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>
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>
With this patch, all of the modules which offer a reap
function (pids, diskstats, slabinfo and stat too) will
now also provide for sorting whatever had been reaped.
It was easy to overlook a sort function for our <STAT>
guy given the paucity of CPUs on your typical personal
desktop or laptop. However, out in the world one might
find boxes with hundreds of CPUs plus many NUMA nodes.
Hey, who are we to disallow sorts on something another
person might see as useful under the above conditions?
And, there's always something to be said for symmetry.
[ of course, several minor tweaks were also included ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
. a more appropriate error return code was substituted
. a safer form of comparison is utilized in two places
. a STAT_VAL macro replaced by more proper MEMINFO_VAL
. several of the silly 'xerrx' formats had been missed
. a few whitespace changes have also been incorporated
Signed-off-by: Jim Warner <james.warner@comcast.net>
With this patch we've completed a progression toward a
standard approach to naming conventions which follows:
* Only functions will begin with that 'procps_' prefix
. ........................................... examples
. procps_vmstat_get ()
. procps_diskstats_select ()
- ----------------------------------------------------
* Exposed structures begin with the module/header name
. ........................................... examples
. struct pids_info
. struct stat_reaped
- ----------------------------------------------------
* Item enumerators begin like structs, but capitalized
. ........................................... examples
. VMSTAT_COMPACT_FAIL
. MEMINFO_DELTA_ACTIVE
[ slabinfo varies slightly due to some item variants ]
. SLABINFO_extra
. SLABS_SIZE_ACTIVE
. SLABNODE_OBJS_PER_SLAB
[ could cure with a prefix of SLABINFO, but too long ]
- ----------------------------------------------------
* Other enumerators work exactly like item enumerators
. ........................................... examples
. PIDS_SORT_ASCEND
. STAT_REAP_CPUS_AND_NODES
- ----------------------------------------------------
* Macros and constants begin just like the enumerators
. ........................................... examples
. #define SLABINFO_GET
. #define DISKSTATS_TYPE_DISK
- ----------------------------------------------------
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>
This patch will bring this interface up to our 3rd gen
standards. The following summarizes the major changes.
* New delta provisions have been added to most fields.
There are, of course, some fields for which a delta is
inappropriate. They include the identifying items such
as name, type, major and minor. Plus the io_inprogress
field which already acts, in effect, as a delta value.
* To provide delta support, dev_node historical values
have become persistent. By the same token, the library
must provide for future removal of disks/partitions. A
timestamp is used to detect 'stale' data which will be
deleted so as not to satisfy some get, select or reap.
* Such persistent support is provided by a linked list
which, by default, grows from the bottom down so as to
maintain compatibility with the /proc/diskstats order.
Initially, I was tempted to use the GNU tsearch (tree)
provisions until I discovered the overhead of building
that tree plus costs of a subsequent 'twalk'. Besides,
walking such a tree means retrieval order would differ
from an order required/expected by the vmstat program.
* The '/sys/block' directory is no longer scanned with
every refresh cycle. Rather, it's only accessed when a
node is first encountered. Then, that node's 'type' is
persistent for its lifetime like several other fields.
* A sort provision was included, at virtually no cost,
even though such a provision was not currently needed.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Where possible, libprocps files convey the name of the
actual source pseudo file under the '/proc' directory.
This brings diskstats into line with such an approach.
Signed-off-by: Jim Warner <james.warner@comcast.net>
[ plus we also play catch up on some earlier changes ]
[ that impacted skill.c, after using --enable-skill! ]
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>
That #define QUICK_THREADS was impossible to implement
under the new <pids> interface. Plus it was also found
to distort some thread information (referenced below).
So, it's always been inactive under the newlib branch.
However, it will (with small changes) still serve some
useful purpose in our library. Now, when the redefined
FALSE_THREADS is active, those special strings showing
"[ duplicate ENUM ]" will appear for any child thread.
Note: the real reason for such strings appearing isn't
being exercised, only their mechanics. In actual usage
they are substituted when a user duplicates such items
in a results stack & only the 1st instance can own it.
With this patch, we are simply fooling the <pids> code
into thinking an item was duplicated via a NULL value.
Reference(s):
. from master branch
commit 25a6ecdbfb
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>
The procps library attempts to work out the tty of a process
through several methods. For things like /dev/tty123 or
/dev/foo it works fine.
For tty devices that put the minor number in a directory
of the major name this fails. So then we have to fallback
to stating things like the processes STDERR and try again.
Considering a lot of processes sit on ttys such as
/dev/pts/3 this is a lot of wasted time. At the point of
entering driver_name we know "/dev/pts" and we know "3"
we just didn't join them up the right way as this is old
code.
This change now looks for /dev/pts/3 as well. It does it
after looking for /dev/pts3 so the behaviour is the same.
References:
https://bugs.debian.org/770215
Signed-off-by: Craig Small <csmall@enc.com.au>
This commit brings all of those 'fetch' type functions
(supporting some form of 'reap') into closer alignment
with one another. The biggest impact is to be found in
the <stat> module, which now provides for the separate
copy of stack pointers which will be exposed to users.
The reason such a copy was not employed initially with
<stat>, unlike those for <pids> and <slabinfo>, is due
to the fact that such stacks were never sortable. Thus
the original raw consolidated extent pointers wouldn't
have been disturbed. But that meant no NULL delimiter.
So with this commit, all reap/fetch operations now use
pointer copies when returning results to callers. And,
all such arrays are now NULL delimited meaning callers
can choose their own access fencepost: totals or NULL.
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit will consolidate the three separate copies
of the item enumerators currently supporting that reap
function (summary, cpus & nodes) into one shared copy.
