David Vrabel
2013-Feb-21 17:57 UTC
[PATCH 3/4] kexec/xen: use libxc to get location of crash notes
From: David Vrabel <david.vrabel@citrix.com>
Use xc_kexec_get_range(KEXEC_RANGE_MA_CPU) instead of parsing
/proc/iomem (which is only populated by non-upstream ("classic") Xen
kernels).
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
---
kexec/crashdump-xen.c | 61 ++++++++++++++++++++++++++++---------------------
1 files changed, 35 insertions(+), 26 deletions(-)
diff --git a/kexec/crashdump-xen.c b/kexec/crashdump-xen.c
index ff4706c..13335a5 100644
--- a/kexec/crashdump-xen.c
+++ b/kexec/crashdump-xen.c
@@ -163,42 +163,51 @@ unsigned long xen_architecture(struct crash_elf_info
*elf_info)
return machine;
}
-static int xen_crash_note_callback(void *UNUSED(data), int nr,
- char *UNUSED(str),
- unsigned long base,
- unsigned long length)
-{
- struct crash_note_info *note = xen_phys_notes + nr;
-
- note->base = base;
- note->length = length;
-
- return 0;
-}
-
+#ifdef HAVE_LIBXENCTRL
int xen_get_nr_phys_cpus(void)
{
- char *match = "Crash note\n";
- int cpus, n;
+ xc_interface *xc;
+ int cpu;
if (xen_phys_cpus)
return xen_phys_cpus;
- if ((cpus = kexec_iomem_for_each_line(match, NULL, NULL))) {
- n = sizeof(struct crash_note_info) * cpus;
- xen_phys_notes = malloc(n);
- if (!xen_phys_notes) {
- fprintf(stderr, "failed to allocate xen_phys_notes.\n");
+ xc = xc_interface_open(NULL, NULL, 0);
+ if ( !xc ) {
+ fprintf(stderr, "failed to open xen control interface.\n");
+ return -1;
+ }
+
+ for (cpu = 0;; cpu++) {
+ uint64_t size, start;
+ int ret;
+
+ ret = xc_kexec_get_range(xc, KEXEC_RANGE_MA_CPU, cpu, &size, &start);
+ if (ret < 0)
+ break;
+
+ xen_phys_notes = realloc(xen_phys_notes,
+ sizeof(*xen_phys_notes) * (cpu + 1));
+ if (xen_phys_notes == NULL)
return -1;
- }
- memset(xen_phys_notes, 0, n);
- kexec_iomem_for_each_line(match,
- xen_crash_note_callback, NULL);
- xen_phys_cpus = cpus;
+
+ xen_phys_notes[cpu].base = start;
+ xen_phys_notes[cpu].length = size;
}
- return cpus;
+ xc_interface_close(xc);
+
+ xen_phys_cpus = cpu;
+
+ return cpu;
}
+#else
+int xen_get_nr_phys_cpus(void)
+{
+ return -1;
+}
+#endif
+
int xen_get_note(int cpu, uint64_t *addr, uint64_t *len)
{
--
1.7.2.5
Don Slutz
2013-Feb-26 13:53 UTC
Re: [PATCH 3/4] kexec/xen: use libxc to get location of crash notes
On 02/21/13 12:57, David Vrabel wrote:> From: David Vrabel <david.vrabel@citrix.com> > > Use xc_kexec_get_range(KEXEC_RANGE_MA_CPU) instead of parsing > /proc/iomem (which is only populated by non-upstream ("classic") Xen > kernels). > > Signed-off-by: David Vrabel <david.vrabel@citrix.com> > --- > kexec/crashdump-xen.c | 61 ++++++++++++++++++++++++++++--------------------- > 1 files changed, 35 insertions(+), 26 deletions(-) > > diff --git a/kexec/crashdump-xen.c b/kexec/crashdump-xen.c > index ff4706c..13335a5 100644 > --- a/kexec/crashdump-xen.c > +++ b/kexec/crashdump-xen.c > @@ -163,42 +163,51 @@ unsigned long xen_architecture(struct crash_elf_info *elf_info) > return machine; > } > > -static int xen_crash_note_callback(void *UNUSED(data), int nr, > - char *UNUSED(str), > - unsigned long base, > - unsigned long length) > -{ > - struct crash_note_info *note = xen_phys_notes + nr; > - > - note->base = base; > - note->length = length; > - > - return 0; > -} > - > +#ifdef HAVE_LIBXENCTRL > int xen_get_nr_phys_cpus(void) > { > - char *match = "Crash note\n"; > - int cpus, n; > + xc_interface *xc; > + int cpu; > > if (xen_phys_cpus) > return xen_phys_cpus; > > - if ((cpus = kexec_iomem_for_each_line(match, NULL, NULL))) { > - n = sizeof(struct crash_note_info) * cpus; > - xen_phys_notes = malloc(n); > - if (!xen_phys_notes) { > - fprintf(stderr, "failed to allocate xen_phys_notes.\n"); > + xc = xc_interface_open(NULL, NULL, 0); > + if ( !xc ) { > + fprintf(stderr, "failed to open xen control interface.\n"); > + return -1; > + } > + > + for (cpu = 0;; cpu++) {This code does work. Not sure why you did not use xc_physinfo() to get the number of cpus that there is data for and remove the need for calling realloc.> + uint64_t size, start; > + int ret; > + > + ret = xc_kexec_get_range(xc, KEXEC_RANGE_MA_CPU, cpu, &size, &start); > + if (ret < 0) > + break; > + > + xen_phys_notes = realloc(xen_phys_notes, > + sizeof(*xen_phys_notes) * (cpu + 1)); > + if (xen_phys_notes == NULL) > return -1; > - } > - memset(xen_phys_notes, 0, n); > - kexec_iomem_for_each_line(match, > - xen_crash_note_callback, NULL); > - xen_phys_cpus = cpus; > + > + xen_phys_notes[cpu].base = start; > + xen_phys_notes[cpu].length = size; > } > > - return cpus; > + xc_interface_close(xc); > + > + xen_phys_cpus = cpu; > + > + return cpu; > } > +#else > +int xen_get_nr_phys_cpus(void) > +{ > + return -1; > +} > +#endif > + > > int xen_get_note(int cpu, uint64_t *addr, uint64_t *len) > {-Don Slutz