[PATCH v2] powerpc/xmon: Allow limiting the size of the paca display
From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2015-08-12 11:55:34
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
The paca display is already more than 24 lines, which can be problematic
if you have an old school 80x24 terminal, or more likely you are on a
virtual terminal which does not scroll for whatever reason.
We'd like to expand the paca display even more, so add a way to limit
the number of lines that are displayed.
This adds a third form of 'dp' which is 'dp # #', where the first number
is the cpu, and the second is the number of lines to display.
Example output:
5:mon> dp 3 6
paca for cpu 0x3 @ c00000000fe00c00:
possible = yes
present = yes
online = yes
lock_token = 0x8000 (0xa)
paca_index = 0x3 (0x8)
kernel_toc = 0xc000000001230300 (0x10)
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
v2: Honour the limit even for the initial lines, and change the
implementation to use goto to bail out early rather than checking
continuously.
arch/powerpc/xmon/xmon.c | 40 +++++++++++++++++++++++++++++-----------
1 file changed, 29 insertions(+), 11 deletions(-)
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index e599259d84fc..2950c6aface4 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c@@ -205,6 +205,7 @@ Commands:\n\ #ifdef CONFIG_PPC64 "\ dp[#] dump paca for current cpu, or cpu #\n\ + dp## dump paca for cpu #, only # lines\n\ dpa dump paca for all possible cpus\n" #endif "\
@@ -2070,9 +2071,10 @@ static void xmon_rawdump (unsigned long adrs, long ndump) } #ifdef CONFIG_PPC64 -static void dump_one_paca(int cpu) +static void dump_one_paca(int cpu, int num_lines) { struct paca_struct *p; + int line; if (setjmp(bus_error_jmp) != 0) { printf("*** Error dumping paca for cpu 0x%x!\n", cpu);
@@ -2082,17 +2084,28 @@ static void dump_one_paca(int cpu) catch_memory_errors = 1; sync(); +#define CHECK_LINE() \ + if (num_lines && line++ >= num_lines) \ + goto out; \ + +#define DUMP(paca, name, format) \ + printf(" %-*s = %#-*"format"\t(0x%lx)\n", 16, #name, 18, \ + paca->name, offsetof(struct paca_struct, name)); \ + CHECK_LINE(); + p = &paca[cpu]; + line = 0; + printf("paca for cpu 0x%x @ %p:\n", cpu, p); + CHECK_LINE(); printf(" %-*s = %s\n", 16, "possible", cpu_possible(cpu) ? "yes" : "no"); + CHECK_LINE(); printf(" %-*s = %s\n", 16, "present", cpu_present(cpu) ? "yes" : "no"); + CHECK_LINE(); printf(" %-*s = %s\n", 16, "online", cpu_online(cpu) ? "yes" : "no"); - -#define DUMP(paca, name, format) \ - printf(" %-*s = %#-*"format"\t(0x%lx)\n", 16, #name, 18, paca->name, \ - offsetof(struct paca_struct, name)); + CHECK_LINE(); DUMP(p, lock_token, "x"); DUMP(p, paca_index, "x");
@@ -2119,8 +2132,10 @@ static void dump_one_paca(int cpu) DUMP(p, irq_work_pending, "x"); DUMP(p, nap_state_lost, "x"); +#undef CHECK_LINE #undef DUMP +out: catch_memory_errors = 0; sync(); }
@@ -2135,12 +2150,12 @@ static void dump_all_pacas(void) } for_each_possible_cpu(cpu) - dump_one_paca(cpu); + dump_one_paca(cpu, 0); } static void dump_pacas(void) { - unsigned long num; + unsigned long num, lines; int c; c = inchar();
@@ -2151,10 +2166,13 @@ static void dump_pacas(void) termch = c; /* Put c back, it wasn't 'a' */ - if (scanhex(&num)) - dump_one_paca(num); - else - dump_one_paca(xmon_owner); + num = xmon_owner; + scanhex(&num); + + lines = 0; + scanhex(&lines); + + dump_one_paca(num, lines); } #endif
--
2.1.4