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authorJames Morse <james.morse@arm.com>2024-02-13 18:44:24 +0000
committerBorislav Petkov (AMD) <bp@alien8.de>2024-02-16 19:18:32 +0100
commit6eac36bb9eb0349c983313c71692c19d50b56878 (patch)
tree2d705c77f295a28f2dfc85f336dcb9f5a9e9ce94 /arch/x86/kernel/cpu/resctrl/rdtgroup.c
parentx86/resctrl: Use __set_bit()/__clear_bit() instead of open coding (diff)
downloadwireguard-linux-6eac36bb9eb0349c983313c71692c19d50b56878.tar.xz
wireguard-linux-6eac36bb9eb0349c983313c71692c19d50b56878.zip
x86/resctrl: Allocate the cleanest CLOSID by searching closid_num_dirty_rmid
MPAM's PMG bits extend its PARTID space, meaning the same PMG value can be used for different control groups. This means once a CLOSID is allocated, all its monitoring ids may still be dirty, and held in limbo. Instead of allocating the first free CLOSID, on architectures where CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID is enabled, search closid_num_dirty_rmid[] to find the cleanest CLOSID. The CLOSID found is returned to closid_alloc() for the free list to be updated. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-11-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Diffstat (limited to '')
-rw-r--r--arch/x86/kernel/cpu/resctrl/rdtgroup.c19
1 files changed, 14 insertions, 5 deletions
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index bc6e0f83c847..8fc46204a6cc 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -137,13 +137,22 @@ static void closid_init(void)
static int closid_alloc(void)
{
- u32 closid = ffs(closid_free_map);
+ int cleanest_closid;
+ u32 closid;
lockdep_assert_held(&rdtgroup_mutex);
- if (closid == 0)
- return -ENOSPC;
- closid--;
+ if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) {
+ cleanest_closid = resctrl_find_cleanest_closid();
+ if (cleanest_closid < 0)
+ return cleanest_closid;
+ closid = cleanest_closid;
+ } else {
+ closid = ffs(closid_free_map);
+ if (closid == 0)
+ return -ENOSPC;
+ closid--;
+ }
__clear_bit(closid, &closid_free_map);
return closid;
@@ -163,7 +172,7 @@ void closid_free(int closid)
* Return: true if @closid is currently associated with a resource group,
* false if @closid is free
*/
-static bool closid_allocated(unsigned int closid)
+bool closid_allocated(unsigned int closid)
{
lockdep_assert_held(&rdtgroup_mutex);