https://www.freelists.org/post/procps/Using-reap-and-get
commit 2598e9f2ce
___________________ RECOMMENDED DOCUMENTATION APPROACH
I recommend that the newlib documentation consist of 3
man pages only. The first would cover the 5 major APIs
and their common functions. The second would deal with
the <pids> API exclusively, explaining how it differs.
Any remaining exported libproc functions which are yet
to be included could be represented in a 3rd document.
For these new documents the following are are assumed:
1. Since we will not be able to document all items, we
shouldn't try to document any items. We should instead
rely on proc(5) or Documentation/filesystems/proc.txt.
2. Program development often involves referencing some
header file(s). So, make that an absolute requirement.
3. With the addition of item origins, represented with
this commit, and considering that 'types' were already
present, the header file might be all some users need.
4. And who knows, when a user of our libproc complains
about gaps in their documentation, it might prompt the
kernel folks to correct those long standing omissions.
To summarize, I suggest that we replace that libproc.3
document with a more general one explaining the basics
of accessing this new library and the common calls for
most of the major interfaces. We can then create a new
document (libproc-pids.3?), which explains differences
in using the <PIDS> application programming interface.
A final document (libproc-misc.3?) covers what's left.
Signed-off-by: Jim Warner <james.warner@comcast.net>
This change is being made in anticipation of adding the
source origin of each item to the <pids.h> header file.
Signed-off-by: Jim Warner <james.warner@comcast.net>
If we ever were to eliminate the procps.h header file,
as discussed in the thread referenced below, then that
would impair the current XTRA_PROCPS_DEBUG provisions.
The only remaining way to verify result types would be
to explicitly include that <proc/xtra-procps-debug.h>.
So, this commit will once again enable the ./configure
provision for defining the -DXTRA_PROCPS_DEBUG option.
Reference(s):
https://www.freelists.org/post/procps/newlib-Qualys-patches,6
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch is the first of three implementing a newlib
branch version of that Jan Rybar master merge request.
With this series we'll ultimately extend 'EXE' support
to both ps and top (plus, everyone else who wants it).
Reference(s):
. master branch merge request
https://gitlab.com/procps-ng/procps/merge_requests/66
Signed-off-by: Jim Warner <james.warner@comcast.net>
When 'newlib' was introduced, in the commit referenced
below, the use of that glibc '__BEGIN_DECLS' macro was
standardized. However, as issue #88 revealed, this may
result in a fatal build error with other environments.
So, this patch just trades that macro for the standard
'#ifdef __cplusplus' conventions (thus avoiding use of
all those '#include <features.h>' directives as well).
Reference(s):
. newlib introduced
commit a410e236ab
. procps-ng-3.3.13 issue
https://gitlab.com/procps-ng/procps/issues/88
. some additional discussion
https://www.freelists.org/post/procps/PATCH-Replace-glibcspecific-macros-in-procnumah,1
. musl wiki (see: sys/cdefs.h error messages)
https://wiki.musl-libc.org/faq.html
Signed-off-by: Jim Warner <james.warner@comcast.net>
With the documentation update in the commit referenced
below, we should also account for such threads as they
will already be represented in the task/thread totals.
[ and do it in a way that might avoid future changes ]
Reference(s):
commit 91df65b9e7
Signed-off-by: Jim Warner <james.warner@comcast.net>
In response to that suggestion referenced below, these
changes allow display of task/thread level NUMA nodes.
Currently, only the 'top' program offers any NUMA type
support and it is limited to the Summary Area display.
With this commit both the 'top' and 'ps' programs will
be able to display NUMA nodes associated with threads.
Reference(s):
https://gitlab.com/procps-ng/procps/issues/58
Signed-off-by: Jim Warner <james.warner@comcast.net>
Removing the Item_table 'stat' oldflags for WCHAN_ADDR
was wrong since that 'stat' field is not a constant 0.
Rather, it could assume these 3 values: -1, 0, and +1.
I have not been able to pin down a '-1' result, but it
probably means some sort of permission error (-EPERM).
The '1' or '0' values were supposed to distinguish the
tasks that were or were not blocked (whether there was
a wchan address). However, in practice there is little
correlation between those values and availability of a
kernel symbol in /proc/$$/wchan (perhaps due to race).
Anyway, the real point is that a 'stat' wchan does not
now intentionally contain an address. Thus, outputting
'ffffff', '-' or '1' in programs like ps is senseless.
So this patch just eliminates PIDS_WCHAN_ADDR from our
item enumerators leaving only the PIDS_WCHAN_NAME guy.
Now the new library can't be blamed for bad addresses!
Reference(s):
. removed Item_table 'oldflags'
commit c4aa6c0ab4
. linux removal of wchan addresses
commit b2f73922d119686323f14fbbe46587f863852328
Signed-off-by: Jim Warner <james.warner@comcast.net>
It seems inappropriate to blindly include fields known
to always be zero in our brand new library. Therefore,
this patch removes support for three such enumerators.
