| Message ID | 084c136c6bb2d20ca0e91af7ded48306d52bb910.1645210326.git.sweettea-kernel@dorminy.me (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] btrfs: add fs state details to error messages. | expand |
On Fri, Feb 18, 2022 at 02:04:29PM -0500, Sweet Tea Dorminy wrote: > When a filesystem goes read-only due to an error, multiple errors tend > to be reported, some of which are knock-on failures. Logging some > fs_states, if any, in btrfs_handle_fs_error() and btrfs_printk() > helps distinguish the first error from subsequent messages which may > only exist due to an error state. > > Under the new format, most initial errors will look like: > `BTRFS: error (device loop0) in ...` > while subsequent errors will begin with: > `error (device loop0: state E) in ...` > > An initial transaction abort error will look like > `error (device loop0: state X) in ...` > and subsequent messages will contain > `(device loop0: state EX) in ...` I think there should be also BTRFS_FS_STATE_LOG_CLEANUP_ERROR, and the letter maybe more hinting of the error: E - generic error A - transaction abort L - log related errors > > Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> > --- > v2: > - Changed btrfs_state_to_string() for clarity > - Removed superfluous whitespace change > > v1: > - https://lore.kernel.org/linux-btrfs/20220212191042.94954-1-sweettea-kernel@dorminy.me/ > > fs/btrfs/super.c | 53 ++++++++++++++++++++++++++++++++++++++++-------- > 1 file changed, 45 insertions(+), 8 deletions(-) > > diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c > index 4d947ba32da9..42429d68950d 100644 > --- a/fs/btrfs/super.c > +++ b/fs/btrfs/super.c > @@ -66,6 +66,37 @@ static struct file_system_type btrfs_root_fs_type; > > static int btrfs_remount(struct super_block *sb, int *flags, char *data); > > +#define STATE_STRING_PREFACE ": state " > +#define MAX_STATE_CHARS 2 > + > +static void btrfs_state_to_string(const struct btrfs_fs_info *info, char *buf) > +{ > + unsigned int states_printed = 0; > + char *curr = buf; > + > + memcpy(curr, STATE_STRING_PREFACE, sizeof(STATE_STRING_PREFACE)); > + curr += sizeof(STATE_STRING_PREFACE) - 1; > + > + /* If more states are reported, update MAX_STATE_CHARS also */ > + if (test_bit(BTRFS_FS_STATE_ERROR, &info->fs_state)) { > + *curr++ = 'E'; > + states_printed++; > + } > + > + if (test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &info->fs_state)) { > + *curr++ = 'X'; > + states_printed++; > + } > + So if we have more than 2 it may make sense to create a table and not to opencode it like that and then use the constants (MAX_STATE_CHARS) everywhere. For first implementation it's probably ok to have it like three ifs. > + /* If no states were printed, reset the buffer */ > + if (!states_printed) > + curr = buf; > + > + WARN_ON_ONCE(states_printed > MAX_STATE_CHARS); > + > + *curr++ = '\0'; > +} > + > /* > * Generally the error codes correspond to their respective errors, but there > * are a few special cases. > @@ -128,6 +159,7 @@ void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function > { > struct super_block *sb = fs_info->sb; > #ifdef CONFIG_PRINTK > + char statestr[sizeof(STATE_STRING_PREFACE) + MAX_STATE_CHARS]; A size defintion like that could be also predefined. > const char *errstr; > #endif > > @@ -140,6 +172,7 @@ void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function > > #ifdef CONFIG_PRINTK > errstr = btrfs_decode_error(errno); > + btrfs_state_to_string(fs_info, statestr); > if (fmt) { > struct va_format vaf; > va_list args; > @@ -148,12 +181,12 @@ void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function > vaf.fmt = fmt; > vaf.va = &args; > > - pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s (%pV)\n", > - sb->s_id, function, line, errno, errstr, &vaf); > + pr_crit("BTRFS: error (device %s%s) in %s:%d: errno=%d %s (%pV)\n", > + sb->s_id, statestr, function, line, errno, errstr, &vaf); > va_end(args); > } else { > - pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s\n", > - sb->s_id, function, line, errno, errstr); > + pr_crit("BTRFS: error (device %s%s) in %s:%d: errno=%d %s\n", > + sb->s_id, statestr, function, line, errno, errstr); > } > #endif > > @@ -240,11 +273,15 @@ void __cold btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, . > vaf.va = &args; > > if (__ratelimit(ratelimit)) { > - if (fs_info) > - printk("%sBTRFS %s (device %s): %pV\n", lvl, type, > - fs_info->sb->s_id, &vaf); > - else > + if (fs_info) { > + char statestr[sizeof(STATE_STRING_PREFACE) + MAX_STATE_CHARS]; > + > + btrfs_state_to_string(fs_info, statestr); > + printk("%sBTRFS %s (device %s%s): %pV\n", lvl, type, > + fs_info->sb->s_id, statestr, &vaf); > + } else { > printk("%sBTRFS %s: %pV\n", lvl, type, &vaf); > + } > } > > va_end(args); > -- > 2.35.1
