Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-12-31 23:31:29 +00:00
Code Issues Packages Projects Releases Wiki Activity

powerpc/mm: constify FIRST_CONTEXT in mmu_context_nohash

Browse Source 
First context is now 1 for all supported platforms, so it
can be made a constant.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Christophe Leroy 2018-03-21 15:07:47 +01:00 committed by Michael Ellerman
parent 9887334b80
commit 8820a44738
1 changed files with 18 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
arch/powerpc/mm/mmu_context_nohash.c
View File

@ -54,7 +54,9 @@
#include "mmu_decl.h"
static unsigned int first_context, last_context;
#define FIRST_CONTEXT 1
static unsigned int last_context;
static unsigned int next_context, nr_free_contexts;
static unsigned long *context_map;
static unsigned long *stale_map[NR_CPUS];
@ -87,7 +89,7 @@ static unsigned int steal_context_smp(unsigned int id)
struct mm_struct *mm;
unsigned int cpu, max, i;
max = last_context - first_context;
max = last_context - FIRST_CONTEXT;
/* Attempt to free next_context first and then loop until we manage */
while (max--) {
@ -100,7 +102,7 @@ static unsigned int steal_context_smp(unsigned int id)
if (mm->context.active) {
id++;
if (id > last_context)
id = first_context;
id = FIRST_CONTEXT;
continue;
}
pr_hardcont(" | steal %d from 0x%p", id, mm);
@ -142,7 +144,7 @@ static unsigned int steal_all_contexts(void)
int cpu = smp_processor_id();
unsigned int id;
for (id = first_context; id <= last_context; id++) {
for (id = FIRST_CONTEXT; id <= last_context; id++) {
/* Pick up the victim mm */
mm = context_mm[id];
@ -150,7 +152,7 @@ static unsigned int steal_all_contexts(void)
/* Mark this mm as having no context anymore */
mm->context.id = MMU_NO_CONTEXT;
if (id != first_context) {
if (id != FIRST_CONTEXT) {
context_mm[id] = NULL;
__clear_bit(id, context_map);
#ifdef DEBUG_MAP_CONSISTENCY
@ -163,9 +165,9 @@ static unsigned int steal_all_contexts(void)
/* Flush the TLB for all contexts (not to be used on SMP) */
_tlbil_all();
nr_free_contexts = last_context - first_context;
nr_free_contexts = last_context - FIRST_CONTEXT;
return first_context;
return FIRST_CONTEXT;
}
/* Note that this will also be called on SMP if all other CPUs are
@ -201,7 +203,7 @@ static void context_check_map(void)
unsigned int id, nrf, nact;
nrf = nact = 0;
for (id = first_context; id <= last_context; id++) {
for (id = FIRST_CONTEXT; id <= last_context; id++) {
int used = test_bit(id, context_map);
if (!used)
nrf++;
@ -219,7 +221,7 @@ static void context_check_map(void)
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))
if (FIRST_CONTEXT > 0 && !test_bit(0, context_map))
pr_err("MMU: Context 0 has been freed !!!\n");
}
#else
@ -264,7 +266,7 @@ void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
/* We really don't have a context, let's try to acquire one */
id = next_context;
if (id > last_context)
id = first_context;
id = FIRST_CONTEXT;
map = context_map;
/* No more free contexts, let's try to steal one */
@ -289,7 +291,7 @@ void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next,
while (__test_and_set_bit(id, map)) {
id = find_next_zero_bit(map, last_context+1, id);
if (id > last_context)
id = first_context;
id = FIRST_CONTEXT;
}
stolen:
next_context = id + 1;
@ -439,15 +441,12 @@ void __init mmu_context_init(void)
* -- BenH
*/
if (mmu_has_feature(MMU_FTR_TYPE_8xx)) {
first_context = 1;
last_context = 16;
no_selective_tlbil = true;
} else if (mmu_has_feature(MMU_FTR_TYPE_47x)) {
first_context = 1;
last_context = 65535;
no_selective_tlbil = false;
} else {
first_context = 1;
last_context = 255;
no_selective_tlbil = false;
}
@ -473,16 +472,16 @@ void __init mmu_context_init(void)
printk(KERN_INFO
"MMU: Allocated %zu bytes of context maps for %d contexts\n",
2 * CTX_MAP_SIZE + (sizeof(void *) * (last_context + 1)),
last_context - first_context + 1);
last_context - FIRST_CONTEXT + 1);
/*
* Some processors have too few contexts to reserve one for
* init_mm, and require using context 0 for a normal task.
* Other processors reserve the use of context zero for the kernel.
* This code assumes first_context < 32.
* This code assumes FIRST_CONTEXT < 32.
*/
context_map[0] = (1 << first_context) - 1;
next_context = first_context;
nr_free_contexts = last_context - first_context + 1;
context_map[0] = (1 << FIRST_CONTEXT) - 1;
next_context = FIRST_CONTEXT;
nr_free_contexts = last_context - FIRST_CONTEXT + 1;
}