tools/xentop/Makefile | 11 +++- tools/xentop/pcpu.c | 116 ++++++++++++++++++++++++++++++++++++++++++ tools/xentop/pcpu.h | 18 +++++++ tools/xentop/xentop.c | 30 +++++++++-- 4 files changed, 170 insertions(+), 5 deletions(-) create mode 100644 tools/xentop/pcpu.c create mode 100644 tools/xentop/pcpu.h
Introduce a new '-p/--pcpus' flag to display physical CPU utilization metrics
using xc_interface. This provides hypervisor-level CPU usage insights alongside
existing domain statistics.This helps correlate VM resource usage with host CPU
load patterns.
Changes:
- Add pcpu.c/pcpu.h for PCPU stat collection logic
- Link against libxenctrl for xc_handle access
- Extend CLI with '-p' flag and output formatting
- Forward declare xenstat_handle to access xc_handle
- Include cleanup for PCPU resources in exit handler
Example usage:
xentop -p # Shows physical CPU stats
xentop -bp # Batch mode
Example output with '-p':
NAME STATE CPU(%) MEM(%) VCPUS ...
Domain-0 -----r 17.0 6.3 8
DomD -----r 767.0 38.1 8
Physical CPU Usage:
┌───────┬────────┐
│ Core │ Usage │
├───────┼────────┤
│ 0 │ 98.1% │
│ ... │ ... │
│ 7 │ 97.3% │
└───────┴────────┘
Signed-off-by: Jahan Murudi <jahan.murudi.zg@renesas.com>
---
tools/xentop/Makefile | 11 +++-
tools/xentop/pcpu.c | 116 ++++++++++++++++++++++++++++++++++++++++++
tools/xentop/pcpu.h | 18 +++++++
tools/xentop/xentop.c | 30 +++++++++--
4 files changed, 170 insertions(+), 5 deletions(-)
create mode 100644 tools/xentop/pcpu.c
create mode 100644 tools/xentop/pcpu.h
diff --git a/tools/xentop/Makefile b/tools/xentop/Makefile
index 70cc2211c5..91d3ea864a 100644
--- a/tools/xentop/Makefile
+++ b/tools/xentop/Makefile
@@ -15,6 +15,7 @@ include $(XEN_ROOT)/tools/Rules.mk
CFLAGS += -DGCC_PRINTF $(CFLAGS_libxenstat)
LDLIBS += $(LDLIBS_libxenstat) $(CURSES_LIBS) $(TINFO_LIBS) $(SOCKET_LIBS) -lm
+LDLIBS += $(LDLIBS_libxenctrl)
CFLAGS += -DHOST_$(XEN_OS)
# Include configure output (config.h)
@@ -25,8 +26,14 @@ TARGETS := xentop
.PHONY: all
all: $(TARGETS)
-xentop: xentop.o
- $(CC) $(LDFLAGS) -o $@ $< $(LDLIBS) $(APPEND_LDFLAGS)
+xentop: xentop.o pcpu.o
+ $(CC) $(LDFLAGS) -o $@ $^ $(LDLIBS) $(APPEND_LDFLAGS)
+
+pcpu.o: pcpu.c pcpu.h
+ $(CC) $(CFLAGS) -c $< -o $@
+
+%.o: %.c
+ $(CC) $(CFLAGS) -c $< -o $@
.PHONY: install
install: all
diff --git a/tools/xentop/pcpu.c b/tools/xentop/pcpu.c
new file mode 100644
index 0000000000..6b0f2a8d3c
--- /dev/null
+++ b/tools/xentop/pcpu.c
@@ -0,0 +1,116 @@
+#include "pcpu.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/time.h>
+
+#define MAX_PCPUS 128
+
+// Convert Xen's idle time (nanoseconds) to microseconds to match gettimeofday()
+#define XEN_IDLETIME_TO_USEC(idle) ((idle) / 1000)
+
+// File-scope variables (static for module privacy)
+static pcpu_stat_t *pcpu_stats = NULL;
+static int num_pcpus = 0;
+static uint64_t *prev_idle = NULL;
+static uint64_t *prev_total = NULL;
+
+int update_pcpu_stats(xc_interface *xch)
+{
+ struct xen_sysctl_cpuinfo info[MAX_PCPUS];
+ struct timeval now;
+ int nr_cpus = 0;
+ int i;
+
+ if (!xch || xc_getcpuinfo(xch, MAX_PCPUS, info, &nr_cpus) < 0) {
+ return -1;
+ }
+
+ gettimeofday(&now, NULL);
+ uint64_t current_total = (uint64_t)now.tv_sec * 1000000 + now.tv_usec;
+
+ /* Allocate memory if needed */
+ if (!pcpu_stats || nr_cpus > num_pcpus) {
+ pcpu_stat_t *new_stats = realloc(pcpu_stats, nr_cpus * sizeof(pcpu_stat_t));
