The patch titled
percpu_counters-inline-the-percpu_counter_add_batch-fastpath-fix
has been added to the -mm tree. Its filename is
percpu_counters-inline-the-percpu_counter_add_batch-fastpath-fix.patch
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The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: percpu_counters-inline-the-percpu_counter_add_batch-fastpath-fix
From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
fix 32-bit overflows. Make things worse.
Cc: Christoph Lameter <cl@xxxxxxxxxxxxxxxxxxxx>
Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/percpu_counter.h | 9 +++++----
lib/percpu_counter.c | 8 +++++---
2 files changed, 10 insertions(+), 7 deletions(-)
diff -puN include/linux/percpu_counter.h~percpu_counters-inline-the-percpu_counter_add_batch-fastpath-fix include/linux/percpu_counter.h
--- a/include/linux/percpu_counter.h~percpu_counters-inline-the-percpu_counter_add_batch-fastpath-fix
+++ a/include/linux/percpu_counter.h
@@ -43,7 +43,7 @@ void percpu_counter_destroy(struct percp
void percpu_counter_set(struct percpu_counter *fbc, s64 amount);
s64 __percpu_counter_sum(struct percpu_counter *fbc);
int percpu_counter_compare(struct percpu_counter *fbc, s64 rhs);
-void percpu_counter_handle_overflow(struct percpu_counter *fbc);
+void percpu_counter_handle_overflow(struct percpu_counter *fbc, s64 amount);
static __always_inline void percpu_counter_add_batch(struct percpu_counter *fbc,
s64 amount, long batch)
@@ -52,9 +52,10 @@ static __always_inline void percpu_count
preempt_disable();
pcounter = this_cpu_ptr(fbc->counters);
- *pcounter += amount;
- if (unlikely(abs(*pcounter) >= batch))
- percpu_counter_handle_overflow(fbc);
+ if (unlikely(abs(amount + *pcounter) >= batch))
+ percpu_counter_handle_overflow(fbc, amount);
+ else
+ *pcounter += amount;
preempt_enable();
}
diff -puN lib/percpu_counter.c~percpu_counters-inline-the-percpu_counter_add_batch-fastpath-fix lib/percpu_counter.c
--- a/lib/percpu_counter.c~percpu_counters-inline-the-percpu_counter_add_batch-fastpath-fix
+++ a/lib/percpu_counter.c
@@ -72,11 +72,13 @@ EXPORT_SYMBOL(percpu_counter_set);
/*
* Handle overflow of the current cpu's ->count. Premption is disabled.
*/
-void percpu_counter_handle_overflow(struct percpu_counter *fbc)
+void percpu_counter_handle_overflow(struct percpu_counter *fbc, s64 amount)
{
+ long *pcounter = this_cpu_ptr(fbc->counters);
+
spin_lock(&fbc->lock);
- fbc->count += this_cpu_read(*fbc->counters);
- this_cpu_write(*fbc->counters, 0);
+ fbc->count += *pcounter + amount;
+ *pcounter = 0;
spin_unlock(&fbc->lock);
}
EXPORT_SYMBOL(percpu_counter_handle_overflow);
_
Patches currently in -mm which might be from akpm@xxxxxxxxxxxxxxxxxxxx are
typesh-move-misplaced-comment.patch
kfifo-disable-__kfifo_must_check_helper.patch
linux-next.patch
next-remove-localversion.patch
fs-inodec-work-around-bug.patch
arch-x86-kernel-entry_64s-fix-build-with-gas-2161.patch
arch-x86-kernel-entry_32s-i386-too.patch
i-need-old-gcc.patch
arch-alpha-kernel-systblss-remove-debug-check.patch
mm-vmap-area-cache.patch
gcc-46-btrfs-clean-up-unused-variables-bugs.patch
drivers-gpu-drm-radeon-atomc-fix-warning.patch
fs-notify-fanotify-fanotify_userc-fix-warnings.patch
leds-route-kbd-leds-through-the-generic-leds-layer.patch
leds-add-led-trigger-for-input-subsystem-led-events.patch
backlight-add-low-threshold-to-pwm-backlight.patch
serial8250-ratelimit-too-much-work-error.patch
