This just updates the copyright dates in the documents
where I was already represented. Others are unchanged.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Our new library's now well protected against potential
problems which arise when a multi-threaded application
opens more than one context within the same API at the
same time. However, with a single-threaded application
designed along those same lines, some problems remain.
So, to avoid potential corruption of some data (which
was classified as local 'static __thread') from those
single-threaded designs, we'll move several variables
to the info structure itself and remove the '__thread'
qualifier. Now they're protected against both designs.
[ we'll not be protected against some multi-threaded ]
[ application that shares a single context yet calls ]
[ that interface from separate threads. this is just ]
[ bad application design & no different than sharing ]
[ other modifiable global data between such threads! ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
Even though we we had to abandon the master branch top
multi-thread effort and even though the newlib version
of a multi-threaded top provides no real benefit, that
whole exercise was not wasted. Rather, it has revealed
some deficiencies in our library which this addresses.
If two or more threads in the same address space tried
to access the same api simultaneously, there is a good
chance some function-local static variables will yield
some of those renowned unpredictable results. So, this
patch protects them with the '__thread' storage class.
Reference(s):
https://www.freelists.org/post/procps/a-few-more-patches,7
Signed-off-by: Jim Warner <james.warner@comcast.net>
This small change was a result of some experimentation
trading our current 'hsearch' hash scheme for 'gperf'.
I discovered that when the ':' character was a part of
each 'gperf' key, that generated search logic was more
complicated and thus slower. But without a ':', it was
a little cleaner/leaner and therefore slightly faster.
Assuming that the same trailing ':' *might* affect the
current 'hsearch' logic, to be safe we will remove it.
[ while the 'gperf' version will slightly outperform ]
[ an 'hsearch', too many ugly implementation details ]
[ were exposed which complicates future maintenance. ]
[ thus, we'll retain our current 'hsearch' approach. ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch will condense some logic in those functions
associated with the file input operations. The changes
will not, for the most part, alter any generated code.
More significantly (though not very) was the change to
two 'strtoul' calls. Since the returned 'endptr' value
isn't exploited, when that parm is set to NULL, we can
save one instruction on each side of such calls (wow).
Signed-off-by: Jim Warner <james.warner@comcast.net>
In addition to copyright date, the initial descriptive
line was changed from a generic statement to one which
reflects the specific portion of the proc/ filesystem.
[ such descriptions alternate between 'declarations' ]
[ (h files) & corresponding 'definitions' (c files). ]
Also, a few missing copyright attributions were added.
Signed-off-by: Jim Warner <james.warner@comcast.net>
There's a huge toe-stubber awaiting future maintenance
as reflected in that commit below which deals with the
addition of new enumerators to the Item_table. Namely,
whenever the table is grown, one must remember to also
change that existing 'logical_end' enumerator's value.
Well, not anymore! Since that MAXTABLE macro was added
to the procps-private.h header we can now also exploit
it so a 'logical_end' automatically tracks table size.
This change also renders some code associated with the
ITEMTABLE_DEBUG #define unnecessary. So it's gone too.
Reference(s):
. 08/2016, add new enumerators
commit 09e1886c9e
. 08/2020, added MAXTABLE macro
commit c865b06c30
. 08/2020, introduced ITEMTABLE_DEBUG
commit 92d0297e1e
Signed-off-by: Jim Warner <james.warner@comcast.net>
The recent work on updating the <meminfo> and <vmstat>
modules with some newly added linux fields reminded me
(again) of a need for some mechanism guaranteeing that
a header file agrees with the source file assumptions.
Sadly, in the past, if a table entry was omitted or if
the table and header are ordered differently, then the
library would silently return the wrong results values
or even potentially experience a SIGSEGV abnormal end.
This patch offers a much needed development assist for
ensuring that Item_table entries are synchronized with
header file enumerators in terms of number plus order.
It's intended solely for our use as libprocps evolves.
Now, by activating ITEMTABLE_DEBUG, either directly or
via ./configure CFLAGS='-DITEMTABLE_DEBUG', the number
and order will be verified. It is envisioned that this
feature will be used at least once prior to a release.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Since last visited, there have been several new fields
added and one field deleted in the /proc/meminfo file.