+ uint64_t *new_prev_idle = realloc(prev_idle, nr_cpus * sizeof(uint64_t));
+ uint64_t *new_prev_total = realloc(prev_total, nr_cpus * sizeof(uint64_t));
+
+ if (!new_stats || !new_prev_idle || !new_prev_total) {
+ free(new_stats);
+ free(new_prev_idle);
+ free(new_prev_total);
+ return -1;
+ }
+
+ pcpu_stats = new_stats;
+ prev_idle = new_prev_idle;
+ prev_total = new_prev_total;
+ num_pcpus = nr_cpus;
+
+ /* Initialize previous values (skip first calculation) */
+ for (i = 0; i < nr_cpus; i++) {
+ prev_idle[i] = XEN_IDLETIME_TO_USEC(info[i].idletime);
+ prev_total[i] = current_total;
+ pcpu_stats[i].pcpu_id = i;
+ /* Default to 0% on first run */
+ pcpu_stats[i].usage_pct = 0.0;
+ }
+ return 0;
+ }
+
+ /* Calculate CPU usage */
+ for (i = 0; i < nr_cpus; i++) {
+ uint64_t current_idle = XEN_IDLETIME_TO_USEC(info[i].idletime);
+ uint64_t idle_diff = current_idle - prev_idle[i];
+ uint64_t total_diff = current_total - prev_total[i];
+
+ if (total_diff > 0) {
+ double usage = 100.0 * (1.0 - ((double)idle_diff / total_diff));
+ pcpu_stats[i].usage_pct = (usage < 0) ? 0 : (usage > 100) ? 100 : usage;
+ } else {
+ pcpu_stats[i].usage_pct = 0.0;
+ }
+ pcpu_stats[i].pcpu_id = i;
+ /* Update history */
+ prev_idle[i] = current_idle;
+ prev_total[i] = current_total;
+ }
+
+ return 0;
+}
+
+void print_pcpu_stats(void)
+{
+ if (!pcpu_stats || num_pcpus == 0) {
+ printf("No PCPU data available\n");
+ return;
+ }
+
+ printf("\nPhysical CPU Usage:\n");
+
+ // Print table header
+ printf("┌───────┬────────┐\n");
+ printf("│ Core │ Usage │\n");
+ printf("├───────┼────────┤\n");
+
+ // Print each CPU's data
+ for (int i = 0; i < num_pcpus; i++) {
+ printf("│ %-5d │ %5.1f%% │\n",
+ pcpu_stats[i].pcpu_id,
+ pcpu_stats[i].usage_pct);
+ }
+
+ // Print table footer
+ printf("└───────┴────────┘\n");
+}
+
+void free_pcpu_stats(void)
+{
+ free(pcpu_stats);
+ free(prev_idle);
+ free(prev_total);
+ pcpu_stats = NULL;
+ prev_idle = NULL;
+ prev_total = NULL;
+ num_pcpus = 0;
+}
diff --git a/tools/xentop/pcpu.h b/tools/xentop/pcpu.h
new file mode 100644
index 0000000000..889efacf3c
--- /dev/null
+++ b/tools/xentop/pcpu.h
@@ -0,0 +1,18 @@
+#ifndef PCPU_H
+#define PCPU_H
+
+#include <xenctrl.h>
+#include <stdbool.h>
+#include <xenstat.h>
+
+typedef struct {
+ int pcpu_id;
+ float usage_pct;
+} pcpu_stat_t;
+
+/* Public API */
+int update_pcpu_stats(xc_interface *xch);
+void print_pcpu_stats(void);
+void free_pcpu_stats(void);
+
+#endif // PCPU_H
\ No newline at end of file
diff --git a/tools/xentop/xentop.c b/tools/xentop/xentop.c
index f5d6c19cf9..477299c883 100644
--- a/tools/xentop/xentop.c
+++ b/tools/xentop/xentop.c
@@ -24,6 +24,7 @@
#include <ctype.h>
#include <errno.h>
#include <math.h>
+#include "pcpu.h"
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
@@ -69,6 +70,12 @@
#define INT_FIELD_WIDTH(n) ((unsigned int)(log10(n) + 1))
+/* TEMPORARY: Forward declare the internal structure */
+struct xenstat_handle {
+ xc_interface *xc_handle;
+ /* Other members don't matter fo now */
+};
+
/*
* Function prototypes
*/
@@ -205,6 +212,7 @@ field_id sort_field = FIELD_DOMID;
unsigned int first_domain_index = 0;
unsigned int delay = 3;
unsigned int batch = 0;
+static unsigned int show_pcpus = 0;
unsigned int loop = 1;
unsigned int iterations = 0;
int show_vcpus = 0;
@@ -240,6 +248,7 @@ static void usage(const char *program)
"-r, --repeat-header repeat table header before each domain\n"
