[PATCH v3 4/6] powerpc/nohash: Remove DEBUG_MAP_CONSISTENCY

From: Christophe Leroy
Date: Thu Jun 03 2021 - 05:29:13 EST


mmu_context handling has been there for years, so we
would know if there was problems with maps.

DEBUG_MAP_CONSISTENCY is not user selectable, remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
arch/powerpc/mm/nohash/mmu_context.c | 47 +---------------------------
1 file changed, 1 insertion(+), 46 deletions(-)

diff --git a/arch/powerpc/mm/nohash/mmu_context.c b/arch/powerpc/mm/nohash/mmu_context.c
index 437940d191d6..78369580b9ff 100644
--- a/arch/powerpc/mm/nohash/mmu_context.c
+++ b/arch/powerpc/mm/nohash/mmu_context.c
@@ -21,7 +21,6 @@
* also clear mm->cpu_vm_mask bits when processes are migrated
*/

-//#define DEBUG_MAP_CONSISTENCY
//#define DEBUG_CLAMP_LAST_CONTEXT 31
//#define DEBUG_HARDER

@@ -180,9 +179,6 @@ static unsigned int steal_all_contexts(void)
if (id != FIRST_CONTEXT) {
context_mm[id] = NULL;
__clear_bit(id, context_map);
-#ifdef DEBUG_MAP_CONSISTENCY
- mm->context.active = 0;
-#endif
}
if (IS_ENABLED(CONFIG_SMP))
__clear_bit(id, stale_map[cpu]);
@@ -224,37 +220,6 @@ static unsigned int steal_context_up(unsigned int id)
return id;
}

-#ifdef DEBUG_MAP_CONSISTENCY
-static void context_check_map(void)
-{
- unsigned int id, nrf, nact;
-
- nrf = nact = 0;
- for (id = FIRST_CONTEXT; id <= LAST_CONTEXT; id++) {
- int used = test_bit(id, context_map);
- if (!used)
- nrf++;
- if (used != (context_mm[id] != NULL))
- pr_err("MMU: Context %d is %s and MM is %p !\n",
- id, used ? "used" : "free", context_mm[id]);
- if (context_mm[id] != NULL)
- nact += context_mm[id]->context.active;
- }
- if (nrf != nr_free_contexts) {
- pr_err("MMU: Free context count out of sync ! (%d vs %d)\n",
- nr_free_contexts, nrf);
- nr_free_contexts = nrf;
- }
- if (nact > num_online_cpus())
- pr_err("MMU: More active contexts than CPUs ! (%d vs %d)\n",
- nact, num_online_cpus());
- if (FIRST_CONTEXT > 0 && !test_bit(0, context_map))
- pr_err("MMU: Context 0 has been freed !!!\n");
-}
-#else
-static void context_check_map(void) { }
-#endif
-
static void set_context(unsigned long id, pgd_t *pgd)
{
if (IS_ENABLED(CONFIG_PPC_8xx)) {
@@ -306,14 +271,8 @@ void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,

/* If we already have a valid assigned context, skip all that */
id = next->context.id;
- if (likely(id != MMU_NO_CONTEXT)) {
-#ifdef DEBUG_MAP_CONSISTENCY
- if (context_mm[id] != next)
- pr_err("MMU: mm 0x%p has id %d but context_mm[%d] says 0x%p\n",
- next, id, id, context_mm[id]);
-#endif
+ if (likely(id != MMU_NO_CONTEXT))
goto ctxt_ok;
- }

/* We really don't have a context, let's try to acquire one */
id = next_context;
@@ -349,7 +308,6 @@ void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
next->context.id = id;
pr_hardcont(" | new id=%d,nrf=%d", id, nr_free_contexts);

- context_check_map();
ctxt_ok:

/* If that context got marked stale on this CPU, then flush the
@@ -418,9 +376,6 @@ void destroy_context(struct mm_struct *mm)
if (id != MMU_NO_CONTEXT) {
__clear_bit(id, context_map);
mm->context.id = MMU_NO_CONTEXT;
-#ifdef DEBUG_MAP_CONSISTENCY
- mm->context.active = 0;
-#endif
context_mm[id] = NULL;
nr_free_contexts++;
}
--
2.25.0