The patch titled
x86_64 irq: Simplify the vector allocator
has been removed from the -mm tree. Its filename was
x86_64-irq-simplify-the-vector-allocator.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
Subject: x86_64 irq: Simplify the vector allocator
From: Eric W. Biederman <ebiederm@xxxxxxxxxxxx>
There is no reason to remember a per cpu position of which vector to try.
Keeping a global position is simpler and more likely to result in a global
vector allocation even if I don't need or require it. For level triggered
interrupts this means we are less likely to acknowledge another cpus irq,
and cause the level triggered irq to harmlessly refire.
This simplification makes it easier to only access data structures of
online cpus, by having fewer special cases to deal with.
Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx>
Acked-by: Yinghai Lu <yinghai.lu@xxxxxxx>
Acked-by: Muli Ben-Yehuda <muli@xxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
arch/x86_64/kernel/io_apic.c | 20 +++++++-------------
1 file changed, 7 insertions(+), 13 deletions(-)
diff -puN arch/x86_64/kernel/io_apic.c~x86_64-irq-simplify-the-vector-allocator arch/x86_64/kernel/io_apic.c
--- a/arch/x86_64/kernel/io_apic.c~x86_64-irq-simplify-the-vector-allocator
+++ a/arch/x86_64/kernel/io_apic.c
@@ -612,10 +612,7 @@ static int __assign_irq_vector(int irq,
* Also, we've got to be careful not to trash gate
* 0x80, because int 0x80 is hm, kind of importantish. ;)
*/
- static struct {
- int vector;
- int offset;
- } pos[NR_CPUS] = { [ 0 ... NR_CPUS - 1] = {FIRST_DEVICE_VECTOR, 0} };
+ static int current_vector = FIRST_DEVICE_VECTOR, current_offset = 0;
int old_vector = -1;
int cpu;
@@ -631,14 +628,13 @@ static int __assign_irq_vector(int irq,
for_each_cpu_mask(cpu, mask) {
cpumask_t domain;
- int first, new_cpu;
+ int new_cpu;
int vector, offset;
domain = vector_allocation_domain(cpu);
- first = first_cpu(domain);
- vector = pos[first].vector;
- offset = pos[first].offset;
+ vector = current_vector;
+ offset = current_offset;
next:
vector += 8;
if (vector >= FIRST_SYSTEM_VECTOR) {
@@ -646,7 +642,7 @@ next:
offset = (offset + 1) % 8;
vector = FIRST_DEVICE_VECTOR + offset;
}
- if (unlikely(pos[first].vector == vector))
+ if (unlikely(current_vector == vector))
continue;
if (vector == IA32_SYSCALL_VECTOR)
goto next;
@@ -654,10 +650,8 @@ next:
if (per_cpu(vector_irq, new_cpu)[vector] != -1)
goto next;
/* Found one! */
- for_each_cpu_mask(new_cpu, domain) {
- pos[new_cpu].vector = vector;
- pos[new_cpu].offset = offset;
- }
+ current_vector = vector;
+ current_offset = offset;
if (old_vector >= 0) {
int old_cpu;
for_each_cpu_mask(old_cpu, irq_domain[irq])
_
Patches currently in -mm which might be from ebiederm@xxxxxxxxxxxx are
origin.patch
improve-the-remove-sysctl-warnings.patch
sysctl-allow-a-zero-ctl_name-in-the-middle-of-a-sysctl-table.patch
sysctl-implement-ctl_unnumbered.patch
add-process_session-helper-routine.patch
rename-struct-namespace-to-struct-mnt_namespace.patch
add-an-identifier-to-nsproxy.patch
rename-struct-pspace-to-struct-pid_namespace.patch
add-pid_namespace-to-nsproxy.patch
use-current-nsproxy-pid_ns.patch
add-child-reaper-to-pid_namespace.patch
rename-struct-namespace-to-struct-mnt_namespace-cachefiles.patch
pidhash-temporary-debug-checks.patch
-
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