[ that stat 'it_real_value' (PIDS_ALARM) field could ]
[ have been made obsolete before a linux 2.6 release ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit just contains some tweaks to comments plus
a few adjustments to whitespace for alignment purposes
and a normalization of the header inclusion #define's.
[ plus a spelling error in one header file was fixed ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
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>
This commit attempts to minimize the variety of types
currently used. Plus, the following were also changed:
. the MEM fields were switched to parallel the VM guys
. PIDS_MEM_VIRT -> PIDS_MEM_VIRT_PGS
. PIDS_MEM_VIRT_KIB -> PIDS_MEM_VIRT
. made NICE 's_int' so that it then parallels PRIORITY
. change RTPRIO & SCHED_CLASS from 'ul_int' to 's_int'
. removed Item_table 'oldflags' for an obsoleted field
. PIDS_WCHAN_ADDR
. added calculations like TICS_ALL_C for the following
. PIDS_TICS_USER_C
. PIDS_TICS_SYSTEM_C
. these three new 'TICS' fields have been incorporated
. PIDS_TICS_BLKIO - jiffies spent in block i/o
. PIDS_TICS_GUEST - jiffies spent as a guest
. PIDS_TICS_GUEST_C - as above, includes dead children
. that PIDS_TICS_DELTA was renamed PIDS_TICS_ALL_DELTA
( so it did not hide between TICS_BLKIO & TICS_GUEST )
( and to make clearer what's included: utime + stime )
. eliminated 'sl_int' entirely from that result struct
[ often, the <pids> module changes necessitated that ]
[ readproc header and source files had to change too ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
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>
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>
With all our 3rd generation interfaces, we're now well
positioned to preserve binary compatibility should new
fields be added to any public structure (assuming that
the 'result' union already contains its largest type).
This remains true even for the <pids> interface, which
unlike the others, has one structure embedded within a
separate struct rather than declaring a pointer to it.
The counts struct was positioned after the stacks ptrs
array so as to preserve that ABI if ever new ints were
added. Logically, however, the counts (especially that
total) should precede the stacks array if we wished to
properly place a horse (total) before a cart (stacks).
So to enable relocating those counts we will no longer
embed that structure, but provide a pointer to it. And
this will make accessing syntax feel more natural too.
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch represents the following minor adjustments:
. old PROCTAB used with select & reap more descriptive
. reformatted PROCPS_PIDS_VAL macro like other 3rd gen
Signed-off-by: Jim Warner <james.warner@comcast.net>
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>
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>
This commit simply tries to keep naming plus formating
conventions on a par with the continuing climb up that
learning curve. These changes were suggested following
<slabinfo> sources upgrade from 2nd to 3rd generation.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Rather than adopt an approach offered below, involving
changing all enumerator names to convey types, perhaps
this much more modest change is a worthwhile 1st step.
By just changing the comments to 'right justification'
it dramatically improves readability, at least it does
to my eye. Perhaps such an approach can postpone that
massive alternative effort for the foreseeable future.
Reference(s):
http://www.freelists.org/post/procps/newlib-drip-drip,4
Signed-off-by: Jim Warner <james.warner@comcast.net>
This is just beginning an effort to minimize/normalize
the sheer variety of results types in use for our API.
In taking these first baby steps, a few anomalies were
found. There'll no doubt be many more yet to discover.
. the _FLT_ (fault) fields were already signed long in
the proc_t (even though their sscanf format used %lu).
. although strtoul will alway return an unsigned long,
all of the _VM_ fields were made signed long just like
other memory fields (& signed sorts more efficiently).
Reference(s):
http://www.freelists.org/post/procps/newlib-drip-drip,4
Signed-off-by: Jim Warner <james.warner@comcast.net>
This represents a rather major interface redesign. The
following highlights most of the changes/enhancements.
. The 'read' interface (employed by pgrep & pidof) saw
the biggest change. The 'open', 'next' and 'shut' guys
all went bye-bye, replaced by a single 'get' function.
. The items specified at 'new' time no longer serve as
the maximum. In fact, items & numitems are now treated
as optional, should callers prefer to wait until later
when the 'reset' function would then become mandatory.
. Even at 'reset' time, the stacks are not tied to any
sort of maximum. They will grow dynamically as needed.
. The order of some parameters was changed to parallel
that found in our other APIs. Specifically, when items
& numitems are needed they're specified in that order.
. A user will no longer be prevented from concurrently
employing any accessor functions. In other words, that
'get' (old 'read') won't preclude 'reap' and 'select'.
. A duplicate enumerator was found dealing with locked
resident pages. So, the name VM_LOCK was eliminated in
favor of VM_RSS_LOCKED, which is way more descriptive.
. The struct address returned to callers following any
reap() or select() is now more sharable as pids_fetch.
. Some input parameter names were changed to make them
more descriptive of the intended purpose/requirements.
------------------------------------------------------
Internally, there were numerous implementation changes
made that did not directly impact any potential users.
. That #define FPRINT_STACKS was eliminated along with
the associated supporting function and its invocation.
. Addresses returned following 'reap' or 'select' will
now be NULL delimited, so one has the option of stacks
access via the total count or this new NULL fencepost.
