diff options
| author | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2022-06-17 13:25:15 +0100 |
|---|---|---|
| committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2024-01-08 12:33:02 +0000 |
| commit | 4c888ada40d97fe926ced7a8adcad36533f404be (patch) | |
| tree | a379dd3dd1936bba8189a48f5d208ea8af5ab05a /arch/arm64/mm/ktext.c | |
| parent | 6f9c4de225ec7830b9529eea0d14a84295629408 (diff) | |
arm64: text replication: add test module
Add a module to allow kernel text replication to be tested; this
exposes some data in procfs which can be used to verify that:
(a) we're using different page tables in TTBR1 on CPUs in different
NUMA nodes
(b) that CPUs in different NUMA nodes are indeed accessing different
copies of the kernel
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'arch/arm64/mm/ktext.c')
| -rw-r--r-- | arch/arm64/mm/ktext.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/arm64/mm/ktext.c b/arch/arm64/mm/ktext.c index 4ab04f531c81..d29497c37da9 100644 --- a/arch/arm64/mm/ktext.c +++ b/arch/arm64/mm/ktext.c @@ -22,6 +22,11 @@ struct pgtables *pgtables[MAX_NUMNODES] = { static void *kernel_texts[MAX_NUMNODES]; +#if IS_ENABLED(CONFIG_TEST_KTEXT_REPLICATE) +const char ktext_nid[32] = "0"; +EXPORT_SYMBOL_GPL(ktext_nid); +#endif + static pgd_t *__swapper_pg_dir_node(int nid) { return pgtables[nid]->swapper_pg_dir; @@ -131,6 +136,9 @@ early_param("ktext", parse_ktext); void __init ktext_replication_init(void) { size_t size = __end_rodata - _stext; +#if IS_ENABLED(CONFIG_TEST_KTEXT_REPLICATE) + size_t kt_nid = ktext_nid - _stext; +#endif int kidx = pgd_index((phys_addr_t)KERNEL_START); int nid; @@ -159,6 +167,13 @@ void __init ktext_replication_init(void) /* Allocate and copy initial kernel text for this node */ kernel_texts[nid] = memblock_alloc_node(size, PAGE_SIZE, nid); memcpy(kernel_texts[nid], _stext, size); + +#if IS_ENABLED(CONFIG_TEST_KTEXT_REPLICATE) + /* Update the node ID in each copy of the kernel text/rodata */ + snprintf(kernel_texts[nid] + kt_nid, sizeof(kernel_texts[nid]), + "%u", nid); +#endif + caches_clean_inval_pou((u64)kernel_texts[nid], (u64)kernel_texts[nid] + size); |