[Crash-utility] Re: [PATCH v4] make the MAX_MALLOC_BUFS customizable

Date: Mon, 8 Dec 2025 14:01:16 +0530 From: Shivang Upadhyay <shivangu(a)linux.ibm.com&gt; Subject: [Crash-utility] [PATCH v4] make the MAX_MALLOC_BUFS customizable To: devel(a)lists.crash-utility.osci.io Cc: shivangu(a)linux.ibm.com, lijiang(a)redhat.com Message-ID: <20251208083116.436292-1-shivangu(a)linux.ibm.com&gt; the default (and minimum) value of MAX_MALLOC_BUFS is 3072, but can be changed with command line with flag `--max-malloc-bufs`. Signed-off-by: Shivang Upadhyay <shivangu(a)linux.ibm.com&gt; --- defs.h | 8 ++++++++ main.c | 4 ++++ tools.c | 9 ++++++--- 3 files changed, 18 insertions(+), 3 deletions(-) diff --git a/defs.h b/defs.h index ab4aee8..f3de0e5 100644 --- a/defs.h +++ b/defs.h @@ -188,6 +188,13 @@ #define HIST_BLKSIZE (4096) static inline int string_exists(char *s) { return (s ? TRUE : FALSE); } + +static inline int max(int a, int b) { + if (a > b) + return a; + return b; +} + #define STREQ(A, B) (string_exists((char *)A) && string_exists((char *)B) && \ (strcmp((char *)(A), (char *)(B)) == 0)) #define STRNEQ(A, B) (string_exists((char *)A) && string_exists((char *)B) && \ @@ -5608,6 +5615,7 @@ void exec_args_input_file(struct command_table_entry *, struct args_input_file * /* * tools.c */ +extern int MAX_MALLOC_BUFS; FILE *set_error(char *); int __error(int, char *, ...); #define error __error /* avoid conflict with gdb error() */ diff --git a/main.c b/main.c index 71bcc15..247779c 100644 --- a/main.c +++ b/main.c @@ -46,6 +46,7 @@ static struct option long_options[] = { {"version", 0, 0, 0}, {"buildinfo", 0, 0, 0}, {"cpus", required_argument, 0, 0}, + {"max-malloc-bufs", required_argument, 0, 0}, {"no_ikconfig", 0, 0, 0}, {"hyper", 0, 0, 0}, {"p2m_mfn", required_argument, 0, 0}, @@ -163,6 +164,9 @@ main(int argc, char **argv) else if (STREQ(long_options[option_index].name, "cpus")) kt->cpus_override = optarg; + else if (STREQ(long_options[option_index].name, "max-malloc-bufs")) + MAX_MALLOC_BUFS = max(MAX_MALLOC_BUFS, atoi(optarg)); + else if (STREQ(long_options[option_index].name, "hyper")) pc->flags |= XEN_HYPER; diff --git a/tools.c b/tools.c index a9ad18d..69250c4 100644 --- a/tools.c +++ b/tools.c @@ -5698,7 +5698,7 @@ ll_power(long long base, long long exp) #define B32K (4) #define SHARED_BUF_SIZES (B32K+1) -#define MAX_MALLOC_BUFS (2000) +int MAX_MALLOC_BUFS = 3072; /* can be changed from command line args */ #define MAX_CACHE_SIZE (KILOBYTES(32)) struct shared_bufs { @@ -5723,7 +5723,7 @@ struct shared_bufs { long buf_8K_ovf; long buf_32K_ovf; int buf_inuse[SHARED_BUF_SIZES]; - char *malloc_bp[MAX_MALLOC_BUFS]; + char **malloc_bp; long smallest; long largest; long embedded; @@ -5744,6 +5744,7 @@ buf_init(void) bp->smallest = 0x7fffffff; bp->total = 0.0; + bp->malloc_bp = (char**) calloc(MAX_MALLOC_BUFS * sizeof(char*), 1); #ifdef VALGRIND VALGRIND_MAKE_MEM_NOACCESS(&bp->buf_1K, sizeof(bp->buf_1K)); @@ -6130,7 +6131,9 @@ getbuf(long reqsize) dump_shared_bufs(); return ((char *)(long) - error(FATAL, "cannot allocate any more memory!\n")); + error(FATAL, "cannot allocate any more memory!\n" + "try increasing --max-malloc-bufs (current value : %d)\n", + MAX_MALLOC_BUFS)); } /* -- 2.52.0