[PATCH v2 4/5] pstore/ram: allow to dump kmesg during regular reboot
From: Pavel Tatashin <pasha.tatashin@soleen.com>
Date: 2020-05-05 15:45:27
Also in:
lkml
Subsystem:
filesystems (vfs and infrastructure), pstore filesystem, the rest · Maintainers:
Alexander Viro, Christian Brauner, Kees Cook, Linus Torvalds
Currently, ramoops is capable to collect dmesg buffer only during panic and oops events. However, it is desirable to optionally allow collecting dmesg buffers during other events as well: reboot, kexec, emergency reboot etc. While, a similar functionality is provided by pstore console it is not the same. Often, console message level is reduced in production due to baud rate limitation of serial consoles. Having a noisy console reduces the boot performance. Thus, if the shutdown dmesg buffer is needed to study the shutdown performance, it is currently not possible to do so with console as by increasing the console output the shutdown time substantially increases as well. Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com> --- fs/pstore/ram.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 223581aeea96..568d9911beae 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c@@ -60,7 +60,12 @@ MODULE_PARM_DESC(mem_type, static int dump_oops = 1; module_param(dump_oops, int, 0600); MODULE_PARM_DESC(dump_oops, - "set to 1 to dump oopses, 0 to only dump panics (default 1)"); + "set to 1 to dump oopses, 0 to only dump panics (default 1), deprecated use max_reason instead"); + +static int max_reason; +module_param(max_reason, int, 0400); +MODULE_PARM_DESC(max_reason, + "maximum reason for kmsg dump. (default 2) "); static int ramoops_ecc; module_param_named(ecc, ramoops_ecc, int, 0600);
@@ -689,6 +694,7 @@ static int ramoops_parse_dt(struct platform_device *pdev, parse_size("pmsg-size", pdata->pmsg_size); parse_size("ecc-size", pdata->ecc_info.ecc_size); parse_size("flags", pdata->flags); + parse_size("max_reason", pdata->max_reason); #undef parse_size
@@ -939,6 +945,7 @@ static void __init ramoops_register_dummy(void) pdata.console_size = ramoops_console_size; pdata.ftrace_size = ramoops_ftrace_size; pdata.pmsg_size = ramoops_pmsg_size; + pdata.max_reason = max_reason; pdata.flags = RAMOOPS_FLAG_FTRACE_PER_CPU; /*
--
2.25.1