"-v, --vcpus output vcpu data\n"
"-b, --batch output in batch mode, no user input accepted\n"
+ "-p, --pcpus show physical CPU stats\n"
"-i, --iterations number of iterations before exiting\n"
"-f, --full-name output the full domain name (not truncated)\n"
"-z, --dom0-first display dom0 first (ignore sorting)\n"
@@ -267,6 +276,8 @@ static void cleanup(void)
xenstat_free_node(cur_node);
if(xhandle != NULL)
xenstat_uninit(xhandle);
+
+ free_pcpu_stats();
}
/* Display the given message and gracefully exit */
@@ -1189,7 +1200,7 @@ static void top(void)
fail("Failed to retrieve statistics from libxenstat\n");
/* dump summary top information */
- if (!batch)
+ if (!batch && !show_pcpus)
do_summary();
/* Count the number of domains for which to report data */
@@ -1245,9 +1256,18 @@ static void top(void)
do_vbd(domains[i]);
}
- if (!batch)
+ if (!batch && !show_pcpus )
do_bottom_line();
+ if (show_pcpus && xhandle != NULL ) {
+ if (update_pcpu_stats(xhandle->xc_handle) == 0) {
+ print_pcpu_stats();
+ }
+ else {
+ print("Error getting PCPU stats\n");
+ }
+ }
+
free(domains);
}
@@ -1272,12 +1292,13 @@ int main(int argc, char **argv)
{ "vcpus", no_argument, NULL, 'v' },
{ "delay", required_argument, NULL, 'd' },
{ "batch", no_argument, NULL, 'b' },
+ { "pcpus", no_argument, NULL, 'p' },
{ "iterations", required_argument, NULL, 'i' },
{ "full-name", no_argument, NULL, 'f' },
{ "dom0-first", no_argument, NULL, 'z' },
{ 0, 0, 0, 0 },
};
- const char *sopts = "hVnxrvd:bi:fz";
+ const char *sopts = "hVnxrvd:bpi:fz";
if (atexit(cleanup) != 0)
fail("Failed to install cleanup handler.\n");
@@ -1312,6 +1333,9 @@ int main(int argc, char **argv)
case 'b':
batch = 1;
break;
+ case 'p':
+ show_pcpus = 1;
+ break;
case 'i':
iterations = atoi(optarg);
loop = 0;
--
2.34.1
On 08.07.2025 13:46, Jahan Murudi wrote: > --- a/tools/xentop/Makefile > +++ b/tools/xentop/Makefile > @@ -15,6 +15,7 @@ include $(XEN_ROOT)/tools/Rules.mk > > CFLAGS += -DGCC_PRINTF $(CFLAGS_libxenstat) > LDLIBS += $(LDLIBS_libxenstat) $(CURSES_LIBS) $(TINFO_LIBS) $(SOCKET_LIBS) -lm > +LDLIBS += $(LDLIBS_libxenctrl) > CFLAGS += -DHOST_$(XEN_OS) > > # Include configure output (config.h) > @@ -25,8 +26,14 @@ TARGETS := xentop > .PHONY: all > all: $(TARGETS) > > -xentop: xentop.o > - $(CC) $(LDFLAGS) -o $@ $< $(LDLIBS) $(APPEND_LDFLAGS) > +xentop: xentop.o pcpu.o > + $(CC) $(LDFLAGS) -o $@ $^ $(LDLIBS) $(APPEND_LDFLAGS) > + > +pcpu.o: pcpu.c pcpu.h > + $(CC) $(CFLAGS) -c $< -o $@ > + > +%.o: %.c > + $(CC) $(CFLAGS) -c $< -o $@ As you mean to re-submit, you may also want to tidy (back) the above. You don't say why you need to spell out both the explicit and the pattern rule here. And I don't think this is actually necessary. All you ought to need is indeed the addition of the extra prereq object file. Jan
Hi Jan, Thank you for your review. > On 08/07/ 2025 19:15, Jan Beulich wrote: >> +pcpu.o: pcpu.c pcpu.h >> + $(CC) $(CFLAGS) -c $< -o $@ >> + >> +%.o: %.c >> + $(CC) $(CFLAGS) -c $< -o $@ > As you mean to re-submit, you may also want to tidy (back) the above. You don't say why you need to spell out both the explicit and the pattern rule here. And I don't think this is actually necessary. All you ought to need is indeed the addition of the extra prereq object file. You're right - these explicit rules are redundant. In v2 of the RFC patch, I've removed both the explicit pcpu.o rule and the pattern rule. https://patchwork.kernel.org/project/xen-devel/patch/20250709082810.3052544-1-jahan.murudi.zg@renesas.com/ Regards, Jahan Murudi
