[PATCH v1 05/11] pstore/blk: blkoops: support ftrace recorder

WeiXiong Liao
2020-01-20T01:05:50Z

Support recorder for ftrace. To enable ftrace recorder, just make
ftrace_size be greater than 0 and a multiple of 4096.

Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com>
---
fs/pstore/Kconfig | 12 ++++++++
fs/pstore/blkoops.c | 11 +++++++
fs/pstore/blkzone.c | 75 ++++++++++++++++++++++++++++++++++++++++++++--
include/linux/pstore_blk.h | 4 +++
4 files changed, 99 insertions(+), 3 deletions(-)

diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig
index af83ae59f31a..5649218d2821 100644
--- a/fs/pstore/Kconfig
+++ b/fs/pstore/Kconfig
@@ -210,6 +210,18 @@ config PSTORE_BLKOOPS_CONSOLE_SIZE
NOTE that, both kconfig and module parameters can configure blkoops,
but module parameters have priority over kconfig.

+config PSTORE_BLKOOPS_FTRACE_SIZE
+ int "ftrace size in kbytes for blkoops"
+ depends on PSTORE_BLKOOPS
+ depends on PSTORE_FTRACE
+ default 64
+ help
+ This just sets size of ftrace (ftrace_size) for pstore/blk. The
+ value must be a multiple of 4096.
+
+ NOTE that, both kconfig and module parameters can configure blkoops,
+ but module parameters have priority over kconfig.
+
config PSTORE_BLKOOPS_BLKDEV
string "block device for blkoops"
depends on PSTORE_BLKOOPS
diff --git a/fs/pstore/blkoops.c b/fs/pstore/blkoops.c
index 91754795d612..3f28e61c8ecf 100644
--- a/fs/pstore/blkoops.c
+++ b/fs/pstore/blkoops.c
@@ -39,6 +39,10 @@
module_param(console_size, long, 0400);
MODULE_PARM_DESC(console_size, "console size in kbytes");

+static long ftrace_size = -1;
+module_param(ftrace_size, long, 0400);
+MODULE_PARM_DESC(ftrace_size, "ftrace size in kbytes");
+
static int dump_oops = -1;
module_param(dump_oops, int, 0400);
MODULE_PARM_DESC(total_size, "whether dump oops");
@@ -95,6 +99,12 @@
#define DEFAULT_CONSOLE_SIZE 0
#endif

+#ifdef CONFIG_PSTORE_BLKOOPS_FTRACE_SIZE
+#define DEFAULT_FTRACE_SIZE CONFIG_PSTORE_BLKOOPS_FTRACE_SIZE
+#else
+#define DEFAULT_FTRACE_SIZE 0
+#endif
+
#ifdef CONFIG_PSTORE_BLKOOPS_DUMP_OOPS
#define DEFAULT_DUMP_OOPS CONFIG_PSTORE_BLKOOPS_DUMP_OOPS
#else
@@ -150,6 +160,7 @@ int blkoops_register_device(struct blkoops_device *bo_dev)
verify_size(dmesg_size, DEFAULT_DMESG_SIZE, 4096);
verify_size(pmsg_size, DEFAULT_PMSG_SIZE, 4096);
verify_size(console_size, DEFAULT_CONSOLE_SIZE, 4096);
+ verify_size(ftrace_size, DEFAULT_FTRACE_SIZE, 4096);
#undef verify_size
dump_oops = !!(dump_oops < 0 ? DEFAULT_DUMP_OOPS : dump_oops);

