[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [PATCH v2 02/16] xl: allow for node-wise specification of vcpu pinning
On 13/11/13 19:11, Dario Faggioli wrote: Making it possible to use something like the following: * "nodes:0-3": all pCPUs of nodes 0,1,2,3; * "nodes:0-3,^node:2": all pCPUS of nodes 0,1,3; * "1,nodes:1-2,^6": pCPU 1 plus all pCPUs of nodes 1,2 but not pCPU 6; * ... In both domain config file and `xl vcpu-pin'. Signed-off-by: Dario Faggioli <dario.faggioli@xxxxxxxxxx> Reviewed-by: George Dunlap <george.dunlap@xxxxxxxxxxxxx> --- Changes from v1 (of this very series): * actually checking for both "nodes:" and "node:" as per the doc says; * using strcmp() (rather than strncmp()) when matching "all", to avoid returning success on any longer string that just begins with "all"; * fixing the handling (well, the rejection, actually) of "^all" and "^nodes:all"; * make some string pointers const. Changes from v2 (of original series): * turned a 'return' into 'goto out', consistently with the most of exit patterns; * harmonized error handling: now parse_range() return a libxl error code, as requested during review; * dealing with "all" moved inside update_cpumap_range(). It's tricky to move it in parse_range() (as requested during review), since we need the cpumap being modified handy when dealing with it. However, having it in update_cpumap_range() simplifies the code just as much as that; * explicitly checking for junk after a valid value or range in parse_range(), as requested during review; * xl exits on parsing failing, so no need to reset the cpumap to something sensible in vcpupin_parse(), as suggested during review; Changes from v1 (of original series): * code rearranged in order to look more simple to follow and understand, as requested during review; * improved docs in xl.cfg.pod.5, as requested during review; * strtoul() now returns into unsigned long, and the case where it returns ULONG_MAX is now taken into account, as requested during review; * stuff like "all,^7" now works, as requested during review. Specifying just "^7" does not work either before or after this change * killed some magic (i.e., `ptr += 5 + (ptr[4] == 's'`) by introducing STR_SKIP_PREFIX() macro, as requested during review. --- docs/man/xl.cfg.pod.5 | 20 ++++++ tools/libxl/xl_cmdimpl.c | 153 +++++++++++++++++++++++++++++++++------------- 2 files changed, 128 insertions(+), 45 deletions(-) diff --git a/docs/man/xl.cfg.pod.5 b/docs/man/xl.cfg.pod.5 index e6fc83f..5dbc73c 100644 --- a/docs/man/xl.cfg.pod.5 +++ b/docs/man/xl.cfg.pod.5 @@ -115,7 +115,25 @@ To allow all the vcpus of the guest to run on all the cpus on the host.=item "0-3,5,^1" -To allow all the vcpus of the guest to run on cpus 0,2,3,5.+To allow all the vcpus of the guest to run on cpus 0,2,3,5. Combining +this with "all" is possible, meaning "all,^7" results in all the vcpus +of the guest running on all the cpus on the host except cpu 7. + +=item "nodes:0-3,node:^2" + +To allow all the vcpus of the guest to run on the cpus from NUMA nodes +0,1,3 of the host. So, if cpus 0-3 belongs to node 0, cpus 4-7 belongs +to node 1 and cpus 8-11 to node 3, the above would mean all the vcpus +of the guest will run on cpus 0-3,8-11. + +Combining this notation with the one above is possible. For instance, +"1,node:2,^6", means all the vcpus of the guest will run on cpu 1 and +on all the cpus of NUMA node 2, but not on cpu 6. Following the same +example as above, that would be cpus 1,4,5,7. + +Combining this with "all" is also possible, meaning "all,^nodes:1" +results in all the vcpus of the guest running on all the cpus on the +host, except for the cpus belonging to the host NUMA node 1.