[PATCH v6 8/8] add a new interface to show the memory usage of 1st kernel
Baoquan He
bhe at redhat.com
Sun Aug 31 20:15:40 PDT 2014
Recently people complained that they don't know how to decide how
much disk size need be reserved for kdump. E.g there are lots of
machines with different memory size, if the memory usage information
of current system can be shown, that can help them to make an estimate
how much storage space need be reserved.
In this patch, a new interface is added into makedumpfile. By the
help of this, people can know the page number of memory in different
use. The implementation is analyzing the "System Ram" and "kernel text"
program segment of /proc/kcore excluding the crashkernel range, then
calculating the page number of different kind per vmcoreinfo.
The print is like below:
~$ ./makedumpfile --mem-usage /proc/kcore
The kernel version is not supported.
The makedumpfile operation may be incomplete.
Excluding unnecessary pages : [100.0 %] |
----------------------------------------------------------------------
TYPE PAGES EXCLUDABLE DESCRIPTION
ZERO 28823 yes Pages filled with zero
CACHE 197932 yes Cache pages
CACHE_PRIVATE 15862 yes Cache pages + private
USER 30778 yes User process pages
FREE 3671105 yes Free pages
KERN_DATA 105168 no Dumpable kernel data
Total pages on system: 4049668
makedumpfile Completed.
BTW, in formal version of kernel which maintainer declares to support
after sufficient test, the warning message about kernel version won't
occur.
Signed-off-by: Baoquan He <bhe at redhat.com>
---
makedumpfile.8 | 17 ++++++++++++++
makedumpfile.c | 74 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
makedumpfile.h | 2 ++
print_info.c | 8 +++++++
4 files changed, 100 insertions(+), 1 deletion(-)
diff --git a/makedumpfile.8 b/makedumpfile.8
index 25fe74e..64abbc7 100644
--- a/makedumpfile.8
+++ b/makedumpfile.8
@@ -532,6 +532,23 @@ it is necessary to specfiy [\-x \fIVMLINUX\fR] or [\-i \fIVMCOREINFO\fR].
# makedumpfile \-\-dump-dmesg -x vmlinux /proc/vmcore dmesgfile
.br
+
+.TP
+\fB\-\-mem-usage\fR
+This option is used to show the page numbers of current system in different
+use. It should be executed in 1st kernel. By the help of this, user can know
+how many pages is dumpable when different dump_level is specified. It analyzes
+the 'System Ram' and 'kernel text' program segment of /proc/kcore excluding
+the crashkernel range, then calculates the page number of different kind per
+vmcoreinfo. So currently /proc/kcore need be specified explicitly.
+
+.br
+.B Example:
+.br
+# makedumpfile \-\-mem-usage /proc/kcore
+.br
+
+
.TP
\fB\-\-diskset=VMCORE\fR
Specify multiple \fIVMCORE\fRs created on sadump diskset configuration
diff --git a/makedumpfile.c b/makedumpfile.c
index c3d45de..a9d0e63 100644
--- a/makedumpfile.c
+++ b/makedumpfile.c
@@ -707,7 +707,7 @@ get_kernel_version(char *release)
if ((version < OLDEST_VERSION) || (LATEST_VERSION < version)) {
MSG("The kernel version is not supported.\n");
- MSG("The created dumpfile may be incomplete.\n");
+ MSG("The makedumpfile operation may be incomplete.\n");
}
return version;
@@ -9007,6 +9007,13 @@ check_param_for_creating_dumpfile(int argc, char *argv[])
*/
info->name_memory = argv[optind];
+ } else if ((argc == optind + 1) && info->flag_mem_usage) {
+ /*
+ * Parameter for showing the page number of memory
+ * in different use from.
+ */
+ info->name_memory = argv[optind];
+
} else
return FALSE;
@@ -9251,6 +9258,58 @@ static int get_sys_kernel_vmcoreinfo(uint64_t *addr, uint64_t *len)
return TRUE;
}
+int show_mem_usage(void)
+{
+ uint64_t vmcoreinfo_addr, vmcoreinfo_len;
+
+ if (!is_crashkernel_mem_reserved()) {
+ ERRMSG("No memory is reserved for crashkenrel!\n");
+ return FALSE;
+ }
+
+
+ if (!info->flag_cyclic)
+ info->flag_cyclic = TRUE;
+
+ info->dump_level = MAX_DUMP_LEVEL;
+
+ if (!get_page_offset())
+ return FALSE;
+
+ if (!open_dump_memory())
+ return FALSE;
+
+ if (!get_elf_loads(info->fd_memory, info->name_memory))
+ return FALSE;
+
+ if (!get_sys_kernel_vmcoreinfo(&vmcoreinfo_addr, &vmcoreinfo_len))
+ return FALSE;
+
+ if (!set_kcore_vmcoreinfo(vmcoreinfo_addr, vmcoreinfo_len))
+ return FALSE;
+
+ if (!get_kcore_dump_loads())
+ return FALSE;
+
+ if (!initial())
+ return FALSE;
+
+
+ if (!prepare_bitmap2_buffer_cyclic())
+ return FALSE;
+
+ info->num_dumpable = get_num_dumpable_cyclic();
+
+ free_bitmap2_buffer_cyclic();
+
+ print_mem_usage();
+
+ if (!close_files_for_creating_dumpfile())
+ return FALSE;
+
+ return TRUE;
+}
+
static struct option longopts[] = {
{"split", no_argument, NULL, OPT_SPLIT},
@@ -9268,6 +9327,7 @@ static struct option longopts[] = {
{"cyclic-buffer", required_argument, NULL, OPT_CYCLIC_BUFFER},
{"eppic", required_argument, NULL, OPT_EPPIC},
{"non-mmap", no_argument, NULL, OPT_NON_MMAP},
+ {"mem-usage", no_argument, NULL, OPT_MEM_USAGE},
{0, 0, 0, 0}
};
@@ -9359,6 +9419,9 @@ main(int argc, char *argv[])
case OPT_DUMP_DMESG:
info->flag_dmesg = 1;
break;
+ case OPT_MEM_USAGE:
+ info->flag_mem_usage = 1;
+ break;
case OPT_COMPRESS_SNAPPY:
info->flag_compress = DUMP_DH_COMPRESSED_SNAPPY;
break;
@@ -9499,6 +9562,15 @@ main(int argc, char *argv[])
MSG("\n");
MSG("The dmesg log is saved to %s.\n", info->name_dumpfile);
+ } else if (info->flag_mem_usage) {
+ if (!check_param_for_creating_dumpfile(argc, argv)) {
+ MSG("Commandline parameter is invalid.\n");
+ MSG("Try `makedumpfile --help' for more information.\n");
+ goto out;
+ }
+
+ if (!show_mem_usage())
+ goto out;
} else {
if (!check_param_for_creating_dumpfile(argc, argv)) {
MSG("Commandline parameter is invalid.\n");
diff --git a/makedumpfile.h b/makedumpfile.h
index e83bd95..6ee4cae 100644
--- a/makedumpfile.h
+++ b/makedumpfile.h
@@ -978,6 +978,7 @@ struct DumpInfo {
int flag_force; /* overwrite existing stuff */
int flag_exclude_xen_dom;/* exclude Domain-U from xen-kdump */
int flag_dmesg; /* dump the dmesg log out of the vmcore file */
+ int flag_mem_usage; /*show the page number of memory in different use*/
int flag_use_printk_log; /* did we read printk_log symbol name? */
int flag_nospace; /* the flag of "No space on device" error */
int flag_vmemmap; /* kernel supports vmemmap address space */
@@ -1867,6 +1868,7 @@ struct elf_prstatus {
#define OPT_CYCLIC_BUFFER OPT_START+11
#define OPT_EPPIC OPT_START+12
#define OPT_NON_MMAP OPT_START+13
+#define OPT_MEM_USAGE OPT_START+14
/*
* Function Prototype.
diff --git a/print_info.c b/print_info.c
index 7592690..29db918 100644
--- a/print_info.c
+++ b/print_info.c
@@ -264,6 +264,14 @@ print_usage(void)
MSG(" LOGFILE. If a VMCORE does not contain VMCOREINFO for dmesg, it is\n");
MSG(" necessary to specfiy [-x VMLINUX] or [-i VMCOREINFO].\n");
MSG("\n");
+ MSG(" [--mem-usage]:\n");
+ MSG(" This option is used to show the page numbers of current system in different\n");
+ MSG(" use. It should be executed in 1st kernel. By the help of this, user can know\n");
+ MSG(" how many pages is dumpable when different dump_level is specified. It analyzes\n");
+ MSG(" the 'System Ram' and 'kernel text' program segment of /proc/kcore excluding\n");
+ MSG(" the crashkernel range, then calculates the page number of different kind per\n");
+ MSG(" vmcoreinfo. So currently /proc/kcore need be specified explicitly.\n");
+ MSG("\n");
MSG(" [-D]:\n");
MSG(" Print debugging message.\n");
MSG("\n");
--
1.8.5.3
More information about the kexec
mailing list