summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDavid Hildenbrand <david@redhat.com>2020-08-06 23:25:38 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-08-07 11:33:29 -0700
commit839195352d8235072dcaac054b2e26b2dd2213e5 (patch)
tree343e61c2722e5adf12b05c1e62cd48ac11bc52bb
parent93146d98ce73fa416be3ffa147247a2454645ebc (diff)
mm/shuffle: remove dynamic reconfiguration
Commit e900a918b098 ("mm: shuffle initial free memory to improve memory-side-cache utilization") promised "autodetection of a memory-side-cache (to be added in a follow-on patch)" over a year ago. The original series included patches [1], however, they were dropped during review [2] to be followed-up later. Due to lack of platforms that publish an HMAT, autodetection is currently not implemented. However, manual activation is actively used [3]. Let's simplify for now and re-add when really (ever?) needed. [1] https://lkml.kernel.org/r/154510700291.1941238.817190985966612531.stgit@dwillia2-desk3.amr.corp.intel.com [2] https://lkml.kernel.org/r/154690326478.676627.103843791978176914.stgit@dwillia2-desk3.amr.corp.intel.com [3] https://lkml.kernel.org/r/CAPcyv4irwGUU2x+c6b4L=KbB1dnasNKaaZd6oSpYjL9kfsnROQ@mail.gmail.com Signed-off-by: David Hildenbrand <david@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Dan Williams <dan.j.williams@intel.com> Link: http://lkml.kernel.org/r/20200624094741.9918-4-david@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--mm/shuffle.c28
-rw-r--r--mm/shuffle.h17
2 files changed, 2 insertions, 43 deletions
diff --git a/mm/shuffle.c b/mm/shuffle.c
index dd13ab851b3e..9b5cd4b004b0 100644
--- a/mm/shuffle.c
+++ b/mm/shuffle.c
@@ -10,33 +10,11 @@
#include "shuffle.h"
DEFINE_STATIC_KEY_FALSE(page_alloc_shuffle_key);
-static unsigned long shuffle_state __ro_after_init;
-
-/*
- * Depending on the architecture, module parameter parsing may run
- * before, or after the cache detection. SHUFFLE_FORCE_DISABLE prevents,
- * or reverts the enabling of the shuffle implementation. SHUFFLE_ENABLE
- * attempts to turn on the implementation, but aborts if it finds
- * SHUFFLE_FORCE_DISABLE already set.
- */
-__meminit void page_alloc_shuffle(enum mm_shuffle_ctl ctl)
-{
- if (ctl == SHUFFLE_FORCE_DISABLE)
- set_bit(SHUFFLE_FORCE_DISABLE, &shuffle_state);
-
- if (test_bit(SHUFFLE_FORCE_DISABLE, &shuffle_state)) {
- if (test_and_clear_bit(SHUFFLE_ENABLE, &shuffle_state))
- static_branch_disable(&page_alloc_shuffle_key);
- } else if (ctl == SHUFFLE_ENABLE
- && !test_and_set_bit(SHUFFLE_ENABLE, &shuffle_state))
- static_branch_enable(&page_alloc_shuffle_key);
-}
static bool shuffle_param;
static int shuffle_show(char *buffer, const struct kernel_param *kp)
{
- return sprintf(buffer, "%c\n", test_bit(SHUFFLE_ENABLE, &shuffle_state)
- ? 'Y' : 'N');
+ return sprintf(buffer, "%c\n", shuffle_param ? 'Y' : 'N');
}
static __meminit int shuffle_store(const char *val,
@@ -47,9 +25,7 @@ static __meminit int shuffle_store(const char *val,
if (rc < 0)
return rc;
if (shuffle_param)
- page_alloc_shuffle(SHUFFLE_ENABLE);
- else
- page_alloc_shuffle(SHUFFLE_FORCE_DISABLE);
+ static_branch_enable(&page_alloc_shuffle_key);
return 0;
}
module_param_call(shuffle, shuffle_store, shuffle_show, &shuffle_param, 0400);
diff --git a/mm/shuffle.h b/mm/shuffle.h
index 4d79f03b6658..71b784f0b7c3 100644
--- a/mm/shuffle.h
+++ b/mm/shuffle.h
@@ -4,23 +4,10 @@
#define _MM_SHUFFLE_H
#include <linux/jump_label.h>
-/*
- * SHUFFLE_ENABLE is called from the command line enabling path, or by
- * platform-firmware enabling that indicates the presence of a
- * direct-mapped memory-side-cache. SHUFFLE_FORCE_DISABLE is called from
- * the command line path and overrides any previous or future
- * SHUFFLE_ENABLE.
- */
-enum mm_shuffle_ctl {
- SHUFFLE_ENABLE,
- SHUFFLE_FORCE_DISABLE,
-};
-
#define SHUFFLE_ORDER (MAX_ORDER-1)
#ifdef CONFIG_SHUFFLE_PAGE_ALLOCATOR
DECLARE_STATIC_KEY_FALSE(page_alloc_shuffle_key);
-extern void page_alloc_shuffle(enum mm_shuffle_ctl ctl);
extern void __shuffle_free_memory(pg_data_t *pgdat);
extern bool shuffle_pick_tail(void);
static inline void shuffle_free_memory(pg_data_t *pgdat)
@@ -58,10 +45,6 @@ static inline void shuffle_zone(struct zone *z)
{
}
-static inline void page_alloc_shuffle(enum mm_shuffle_ctl ctl)
-{
-}
-
static inline bool is_shuffle_order(int order)
{
return false;