Commit Graph

2 Commits

Author SHA1 Message Date
Jim Warner
387d4030f4 library: miscellaneous tweaks to pid code and comments
. 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>
2015-08-23 21:08:18 +10:00
Jim Warner
7e6a371d8a library: implement task/thread support via the new api
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>
2015-08-23 21:05:06 +10:00