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authorLinus Torvalds <torvalds@linux-foundation.org>2024-05-19 14:02:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2024-05-19 14:02:03 -0700
commiteb6a9339efeb6f3d2b5c86fdf2382cdc293eca2c (patch)
tree3b0f8e71aec70c38cd0fda3f557e3f76a5f644a5 /kernel/watchdog_perf.c
parent16dbfae867cdeb32f3d24cea81193793d5decc61 (diff)
parent5cbcb62dddf5346077feb82b7b0c9254222d3445 (diff)
downloadlwn-eb6a9339efeb6f3d2b5c86fdf2382cdc293eca2c.tar.gz
lwn-eb6a9339efeb6f3d2b5c86fdf2382cdc293eca2c.zip
Merge tag 'mm-nonmm-stable-2024-05-19-11-56' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-mm updates from Andrew Morton: "Mainly singleton patches, documented in their respective changelogs. Notable series include: - Some maintenance and performance work for ocfs2 in Heming Zhao's series "improve write IO performance when fragmentation is high". - Some ocfs2 bugfixes from Su Yue in the series "ocfs2 bugs fixes exposed by fstests". - kfifo header rework from Andy Shevchenko in the series "kfifo: Clean up kfifo.h". - GDB script fixes from Florian Rommel in the series "scripts/gdb: Fixes for $lx_current and $lx_per_cpu". - After much discussion, a coding-style update from Barry Song explaining one reason why inline functions are preferred over macros. The series is "codingstyle: avoid unused parameters for a function-like macro"" * tag 'mm-nonmm-stable-2024-05-19-11-56' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (62 commits) fs/proc: fix softlockup in __read_vmcore nilfs2: convert BUG_ON() in nilfs_finish_roll_forward() to WARN_ON() scripts: checkpatch: check unused parameters for function-like macro Documentation: coding-style: ask function-like macros to evaluate parameters nilfs2: use __field_struct() for a bitwise field selftests/kcmp: remove unused open mode nilfs2: remove calls to folio_set_error() and folio_clear_error() kernel/watchdog_perf.c: tidy up kerneldoc watchdog: allow nmi watchdog to use raw perf event watchdog: handle comma separated nmi_watchdog command line nilfs2: make superblock data array index computation sparse friendly squashfs: remove calls to set the folio error flag squashfs: convert squashfs_symlink_read_folio to use folio APIs scripts/gdb: fix detection of current CPU in KGDB scripts/gdb: make get_thread_info accept pointers scripts/gdb: fix parameter handling in $lx_per_cpu scripts/gdb: fix failing KGDB detection during probe kfifo: don't use "proxy" headers media: stih-cec: add missing io.h media: rc: add missing io.h ...
Diffstat (limited to 'kernel/watchdog_perf.c')
-rw-r--r--kernel/watchdog_perf.c47
1 files changed, 45 insertions, 2 deletions
diff --git a/kernel/watchdog_perf.c b/kernel/watchdog_perf.c
index 8ea00c4a24b2..d577c4a8321e 100644
--- a/kernel/watchdog_perf.c
+++ b/kernel/watchdog_perf.c
@@ -90,6 +90,14 @@ static struct perf_event_attr wd_hw_attr = {
.disabled = 1,
};
+static struct perf_event_attr fallback_wd_hw_attr = {
+ .type = PERF_TYPE_HARDWARE,
+ .config = PERF_COUNT_HW_CPU_CYCLES,
+ .size = sizeof(struct perf_event_attr),
+ .pinned = 1,
+ .disabled = 1,
+};
+
/* Callback function for perf event subsystem */
static void watchdog_overflow_callback(struct perf_event *event,
struct perf_sample_data *data,
@@ -123,6 +131,13 @@ static int hardlockup_detector_event_create(void)
evt = perf_event_create_kernel_counter(wd_attr, cpu, NULL,
watchdog_overflow_callback, NULL);
if (IS_ERR(evt)) {
+ wd_attr = &fallback_wd_hw_attr;
+ wd_attr->sample_period = hw_nmi_get_sample_period(watchdog_thresh);
+ evt = perf_event_create_kernel_counter(wd_attr, cpu, NULL,
+ watchdog_overflow_callback, NULL);
+ }
+
+ if (IS_ERR(evt)) {
pr_debug("Perf event create on CPU %d failed with %ld\n", cpu,
PTR_ERR(evt));
return PTR_ERR(evt);
@@ -133,7 +148,6 @@ static int hardlockup_detector_event_create(void)
/**
* watchdog_hardlockup_enable - Enable the local event
- *
* @cpu: The CPU to enable hard lockup on.
*/
void watchdog_hardlockup_enable(unsigned int cpu)
@@ -152,7 +166,6 @@ void watchdog_hardlockup_enable(unsigned int cpu)
/**
* watchdog_hardlockup_disable - Disable the local event
- *
* @cpu: The CPU to enable hard lockup on.
*/
void watchdog_hardlockup_disable(unsigned int cpu)
@@ -259,3 +272,33 @@ int __init watchdog_hardlockup_probe(void)
}
return ret;
}
+
+/**
+ * hardlockup_config_perf_event - Overwrite config of wd_hw_attr.
+ * @str: number which identifies the raw perf event to use
+ */
+void __init hardlockup_config_perf_event(const char *str)
+{
+ u64 config;
+ char buf[24];
+ char *comma = strchr(str, ',');
+
+ if (!comma) {
+ if (kstrtoull(str, 16, &config))
+ return;
+ } else {
+ unsigned int len = comma - str;
+
+ if (len >= sizeof(buf))
+ return;
+
+ if (strscpy(buf, str, sizeof(buf)) < 0)
+ return;
+ buf[len] = 0;
+ if (kstrtoull(buf, 16, &config))
+ return;
+ }
+
+ wd_hw_attr.type = PERF_TYPE_RAW;
+ wd_hw_attr.config = config;
+}