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 4d947ba32da9..42429d68950d 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -66,6 +66,37 @@ static struct file_system_type btrfs_root_fs_type; static int btrfs_remount(struct super_block *sb, int *flags, char *data); +#define STATE_STRING_PREFACE ": state " +#define MAX_STATE_CHARS 2 + +static void btrfs_state_to_string(const struct btrfs_fs_info *info, char *buf) +{ + unsigned int states_printed = 0; + char *curr = buf; + + memcpy(curr, STATE_STRING_PREFACE, sizeof(STATE_STRING_PREFACE)); + curr += sizeof(STATE_STRING_PREFACE) - 1; + + /* If more states are reported, update MAX_STATE_CHARS also */ + if (test_bit(BTRFS_FS_STATE_ERROR, &info->fs_state)) { + *curr++ = 'E'; + states_printed++; + } + + if (test_bit(BTRFS_FS_STATE_TRANS_ABORTED, &info->fs_state)) { + *curr++ = 'X'; + states_printed++; + } + + /* If no states were printed, reset the buffer */ + if (!states_printed) + curr = buf; + + WARN_ON_ONCE(states_printed > MAX_STATE_CHARS); + + *curr++ = '\0'; +} + /* * Generally the error codes correspond to their respective errors, but there * are a few special cases. @@ -128,6 +159,7 @@ void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function { struct super_block *sb = fs_info->sb; #ifdef CONFIG_PRINTK + char statestr[sizeof(STATE_STRING_PREFACE) + MAX_STATE_CHARS]; const char *errstr; #endif @@ -140,6 +172,7 @@ void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function #ifdef CONFIG_PRINTK errstr = btrfs_decode_error(errno); + btrfs_state_to_string(fs_info, statestr); if (fmt) { struct va_format vaf; va_list args; @@ -148,12 +181,12 @@ void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function vaf.fmt = fmt; vaf.va = &args; - pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s (%pV)\n", - sb->s_id, function, line, errno, errstr, &vaf); + pr_crit("BTRFS: error (device %s%s) in %s:%d: errno=%d %s (%pV)\n", + sb->s_id, statestr, function, line, errno, errstr, &vaf); va_end(args); } else { - pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s\n", - sb->s_id, function, line, errno, errstr); + pr_crit("BTRFS: error (device %s%s) in %s:%d: errno=%d %s\n", + sb->s_id, statestr, function, line, errno, errstr); } #endif @@ -240,11 +273,15 @@ void __cold btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, . vaf.va = &args; if (__ratelimit(ratelimit)) { - if (fs_info) - printk("%sBTRFS %s (device %s): %pV\n", lvl, type, - fs_info->sb->s_id, &vaf); - else + if (fs_info) { + char statestr[sizeof(STATE_STRING_PREFACE) + MAX_STATE_CHARS]; + + btrfs_state_to_string(fs_info, statestr); + printk("%sBTRFS %s (device %s%s): %pV\n", lvl, type, + fs_info->sb->s_id, statestr, &vaf); + } else { printk("%sBTRFS %s: %pV\n", lvl, type, &vaf); + } } va_end(args);
When a filesystem goes read-only due to an error, multiple errors tend to be reported, some of which are knock-on failures. Logging some fs_states, if any, in btrfs_handle_fs_error() and btrfs_printk() helps distinguish the first error from subsequent messages which may only exist due to an error state. Under the new format, most initial errors will look like: `BTRFS: error (device loop0) in ...` while subsequent errors will begin with: `error (device loop0: state E) in ...` An initial transaction abort error will look like `error (device loop0: state X) in ...` and subsequent messages will contain `(device loop0: state EX) in ...` Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> --- v2: - Changed btrfs_state_to_string() for clarity - Removed superfluous whitespace change v1: - https://lore.kernel.org/linux-btrfs/20220212191042.94954-1-sweettea-kernel@dorminy.me/ fs/btrfs/super.c | 53 ++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 45 insertions(+), 8 deletions(-)