According to the Linux kernel documentation, "SwapCached" tracks "memory
that once was swapped out, is swapped back in but still also is
in the swapfile (if memory is needed it doesn't need to be swapped out
AGAIN because it is already in the swapfile. This saves I/O)."
Use only one enum instead of a global and a platform specific one.
Drop Platform_numberOfFields global variable.
Set known size of Process_fields array
This acheives two things:
- Allows for simple tie-breaking if values compare equal (needed to make sorting the tree-view stable)
- Allows for platform-dependent overriding of the sort-order for specific fields
Also fixes a small oversight on DragonFlyBSD when default-sorting.
* This removes duplicated code that adjusts the sort direction from every
OS-specific folder.
* Most fields in a regular htop screen are OS-independent, so trying
Process_compare first and only falling back to the OS-specific
compareByKey function if it's an OS-specific field makes sense.
* This will allow us to override the sortKey in a global way without having
to edit each OS-specific file.
By storing the per-process m_resident and m_virt values in the form
htop wants to display them in (KB, not pages), we no longer need to
have definitions of pageSize and pageSizeKB in the common CRT code.
These variables were never really CRT (i.e. display) related in the
first place. It turns out the darwin platform code doesn't need to
use these at all (the process values are extracted from the kernel
in bytes not pages) and the other platforms can each use their own
local pagesize variables, in more appropriate locations.
Some platforms were actually already doing this, so this change is
removing duplication of logic and variables there.
RichString_writeFrom takes a top spot during performance analysis due to the
calls to mbstowcs() and iswprint().
Most of the time we know in advance that we are only going to print regular
ASCII characters.
The global ProcessList structure contains a couple of unused
fields. 'sharedMem' has never been used by any Meter, since
its not been anything other than zero in Linux /proc/meminfo
for many, many years. The freeMem field is only used in the
usedMem calculation, so it can reside on the stack like some
other memory variables used within-calculations-only and not
exposed to the user via a Meter.
Move platform-specific code out of the htop.c main function
and into the platform sub-directories - primarily this is
the Linux procfs path check and sensors setup/teardown; not
needed on any other platforms. No functional changes here.
If currently two unsigned values are compared via `a - b`, in the case b
is actually bigger than a, the result will not be an negative number (as
-1 is expected) but a huge positive number as the subtraction is an
unsigned subtraction.
Avoid over-/underflow affected operations; use comparisons.
Modern compilers will generate sane code, like:
xor eax, eax
cmp rdi, rsi
seta al
sbb eax, 0
ret
Generic data, as CPU and memory usage, are used by Meters.
In paused mode they would stop receiving updates and especially Graph
Meters would stop showing continuous data.
Improves: #214Closes: #253
man:sysconf(3) states:
The values obtained from these functions are system configuration constants.
They do not change during the lifetime of a process.
Add a date meter and sort header and source files in Makefile
Change the lists of header and source files sorted alphabetical and one
file per line. This way diffs become better readable and merges easier.
This is a straightforward extension of the existing multi-column CPU meter
code, which now allows for up CPU meters to be displayed in up to 16 columns.
This also adds the meter declarations to all the platform-specific code.
The MIN, MAX, CLAMP, MINIMUM, and MAXIMUM macros appear
throughout the codebase with many re-definitions. Make
a single copy of each in a common header file, and use
the BSD variants of MINIMUM/MAXIMUM due to conflicts in
the system <sys/param.h> headers.
Reasoning:
- implementation was unsound -- broke down when I added a fairly
basic macro definition expanding to a struct initializer in a *.c
file.
- made it way too easy (e.g. via otherwise totally innocuous git
commands) to end up with timestamps such that it always ran
MakeHeader.py but never used its output, leading to overbuild noise
when running what should be a null 'make'.
- but mostly: it's just an awkward way of dealing with C code.
The current OpenBSD-specific CPU usage code is broken. The `cpu`
parameter of `Platform_setCPUValues` is an integer in the interval
[0, cpuCount], not [0, cpuCount-1]: Actual CPUs are numbered from
1, the “zero” CPU is a “virtual” one which represents the average
of actual CPUs (I guess it’s inherited from Linux’s `/proc/stats`).
This off-by-one error leads to random crashes.
Moreover, the displayed CPU usage is more detailed with system,
user and nice times.
I made the OpenBSD CPU code more similar to the Linux CPU code,
removing a few old bits from OpenBSD’s top(1). I think it will be
easier to understand, maintain and evolve.
I’d love some feedback from experienced OpenBSD people.
The source code correctly states that the maximum PID number in
the OpenBSD kernel is fixed in sys/sys/proc.h, however this was
updated in revision 1.215 (two years ago!) from 32766 to 99999.
Introduction of CP_SPIN sched state broke hard-coded state indexes
resulting in the meters incorrectly reporting bogus intr data instead of
CPU usage. Change hardcoded values to sched.h macros.
Specifically, Platform_signals[] and Platform_numberOfSignals. Both are
not supposed to be mutable. Marking them 'const' puts them into rodata
sections in binary. And for Platform_numberOfSignals, this aids
optimization (aids only Link Time Optimization for now). :)
Signed-off-by: Kang-Che Sung <explorer09@gmail.com>
Namely:
o use malloc where an xCalloc slipped in
o safeguard against an empty arg list - I don't think it's possible,
but it would be potentially exploitable
o we need to initialize the arg string to an empty string because we no
longer use strlcpy(3)
o annotate a tricky use of strlcpy(3)'s truncation
Including:
o set *basenameEnd even in error cases (FreeBSD probably needs this)
o use kvm_openfiles(3) rather than kvm_open(3) so that we can report
errors (as with FreeBSD)
o sanify the process argument list creation by using strlcat(3)
o drop the pageSizeKb variable and use the PAGE_SIZE_KB macro directly,
as the page size can't change anyway
o clean up a few macros, add MINIMUM() and MAXIMUM() (should be
mirrored to FreeBSD)
o fix some syntax
o add some useful comments
With the CLAMP macro replacing the combination of MIN and MAX, we will
have at least two advantages:
1. It's more obvious semantically.
2. There are no more mixes of confusing uses like MIN(MAX(a,b),c) and
MAX(MIN(a,b),c) and MIN(a,MAX(b,c)) appearing everywhere. We unify
the 'clamping' with a single macro.
Note that the behavior of this CLAMP macro is different from
the combination `MAX(low,MIN(x,high))`.
* This CLAMP macro expands to two comparisons instead of three from
MAX and MIN combination. In theory, this makes the code slightly
smaller, in case that (low) or (high) or both are computed at
runtime, so that compilers cannot optimize them. (The third
comparison will matter if (low)>(high); see below.)
* CLAMP has a side effect, that if (low)>(high) it will produce weird
results. Unlike MIN & MAX which will force either (low) or (high) to
win. No assertion of ((low)<=(high)) is done in this macro, for now.
This CLAMP macro is implemented like described in glib
<http://developer.gnome.org/glib/stable/glib-Standard-Macros.html>
and does not handle weird uses like CLAMP(a++, low++, high--) .
This is what OpenBSD's top(1) does when the libkvm call fails, and it's
a good idea.
This commit also fixes process name construction. The space was being
written one character too far.
Daniel Lange