sched-make-sched_param-argument-static-variables-in-some-sched_setscheduler-caller.patch
drivers-message-fusion-mptsasc-fix-warning.patch
drivers-block-aoe-aoeblkc-ratelimit-a-warning-printk.patch
vfs-allow-mnt_want_write-to-sleep.patch
mm.patch
oom-kill-all-threads-sharing-oom-killed-tasks-mm-fix.patch
oom-kill-all-threads-sharing-oom-killed-tasks-mm-fix-fix.patch
oom-rewrite-error-handling-for-oom_adj-and-oom_score_adj-tunables.patch
oom-fix-locking-for-oom_adj-and-oom_score_adj.patch
mm-only-build-per-node-scan_unevictable-functions-when-numa-is-enabled-cleanup.patch
memory-hotplug-unify-is_removable-and-offline-detection-code-checkpatch-fixes.patch
mm-stack-based-kmap_atomic-checkpatch-fixes.patch
mm-stack-based-kmap_atomic-fix.patch
mm-retry-page-fault-when-blocking-on-disk-transfer.patch
mm-retry-page-fault-when-blocking-on-disk-transfer-update-fix.patch
rmap-make-anon_vma_free-static-fix.patch
vmstat-include-compactionh-when-config_compaction-fix.patch
fs-fs-writebackc-restore-lost-comment.patch
mm-memory_hotplugc-make-scan_lru_pages-static.patch
proc-swaps-support-polling-fix.patch
frv-duplicate-output_buffer-of-e03-checkpatch-fixes.patch
hpet-factor-timer-allocate-from-open.patch
hpet-factor-timer-allocate-from-open-fix.patch
drivers-char-hpetc-fix-information-leak-to-userland-fix.patch
kernelh-add-minmax3-macros-fix.patch
include-linux-kernelh-add-__must_check-to-strict_strto.patch
printk-declare-printk_ratelimit_state-in-ratelimith-fix.patch
vsprintfc-use-default-pointer-field-size-for-null-strings-fix.patch
scripts-get_maintainerpl-add-git-blame-rolestats-authored-lines-information.patch
idr-fix-idr_pre_get-locking-description-fix.patch
percpu_counter-rename-__percpu_counter_add-to-percpu_counter_add_batch.patch
percpu_counters-inline-the-percpu_counter_add_batch-fastpath.patch
percpu_counters-inline-the-percpu_counter_add_batch-fastpath-fix.patch
checkpatch-returning-errno-typically-should-be-negative.patch
select-rename-estimate_accuracy-to-select_estimate_accuracy.patch
vcs-add-poll-fasync-support-fix-fix.patch
rtc-rtc-s3c-fix-access-unit-from-byte-to-word-on-rtccon-checkpatch-fixes.patch
drivers-rtc-rtc-jz4740c-add-alarm-function-checkpatch-fixes.patch
gpio-add-support-for-74x164-serial-in-parallel-out-8-bit-shift-register-fix.patch
cgroup_freezer-update_freezer_state-does-incorrect-state-transitions-checkpatch-fixes.patch
memcg-cpu-hotplug-aware-quick-acount_move-detection-checkpatch-fixes.patch
core_pattern-fix-long-parameters-was-truncated-by-core_pattern-handler-update.patch
core_pattern-fix-long-parameters-was-truncated-by-core_pattern-handler-update-2.patch
core_pattern-fix-long-parameters-was-truncated-by-core_pattern-handler-update-2-checkpatch-fixes.patch
proc-stat-fix-scalability-of-irq-sum-of-all-cpu-fix.patch
drivers-char-hvc_consolec-remove-unneeded-__set_current_statetask_running.patch
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fuse-use-release_pages.patch
pps-add-async-pps-event-handler-fix.patch
memstick-add-driver-for-ricoh-r5c592-card-reader-fix.patch
kernel-resourcec-handle-reinsertion-of-an-already-inserted-resource.patch
ramoops-use-the-platform-data-structure-instead-of-module-params-fix.patch
journal_add_journal_head-debug.patch
slab-leaks3-default-y.patch
put_bh-debug.patch
getblk-handle-2tb-devices.patch
memblock-add-input-size-checking-to-memblock_find_region.patch
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