diff --git a/fs/pstore/blkzone.c b/fs/pstore/blkzone.c
index 1bb914a2622a..66ae8e2a924b 100644
--- a/fs/pstore/blkzone.c
+++ b/fs/pstore/blkzone.c
@@ -105,10 +105,13 @@ struct blkz_context {
struct blkz_zone **dbzs; /* dmesg block zones */
struct blkz_zone *pbz; /* Pmsg block zone */
struct blkz_zone *cbz; /* console block zone */
+ struct blkz_zone **fbzs; /* Ftrace zones */
unsigned int dmesg_max_cnt;
unsigned int dmesg_read_cnt;
unsigned int pmsg_read_cnt;
unsigned int console_read_cnt;
+ unsigned int ftrace_max_cnt;
+ unsigned int ftrace_read_cnt;
unsigned int dmesg_write_cnt;
/*
* the counter should be recovered when recover.
@@ -297,6 +300,7 @@ static void blkz_flush_all_dirty_zones(struct work_struct *work)
blkz_flush_dirty_zone(cxt->pbz);
blkz_flush_dirty_zone(cxt->cbz);
blkz_flush_dirty_zones(cxt->dbzs, cxt->dmesg_max_cnt);
+ blkz_flush_dirty_zones(cxt->fbzs, cxt->ftrace_max_cnt);
}

static int blkz_recover_dmesg_data(struct blkz_context *cxt)
@@ -513,6 +517,31 @@ static int blkz_recover_zone(struct blkz_context *cxt, struct blkz_zone *zone)
return ret;
}

+static int blkz_recover_zones(struct blkz_context *cxt,
+ struct blkz_zone **zones, unsigned int cnt)
+{
+ int ret;
+ unsigned int i;
+ struct blkz_zone *zone;
+
+ if (!zones)
+ return 0;
+
+ for (i = 0; i < cnt; i++) {
+ zone = zones[i];
+ if (unlikely(!zone))
+ continue;
+ ret = blkz_recover_zone(cxt, zone);
+ if (ret)
+ goto recover_fail;
+ }
+
+ return 0;
+recover_fail:
+ pr_debug("recover %s[%u] failed\n", zone->name, i);
+ return ret;
+}
+
static inline int blkz_recovery(struct blkz_context *cxt)
{
int ret = -EBUSY;
@@ -532,6 +561,10 @@ static inline int blkz_recovery(struct blkz_context *cxt)
if (ret)
goto recover_fail;

+ ret = blkz_recover_zones(cxt, cxt->fbzs, cxt->ftrace_max_cnt);
+ if (ret)
+ goto recover_fail;
+
pr_debug("recover end!\n");
atomic_set(&cxt->recovered, 1);
return 0;
@@ -548,6 +581,7 @@ static int blkz_pstore_open(struct pstore_info *psi)
cxt->dmesg_read_cnt = 0;
cxt->pmsg_read_cnt = 0;
cxt->console_read_cnt = 0;
+ cxt->ftrace_read_cnt = 0;
return 0;
}

@@ -605,6 +639,8 @@ static int blkz_pstore_erase(struct pstore_record *record)
return blkz_record_erase(cxt, cxt->pbz);
case PSTORE_TYPE_CONSOLE:
return blkz_record_erase(cxt, cxt->cbz);
+ case PSTORE_TYPE_FTRACE:
+ return blkz_record_erase(cxt, cxt->fbzs[record->id]);
default: return -EINVAL;
}
}
@@ -759,6 +795,13 @@ static int notrace blkz_pstore_write(struct pstore_record *record)
return blkz_record_write(cxt, cxt->cbz, record);
case PSTORE_TYPE_PMSG:
return blkz_record_write(cxt, cxt->pbz, record);
+ case PSTORE_TYPE_FTRACE: {
+ int zonenum = smp_processor_id();
+
+ if (!cxt->fbzs)
+ return -ENOSPC;
+ return blkz_record_write(cxt, cxt->fbzs[zonenum], record);
+ }
default:
return -EINVAL;
}
@@ -775,6 +818,12 @@ static struct blkz_zone *blkz_read_next_zone(struct blkz_context *cxt)
return zone;
}

+ while (cxt->ftrace_read_cnt < cxt->ftrace_max_cnt) {
+ zone = cxt->fbzs[cxt->ftrace_read_cnt++];
+ if (blkz_old_ok(zone))
+ return zone;
+ }
+
if (cxt->pmsg_read_cnt == 0) {
cxt->pmsg_read_cnt++;
zone = cxt->pbz;
@@ -897,6 +946,9 @@ static ssize_t blkz_pstore_read(struct pstore_record *record)
readop = blkz_dmesg_read;
record->id = cxt->dmesg_read_cnt - 1;
break;
+ case PSTORE_TYPE_FTRACE:
+ record->id = cxt->ftrace_read_cnt - 1;
+ /* fallthrough */
case PSTORE_TYPE_CONSOLE:
/* fallthrough */
case PSTORE_TYPE_PMSG:
@@ -1062,15 +1114,27 @@ static int blkz_cut_zones(struct blkz_context *cxt)
goto free_pmsg;
}

