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Re: [PATCH v2] Enable tunables by default
On 16/06/2017 13:12, Szabolcs Nagy wrote:
> On 14/06/17 19:08, Siddhesh Poyarekar wrote:
>> All of the major architectures are adopting tunables as a way to add
>> tuning to the library, from hwcap_mask for aarch64 to HLE for s390 and
>> ifunc and cache geometry for x86. Given this adoption and the fact
>> that we don't want additional tuning knobs to be added outside of
>> tunables, it makes sense to enable tunables by default using this
>> trivial patch.
>>
>> Smoke tested on x86 to ensure that tunables code was built without
>> specifying it as a configure flag. I have kept it as --enabled and
>> not changed it to --disable since we want to still keep the option of
>> different kinds of front-ends for tunables.
>>
>> * configure.ac(--enable-tunables): Enable by default.
>> * configure: Regenerate.
>> * NEWS: Mention change.
>> * manual/install.texi (enable-tunables): Adjust documentation.
>> * INSTALL: Regenerate.
>
> note that gen-tunables.awk does not work with gawk 3.1.8
> because it uses multi-dimensional arrays
>
> so this broke the build for me on x86.
>
This patch below seems to work on gawk 3.1.8. It changes the order or the
elements in tunable_id_t and tunable_list, but as long both order match
I think it should work.
diff --git a/scripts/gen-tunables.awk b/scripts/gen-tunables.awk
index 93e5aff..ccdd0c6 100644
--- a/scripts/gen-tunables.awk
+++ b/scripts/gen-tunables.awk
@@ -39,20 +39,20 @@ $2 == "{" {
$1 == "}" {
if (tunable != "") {
# Tunables definition ended, now fill in default attributes.
- if (!types[top_ns][ns][tunable]) {
- types[top_ns][ns][tunable] = "STRING"
+ if (!types[top_ns,ns,tunable]) {
+ types[top_ns,ns,tunable] = "STRING"
}
- if (!minvals[top_ns][ns][tunable]) {
- minvals[top_ns][ns][tunable] = "0"
+ if (!minvals[top_ns,ns,tunable]) {
+ minvals[top_ns,ns,tunable] = "0"
}
- if (!maxvals[top_ns][ns][tunable]) {
- maxvals[top_ns][ns][tunable] = "0"
+ if (!maxvals[top_ns,ns,tunable]) {
+ maxvals[top_ns,ns,tunable] = "0"
}
- if (!env_alias[top_ns][ns][tunable]) {
- env_alias[top_ns][ns][tunable] = "NULL"
+ if (!env_alias[top_ns,ns,tunable]) {
+ env_alias[top_ns,ns,tunable] = "NULL"
}
- if (!security_level[top_ns][ns][tunable]) {
- security_level[top_ns][ns][tunable] = "SXID_ERASE"
+ if (!security_level[top_ns,ns,tunable]) {
+ security_level[top_ns,ns,tunable] = "SXID_ERASE"
}
tunable = ""
@@ -81,7 +81,7 @@ $1 == "}" {
if (tunable == "") {
# We encountered a tunable without any attributes, so note it with a
# default.
- types[top_ns][ns][$1] = "STRING"
+ types[top_ns,ns,$1] = "STRING"
next
}
@@ -91,20 +91,20 @@ $1 == "}" {
val = gensub(/^[ \t]+|[ \t]+$/, "", "g", arr[2])
if (attr == "type") {
- types[top_ns][ns][tunable] = val
+ types[top_ns,ns,tunable] = val
}
else if (attr == "minval") {
- minvals[top_ns][ns][tunable] = val
+ minvals[top_ns,ns,tunable] = val
}
else if (attr == "maxval") {
- maxvals[top_ns][ns][tunable] = val
+ maxvals[top_ns,ns,tunable] = val
}
else if (attr == "env_alias") {
- env_alias[top_ns][ns][tunable] = sprintf("\"%s\"", val)
+ env_alias[top_ns,ns,tunable] = sprintf("\"%s\"", val)
}
else if (attr == "security_level") {
if (val == "SXID_ERASE" || val == "SXID_IGNORE" || val == "NONE") {
- security_level[top_ns][ns][tunable] = val
+ security_level[top_ns,ns,tunable] = val
}
else {
printf("Line %d: Invalid value (%s) for security_level: %s, ", NR, val,
@@ -114,11 +114,11 @@ $1 == "}" {
}
}
else if (attr == "default") {
- if (types[top_ns][ns][tunable] == "STRING") {
- default_val[top_ns][ns][tunable] = sprintf(".strval = \"%s\"", val);
+ if (types[top_ns,ns,tunable] == "STRING") {
+ default_val[top_ns,ns,tunable] = sprintf(".strval = \"%s\"", val);
}
else {
- default_val[top_ns][ns][tunable] = sprintf(".numval = %s", val)
+ default_val[top_ns,ns,tunable] = sprintf(".numval = %s", val)
}
}
}
@@ -139,27 +139,27 @@ END {
# Now, the enum names
print "\ntypedef enum"
print "{"
- for (t in types) {
- for (n in types[t]) {
- for (m in types[t][n]) {
- printf (" TUNABLE_ENUM_NAME(%s, %s, %s),\n", t, n, m);
- }
- }
+ for (tnm in types) {
+ split (tnm, indices, SUBSEP);
+ t = indices[1];
+ n = indices[2];
+ m = indices[3];
+ printf (" TUNABLE_ENUM_NAME(%s, %s, %s),\n", t, n, m);
}
print "} tunable_id_t;\n"
# Finally, the tunable list.
print "\n#ifdef TUNABLES_INTERNAL"
print "static tunable_t tunable_list[] attribute_relro = {"
- for (t in types) {
- for (n in types[t]) {
- for (m in types[t][n]) {
- printf (" {TUNABLE_NAME_S(%s, %s, %s)", t, n, m)
- printf (", {TUNABLE_TYPE_%s, %s, %s}, {%s}, NULL, TUNABLE_SECLEVEL_%s, %s},\n",
- types[t][n][m], minvals[t][n][m], maxvals[t][n][m],
- default_val[t][n][m], security_level[t][n][m], env_alias[t][n][m]);
- }
- }
+ for (tnm in types) {
+ split (tnm, indices, SUBSEP);
+ t = indices[1];
+ n = indices[2];
+ m = indices[3];
+ printf (" {TUNABLE_NAME_S(%s, %s, %s)", t, n, m)
+ printf (", {TUNABLE_TYPE_%s, %s, %s}, {%s}, NULL, TUNABLE_SECLEVEL_%s, %s},\n",
+ types[t,n,m], minvals[t,n,m], maxvals[t,n,m],
+ default_val[t,n,m], security_level[t,n,m], env_alias[t,n,m]);
}
print "};"
print "#endif"