[ references shown below represent linux git commits ]
Reference(s):
. 4/2020, added 'ShadowCallStack'
commit 628d06a48f57c36abdc2a024930212e654a501b7
. 9/2019, added 'FileHugePages' & 'FilePmdMapped'
commit 60fbf0ab5da1c360e02b7f7d882bf1c0d8f7e32a
. 9/2019, removed 'Quicklists'
commit 13224794cb0832caa403ad583d8605202cabc6bc
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch just trades the 'typestr' for the much more
meaningful 'valid range' when a relative enum has been
deemed invalid under that XTRA_PROCPS_DEBUG provision.
[ and we'll also make one comment a bit more generic ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
The meminfo & vmstat file read buffers are now defined
through symbolic constants next to the symbolic names.
[ recent attention to the /proc/stat buffer size led ]
[ to this (hopefully) better approach to definitions ]
Reference(s):
commit 81f4a6acdf
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch just standardizes/normalizes the whitespace
employed within a couple of nearly identical #defines.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Some parts of our newlib implementation are the result
of functions which have been propagated from module to
module. In particular, those 'cleanup_stacks' routines
are all similar & likely originated in the <pids> api.
In that interface there was a need to free dynamically
acquired memory before the result structure was reused
to satisfy subsequent 'get', 'select' or 'reap' calls.
This, in turn, led to a concept of 'dirty' stacks with
the need to call one of two 'cleanup_stack' functions.
None of the remaining interfaces deal with such memory
yet they each had their own 'cleanup_stack' functions.
Those functions were responsible for resetting each of
the result unions to zero, excluding any 'noop' items.
The bottom line is that for all interfaces, repetitive
calls would require iterating through the stack(s) two
separate times: once to 'cleanup' another to 'assign'.
With this commit we will reduce iterations to just the
'assign' routine. A reset to zero will be accomplished
in the 'extra' item set routine (which is the only one
actually requiring any reset). All other items will be
reinitialized automatically by a new current set value
or upon reallocation when an items compliment changes.
In the <pids> interface, any freeing of dynamic memory
could have been accomplished by adding that 'freefunc'
check to the 'assign' function. However, that requires
an Item_table test with every item. Instead, we'll now
satisfy such needs as the very first step in those set
functions responsible for dynamically acquired memory.
[ the <pids> api retains 2 'cleanup_stack' functions ]
[ to accommodate stack(s) 'reset' & to serve 'unref' ]
Lastly, all the 'itemize_stack' functions were tweaked
by eliminating an unnecessary initialization of result
unions. That objective was already accomplished by the
calloc() in a 'stacks_alloc' function or the remaining
'cleanup_stack' routine found in the <pids> interface.
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>
This patch will bring the <meminfo> API into line with
that proc(5) document. There were several undocumented
fields that were not noted and these two were omitted:
. 'MmapCopy' was conditional on the #define CONFIG_MMU
. 'Quicklists' depends on the #define CONFIG_QUICKLIST
And we're about to get the following new field in 4.20
which will be represented, at least, in that proc.txt:
. 'KReclaimable' will include SReclaimable plus others
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit removes some obsolete parameter validation
code which was needed back when certain functions were
public, called directly by users (1st/2nd generation).
Now that they're static they can be safely eliminated.
Signed-off-by: Jim Warner <james.warner@comcast.net>
With older library logic having been modified to avoid
using those potentially deadly alloc.h routines, while
improving 'errno' handling, we're ready to standardize
and enhance newlib's approach to any potential errors.
In so doing, we'll establish the following objectives:
. . . . . . . . . . . . . functions returning an 'int'
. an error will be indicated by a negative number that
is always the inverse of some well known errno.h value
. . . . . . . . . . . functions returning an 'address'
. any error will be indicated by a NULL return pointer
with the actual reason found in the formal errno value
And, when errno is manipulated directly we will strive
to do so whenever possible within those routines which
have been declared with PROCPS_EXPORT. In other words,
in the user callable functions defined in source last.
[ But, that won't always be possible. In particular, ]
[ all the 'read_failed' functions will sometimes set ]
[ 'errno' so that they can serve callers returning a ]
[ NULL or an int without duplicating a lot of logic. ]
[ Also, that includes one subordinate function which ]
[ was called by 'read_failed' in the <slabinfo> API. ]
------------------------------------------------------
Along the way, several additional miscellaneous issues
were addressed. They're listed here now for posterity.
. the '-1' return value passed outside the library was
eliminated since it would erroneously equate to -EPERM
. the stacks_fetch functions in <diskstats> and <stat>
weren't checked for their possible minus return values
. hash create was not checked in <meminfo> or <vmstat>
. fixed 'new' function faulty parm check in <slabinfo>
Signed-off-by: Jim Warner <james.warner@comcast.net>
. ensure whitespace exists between the code & comments
[ changing txt slightly keeps right margin alignment ]
. strive for more consistency with some comment styles
[ don't use C '/*' style where C++ '//' style exists ]
. removed the instance of double space in 1 assignment
[ still striving for consistency in whitespace usage ]
. fixed comment relating to number of 'derived fields'
[ the <meminfo> api recently added one new such enum ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
As an oversight, delta values for SWAP amounts weren't
included in the <meminfo> API. Since any runtime costs
of including them only amount to slightly more storage
this commit will simply correct the earlier oversight.
Signed-off-by: Jim Warner <james.warner@comcast.net>
The <meminfo> module attempted to duplicate the former
sysinfo memory calculations wherein 'SReclaimable' was
added to 'Cached' for the 'kb_main_cached' equivalent.
But, this original approach was wrong for two reasons.
1. The addition occurred too late to impact the 'USED'
calculation which could then cause an underflow in the
top memory display if 'SReclaimable' was heavily used.
2. In changing the actual /proc/meminfo 'Cached' value
it meant that users could not rely on that proc(5) man
page when interpreting the MEMINFO_MEM_CACHED results.
So this commit adds a new enumerator for the inclusive
cached amount plus repositions the calculation so that
a MEMINFO_MEM_USED result will exclude 'SReclaimable'.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Upon reflection, at the point where the 'priming read'
was introduced, any possibility of history distortions
was also eliminated. This was true because all of the
'old' (zeroed) data will have been replaced with 'new'
data whenever a user finally calls get, select & reap.
Thus, any DELTA values will automatically reflect that
interval between 'new' and subsequent retrieval calls.
[ diskstats didn't actually employ a 1st time switch ]
[ like the others so we have changed a comment only. ]
[ but that module will retain something similar used ]
[ inside node_update whenever a new node is created. ]
Reference(s):
. priming read added to slabinfo
commit 5d5a52a380
. priming read added to diskstats
commit ecd64f4445
. priming read added to meminfo, stat, vmstat
commit 1a2b62c779
Signed-off-by: Jim Warner <james.warner@comcast.net>
In each module employing a priming read at 'new' time,
should that read fail, a call to 'unref' will be made.
However, there is a hidden dependency that these calls
must never occur before the context 'refcount' was set
due to the way an 'unref' conditional was constructed.
So this commit just ensures that 'unref' will function
as expected, even if called with a 'refcount' of zero.
Signed-off-by: Jim Warner <james.warner@comcast.net>
A priming read at 'new' time in that <slabinfo> module
was important so that permission problems are detected
early. Plus, it also had the potential of making delta
values valid when 'get' or 'select' were first called.
It is for that latter reason that such a read was also
incorporated in the <diskstats> module 'new' function.
No other module, however, employed such priming reads.
This patch just brings those potential benefits to all
of our other newlib modules with the exception of that
<pids> guy. That module is, of necessity, sufficiently
different from those others to justify such exclusion.
Not only are there precious few DELTA enums in <pids>,
but the costs of a priming read would be much greater.
[ otherwise, these newly added priming reads have no ]
[ measurable negative impact on performance/timings. ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch will begin some refinements associated with
gprof. Initially, functions names have been changed to
help in identifying potential bottlenecks. This effort
also included the obscure set, free and sort routines.
Plus the following additional modifications were made:
. the stacks_alloc prologue was generalized plus added
to a couple of modules where it had not yet propagated
. a couple of the '// end ...' comments were corrected
. some functions have been formally tagged as 'inline'
Signed-off-by: Jim Warner <james.warner@comcast.net>
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>
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>
Rather than return a 0 result for all VAL type errors,
return what would have been without validation active.
This will enable a program like pgrep to still print a
result even though it used some incorrect type member.
With this commit, our VAL macro validations logic will
behave in exactly the same way as the GET validations.
While warning messages may be issued, except for a bad
enumerator, values will always be returned to callers.