. Input params were simplified and generalized in both
oldproc_open() & close() to enable more than 1 PROCTAB
to be open simultaneously, which was required for get.
. The PROCPS_PIDS_logical_end enum was relocated after
the Item_table making the need to keep it synchronized
more apparent (if the table expands it's right there).
. The 'Public function' section of the source file was
subdivided into 1) the three basic required functions;
and 2) functions that can sometimes vary between APIs.
Signed-off-by: Jim Warner <james.warner@comcast.net>
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>
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
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>
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>
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 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>
Work on converting ps has revealed the desirability of
trading a void pointer for that ul_int type. There was
much arithmetic employed against such values and casts
would otherwise have been required. Even pmap needed a
cast on occasions when comparing an internal variable.
Besides, there is much to be said for reducing demands
on (and the complexity of) the result structure union.
[ we choose ul_int over ull_int since that former is ]
[ the exact same size and capacity as a void pointer ]
[ regardless of whether compiled as 32-bit or 64-bit ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
OK, ok, this was kind of a huge omission. So please do
not select the TTY field for display in top quite yet,
at least until a next patch has been pushed to GitLab.
And to produce a correct sort order for this new field
the GNU 'strverscmp' routine was a necessary addition.
Signed-off-by: Jim Warner <james.warner@comcast.net>
The presence of that PROCPS_PIDS_noop may yet see some
use in the future with its 'no alter' library promise.
However, when top used that item to reflect the forest
view nesting level, the unchanging nature of that item
became more of an inconvenience than benefit. For each
refresh top was forced to loop through all the stacks,
resetting that PROCPS_PIDS_noop result struct to zero.
So this commit will now offer users a choice between a
new re-initialized item (PROCPS_PIDS_extra) & the noop
invariant. Since the library already resets all those
result structures, top will now utilize it at no cost.
Signed-off-by: Jim Warner <james.warner@comcast.net>
As an experiment a helper macro used to extract values
from a result stack has been added to the header file.
Don't force callers to reinvent that particular wheel.
Signed-off-by: Jim Warner <james.warner@comcast.net>
After experimenting with an adaptation of pidof to the
new pids interface, it became apparent that vectorized
versions of those command lines would be necessary. So
this commit adds that option and the strv result type.
And since the stage had been set, a vectorized version
of PROCPS_PIDS_ENVIRON & PROCPS_PIDS_CGROUP was added.
Lastly, any use of 'const' in the result structure was
removed so callers need not be bothered with casts and
compiler warnings. Hopefully, they'll respect a stack.
Signed-off-by: Jim Warner <james.warner@comcast.net>
To ease the transition to the new interface, for other
than that top program, individual read provisions have
been added to the <proc/pids.h> API. This represents a
refinement of a position stated in a post noted below.
Reference(s):
http://www.freelists.org/post/procps/newlib-ps-fix
Signed-off-by: Jim Warner <james.warner@comcast.net>
. traded a complex misaligned memory allocation scheme
in the make_hist function for a simple aligned scheme.
plus memory allocation increases are globally defined.
. changed 1 parameter for procps_pids_stacks_sort() to
better reflect the 'array of pointers', not an address
of a pointer as is used with guys such as 'new/unref'.
. the pids_reap struct was changed slightly to make it
more reflective of it's actual implementation details.
. the Item_table member .mustfree is now .needfree and
that .makehist was now made .needhist for consistency.
. reduced the number of separate 'return NULL;' source
statements in that primary procps_pids_reap() routine.
. ensured consistent reference to sizeof(void *) & not
occasional reference to sizeof(void*) without a space.
. rather than enable/disable validate_stacks via a #if
in the function body, it is now handled via a #define.
. some comments in the procps_pids_reset function were
adjusted to reflect this current implementation. shown
originally, they reflected an aborted attempt to avoid
a testing aberration not fully understood at the time.
. added a summary of the memory overhead cost of HST_t
processing to that UNREF_RPTHASH output at unref time.
. a 'PIDs at max depth:' portion of that UNREF_RPTHASH
enabled #define is now published only when the maximum
depth of hash table entry chains exceed depths of one.
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit is the culmination of efforts to modernize
the library api. It should be treated as a first blush
attempt, especially since I have absolutely no library
design experience. But I did have a very strong desire
to lessen the new library's impact on the top program.
Under this new api, a 'stack' is the equivalent of the
old proc_t. It can be seen as a variable length record
whose contents & order is under complete user control.
That initial stack/record configuration is established
at procps_pids_new() time and will probably serve most
program needs. But, a dynamic & demanding program like
top will later change a stack via procps_pids_reset().
For programs like top & ps, procps_pids_reap() will be
the function that will retrieve all tasks and threads.
Any program that needs to filter / select only certain
processes or users have available other functions that
can be used: procps_pids_stacks_alloc, fill & dealloc.
This implementation attempts to maximize that existing
proven libprocps code base. As we gain more experience
such actual code can be migrated into the pids.c file.
Signed-off-by: Jim Warner <james.warner@comcast.net>
