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Diffstat (limited to '')
| -rw-r--r-- | debian/patches-rt/0093-printk-kmsg_dump-remove-_nolock-variants.patch | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/debian/patches-rt/0093-printk-kmsg_dump-remove-_nolock-variants.patch b/debian/patches-rt/0093-printk-kmsg_dump-remove-_nolock-variants.patch new file mode 100644 index 000000000..6ad034c1a --- /dev/null +++ b/debian/patches-rt/0093-printk-kmsg_dump-remove-_nolock-variants.patch @@ -0,0 +1,226 @@ +From 171ee108014d67150846f1b8f978921cefc7b1e3 Mon Sep 17 00:00:00 2001 +From: John Ogness <john.ogness@linutronix.de> +Date: Mon, 21 Dec 2020 10:27:58 +0106 +Subject: [PATCH 093/323] printk: kmsg_dump: remove _nolock() variants +Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.10/older/patches-5.10.204-rt100.tar.xz + +kmsg_dump_rewind() and kmsg_dump_get_line() are lockless, so there is +no need for _nolock() variants. Remove these functions and switch all +callers of the _nolock() variants. + +The functions without _nolock() were chosen because they are already +exported to kernel modules. + +Signed-off-by: John Ogness <john.ogness@linutronix.de> +--- + arch/powerpc/xmon/xmon.c | 4 +-- + include/linux/kmsg_dump.h | 18 +---------- + kernel/debug/kdb/kdb_main.c | 8 ++--- + kernel/printk/printk.c | 60 +++++-------------------------------- + 4 files changed, 15 insertions(+), 75 deletions(-) + +diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c +index 9f62cca6c594..2eef587bf51d 100644 +--- a/arch/powerpc/xmon/xmon.c ++++ b/arch/powerpc/xmon/xmon.c +@@ -3015,9 +3015,9 @@ dump_log_buf(void) + catch_memory_errors = 1; + sync(); + +- kmsg_dump_rewind_nolock(&iter); ++ kmsg_dump_rewind(&iter); + xmon_start_pagination(); +- while (kmsg_dump_get_line_nolock(&iter, false, buf, sizeof(buf), &len)) { ++ while (kmsg_dump_get_line(&iter, false, buf, sizeof(buf), &len)) { + buf[len] = '\0'; + printf("%s", buf); + } +diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h +index 2fdb10ab1799..86673930c8ea 100644 +--- a/include/linux/kmsg_dump.h ++++ b/include/linux/kmsg_dump.h +@@ -60,18 +60,13 @@ struct kmsg_dumper { + #ifdef CONFIG_PRINTK + void kmsg_dump(enum kmsg_dump_reason reason); + +-bool kmsg_dump_get_line_nolock(struct kmsg_dumper_iter *iter, bool syslog, +- char *line, size_t size, size_t *len); +- + bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog, + char *line, size_t size, size_t *len); + + bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog, + char *buf, size_t size, size_t *len_out); + +-void kmsg_dump_rewind_nolock(struct kmsg_dumper_iter *iter); +- +-void kmsg_dump_rewind(struct kmsg_dumper_iter *dumper_iter); ++void kmsg_dump_rewind(struct kmsg_dumper_iter *iter); + + int kmsg_dump_register(struct kmsg_dumper *dumper); + +@@ -83,13 +78,6 @@ static inline void kmsg_dump(enum kmsg_dump_reason reason) + { + } + +-static inline bool kmsg_dump_get_line_nolock(struct kmsg_dumper_iter *iter, +- bool syslog, const char *line, +- size_t size, size_t *len) +-{ +- return false; +-} +- + static inline bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog, + const char *line, size_t size, size_t *len) + { +@@ -102,10 +90,6 @@ static inline bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool sysl + return false; + } + +-static inline void kmsg_dump_rewind_nolock(struct kmsg_dumper_iter *iter) +-{ +-} +- + static inline void kmsg_dump_rewind(struct kmsg_dumper_iter *iter) + { + } +diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c +index 048baadd7a41..1f5c577b926e 100644 +--- a/kernel/debug/kdb/kdb_main.c ++++ b/kernel/debug/kdb/kdb_main.c +@@ -2182,8 +2182,8 @@ static int kdb_dmesg(int argc, const char **argv) + kdb_set(2, setargs); + } + +- kmsg_dump_rewind_nolock(&iter); +- while (kmsg_dump_get_line_nolock(&iter, 1, NULL, 0, NULL)) ++ kmsg_dump_rewind(&iter); ++ while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL)) + n++; + + if (lines < 0) { +@@ -2215,8 +2215,8 @@ static int kdb_dmesg(int argc, const char **argv) + if (skip >= n || skip < 0) + return 0; + +- kmsg_dump_rewind_nolock(&iter); +- while (kmsg_dump_get_line_nolock(&iter, 1, buf, sizeof(buf), &len)) { ++ kmsg_dump_rewind(&iter); ++ while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) { + if (skip) { + skip--; + continue; +diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c +index dde1696d7564..031ce3f00141 100644 +--- a/kernel/printk/printk.c ++++ b/kernel/printk/printk.c +@@ -3387,7 +3387,7 @@ void kmsg_dump(enum kmsg_dump_reason reason) + } + + /** +- * kmsg_dump_get_line_nolock - retrieve one kmsg log line (unlocked version) ++ * kmsg_dump_get_line - retrieve one kmsg log line + * @iter: kmsg dumper iterator + * @syslog: include the "<4>" prefixes + * @line: buffer to copy the line to +@@ -3402,18 +3402,18 @@ void kmsg_dump(enum kmsg_dump_reason reason) + * + * A return value of FALSE indicates that there are no more records to + * read. +- * +- * The function is similar to kmsg_dump_get_line(), but grabs no locks. + */ +-bool kmsg_dump_get_line_nolock(struct kmsg_dumper_iter *iter, bool syslog, +- char *line, size_t size, size_t *len) ++bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog, ++ char *line, size_t size, size_t *len) + { + struct printk_info info; + unsigned int line_count; + struct printk_record r; ++ unsigned long flags; + size_t l = 0; + bool ret = false; + ++ printk_safe_enter_irqsave(flags); + prb_rec_init_rd(&r, &info, line, size); + + if (!iter->active) +@@ -3437,40 +3437,11 @@ bool kmsg_dump_get_line_nolock(struct kmsg_dumper_iter *iter, bool syslog, + iter->cur_seq = r.info->seq + 1; + ret = true; + out: ++ printk_safe_exit_irqrestore(flags); + if (len) + *len = l; + return ret; + } +- +-/** +- * kmsg_dump_get_line - retrieve one kmsg log line +- * @iter: kmsg dumper iterator +- * @syslog: include the "<4>" prefixes +- * @line: buffer to copy the line to +- * @size: maximum size of the buffer +- * @len: length of line placed into buffer +- * +- * Start at the beginning of the kmsg buffer, with the oldest kmsg +- * record, and copy one record into the provided buffer. +- * +- * Consecutive calls will return the next available record moving +- * towards the end of the buffer with the youngest messages. +- * +- * A return value of FALSE indicates that there are no more records to +- * read. +- */ +-bool kmsg_dump_get_line(struct kmsg_dumper_iter *iter, bool syslog, +- char *line, size_t size, size_t *len) +-{ +- unsigned long flags; +- bool ret; +- +- printk_safe_enter_irqsave(flags); +- ret = kmsg_dump_get_line_nolock(iter, syslog, line, size, len); +- printk_safe_exit_irqrestore(flags); +- +- return ret; +-} + EXPORT_SYMBOL_GPL(kmsg_dump_get_line); + + /** +@@ -3559,22 +3530,6 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper_iter *iter, bool syslog, + } + EXPORT_SYMBOL_GPL(kmsg_dump_get_buffer); + +-/** +- * kmsg_dump_rewind_nolock - reset the iterator (unlocked version) +- * @iter: kmsg dumper iterator +- * +- * Reset the dumper's iterator so that kmsg_dump_get_line() and +- * kmsg_dump_get_buffer() can be called again and used multiple +- * times within the same dumper.dump() callback. +- * +- * The function is similar to kmsg_dump_rewind(), but grabs no locks. +- */ +-void kmsg_dump_rewind_nolock(struct kmsg_dumper_iter *iter) +-{ +- iter->cur_seq = latched_seq_read_nolock(&clear_seq); +- iter->next_seq = prb_next_seq(prb); +-} +- + /** + * kmsg_dump_rewind - reset the iterator + * @iter: kmsg dumper iterator +@@ -3588,7 +3543,8 @@ void kmsg_dump_rewind(struct kmsg_dumper_iter *iter) + unsigned long flags; + + printk_safe_enter_irqsave(flags); +- kmsg_dump_rewind_nolock(iter); ++ iter->cur_seq = latched_seq_read_nolock(&clear_seq); ++ iter->next_seq = prb_next_seq(prb); + printk_safe_exit_irqrestore(flags); + } + EXPORT_SYMBOL_GPL(kmsg_dump_rewind); +-- +2.43.0 + |