> diff --git a/tools/xentop/xentop.c b/tools/xentop/xentop.c
> index f5d6c19cf9..477299c883 100644
> --- a/tools/xentop/xentop.c
> +++ b/tools/xentop/xentop.c
> @@ -69,6 +70,12 @@
>
> #define INT_FIELD_WIDTH(n) ((unsigned int)(log10(n) + 1))
>
> +/* TEMPORARY: Forward declare the internal structure */
> +struct xenstat_handle {
> + xc_interface *xc_handle;
> + /* Other members don't matter fo now */
> +};
> +
What makes this temporary? Is there a follow-up patch?
Or should this be an [RFC] instead of a [PATCH]?
> @@ -240,6 +248,7 @@ static void usage(const char *program)
> "-r, --repeat-header repeat table header before each
domain\n"
> "-v, --vcpus output vcpu data\n"
> "-b, --batch output in batch mode, no user input
accepted\n"
> + "-p, --pcpus show physical CPU stats\n"
> "-i, --iterations number of iterations before exiting\n"
> "-f, --full-name output the full domain name (not
truncated)\n"
> "-z, --dom0-first display dom0 first (ignore sorting)\n"
Incorrect indentation here
> @@ -1245,9 +1256,18 @@ static void top(void)
> do_vbd(domains[i]);
> }
>
> - if (!batch)
> + if (!batch && !show_pcpus )
> do_bottom_line();
>
> + if (show_pcpus && xhandle != NULL ) {
> + if (update_pcpu_stats(xhandle->xc_handle) == 0) {
> + print_pcpu_stats();
> + }
> + else {
> + print("Error getting PCPU stats\n");
> + }
> + }
> +
and here
Hi Andriy,
Thank you for your review.
>On 08/07/ 2025 18:26, Andriy Sultanov wrote:
> > diff --git a/tools/xentop/xentop.c b/tools/xentop/xentop.c > index f5d6c19cf9..477299c883 100644 > --- a/tools/xentop/xentop.c > +++ b/tools/xentop/xentop.c > @@ -69,6 +70,12 @@ > > #define INT_FIELD_WIDTH(n) ((unsigned int)(log10(n) + 1)) > > +/* TEMPORARY: Forward declare the internal structure */ > +struct xenstat_handle { > + xc_interface *xc_handle; > + /* Other members don't matter fo now */ > +}; > +
> What makes this temporary? Is there a follow-up patch?
This was intended as a short-term solution to access the xc_handle. Latter may be move this to a shared header if multiple tools need access.
> Or should this be an [RFC] instead of a [PATCH]?
You're right - I'll resubmit this as an RFC patch.
> > @@ -240,6 +248,7 @@ static void usage(const char *program) > "-r, --repeat-header repeat table header before each domain\n"
> > "-v, --vcpus output vcpu data\n"
> > "-b, --batch output in batch mode, no user input accepted\n"
> > + "-p, --pcpus show physical CPU stats\n"
> > "-i, --iterations number of iterations before exiting\n"
> > "-f, --full-name output the full domain name (not truncated)\n"
> > "-z, --dom0-first display dom0 first (ignore sorting)\n"
> Incorrect indentation here
You're correct. I'll fix both the -b and -p options to maintain consistent
alignment with the other options in the v2 RFC patch
>> @@ -1245,9 +1256,18 @@ static void top(void) > do_vbd(domains[i]); > } > > - if (!batch) > + if (!batch && !show_pcpus ) > do_bottom_line(); > > + if (show_pcpus && xhandle != NULL ) { > + if (update_pcpu_stats(xhandle->xc_handle) == 0) { > + print_pcpu_stats(); > + } > + else { > + print("Error getting PCPU stats\n"); > + } > + } > +
> and here
Good catch on the indentation issues.
Regards,
Jahan
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