That select function will continue to maintain its own
dedicated items copy, albeit via a new item structure.
[ and while we're at it, we'll move the 'select' guy ]
[ to its proper alphabetical place, after our 'reap' ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
Unlike other cached string fields (such as USER name),
that lxcname field was defined as 'const char *'. This
required a custom 'set' function using a cast in order
to avoid a compiler warning regarding that assignment.
So this commit brings lxcname into line with all those
other cached string fields. And while we're at it, the
reason some string fields have no 'freefunc' will also
be explained with some new comments in the Item_table.
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>
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 partial revert of the commit
referenced below. And, so that yours truly (the author
for goodness sake) doesn't shoot his tootsies again in
the future, a cautionary programmer comment was added.
Reference(s):
commit dea4033418
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>
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>
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>
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>
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>
All our numa logic was well encapsulated under #ifndef
NUMA_DISABLE (as ./configure --disable-numa), with the
exception of 1 case label. The reason it didn't create
any problems is because the sole consumer (top) itself
responded to the presence of #define NUMA_DISABLE too.
But if that option wasn't used, an oops still awaited.
When experimenting with a 32-bit library plus a 64-bit
kernel, a bug was revealed should the numa library not
have been found. Our 'reap' function must tolerate the
potential of a 0 return from that stacks_fetch_tics().
Now, if numa is desired but not possible, we'll be ok.
[ and, we'll build numa history from fresher sources ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
On MacOS the system already has user_from_uid and group_from_gid.
These are renamed pwcache_get_user and pwcache_get_group.
They were also exported but did not appear in the symbol file
or used by any of the procps binaries. They are no longer exported.
References:
https://gitlab.com/procps-ng/procps/issues/34
Signed-off-by: Craig Small <csmall@enc.com.au>
When those items were made dynamic at 'new' time, some
other functions, previously assured of their presence,
failed to verify a 'reset' had acually been requested.
This commit just corrects that oversight and avoids an
attempt to 'assign_results' when no items are present.
Reference(s):
. when items/numitems became optional
commit 9ebadc1438
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>
The 'procps.h' header includes all other headers which
contain exported (public) functions, while this header
has some (private) macros required for implementation.
If we mix the two, by including procps.h in this file,
we'll lose all hope of the compiler catching the kinds
of errors corrected in an immediately preceding patch.
[ we must be diligent, always constantly striving to ]
[ protect jimmy from ill effects due to copy & paste ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
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>
Though all those callback's parameters are ignored and
qsort treats them as pointers to void, it's wrong when
3rd parm is 'enum pids_item', not 'struct sort_parms'.
So we will fix it in a way that lessens the likelihood
of another such a mistake when some new type is added.
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>
After normalizing the <SLABINFO> module, much of which
was based on this module, a structure which is crucial
to concurrent select/reap support is renamed the same.
Such a need for concurrent support was revealed during
slabtop testing. That program requests (select) global
data after calling for individual node data (reap) but
before those stacks have been accessed. Therefore, one
set of 'items'/'extents' could not possibly be shared.
So now we will know the former struct fetch_support as
ext_support. The former name was potentially confusing
since the struct was used by both 'select' and 'reap'.
However, only 'reap' ever called the 'fetch' function.
[ this <STAT> already accommodated concurrent usage. ]
[ in fact it contains 3 separate sets of items/exts. ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
Oops, the PROCPS_VMSTAT_logical_end enum reflected the
source state before all those DELTA enum's were added.
[ plus add a couple of overlooked #undef directives, ]
[ and whack an unneeded stacks_alloc assignment too! ]
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>
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
------------------------------------------------------
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.
------------------------------------------------------
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>
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>
The original test did not NULL the unallocated info pointer. This
was incorrectly calling the procps_pids_new() function.
Signed-off-by: Craig Small <csmall@dropbear.xyz>
This interface represented a 2nd generation attempt at
the opaque newlib approach. In other words, it did not
involve the 1st generation 'chains'. Instead, 'stacks'
were employed. But the interface wasn't user friendly.
Users were required to create their own stacks, before
calling 'getstack' to retrieve multiple results with a
single call. Even worse, sometimes 'read' was required
before calling 'get' when working with single results.
So this commit represents the 3rd generation approach.
We eliminate the burden of 'read' and creating stacks.
Rather, beyond those standard 'new', 'ref' and 'unref'
functions, we'll offer just 'get' (single result) plus
a 'select' function (for multiple results in 1 stack).
And along the way, this commit vastly expands the data
extracted from /proc/vmstat. All values that currently
exist (and their delta equivalents) are now available.
Deltas were included for everything because there's no
real runtime costs beyond using a little extra memory.
The only problem is a lack of documentation for all of
those fields, as is reflected in the references below.
Oh well, maybe someday someone will dig through kernel
sources & finally plug that rather large document gap.
[ as an aside, rather than using a 'strcmp' approach ]
[ when parsing the /proc/vmstat file, as is found in ]
[ the <meminfo> module, we exploit those hash search ]
[ provisions that are found in the <search.h> header ]
Reference(s):
http://www.spinics.net/lists/linux-man/msg09096.htmlhttp://www.linuxinsight.com/proc_vmstat.html
Signed-off-by: Jim Warner <james.warner@comcast.net>
With an eye to the future, rather than managing a long
switch/case construct in the procps_stat_get function,
we'll adopt the approach used in the <meminfo> module.
By making 'get' processing table driven too, just like
'select' is already, that may ease future maintenance.
Along the way a rather large boo-boo was fixed dealing
with that /proc/stat 'procs_running' field which crept
in with the commit referenced below. It wasn't spelled
correctly and thus was never captured as PROC_RUNNING.
Reference(s):
commit abc71a46ad
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>