Signed-off-by: Jim Warner <james.warner@comcast.net>
One ought not to assume that random memory access will
always succeed or, when it does, that an obviously bad
item enumerator will always be found at that location.
Thus, this patch corrects some really poor assumptions
associated with the 'xtra_procps_debug.h' header file.
[ and it does so in somewhat contorted ways so as to ]
[ avoid several darn gcc -Wnonnull warning messages! ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
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>
During development, we now have a means for validating
that a type referenced in application code matches the
actual type set by the library. The new feature can be
activated through either of the following two methods:
1) ./configure CFLAGS='-DXTRA_PROCPS_DEBUG' (all pgms)
2) an #include <proc/xtra-procps-debug.h> (single pgm)
[ in the future, one could add a formal configure.ac ]
[ provision. but for now a manual approach is safer. ]
Lastly, for any module which provides a sort function,
the handling for both 'noop' & 'extra' enumerators was
made consistent. Now, 'noop' is not sorted and 'extra'
will be sorted as that module's widest supported type.
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>
A collection of miscellaneous code and comment tweaks.
[ such changes will stop when desk checking ends too ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
Yes, all of these changes are strictly cosmetic. It is
likely symptomatic of some deep-seated character flaw.
[ or, it might be because of a certain pride in this ]
[ new library and the desire to make it even better! ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
Ever since their introduction, plus continuing through
several evolutions, both the meminfo and vmstat 'read'
functions employed a 'do while' loop for /proc access.
However, that loop construct was wrong since identical
tests were already done (twice!) within each loop body
itself, then accompanied by its own 'break' statement.
So, we will now transform them both into forever loops
which will help us to emphasize such break statements.
[ plus, let's return an error should nothing be read ]
[ lastly, eliminate 1 erroneous PROCPS_EXPORT prefix ]
Reference(s):
. original meminfo introduction
commit a20e88e4e7
. original vmstat introduction
commit a410e236ab
Signed-off-by: Jim Warner <james.warner@comcast.net>
As those 3rd generation newlib APIs evolved so too did
the extents_free_all() function. Most versions of this
function required the callers to first verify that the
extents anchor wasn't empty, which was poor etiquette.
This simple function should have been much more robust
and forgiving. With this commit, it fnally becomes so.
Signed-off-by: Jim Warner <james.warner@comcast.net>
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>
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>
After reviewing the hsearch code in glibc, performance
will almost certainly benefit from abandoning a strcmp
approach in favor of hashing, just like that <vmstat>.
[ As an aside, now having struggled toward that goal ]
[ of opaqueness & making our API as user friendly as ]
[ possible, haven't we earned the rights to evaluate ]
[ other implementations? For example, GNU's hsearch? ]
[ We expose none of our 'info' struct details to the ]
[ users, but GNU exposes their 'hsearch_data' thingy ]
[ right there in <search.h>. But worse, they require ]
[ the user to zero it out before 1st use. Jeeze, you ]
[ mean that a function called hcreate_r could not do ]
[ its own memset? Aw, come on GNU! What's with that? ]
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 patch was prompted through work on the <slabinfo>
upgrade from 2nd gen to 3rd. And while this assignment
caused no real harm, it most certainly was misleading.
[ plus add a couple of overlooked #undef directives! ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
When this interface was normalized/standardized, under
the commit referenced below, the parameters were never
validated in the 'get' function. Let's plug that hole.
Reference(s):
commit 407f1b71de
Signed-off-by: Jim Warner <james.warner@comcast.net>
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>
When the code for DELTA values (among other stuff) was
stolen from the recently revised <stat> interface, the
concept of ever growing values was propagated too. But
here we must manage both growing and shrinking values.
Thus former protections against a negative delta don't
have any place in this module and are hereby banished.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Thus function returns a pointer, not an int, so if there is
an error return NULL and not -errno.
proc/meminfo.c: In function ‘procps_meminfo_select’:
proc/meminfo.c:994:20: warning: return makes pointer from integer
without a cast [-Wint-conversion]
return -ENOMEM;
References:
commit 407f1b71de
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>
Not sure how this one has gone unnoticed until now but
with valgrind's help it's going bye-bye lickety-split.
Reference(s):
==26533== Conditional jump or move depends on uninitialised value(s)
==26533== at 0x4E4082B: procps_meminfo_stack_fill (meminfo.c:408)
Signed-off-by: Jim Warner <james.warner@comcast.net>