+ off_size += info->ftrace_size;
+ cxt->fbzs = blkz_init_zones(PSTORE_TYPE_FTRACE, &off,
+ info->ftrace_size,
+ info->ftrace_size / nr_cpu_ids,
+ &cxt->ftrace_max_cnt);
+ if (IS_ERR(cxt->fbzs)) {
+ err = PTR_ERR(cxt->fbzs);
+ goto free_console;
+ }
+
cxt->dbzs = blkz_init_zones(PSTORE_TYPE_DMESG, &off,
info->total_size - off_size,
info->dmesg_size, &cxt->dmesg_max_cnt);
if (IS_ERR(cxt->dbzs)) {
err = PTR_ERR(cxt->dbzs);
- goto free_console;
+ goto free_ftrace;
}

return 0;
+free_ftrace:
+ blkz_free_zones(&cxt->fbzs, &cxt->ftrace_max_cnt);
free_console:
blkz_free_zone(&cxt->cbz);
free_pmsg:
@@ -1119,6 +1183,7 @@ int blkz_register(struct blkz_info *info)
check_size(dmesg_size, SECTOR_SIZE);
check_size(pmsg_size, SECTOR_SIZE);
check_size(console_size, SECTOR_SIZE);
+ check_size(ftrace_size, SECTOR_SIZE);

#undef check_size

@@ -1152,6 +1217,7 @@ int blkz_register(struct blkz_info *info)
pr_debug("\tdmesg size : %ld Bytes\n", info->dmesg_size);
pr_debug("\tpmsg size : %ld Bytes\n", info->pmsg_size);
pr_debug("\tconsole size : %ld Bytes\n", info->console_size);
+ pr_debug("\tftrace size : %ld Bytes\n", info->ftrace_size);

err = blkz_cut_zones(cxt);
if (err) {
@@ -1175,13 +1241,16 @@ int blkz_register(struct blkz_info *info)
cxt->pstore.flags |= PSTORE_FLAGS_PMSG;
if (info->console_size)
cxt->pstore.flags |= PSTORE_FLAGS_CONSOLE;
+ if (info->ftrace_size)
+ cxt->pstore.flags |= PSTORE_FLAGS_FTRACE;

- pr_info("Registered %s as blkzone backend for %s%s%s%s\n",
+ pr_info("Registered %s as blkzone backend for %s%s%s%s%s\n",
info->name,
cxt->dbzs && cxt->bzinfo->dump_oops ? "Oops " : "",
cxt->dbzs && cxt->bzinfo->panic_write ? "Panic " : "",
cxt->pbz ? "Pmsg " : "",
- cxt->cbz ? "Console" : "");
+ cxt->cbz ? "Console " : "",
+ cxt->fbzs ? "Ftrace" : "");

err = pstore_register(&cxt->pstore);
if (err) {
diff --git a/include/linux/pstore_blk.h b/include/linux/pstore_blk.h
index 546375e04419..77704c1b404a 100644
--- a/include/linux/pstore_blk.h
+++ b/include/linux/pstore_blk.h
@@ -25,6 +25,9 @@
* @console_size:
* The size of zone for console. Zero means disabled, othewise, it must
* be multiple of SECTOR_SIZE(512).
+ * @ftrace_size:
+ * The size of zone for ftrace. Zero means disabled, othewise, it must
+ * be multiple of SECTOR_SIZE(512).
* @dump_oops:
* Dump oops and panic log or only panic.
* @read, @write:
@@ -60,6 +63,7 @@ struct blkz_info {
unsigned long dmesg_size;
unsigned long pmsg_size;
unsigned long console_size;
+ unsigned long ftrace_size;
int dump_oops;
blkz_read_op read;
blkz_write_op write;
--
1.9.1