[PATCH v2 6/7] arm64: capabilities: Use linear array for detection and verification

From: Suzuki K Poulose
Date: Fri Nov 30 2018 - 12:18:46 EST


Use the sorted list of capability entries for the detection and
verification.

Reviewed-by: Vladimiri Murzin <vladimir.murzin@xxxxxxx>
Tested-by: Vladimiri Murzin <vladimir.murzin@xxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
---
arch/arm64/kernel/cpufeature.c | 42 +++++++++++++++++-------------------------
1 file changed, 17 insertions(+), 25 deletions(-)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 618857f..13d729c 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -1512,28 +1512,25 @@ static void __init setup_elf_hwcaps(const struct arm64_cpu_capabilities *hwcaps)
cap_set_elf_hwcap(hwcaps);
}

-static void __update_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
- u16 scope_mask, const char *info)
+static void update_cpu_capabilities(u16 scope_mask)
{
+ int i;
+ const struct arm64_cpu_capabilities *caps;
+
scope_mask &= ARM64_CPUCAP_SCOPE_MASK;
- for (; caps->matches; caps++) {
- if (!(caps->type & scope_mask) ||
+ for (i = 0; i < ARM64_NCAPS; i++) {
+ caps = cpu_hwcaps_ptrs[i];
+ if (!caps || !(caps->type & scope_mask) ||
+ cpus_have_cap(caps->capability) ||
!caps->matches(caps, cpucap_default_scope(caps)))
continue;

- if (!cpus_have_cap(caps->capability) && caps->desc)
- pr_info("%s %s\n", info, caps->desc);
+ if (caps->desc)
+ pr_info("detected: %s\n", caps->desc);
cpus_set_cap(caps->capability);
}
}

-static void update_cpu_capabilities(u16 scope_mask)
-{
- __update_cpu_capabilities(arm64_errata, scope_mask,
- "enabling workaround for");
- __update_cpu_capabilities(arm64_features, scope_mask, "detected:");
-}
-
static int __enable_cpu_capability(void *arg)
{
const struct arm64_cpu_capabilities *cap = arg;
@@ -1597,16 +1594,17 @@ static void __init enable_cpu_capabilities(u16 scope_mask)
*
* Returns "false" on conflicts.
*/
-static bool
-__verify_local_cpu_caps(const struct arm64_cpu_capabilities *caps,
- u16 scope_mask)
+static bool verify_local_cpu_caps(u16 scope_mask)
{
+ int i;
bool cpu_has_cap, system_has_cap;
+ const struct arm64_cpu_capabilities *caps;

scope_mask &= ARM64_CPUCAP_SCOPE_MASK;

- for (; caps->matches; caps++) {
- if (!(caps->type & scope_mask))
+ for (i = 0; i < ARM64_NCAPS; i++) {
+ caps = cpu_hwcaps_ptrs[i];
+ if (!caps || !(caps->type & scope_mask))
continue;

cpu_has_cap = caps->matches(caps, SCOPE_LOCAL_CPU);
@@ -1637,7 +1635,7 @@ __verify_local_cpu_caps(const struct arm64_cpu_capabilities *caps,
}
}

- if (caps->matches) {
+ if (i < ARM64_NCAPS) {
pr_crit("CPU%d: Detected conflict for capability %d (%s), System: %d, CPU: %d\n",
smp_processor_id(), caps->capability,
caps->desc, system_has_cap, cpu_has_cap);
@@ -1647,12 +1645,6 @@ __verify_local_cpu_caps(const struct arm64_cpu_capabilities *caps,
return true;
}

-static bool verify_local_cpu_caps(u16 scope_mask)
-{
- return __verify_local_cpu_caps(arm64_errata, scope_mask) &&
- __verify_local_cpu_caps(arm64_features, scope_mask);
-}
-
/*
* Check for CPU features that are used in early boot
* based on the Boot CPU value.
--
2.7.4