=item ["2", "3"] (or [2, 3]) diff --git a/tools/libxl/xl_cmdimpl.c b/tools/libxl/xl_cmdimpl.cindex 13e97b3..5f5cc43 100644 --- a/tools/libxl/xl_cmdimpl.c +++ b/tools/libxl/xl_cmdimpl.c @@ -59,6 +59,11 @@ } \ })+#define STR_HAS_PREFIX( a, b ) \+ ( strncmp(a, b, strlen(b)) == 0 ) +#define STR_SKIP_PREFIX( a, b ) \ + ( STR_HAS_PREFIX(a, b) ? ((a) += strlen(b), 1) : 0 ) +int logfile = 2; @@ -513,61 +518,121 @@ static void split_string_into_string_list(const char *str,free(s); }-static int vcpupin_parse(char *cpu, libxl_bitmap *cpumap)+static int parse_range(const char *str, unsigned long *a, unsigned long *b) { - libxl_bitmap exclude_cpumap; - uint32_t cpuida, cpuidb; - char *endptr, *toka, *tokb, *saveptr = NULL; - int i, rc = 0, rmcpu; + const char *nstr; + char *endptr;- if (!strcmp(cpu, "all")) {- libxl_bitmap_set_any(cpumap); - return 0; + *a = *b = strtoul(str, &endptr, 10); + if (endptr == str || *a == ULONG_MAX) + return ERROR_INVAL; + + if (*endptr == '-') { + nstr = endptr + 1; + + *b = strtoul(nstr, &endptr, 10); + if (endptr == nstr || *b == ULONG_MAX || *b < *a) + return ERROR_INVAL; + } + + /* Valid value or range so far, but we also don't want junk after that */ + if (*endptr != '\0') + return ERROR_INVAL; + + return 0; +} + +/* + * Add or removes a specific set of cpus (specified in str, either as + * single cpus or as entire NUMA nodes) to/from cpumap. + */ +static int update_cpumap_range(const char *str, libxl_bitmap *cpumap) +{ + unsigned long ida, idb; + libxl_bitmap node_cpumap; + bool is_not = false, is_nodes = false; + int rc = 0; + + libxl_bitmap_init(&node_cpumap); + + rc = libxl_node_bitmap_alloc(ctx, &node_cpumap, 0); + if (rc) { + fprintf(stderr, "libxl_node_bitmap_alloc failed.\n"); + goto out; }- if (libxl_cpu_bitmap_alloc(ctx, &exclude_cpumap, 0)) {- fprintf(stderr, "Error: Failed to allocate cpumap.\n"); - return ENOMEM; + /* Are we adding or removing cpus/nodes? */ + if (STR_SKIP_PREFIX(str, "^")) { + is_not = true; }- for (toka = strtok_r(cpu, ",", &saveptr); toka;- toka = strtok_r(NULL, ",", &saveptr)) { - rmcpu = 0; - if (*toka == '^') { - /* This (These) Cpu(s) will be removed from the map */ - toka++; - rmcpu = 1; - } - /* Extract a valid (range of) cpu(s) */ - cpuida = cpuidb = strtoul(toka, &endptr, 10); - if (endptr == toka) { - fprintf(stderr, "Error: Invalid argument.\n"); - rc = EINVAL; - goto vcpp_out; - } - if (*endptr == '-') { - tokb = endptr + 1; - cpuidb = strtoul(tokb, &endptr, 10); - if (endptr == tokb || cpuida > cpuidb) { - fprintf(stderr, "Error: Invalid argument.\n"); - rc = EINVAL; - goto vcpp_out; + /* Are we dealing with cpus or full nodes? */ + if (STR_SKIP_PREFIX(str, "node:") || STR_SKIP_PREFIX(str, "nodes:")) { + is_nodes = true; + } + + if (strcmp(str, "all") == 0) { + /* We do not accept "^all" or "^nodes:all" */ + if (is_not) { + fprintf(stderr, "Can't combine \"^\" and \"all\".\n"); + rc = ERROR_INVAL; + } else + libxl_bitmap_set_any(cpumap); + goto out; + } + + rc = parse_range(str, &ida, &idb); + if (rc) { + fprintf(stderr, "Invalid pcpu range: %s.\n", str); + goto out; + } + + /* Add or remove the specified cpus in the range */ + while (ida <= idb) { + if (is_nodes) { + /* Add/Remove all the cpus of a NUMA node */ + int i; + + rc = libxl_node_to_cpumap(ctx, ida, &node_cpumap); + if (rc) { + fprintf(stderr, "libxl_node_to_cpumap failed.\n"); + goto out; } + + /* Add/Remove all the cpus in the node cpumap */ + libxl_for_each_set_bit(i, node_cpumap) { + is_not ? libxl_bitmap_reset(cpumap, i) : + libxl_bitmap_set(cpumap, i); + } + } else { + /* Add/Remove this cpu */ + is_not ? libxl_bitmap_reset(cpumap, ida) : + libxl_bitmap_set(cpumap, ida); } - while (cpuida <= cpuidb) { - rmcpu == 0 ? libxl_bitmap_set(cpumap, cpuida) : - libxl_bitmap_set(&exclude_cpumap, cpuida); - cpuida++; - } + ida++; }- /* Clear all the cpus from the removal list */- libxl_for_each_set_bit(i, exclude_cpumap) { - libxl_bitmap_reset(cpumap, i); - } + out: + libxl_bitmap_dispose(&node_cpumap); + return rc; +}-vcpp_out:- libxl_bitmap_dispose(&exclude_cpumap); +/* + * Takes a string representing a set of cpus (specified either as + * single cpus or as eintire NUMA nodes) and turns it into the + * corresponding libxl_bitmap (in cpumap). + */ +static int vcpupin_parse(char *cpu, libxl_bitmap *cpumap) +{ + char *ptr, *saveptr = NULL; + int rc = 0; + + for (ptr = strtok_r(cpu, ",", &saveptr); ptr; + ptr = strtok_r(NULL, ",", &saveptr)) { + rc = update_cpumap_range(ptr, cpumap); + if (rc) + break; + }return rc;} _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx http://lists.xen.org/xen-devel
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |